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Sample records for arthropod taxa conditions

  1. Adaptations and Predispositions of Different Middle European Arthropod Taxa (Collembola, Araneae, Chilopoda, Diplopoda) to Flooding and Drought Conditions

    PubMed Central

    Marx, Michael Thomas; Guhmann, Patrick; Decker, Peter

    2012-01-01

    Simple Summary This review summarizes adaptations and predispositions of different arthropod taxa (springtails, web spiders, millipedes and centipedes) to flood and drought conditions. The main focus sis directed to arthropod species, which are living in Middle European floodplain forests and wetlands, because of the fast change of flood and drought conditions in these habitats. Furthermore the effects of the predicted regional climate change like increasing aperiodic summer flooding and decreasing winter and spring floods are also discussed. Abstract Floodplain forests and wetlands are amongst the most diverse and species rich habitats on earth. Arthropods are a key group for the high diversity pattern of these landscapes, due to the fact that the change between flooding and drought causes in different life cycles and in a variety of adaptations in the different taxa. The floodplain forests and wetlands of Central Amazonia are well investigated and over the last 50 years many adaptations of several hexapod, myriapod and arachnid orders were described. In contrast to Amazonia the Middle European floodplains were less investigated concerning the adaptations of arthropods to flood and drought conditions. This review summarizes the adaptations and predispositions of springtails, web spiders, millipedes and centipedes to the changeable flood and drought conditions of Middle European floodplain forests and wetlands. Furthermore the impact of regional climate change predictions like increasing aperiodic summer floods and the decrease of typical winter and spring floods are discussed in this article. PMID:26487164

  2. Adaptations and Predispositions of Different Middle European Arthropod Taxa (Collembola, Araneae, Chilopoda, Diplopoda) to Flooding and Drought Conditions.

    PubMed

    Marx, Michael Thomas; Guhmann, Patrick; Decker, Peter

    2012-01-01

    Floodplain forests and wetlands are amongst the most diverse and species rich habitats on earth. Arthropods are a key group for the high diversity pattern of these landscapes, due to the fact that the change between flooding and drought causes in different life cycles and in a variety of adaptations in the different taxa. The floodplain forests and wetlands of Central Amazonia are well investigated and over the last 50 years many adaptations of several hexapod, myriapod and arachnid orders were described. In contrast to Amazonia the Middle European floodplains were less investigated concerning the adaptations of arthropods to flood and drought conditions. This review summarizes the adaptations and predispositions of springtails, web spiders, millipedes and centipedes to the changeable flood and drought conditions of Middle European floodplain forests and wetlands. Furthermore the impact of regional climate change predictions like increasing aperiodic summer floods and the decrease of typical winter and spring floods are discussed in this article. PMID:26487164

  3. Selection of Nontarget Arthropod Taxa for Field Research on Transgenic Insecticidal Crops: Using Empirical Data and Statistical Power

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the possible adverse effects of transgenic insecticidal crops is the unintended decline in the abundance of nontarget arthropods. Field trials designed to evaluate potential nontarget effects can be more complex than expected because decisions to conduct field trials and the selection of taxa...

  4. Multi-taxa approach shows consistent shifts in arthropod functional traits along grassland land-use intensity gradient.

    PubMed

    Simons, Nadja K; Weisser, Wolfgang W; Gossner, Martin M

    2016-03-01

    Intensification of land use reduces biodiversity but may also shift the trait composition of communities. Understanding how land use affects single traits and community trait composition, helps to understand why some species are more affected by land use than others. Trait-based analyses are common for plants, but rare for arthropods. We collected literature-based traits for nearly 1000 insect and spider species to test how land- use intensity (including mowing, fertilization, and grazing) across 124 grasslands in three regions of Germany affects community-weighted mean traits across taxa and in single taxa. We additionally measured morphometric traits for more than 150 Heteroptera species and tested whether the weighted mean morphometric traits change with increasing land-use intensity. Community average body size decreased and community average dispersal ability increased from low to high land-use intensity. Furthermore, the relative abundance of herbivores and of specialists among herbivores decreased and the relative abundance of species using the herb layer increased with increasing land-use intensity. Community-weighted means of the morphometric traits in Heteroptera also changed from low to high land-use intensity toward longer and thinner shapes as well as longer appendices (legs, wings, and antenna). While changes in traits with increasing mowing and fertilization intensity were consistent with the combined land-use intensity, community average traits did often not change or with opposite direction under increasing grazing intensity. We conclude that high land-use intensity acts as an environmental filter selecting for on average smaller, more mobile, and less specialized species across taxa. Although trait collection across multiple arthropod taxa is laborious and needs clear trait definitions, it is essential for understanding the functional consequences of biodiversity loss due to land-use intensification. PMID:27197401

  5. Water balance in desert arthropods. Despite their small size, arthropods may be highly adapted for life in xeric conditions.

    PubMed

    Edney, E B

    1967-05-26

    As judged by the number of species, or of individuals, arthropods are an extremely successful group of desert inhabitants. There is very great structural and physiological diversity within the group, and since adaptations to desert life open to one are not open to all. we should not expect to find the maximum possible development of adaptive features in any arthropod simply because it lives in a desert. Most adult insects fly; their larvae and all other arthropods do not, and their adaptations will differ accordingly. Desert beetles have very impermeable cuticles and tolerate high body temperatures, while desert cockroaches live below the sand. have more permeable cuticles, and absorb water vapor. There is probably no single respect in which all desert arthropods differ from insects of other environments. Perhaps a profitable way of viewing desert animals is to recognize that each is a whole organism with a specific collection of adaptations that must be consistent within themselves and which are associated with a specific mode of life and a specific evolutionary history. The arthropod organization is capable of producing highly efficient desert species. There is, however, a converse way of looking at the situation, Which is often neglected but which may be of general biological interest: does the evolution of adaptations to desert environments necessarily involve loss of viability in more mesic habitats? If so, then what are these disavantages- what, for example, is the disadvantage of a highly impermeable cuticle? In some cases the answer is clear: sandroaches need sand dunes to live in because they are morphologically and behaviorly specialized for this habitat. More often the answer is not obvious. PMID:6024185

  6. Conditionally rare taxa disproportionately contribute to temporal changes in microbial diversity.

    PubMed

    Shade, Ashley; Jones, Stuart E; Caporaso, J Gregory; Handelsman, Jo; Knight, Rob; Fierer, Noah; Gilbert, Jack A

    2014-01-01

    Microbial communities typically contain many rare taxa that make up the majority of the observed membership, yet the contribution of this microbial "rare biosphere" to community dynamics is unclear. Using 16S rRNA amplicon sequencing of 3,237 samples from 42 time series of microbial communities from nine different ecosystems (air; marine; lake; stream; adult human skin, tongue, and gut; infant gut; and brewery wastewater treatment), we introduce a new method to detect typically rare microbial taxa that occasionally become very abundant (conditionally rare taxa [CRT]) and then quantify their contributions to temporal shifts in community structure. We discovered that CRT made up 1.5 to 28% of the community membership, represented a broad diversity of bacterial and archaeal lineages, and explained large amounts of temporal community dissimilarity (i.e., up to 97% of Bray-Curtis dissimilarity). Most of the CRT were detected at multiple time points, though we also identified "one-hit wonder" CRT that were observed at only one time point. Using a case study from a temperate lake, we gained additional insights into the ecology of CRT by comparing routine community time series to large disturbance events. Our results reveal that many rare taxa contribute a greater amount to microbial community dynamics than is apparent from their low proportional abundances. This observation was true across a wide range of ecosystems, indicating that these rare taxa are essential for understanding community changes over time. Importance: Microbial communities and their processes are the foundations of ecosystems. The ecological roles of rare microorganisms are largely unknown, but it is thought that they contribute to community stability by acting as a reservoir that can rapidly respond to environmental changes. We investigated the occurrence of typically rare taxa that very occasionally become more prominent in their communities ("conditionally rare"). We quantified conditionally rare

  7. Methane production in terrestrial arthropods.

    PubMed Central

    Hackstein, J H; Stumm, C K

    1994-01-01

    We have screened more than 110 representatives of the different taxa of terrestrial arthropods for methane production in order to obtain additional information about the origins of biogenic methane. Methanogenic bacteria occur in the hindguts of nearly all tropical representatives of millipedes (Diplopoda), cockroaches (Blattaria), termites (Isoptera), and scarab beetles (Scarabaeidae), while such methanogens are absent from 66 other arthropod species investigated. Three types of symbiosis were found: in the first type, the arthropod's hindgut is colonized by free methanogenic bacteria; in the second type, methanogens are closely associated with chitinous structures formed by the host's hindgut; the third type is mediated by intestinal anaerobic protists with intracellular methanogens. Such symbiotic associations are likely to be a characteristic property of the particular taxon. Since these taxa represent many families with thousands of species, the world populations of methane-producing arthropods constitute an enormous biomass. We show that arthropod symbionts can contribute substantially to atmospheric methane. Images PMID:8202505

  8. Methane production in terrestrial arthropods

    SciTech Connect

    Hackstein, J.H.P.; Stumm, C.K. )

    1994-06-07

    The authors have screened more than 110 representatives of the different taxa of terrestrial arthropods for methane production in order to obtain additional information about the origins of biogenic methane. Methanogenic bacteria occur in the hindguts of nearly all tropical representatives of millipedes (Diplopoda), cockroaches (Blattaria), termites (Isoptera), and scarab beetles (Scarabaeidae), while such methanogens are absent from 66 other arthropod species investigated. Three types of symbiosis were found: in the first type, the arthropod's hindgut is colonized by free methanogenic bacteria; in the second type, methanogens are closely associated with chitinous structures formed by the host's hindgut; the third type is mediated by intestinal anaerobic protists with intracellular methanogens. Such symbiotic associations are likely to be a characteristic property of the particular taxon. Since these taxa represent many families with thousands of species, the world populations of methane-producing arthropods constitute an enormous biomass. The authors show that arthropod symbionts can contribute substantially to atmospheric methane.

  9. Arthropod Genetics.

    ERIC Educational Resources Information Center

    Zumwalde, Sharon

    2000-01-01

    Introduces an activity on arthropod genetics that involves phenotype and genotype identification of the creature and the construction process. Includes a list of required materials and directions to build a model arthropod. (YDS)

  10. Effects of a Major Tree Invader on Urban Woodland Arthropods

    PubMed Central

    2015-01-01

    Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity. PMID:26359665

  11. Effects of a Major Tree Invader on Urban Woodland Arthropods.

    PubMed

    Buchholz, Sascha; Tietze, Hedwig; Kowarik, Ingo; Schirmel, Jens

    2015-01-01

    Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity. PMID:26359665

  12. [Conditionally neutral phylogenetic markers of major taxa: a new aspect of the evolution of macromolecules].

    PubMed

    Petrov, N B; Aleshin, V V

    2002-08-01

    The current phase of molecular phylogenetics can be named the 18S rRNA gene era, which is now approaching the end. To date, almost all phyla of metazoans and many taxa of protists are represented in databases of 18S rRNA gene sequences. The elements of the phylogenetic tree of Metazoa inferred from 18S rRNA genes are characterized by unequal validity: some of them seem to be well grounded; others are not adequately supported, and probably will be revised later. The validity of phylogenetic reconstruction is influenced by two main factors: (1) erroneous grouping of long branches that occur because of abnormally high evolution rate; (2) deficit of phylogenetically informative characters. A method for overcoming these difficulties is suggested in addition to known tools: using phylogenetic markers that are stable within individual taxa and evolve by punctuated equilibrium. These markers are least influenced by the convergence caused by a high evolution rate of the entire gene. The nature of these markers of ancient taxa, paradoxical from the perspective of neutral evolution, is discussed, as well as their importance for establishing monophyly of both new large-scale taxonomic groups of invertebrates (Bilateria + Rhombozoa + Orthonectida + Myxozoa + Cnidaria + Placozoa and Echinodermata + Hemichordata) and some major taxa of Nematoda. PMID:12244690

  13. Abundance of broad bacterial taxa in the sargasso sea explained by environmental conditions but not water mass.

    PubMed

    Sjöstedt, Johanna; Martiny, Jennifer B H; Munk, Peter; Riemann, Lasse

    2014-05-01

    To explore the potential linkage between distribution of marine bacterioplankton groups, environmental conditions, and water mass, we investigated the factors determining the abundance of bacterial taxa across the hydrographically complex Subtropical Convergence Zone in the Sargasso Sea. Based on information from 16S rRNA gene clone libraries from various locations and two depths, abundances of the predominant taxa (eubacteria, Archaea, Alphaproteobacteria, Gammaproteobacteria, Bacteroidetes, and the Roseobacter, SAR11, and SAR86 clades) were quantified by real-time PCR. In addition, the abundances of Synechococcus, Prochlorococcus, and picoalgae were determined by flow cytometry. Linear multiple-regression models determining the relative effects of eight environmental variables and of water mass explained 35 to 86% of the variation in abundance of the quantified taxa, even though only one to three variables were significantly related to any particular taxon's abundance. Most of the variation in abundance was explained by depth and chlorophyll a. The predominant phototrophs, Prochlorococcus and picoalgae, were negatively correlated with phosphate, whereas eubacteria, heterotrophic bacteria, and SAR86 were negatively correlated with nitrite. Water mass showed limited importance for explaining the abundance of the taxonomical groups (significant only for Roseobacter, explaining 14% of the variation). The results suggest the potential for predicting the abundance of broad bacterioplankton groups throughout the Sargasso Sea using only a few environmental parameters. PMID:24561593

  14. Late Neogene and Early Quaternary Paleoenvironmental and Paleoclimatic Conditions in Southwestern Europe: Isotopic Analyses on Mammalian Taxa

    PubMed Central

    Domingo, Laura; Koch, Paul L.; Hernández Fernández, Manuel; Fox, David L.; Domingo, M. Soledad; Alberdi, María Teresa

    2013-01-01

    Climatic and environmental shifts have had profound impacts on faunal and floral assemblages globally since the end of the Miocene. We explore the regional expression of these fluctuations in southwestern Europe by constructing long-term records (from ∼11.1 to 0.8 Ma, late Miocene–middle Pleistocene) of carbon and oxygen isotope variations in tooth enamel of different large herbivorous mammals from Spain. Isotopic differences among taxa illuminate differences in ecological niches. The δ13C values (relative to VPDB, mean −10.3±1.1‰; range −13.0 to −7.4‰) are consistent with consumption of C3 vegetation; C4 plants did not contribute significantly to the diets of the selected taxa. When averaged by time interval to examine secular trends, δ13C values increase at ∼9.5 Ma (MN9–MN10), probably related to the Middle Vallesian Crisis when there was a replacement of vegetation adapted to more humid conditions by vegetation adapted to drier and more seasonal conditions, and resulting in the disappearance of forested mammalian fauna. The mean δ13C value drops significantly at ∼4.2−3.7 Ma (MN14–MN15) during the Pliocene Warm Period, which brought more humid conditions to Europe, and returns to higher δ13C values from ∼2.6 Ma onwards (MN16), most likely reflecting more arid conditions as a consequence of the onset of the Northern Hemisphere glaciation. The most notable feature in oxygen isotope records (and mean annual temperature reconstructed from these records) is a gradual drop between MN13 and the middle Pleistocene (∼6.3−0.8 Ma) most likely due to cooling associated with Northern Hemisphere glaciation. PMID:23717470

  15. Late neogene and early quaternary paleoenvironmental and paleoclimatic conditions in southwestern Europe: isotopic analyses on mammalian taxa.

    PubMed

    Domingo, Laura; Koch, Paul L; Hernández Fernández, Manuel; Fox, David L; Domingo, M Soledad; Alberdi, María Teresa

    2013-01-01

    Climatic and environmental shifts have had profound impacts on faunal and floral assemblages globally since the end of the Miocene. We explore the regional expression of these fluctuations in southwestern Europe by constructing long-term records (from ~11.1 to 0.8 Ma, late Miocene-middle Pleistocene) of carbon and oxygen isotope variations in tooth enamel of different large herbivorous mammals from Spain. Isotopic differences among taxa illuminate differences in ecological niches. The δ(13)C values (relative to VPDB, mean -10.3 ± 1.1‰; range -13.0 to -7.4‰) are consistent with consumption of C3 vegetation; C4 plants did not contribute significantly to the diets of the selected taxa. When averaged by time interval to examine secular trends, δ(13)C values increase at ~9.5 Ma (MN9-MN10), probably related to the Middle Vallesian Crisis when there was a replacement of vegetation adapted to more humid conditions by vegetation adapted to drier and more seasonal conditions, and resulting in the disappearance of forested mammalian fauna. The mean δ(13)C value drops significantly at ~4.2-3.7 Ma (MN14-MN15) during the Pliocene Warm Period, which brought more humid conditions to Europe, and returns to higher δ(13)C values from ~2.6 Ma onwards (MN16), most likely reflecting more arid conditions as a consequence of the onset of the Northern Hemisphere glaciation. The most notable feature in oxygen isotope records (and mean annual temperature reconstructed from these records) is a gradual drop between MN13 and the middle Pleistocene (~6.3-0.8 Ma) most likely due to cooling associated with Northern Hemisphere glaciation. PMID:23717470

  16. Trees as templates for tropical litter arthropod diversity.

    PubMed

    Donoso, David A; Johnston, Mary K; Kaspari, Michael

    2010-09-01

    Increased tree species diversity in the tropics is associated with even greater herbivore diversity, but few tests of tree effects on litter arthropod diversity exist. We studied whether tree species influence patchiness in diversity and abundance of three common soil arthropod taxa (ants, gamasid mites, and oribatid mites) in a Panama forest. The tree specialization hypothesis proposes that tree-driven habitat heterogeneity maintains litter arthropod diversity. We tested whether tree species differed in resource quality and quantity of their leaf litter and whether more heterogeneous litter supports more arthropod species. Alternatively, the abundance-extinction hypothesis states that arthropod diversity increases with arthropod abundance, which in turn tracks resource quantity (e.g., litter depth). We found little support for the hypothesis that tropical trees are templates for litter arthropod diversity. Ten tree species differed in litter depth, chemistry, and structural variability. However, the extent of specialization of invertebrates on particular tree taxa was low and the more heterogeneous litter between trees failed to support higher arthropod diversity. Furthermore, arthropod diversity did not track abundance or litter depth. The lack of association between tree species and litter arthropods suggests that factors other than tree species diversity may better explain the high arthropod diversity in tropical forests. PMID:20349247

  17. An armoured Cambrian lobopodian from China with arthropod-like appendages.

    PubMed

    Liu, Jianni; Steiner, Michael; Dunlop, Jason A; Keupp, Helmut; Shu, Degan; Ou, Qiang; Han, Jian; Zhang, Zhifei; Zhang, Xingliang

    2011-02-24

    Cambrian fossil Lagerstätten preserving soft-bodied organisms have contributed much towards our understanding of metazoan origins. Lobopodians are a particularly interesting group that diversified and flourished in the Cambrian seas. Resembling 'worms with legs', they have long attracted much attention in that they may have given rise to both Onychophora (velvet worms) and Tardigrada (water bears), as well as to arthropods in general. Here we describe Diania cactiformis gen. et sp. nov. as an 'armoured' lobopodian from the Chengjiang fossil Lagerstätte (Cambrian Stage 3), Yunnan, southwestern China. Although sharing features with other typical lobopodians, it is remarkable for possessing robust and probably sclerotized appendages, with what appear to be articulated elements. In terms of limb morphology it is therefore closer to the arthropod condition, to our knowledge, than any lobopodian recorded until now. Phylogenetic analysis recovers it in a derived position, close to Arthropoda; thus, it seems to belong to a grade of organization close to the point of becoming a true arthropod. Further, D. cactiformis could imply that arthropodization (sclerotization of the limbs) preceded arthrodization (sclerotization of the body). Comparing our fossils with other lobopodian appendage morphologies--see Kerygmachela, Jianshanopodia and Megadictyon--reinforces the hypothesis that the group as a whole is paraphyletic, with different taxa expressing different grades of arthropodization. PMID:21350485

  18. Evolution, discovery, and interpretations of arthropod mushroom bodies.

    PubMed

    Strausfeld, N J; Hansen, L; Li, Y; Gomez, R S; Ito, K

    1998-01-01

    Mushroom bodies are prominent neuropils found in annelids and in all arthropod groups except crustaceans. First explicitly identified in 1850, the mushroom bodies differ in size and complexity between taxa, as well as between different castes of a single species of social insect. These differences led some early biologists to suggest that the mushroom bodies endow an arthropod with intelligence or the ability to execute voluntary actions, as opposed to innate behaviors. Recent physiological studies and mutant analyses have led to divergent interpretations. One interpretation is that the mushroom bodies conditionally relay to higher protocerebral centers information about sensory stimuli and the context in which they occur. Another interpretation is that they play a central role in learning and memory. Anatomical studies suggest that arthropod mushroom bodies are predominately associated with olfactory pathways except in phylogenetically basal insects. The prominent olfactory input to the mushroom body calyces in more recent insect orders is an acquired character. An overview of the history of research on the mushroom bodies, as well as comparative and evolutionary considerations, provides a conceptual framework for discussing the roles of these neuropils. PMID:10454370

  19. Evolution, Discovery, and Interpretations of Arthropod Mushroom Bodies

    PubMed Central

    Strausfeld, Nicholas J.; Hansen, Lars; Li, Yongsheng; Gomez, Robert S.; Ito, Kei

    1998-01-01

    Mushroom bodies are prominent neuropils found in annelids and in all arthropod groups except crustaceans. First explicitly identified in 1850, the mushroom bodies differ in size and complexity between taxa, as well as between different castes of a single species of social insect. These differences led some early biologists to suggest that the mushroom bodies endow an arthropod with intelligence or the ability to execute voluntary actions, as opposed to innate behaviors. Recent physiological studies and mutant analyses have led to divergent interpretations. One interpretation is that the mushroom bodies conditionally relay to higher protocerebral centers information about sensory stimuli and the context in which they occur. Another interpretation is that they play a central role in learning and memory. Anatomical studies suggest that arthropod mushroom bodies are predominately associated with olfactory pathways except in phylogenetically basal insects. The prominent olfactory input to the mushroom body calyces in more recent insect orders is an acquired character. An overview of the history of research on the mushroom bodies, as well as comparative and evolutionary considerations, provides a conceptual framework for discussing the roles of these neuropils. PMID:10454370

  20. Responses of prairie arthropod communities to fire and fertilizer: Balancing plant and arthropod conservation

    USGS Publications Warehouse

    Hartley, M.K.; Rogers, W.E.; Siemann, E.; Grace, J.

    2007-01-01

    Fire is an important tool for limiting woody plant invasions into prairies, but using fire management to maintain grassland plant communities may inadvertently reduce arthropod diversity. To test this, we established twenty-four 100 m2 plots in a tallgrass prairie in Galveston County, Texas, in spring 2000. Plots were assigned a fire (no burn, one time burn [2000], two time burn [2000, 2001]) and fertilization treatment (none, NPK addition) in a full factorial design. Fertilization treatments allowed us to examine the effects of fire at a different level of productivity. We measured plant cover by species and sampled arthropods with sweep nets during the 2001 growing season. Path analysis indicated that fertilization reduced while annual fires increased arthropod diversity via increases and decreases in woody plant abundance, respectively. There was no direct effect of fire on arthropod diversity or abundance. Diptera and Homoptera exhibited particularly strong positive responses to fires. Lepidoptera had a negative response to nutrient enrichment. Overall, the negative effects of fire on the arthropod community were minor in contrast to the strong positive indirect effects of small-scale burning on arthropod diversity if conservation of particular taxa is not a priority. The same fire regime that minimized woody plant invasion also maximized arthropod diversity.

  1. Ecotoxicological study of insecticide effects on arthropods in common bean.

    PubMed

    de Barros, Emerson Cristi; Ventura, Hudson Vaner; Gontijo, Pablo Costa; Pereira, Renata Ramos; Picanço, Marcelo Coutinho

    2015-01-01

    Arthropods are an important group of macroorganisms that work to maintain ecosystem health. Despite the agricultural benefits of chemical control against arthropod pests, insecticides can cause environmental damage. We examined the effects of one and two applications of the insecticides chlorfenapyr (0.18 liters a.i. ha-1) and methamidophos (0.45 liters a.i. ha-1), both independently and in combination, on arthropods in plots of common bean. The experiment was repeated for two growing seasons. Principal response curve, richness estimator, and Shannon-Wiener diversity index analyses were performed. The insecticides generally affected the frequency, richness, diversity, and relative abundance of the arthropods. In addition, the arthropods did not experience recovery after the insecticide applications. The results suggest that the insecticide impacts were sufficiently drastic to eliminate many taxa from the studied common bean plots. PMID:25700537

  2. Ecotoxicological Study of Insecticide Effects on Arthropods in Common Bean

    PubMed Central

    de Barros, Emerson Cristi; Ventura, Hudson Vaner; Gontijo, Pablo Costa; Pereira, Renata Ramos; Picanço, Marcelo Coutinho

    2015-01-01

    Arthropods are an important group of macroorganisms that work to maintain ecosystem health. Despite the agricultural benefits of chemical control against arthropod pests, insecticides can cause environmental damage. We examined the effects of one and two applications of the insecticides chlorfenapyr (0.18 liters a.i. ha-1) and methamidophos (0.45 liters a.i. ha-1), both independently and in combination, on arthropods in plots of common bean. The experiment was repeated for two growing seasons. Principal response curve, richness estimator, and Shannon–Wiener diversity index analyses were performed. The insecticides generally affected the frequency, richness, diversity, and relative abundance of the arthropods. In addition, the arthropods did not experience recovery after the insecticide applications. The results suggest that the insecticide impacts were sufficiently drastic to eliminate many taxa from the studied common bean plots. PMID:25700537

  3. LONG-PCR AS A TOOL FOR DETECTING REARRANGEMENTS OF ARTHROPOD MTDNA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rearrangements of the mitochondrial DNA gene order have been used to help define the pattern of evolutionary divergence in arthropod taxa. We have employed a combination of highly conserved insect-based PCR primers with long-PCR to survey fourteen non-insect arthropods for mitochondrial gene rearra...

  4. Arthropods in Biological Control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article reports the use of insect colloidal artificial diets suitable for the rearing of economically important arthropods, such as Lygus lineolaris, Lygus hesperus, Coleomegilla maculata, and Phytoseiulus persimilis The different diets contain key nutrients such as proteins, carbohydrates, vi...

  5. Grandeur Alliances: Symbiont Metabolic Integration and Obligate Arthropod Hematophagy.

    PubMed

    Rio, Rita V M; Attardo, Geoffrey M; Weiss, Brian L

    2016-09-01

    Several arthropod taxa live exclusively on vertebrate blood. This food source lacks essential metabolites required for the maintenance of metabolic homeostasis, and as such, these arthropods have formed symbioses with nutrient-supplementing microbes that facilitate their host's 'hematophagous' feeding ecology. Herein we highlight metabolic contributions of bacterial symbionts that reside within tsetse flies, bed bugs, lice, reduviid bugs, and ticks, with specific emphasis on B vitamin and cofactor biosynthesis. Importantly, these arthropods can transmit pathogens of medical and veterinary relevance and/or cause infestations that induce psychological and dermatological distress. Microbial metabolites, and the biochemical pathways that generate them, can serve as specific targets of novel control mechanisms aimed at disrupting the metabolism of hematophagous arthropods, thus combatting pest invasion and vector-borne pathogen transmission. PMID:27236581

  6. Acquisition of Cry1Ac Protein by Non-Target Arthropods in Bt Soybean Fields

    PubMed Central

    Yu, Huilin; Romeis, Jörg; Li, Yunhe; Li, Xiangju; Wu, Kongming

    2014-01-01

    Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean. PMID:25110881

  7. Acquisition of Cry1Ac protein by non-target arthropods in Bt soybean fields.

    PubMed

    Yu, Huilin; Romeis, Jörg; Li, Yunhe; Li, Xiangju; Wu, Kongming

    2014-01-01

    Soybean tissue and arthropods were collected in Bt soybean fields in China at different times during the growing season to investigate the exposure of arthropods to the plant-produced Cry1Ac toxin and the transmission of the toxin within the food web. Samples from 52 arthropod species/taxa belonging to 42 families in 10 orders were analysed for their Cry1Ac content using enzyme-linked immunosorbent assay (ELISA). Among the 22 species/taxa for which three samples were analysed, toxin concentration was highest in the grasshopper Atractomorpha sinensis and represented about 50% of the concentration in soybean leaves. Other species/taxa did not contain detectable toxin or contained a concentration that was between 1 and 10% of that detected in leaves. These Cry1Ac-positive arthropods included a number of mesophyll-feeding Hemiptera, a cicadellid, a curculionid beetle and, among the predators, a thomisid spider and an unidentified predatory bug belonging to the Anthocoridae. Within an arthropod species/taxon, the Cry1Ac content sometimes varied between life stages (nymphs/larvae vs. adults) and sampling dates (before, during, and after flowering). Our study is the first to provide information on Cry1Ac-expression levels in soybean plants and Cry1Ac concentrations in non-target arthropods in Chinese soybean fields. The data will be useful for assessing the risk of non-target arthropod exposure to Cry1Ac in soybean. PMID:25110881

  8. Effects of large herbivores on grassland arthropod diversity

    PubMed Central

    van Klink, R; van der Plas, F; van Noordwijk, C G E (Toos); WallisDeVries, M F; Olff, H

    2015-01-01

    Both arthropods and large grazing herbivores are important components and drivers of biodiversity in grassland ecosystems, but a synthesis of how arthropod diversity is affected by large herbivores has been largely missing. To fill this gap, we conducted a literature search, which yielded 141 studies on this topic of which 24 simultaneously investigated plant and arthropod diversity. Using the data from these 24 studies, we compared the responses of plant and arthropod diversity to an increase in grazing intensity. This quantitative assessment showed no overall significant effect of increasing grazing intensity on plant diversity, while arthropod diversity was generally negatively affected. To understand these negative effects, we explored the mechanisms by which large herbivores affect arthropod communities: direct effects, changes in vegetation structure, changes in plant community composition, changes in soil conditions, and cascading effects within the arthropod interaction web. We identify three main factors determining the effects of large herbivores on arthropod diversity: (i) unintentional predation and increased disturbance, (ii) decreases in total resource abundance for arthropods (biomass) and (iii) changes in plant diversity, vegetation structure and abiotic conditions. In general, heterogeneity in vegetation structure and abiotic conditions increases at intermediate grazing intensity, but declines at both low and high grazing intensity. We conclude that large herbivores can only increase arthropod diversity if they cause an increase in (a)biotic heterogeneity, and then only if this increase is large enough to compensate for the loss of total resource abundance and the increased mortality rate. This is expected to occur only at low herbivore densities or with spatio-temporal variation in herbivore densities. As we demonstrate that arthropod diversity is often more negatively affected by grazing than plant diversity, we strongly recommend considering the

  9. Effects of large herbivores on grassland arthropod diversity.

    PubMed

    van Klink, R; van der Plas, F; van Noordwijk, C G E Toos; WallisDeVries, M F; Olff, H

    2015-05-01

    Both arthropods and large grazing herbivores are important components and drivers of biodiversity in grassland ecosystems, but a synthesis of how arthropod diversity is affected by large herbivores has been largely missing. To fill this gap, we conducted a literature search, which yielded 141 studies on this topic of which 24 simultaneously investigated plant and arthropod diversity. Using the data from these 24 studies, we compared the responses of plant and arthropod diversity to an increase in grazing intensity. This quantitative assessment showed no overall significant effect of increasing grazing intensity on plant diversity, while arthropod diversity was generally negatively affected. To understand these negative effects, we explored the mechanisms by which large herbivores affect arthropod communities: direct effects, changes in vegetation structure, changes in plant community composition, changes in soil conditions, and cascading effects within the arthropod interaction web. We identify three main factors determining the effects of large herbivores on arthropod diversity: (i) unintentional predation and increased disturbance, (ii) decreases in total resource abundance for arthropods (biomass) and (iii) changes in plant diversity, vegetation structure and abiotic conditions. In general, heterogeneity in vegetation structure and abiotic conditions increases at intermediate grazing intensity, but declines at both low and high grazing intensity. We conclude that large herbivores can only increase arthropod diversity if they cause an increase in (a)biotic heterogeneity, and then only if this increase is large enough to compensate for the loss of total resource abundance and the increased mortality rate. This is expected to occur only at low herbivore densities or with spatio-temporal variation in herbivore densities. As we demonstrate that arthropod diversity is often more negatively affected by grazing than plant diversity, we strongly recommend considering the

  10. Ectomycota Associated with Arthropods from Bat Hibernacula in Eastern Canada, with Particular Reference to Pseudogymnoasucs destructans.

    PubMed

    Vanderwolf, Karen J; Malloch, David; McAlpine, Donald F

    2016-01-01

    The introduction of Pseudogymnoascus destructans (Pd) to North America, agent of white-nose syndrome in hibernating bats, has increased interest in fungi from underground habitats. While bats are assumed to be the main vector transmitting Pd cave-to-cave, the role of other fauna is unexplored. We documented the fungi associated with over-wintering arthropods in Pd-positive hibernacula, including sites where bats had been recently extirpated or near-extirpated, to determine if arthropods carried Pd, and to compare fungal assemblages on arthropods to bats. We isolated 87 fungal taxa in 64 genera from arthropods. Viable Pd was cultured from 15.3% of arthropods, most frequently from harvestmen (Nelima elegans). Fungal assemblages on arthropods were similar to those on bats. The different fungal assemblages documented among arthropods may be due to divergent patterns of movement, aggregation, feeding, or other factors. While it is unlikely that arthropods play a major role in the transmission dynamics of Pd, we demonstrate that arthropods may carry viable Pd spores and therefore have the potential to transport Pd, either naturally or anthropogenically, within or among hibernacula. This underlines the need for those entering hibernacula to observe decontamination procedures and for such procedures to evolve as our understanding of potential mechanisms of Pd dispersal improve. PMID:27110827

  11. Ectomycota Associated with Arthropods from Bat Hibernacula in Eastern Canada, with Particular Reference to Pseudogymnoascus destructans

    PubMed Central

    Vanderwolf, Karen J.; Malloch, David; McAlpine, Donald F.

    2016-01-01

    The introduction of Pseudogymnoascus destructans (Pd) to North America, agent of white-nose syndrome in hibernating bats, has increased interest in fungi from underground habitats. While bats are assumed to be the main vector transmitting Pd cave-to-cave, the role of other fauna is unexplored. We documented the fungi associated with over-wintering arthropods in Pd-positive hibernacula, including sites where bats had been recently extirpated or near-extirpated, to determine if arthropods carried Pd, and to compare fungal assemblages on arthropods to bats. We isolated 87 fungal taxa in 64 genera from arthropods. Viable Pd was cultured from 15.3% of arthropods, most frequently from harvestmen (Nelima elegans). Fungal assemblages on arthropods were similar to those on bats. The different fungal assemblages documented among arthropods may be due to divergent patterns of movement, aggregation, feeding, or other factors. While it is unlikely that arthropods play a major role in the transmission dynamics of Pd, we demonstrate that arthropods may carry viable Pd spores and therefore have the potential to transport Pd, either naturally or anthropogenically, within or among hibernacula. This underlines the need for those entering hibernacula to observe decontamination procedures and for such procedures to evolve as our understanding of potential mechanisms of Pd dispersal improve. PMID:27110827

  12. Temporal dynamics of arthropods on six tree species in dry woodlands on the Caribbean Island of Puerto Rico.

    PubMed

    Beltrán, William; Wunderle, Joseph M

    2014-01-01

    The seasonal dynamics of foliage arthropod populations are poorly studied in tropical dry forests despite the importance of these studies for understanding arthropod population responses to environmental change. We monitored the abundance, temporal distributions, and body size of arthropods in five naturalized alien and one native tree species to characterize arthropod seasonality in dry novel Prosopis-Leucaena woodlands in Puerto Rico. A branch clipping method was used monthly to sample foliage arthropod abundance over 39 mo. Seasonal patterns of rainfall and abundance within various arthropod taxa were highly variable from year to year. Abundance for most taxa did not show significant seasonality over the 3 yr, although most taxa had abundance peaks each year. However, Homoptera displayed high seasonality with significant temporal aggregations in each year. Formicidae, Orthoptera, and Coleoptera showed high variation in abundance between wet and dry periods, whereas Hemiptera were consistently more abundant in the wet period. Seasonal differences in mean abundance were found only in a few taxa on Tamarindus indica L., Bucida buceras L., Pithecellobium dulce, and (Roxburgh) Benth. Mean arthropod abundance varied among tree species, with highest numbers on Prosopis juliflora, (Swartz) De Candolle, Pi. dulce, Leucaena leucocephala, and (Lamarck) de Wit. Abundance of Araneae, Orthoptera, Coleoptera, Lepidoptera larvae, and all arthropods showed weak relationships with one or more climatic variables (rainfall, maximum temperature, or relative humidity). Body size of arthropods was usually largest during the dry periods. Overall, total foliage arthropod abundance showed no consistent seasonality among years, which may become a more common trend in dry forests and woodlands in the Caribbean if seasonality of rainfall becomes less predictable. PMID:25502036

  13. Temporal Dynamics of Arthropods on Six Tree Species in Dry Woodlands on the Caribbean Island of Puerto Rico

    PubMed Central

    Beltrán, William; Wunderle, Joseph M.

    2014-01-01

    The seasonal dynamics of foliage arthropod populations are poorly studied in tropical dry forests despite the importance of these studies for understanding arthropod population responses to environmental change. We monitored the abundance, temporal distributions, and body size of arthropods in five naturalized alien and one native tree species to characterize arthropod seasonality in dry novel Prosopis–Leucaena woodlands in Puerto Rico. A branch clipping method was used monthly to sample foliage arthropod abundance over 39 mo. Seasonal patterns of rainfall and abundance within various arthropod taxa were highly variable from year to year. Abundance for most taxa did not show significant seasonality over the 3 yr, although most taxa had abundance peaks each year. However, Homoptera displayed high seasonality with significant temporal aggregations in each year. Formicidae, Orthoptera, and Coleoptera showed high variation in abundance between wet and dry periods, whereas Hemiptera were consistently more abundant in the wet period. Seasonal differences in mean abundance were found only in a few taxa on Tamarindus indica L., Bucida buceras L., Pithecellobium dulce, and (Roxburgh) Benth. Mean arthropod abundance varied among tree species, with highest numbers on Prosopis juliflora, (Swartz) De Candolle, Pi. dulce, Leucaena leucocephala, and (Lamarck) de Wit. Abundance of Araneae, Orthoptera, Coleoptera, Lepidoptera larvae, and all arthropods showed weak relationships with one or more climatic variables (rainfall, maximum temperature, or relative humidity). Body size of arthropods was usually largest during the dry periods. Overall, total foliage arthropod abundance showed no consistent seasonality among years, which may become a more common trend in dry forests and woodlands in the Caribbean if seasonality of rainfall becomes less predictable. PMID:25502036

  14. Arthropods vector grapevine trunk disease pathogens.

    PubMed

    Moyo, P; Allsopp, E; Roets, F; Mostert, L; Halleen, F

    2014-10-01

    Arthropod-mediated dispersal of pathogens is known in many cropping systems but has never been demonstrated for grapevine trunk disease pathogens. Arthropods from vineyards were screened for the presence of pathogens associated with Petri disease and esca using cultural and molecular techniques. The ability of the most abundant pathogen-carrying species to inoculate healthy grapevine vascular tissues was also determined. Millipedes and ants were allowed to associate with a DsRed- Express-transformed Phaeomoniella chlamydospora, after which they were exposed to freshly pruned healthy grapevines under controlled conditions and wounds were monitored for subsequent infection. In addition, the possibility of millipede excreta, commonly found on pruning wounds in the field, to act as inoculum source was determined. A diverse arthropod fauna was associated with declining grapevines and many of these carried trunk disease pathogens. However, spiders, the ant Crematogaster peringueyi, and the millipede Ommattoiulus moreleti were the most abundant pathogen carriers. The ant and millipede species fed on pruning wound sap and effectively transmitted trunk disease pathogens. Millipede excreta contained viable spores of Phaeomoniella chlamydospora and may serve as an inoculum source. Numerous arthropods, including beneficial predators, are potential vectors of grapevine trunk disease pathogens. Our results highlight the need for an integrated approach, including targeted management of ants and millipedes at the time of pruning, to limit the spread of grapevine trunk diseases. PMID:24624953

  15. Dynamics of the Leaf-Litter Arthropod Fauna Following Fire in a Neotropical Woodland Savanna

    PubMed Central

    Vasconcelos, Heraldo L.; Pacheco, Renata; Silva, Raphael C.; Vasconcelos, Pedro B.; Lopes, Cauê T.; Costa, Alan N.; Bruna, Emilio M.

    2009-01-01

    Fire is an important agent of disturbance in tropical savannas, but relatively few studies have analyzed how soil-and-litter dwelling arthropods respond to fire disturbance despite the critical role these organisms play in nutrient cycling and other biogeochemical processes. Following the incursion of a fire into a woodland savanna ecological reserve in Central Brazil, we monitored the dynamics of litter-arthropod populations for nearly two years in one burned and one unburned area of the reserve. We also performed a reciprocal transplant experiment to determine the effects of fire and litter type on the dynamics of litter colonization by arthropods. Overall arthropod abundance, the abundance of individual taxa, the richness of taxonomic groups, and the species richness of individual taxa (Formiciade) were lower in the burned site. However, both the ordinal-level composition of the litter arthropod fauna and the species-level composition of the litter ant fauna were not dramatically different in the burned and unburned sites. There is evidence that seasonality of rainfall interacts with fire, as differences in arthropod abundance and diversity were more pronounced in the dry than in the wet season. For many taxa the differences in abundance between burned and unburned sites were maintained even when controlling for litter availability and quality. In contrast, differences in abundance for Collembola, Formicidae, and Thysanoptera were only detected in the unmanipulated samples, which had a lower amount of litter in the burned than in the unburned site throughout most of our study period. Together these results suggest that arthropod density declines in fire-disturbed areas as a result of direct mortality, diminished resources (i.e., reduced litter cover) and less favorable microclimate (i.e., increased litter desiccation due to reduction in tree cover). Although these effects were transitory, there is evidence that the increasingly prevalent fire return interval of

  16. Dynamics of the leaf-litter arthropod fauna following fire in a neotropical woodland savanna.

    PubMed

    Vasconcelos, Heraldo L; Pacheco, Renata; Silva, Raphael C; Vasconcelos, Pedro B; Lopes, Cauê T; Costa, Alan N; Bruna, Emilio M

    2009-01-01

    Fire is an important agent of disturbance in tropical savannas, but relatively few studies have analyzed how soil-and-litter dwelling arthropods respond to fire disturbance despite the critical role these organisms play in nutrient cycling and other biogeochemical processes. Following the incursion of a fire into a woodland savanna ecological reserve in Central Brazil, we monitored the dynamics of litter-arthropod populations for nearly two years in one burned and one unburned area of the reserve. We also performed a reciprocal transplant experiment to determine the effects of fire and litter type on the dynamics of litter colonization by arthropods. Overall arthropod abundance, the abundance of individual taxa, the richness of taxonomic groups, and the species richness of individual taxa (Formiciade) were lower in the burned site. However, both the ordinal-level composition of the litter arthropod fauna and the species-level composition of the litter ant fauna were not dramatically different in the burned and unburned sites. There is evidence that seasonality of rainfall interacts with fire, as differences in arthropod abundance and diversity were more pronounced in the dry than in the wet season. For many taxa the differences in abundance between burned and unburned sites were maintained even when controlling for litter availability and quality. In contrast, differences in abundance for Collembola, Formicidae, and Thysanoptera were only detected in the unmanipulated samples, which had a lower amount of litter in the burned than in the unburned site throughout most of our study period. Together these results suggest that arthropod density declines in fire-disturbed areas as a result of direct mortality, diminished resources (i.e., reduced litter cover) and less favorable microclimate (i.e., increased litter desiccation due to reduction in tree cover). Although these effects were transitory, there is evidence that the increasingly prevalent fire return interval of

  17. Hematopoiesis and hematopoietic organs in arthropods.

    PubMed

    Grigorian, Melina; Hartenstein, Volker

    2013-03-01

    Hemocytes (blood cells) are motile cells that move throughout the extracellular space and that exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and the body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self-renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review, we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species. PMID:23319182

  18. Hematopoiesis and Hematopoietic Organs in Arthropods

    PubMed Central

    Grigorian, Melina; Hartenstein, Volker

    2013-01-01

    Hemocytes (blood cells) are motile cells moving throughout the extracellular space and exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species. PMID:23319182

  19. Investigating onychophoran gas exchange and water balance as a means to inform current controversies in arthropod physiology.

    PubMed

    Clusella-Trullas, Susana; Chown, Steven L

    2008-10-01

    Several controversies currently dominate the fields of arthropod metabolic rate, gas exchange and water balance, including the extent to which modulation of gas exchange reduces water loss, the origins of discontinuous gas exchange, the relationship between metabolic rate and life-history strategies, and the causes of Palaeozoic gigantism. In all of these areas, repeated calls have been made for the investigation of groups that might most inform the debates, especially of taxa in key phylogenetic positions. Here we respond to this call by investigating metabolic rate, respiratory water loss and critical oxygen partial pressure (Pc) in the onychophoran Peripatopsis capensis, a member of a group basal to the arthropods, and by synthesizing the available data on the Onychophora. The rate of carbon dioxide release (VCO2) at 20 degrees C in P. capensis is 0.043 ml CO2 h(-1), in keeping with other onychophoran species; suggesting that low metabolic rates in some arthropod groups are derived. Continuous gas exchange suggests that more complex gas exchange patterns are also derived. Total water loss in P. capensis is 57 mg H2O h(-1) at 20 degrees C, similar to modern estimates for another onychophoran species. High relative respiratory water loss rates ( approximately 34%; estimated using a regression technique) suggest that the basal condition in arthropods may be a high respiratory water loss rate. Relatively high Pc values (5-10% O2) suggest that substantial safety margins in insects are also a derived condition. Curling behaviour in P. capensis appears to be a strategy to lower energetic costs when resting, and the concomitant depression of water loss is a proximate consequence of this behaviour. PMID:18805813

  20. Sweeping beauty: is grassland arthropod community composition effectively estimated by sweep netting?

    PubMed Central

    Spafford, Ryan D; Lortie, Christopher J

    2013-01-01

    Arthropods are critical ecosystem components due to their high diversity and sensitivity to perturbation. Furthermore, due to their ease of capture they are often the focus of environmental health surveys. There is much debate regarding the best sampling method to use in these surveys. Sweep netting and pan trapping are two sampling methods commonly used in agricultural arthropod surveys, but have not been contrasted in natural grassland systems at the community level. The purpose of this study was to determine whether sweep netting was effective at estimating arthropod diversity at the community level in grasslands or if supplemental pan trapping was needed. Arthropods were collected from grassland sites in Montana, USA, in the summer of 2011. The following three standardized evaluation criteria (consistency, reliability, and precision) were developed to assess the efficacy of sweep netting and pan trapping, based on analyses of variations in arthropod abundances, species richness, evenness, capture frequency, and community composition. Neither sampling method was sufficient in any criteria to be used alone for community-level arthropod surveys. On a taxa-specific basis, however, sweep netting was consistent, reliable, and precise for Thysanoptera, infrequently collected (i.e., rare) insects, and Arachnida, whereas pan trapping was consistent, reliable, and precise for Collembola and bees, which is especially significant given current threats to the latter's populations worldwide. Species-level identifications increase the detected dissimilarity between sweep netting and pan trapping. We recommend that community-level arthropod surveys use both sampling methods concurrently, at least in grasslands, but likely in most nonagricultural systems. Target surveys, such as monitoring bee communities in fragmented grassland habitat or where detailed information on behavior of the target arthropod groups is available can in some instances employ singular methods. As a

  1. Household Arthropod Allergens in Korea

    PubMed Central

    Jeong, Kyoung Yong

    2009-01-01

    Arthropods are important in human health, which can transmit pathogens to humans, parasitize, or produce important allergens. Allergy prevalence becomes higher in Korea recently as well as other developed countries in contrast to a decrease of infectious diseases. Allergic diseases caused by household arthropods have increased dramatically during the last few decades since human beings spend more their time for indoor activities in modernized life style. Household arthropods are one of the most common causes of allergic diseases. Biological characterization of household arthropods and researches on their allergens will provide better understanding of the pathogenesis of allergic diseases and suggest new therapeutic ways. Therefore, studies on arthropods of allergenic importance can be considered one of the major research areas in medical arthropodology and parasitology. Here, the biology of several household arthropods, including house dust mites and cockroaches, the 2 most well known arthropods living indoor together with humans worldwide, and characteristics of their allergens, especially the research activities on these allergens performed in Korea, are summarized. PMID:19885330

  2. Arthropod-borne bacterial diseases in pregnancy.

    PubMed

    Dotters-Katz, Sarah K; Kuller, Jeffrey; Heine, R Phillips

    2013-09-01

    Arthropod-borne bacterial diseases affect more than 25,000 Americans every year and thousands more around the world. These infections present a diagnostic dilemma for clinicians because they mimic many other pathologic conditions and are often low on or absent from the differential diagnosis list. Diagnosis is particularly challenging during pregnancy, as these infections may mimic common pregnancy-specific conditions, such as typical and atypical preeclampsia, or symptoms of pregnancy itself. Concerns regarding the safety in pregnancy of some indicated antibiotics add a therapeutic challenge for the prescriber, requiring knowledge of alternative therapeutic options for many arthropod-borne bacterial diseases. Physicians, especially those in endemic areas, must keep this class of infections in mind, particularly when the presentation does not appear classic for more commonly seen conditions. This article discusses presentation, diagnosis, and treatment of the most common of these arthropod-borne bacterial diseases, including Lyme disease, Rocky Mountain spotted fever, tick-borne relapsing fever, typhus, plague, cat-scratch disease, and Carrión disease. PMID:25102120

  3. Laboratory Identification of Arthropod Ectoparasites

    PubMed Central

    Pritt, Bobbi S.

    2014-01-01

    SUMMARY The collection, handling, identification, and reporting of ectoparasitic arthropods in clinical and reference diagnostic laboratories are discussed in this review. Included are data on ticks, mites, lice, fleas, myiasis-causing flies, and bed bugs. The public health importance of these organisms is briefly discussed. The focus is on the morphological identification and proper handling and reporting of cases involving arthropod ectoparasites, particularly those encountered in the United States. Other arthropods and other organisms not of public health concern, but routinely submitted to laboratories for identification, are also briefly discussed. PMID:24396136

  4. Laboratory identification of arthropod ectoparasites.

    PubMed

    Mathison, Blaine A; Pritt, Bobbi S

    2014-01-01

    The collection, handling, identification, and reporting of ectoparasitic arthropods in clinical and reference diagnostic laboratories are discussed in this review. Included are data on ticks, mites, lice, fleas, myiasis-causing flies, and bed bugs. The public health importance of these organisms is briefly discussed. The focus is on the morphological identification and proper handling and reporting of cases involving arthropod ectoparasites, particularly those encountered in the United States. Other arthropods and other organisms not of public health concern, but routinely submitted to laboratories for identification, are also briefly discussed. PMID:24396136

  5. Arthropod Distribution in a Tropical Rainforest: Tackling a Four Dimensional Puzzle

    PubMed Central

    Basset, Yves; Cizek, Lukas; Cuénoud, Philippe; Didham, Raphael K.; Novotny, Vojtech; Ødegaard, Frode; Roslin, Tomas; Tishechkin, Alexey K.; Schmidl, Jürgen; Winchester, Neville N.; Roubik, David W.; Aberlenc, Henri-Pierre; Bail, Johannes; Barrios, Héctor; Bridle, Jonathan R.; Castaño-Meneses, Gabriela; Corbara, Bruno; Curletti, Gianfranco; Duarte da Rocha, Wesley; De Bakker, Domir; Delabie, Jacques H. C.; Dejean, Alain; Fagan, Laura L.; Floren, Andreas; Kitching, Roger L.; Medianero, Enrique; Gama de Oliveira, Evandro; Orivel, Jérôme; Pollet, Marc; Rapp, Mathieu; Ribeiro, Sérvio P.; Roisin, Yves; Schmidt, Jesper B.; Sørensen, Line; Lewinsohn, Thomas M.; Leponce, Maurice

    2015-01-01

    Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2km of distance, 40m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods. PMID:26633187

  6. Arthropod Distribution in a Tropical Rainforest: Tackling a Four Dimensional Puzzle.

    PubMed

    Basset, Yves; Cizek, Lukas; Cuénoud, Philippe; Didham, Raphael K; Novotny, Vojtech; Ødegaard, Frode; Roslin, Tomas; Tishechkin, Alexey K; Schmidl, Jürgen; Winchester, Neville N; Roubik, David W; Aberlenc, Henri-Pierre; Bail, Johannes; Barrios, Héctor; Bridle, Jonathan R; Castaño-Meneses, Gabriela; Corbara, Bruno; Curletti, Gianfranco; Duarte da Rocha, Wesley; De Bakker, Domir; Delabie, Jacques H C; Dejean, Alain; Fagan, Laura L; Floren, Andreas; Kitching, Roger L; Medianero, Enrique; Gama de Oliveira, Evandro; Orivel, Jérôme; Pollet, Marc; Rapp, Mathieu; Ribeiro, Sérvio P; Roisin, Yves; Schmidt, Jesper B; Sørensen, Line; Lewinsohn, Thomas M; Leponce, Maurice

    2015-01-01

    Quantifying the spatio-temporal distribution of arthropods in tropical rainforests represents a first step towards scrutinizing the global distribution of biodiversity on Earth. To date most studies have focused on narrow taxonomic groups or lack a design that allows partitioning of the components of diversity. Here, we consider an exceptionally large dataset (113,952 individuals representing 5,858 species), obtained from the San Lorenzo forest in Panama, where the phylogenetic breadth of arthropod taxa was surveyed using 14 protocols targeting the soil, litter, understory, lower and upper canopy habitats, replicated across seasons in 2003 and 2004. This dataset is used to explore the relative influence of horizontal, vertical and seasonal drivers of arthropod distribution in this forest. We considered arthropod abundance, observed and estimated species richness, additive decomposition of species richness, multiplicative partitioning of species diversity, variation in species composition, species turnover and guild structure as components of diversity. At the scale of our study (2 km of distance, 40 m in height and 400 days), the effects related to the vertical and seasonal dimensions were most important. Most adult arthropods were collected from the soil/litter or the upper canopy and species richness was highest in the canopy. We compared the distribution of arthropods and trees within our study system. Effects related to the seasonal dimension were stronger for arthropods than for trees. We conclude that: (1) models of beta diversity developed for tropical trees are unlikely to be applicable to tropical arthropods; (2) it is imperative that estimates of global biodiversity derived from mass collecting of arthropods in tropical rainforests embrace the strong vertical and seasonal partitioning observed here; and (3) given the high species turnover observed between seasons, global climate change may have severe consequences for rainforest arthropods. PMID:26633187

  7. Tiny individuals attached to a new Silurian arthropod suggest a unique mode of brood care.

    PubMed

    Briggs, Derek E G; Siveter, Derek J; Siveter, David J; Sutton, Mark D; Legg, David

    2016-04-19

    The ∼430-My-old Herefordshire, United Kingdom, Lagerstätte has yielded a diversity of remarkably preserved invertebrates, many of which provide fundamental insights into the evolutionary history and ecology of particular taxa. Here we report a new arthropod with 10 tiny arthropods tethered to its tergites by long individual threads. The head of the host, which is covered by a shield that projects anteriorly, bears a long stout uniramous antenna and a chelate limb followed by two biramous appendages. The trunk comprises 11 segments, all bearing limbs and covered by tergites with long slender lateral spines. A short telson bears long parallel cerci. Our phylogenetic analysis resolves the new arthropod as a stem-group mandibulate. The evidence suggests that the tethered individuals are juveniles and the association represents a complex brooding behavior. Alternative possibilities-that the tethered individuals represent a different epizoic or parasitic arthropod-appear less likely. PMID:27044103

  8. Arthropod eyes: The early Cambrian fossil record and divergent evolution of visual systems.

    PubMed

    Strausfeld, Nicholas J; Ma, Xiaoya; Edgecombe, Gregory D; Fortey, Richard A; Land, Michael F; Liu, Yu; Cong, Peiyun; Hou, Xianguang

    2016-03-01

    Four types of eyes serve the visual neuropils of extant arthropods: compound retinas composed of adjacent facets; a visual surface populated by spaced eyelets; a smooth transparent cuticle providing inwardly directed lens cylinders; and single-lens eyes. The first type is a characteristic of pancrustaceans, the eyes of which comprise lenses arranged as hexagonal or rectilinear arrays, each lens crowning 8-9 photoreceptor neurons. Except for Scutigeromorpha, the second type typifies Myriapoda whose relatively large eyelets surmount numerous photoreceptive rhabdoms stacked together as tiers. Scutigeromorph eyes are facetted, each lens crowning some dozen photoreceptor neurons of a modified apposition-type eye. Extant chelicerate eyes are single-lensed except in xiphosurans, whose lateral eyes comprise a cuticle with a smooth outer surface and an inner one providing regular arrays of lens cylinders. This account discusses whether these disparate eye types speak for or against divergence from one ancestral eye type. Previous considerations of eye evolution, focusing on the eyes of trilobites and on facet proliferation in xiphosurans and myriapods, have proposed that the mode of development of eyes in those taxa is distinct from that of pancrustaceans and is the plesiomorphic condition from which facetted eyes have evolved. But the recent discovery of enormous regularly facetted compound eyes belonging to early Cambrian radiodontans suggests that high-resolution facetted eyes with superior optics may be the ground pattern organization for arthropods, predating the evolution of arthrodization and jointed post-protocerebral appendages. Here we provide evidence that compound eye organization in stem-group euarthropods of the Cambrian can be understood in terms of eye morphologies diverging from this ancestral radiodontan-type ground pattern. We show that in certain Cambrian groups apposition eyes relate to fixed or mobile eyestalks, whereas other groups reveal concomitant

  9. Arthropod use of invertebrate carrion

    SciTech Connect

    Seastedt, T.R.; Mameli, L.; Gridley, K.

    1981-01-01

    Arthropods associated with cricket carcasses placed on top and within deciduous forest litter were collected for 12 months. Vespid wasps and ants quickly removed carcasses left on top of forest litter, but carcasses placed within litter persisted throughout the study. Major consumers of carcasses in litter varied seasonally; maggots dominated on fresh carcasses in summer, but fresh carcasses placed in litter in autumn were consumed by other arthropods. A gamasid mite, Hypoaspis (Laelaspis) johnieae, dominated the microarthropod fauna found on exoskeleton fragments. A method for collecting invertebrate carrion feeders and measuring carrion disappearance is presented. 15 references, 2 tables.

  10. Arthropod use of invertebrate carrion

    SciTech Connect

    Seastedt, T.R.; Mameli, L.; Gridley, K.

    1980-08-01

    Arthropods associated with cricket carcasses placed on top and within deciduous forest litter were collected over a 12 month interval. Vespid wasps and ants quickly removed carcasses left on top of forest litter, but carcasses placed within litter persisted throughout the study. Major consumers of carcasses in litter varied seasonally; maggots dominated on fresh carcasses in summer, but fresh carcasses placed in litter in autumn were consumed by other arthropods. A gamasid mite, Hypoaspis (Laelaspis) johnieae dominated the microarthropod fauna found on exoskeleton fragments. A method for collecting invertebrate carrion feeders and measuring carrion disappearance is presented.

  11. Density-Dependent Effects of an Invasive Ant on a Ground-Dwelling Arthropod Community.

    PubMed

    Cooling, M; Sim, D A; Lester, P J

    2015-02-01

    It is frequently assumed that an invasive species that is ecologically or economically damaging in one region, will typically be so in other environments. The Argentine ant Linepithema humile (Mayr) is listed among the world's worst invaders. It commonly displaces resident ant species where it occurs at high population densities, and may also reduce densities of other ground-dwelling arthropods. We investigated the effect of varying Argentine ant abundance on resident ant and nonant arthropod species richness and abundance in seven cities across its range in New Zealand. Pitfall traps were used to compare an invaded and uninvaded site in each city. Invaded sites were selected based on natural varying abundance of Argentine ant populations. Argentine ant density had a significant negative effect on epigaeic ant abundance and species richness, but hypogaeic ant abundance and species richness was unaffected. We observed a significant decrease in Diplopoda abundance with increasing Argentine ant abundance, while Coleoptera abundance increased. The effect on Amphipoda and Isopoda depended strongly on climate. The severity of the impact on negatively affected taxa was reduced in areas where Argentine ant densities were low. Surprisingly, Argentine ants had no effect on the abundance of the other arthropod taxa examined. Morphospecies richness for all nonant arthropod taxa was unaffected by Argentine ant abundance. Species that are established as invasive in one location therefore cannot be assumed to be invasive in other locations based on presence alone. Appropriate management decisions should reflect this knowledge. PMID:26308805

  12. Ex-ante determination of the capacity of field tests to detect effects of genetically modified corn on nontarget arthropods.

    PubMed

    Comas, J; Lumbierres, B; Pons, X; Albajes, R

    2013-08-01

    Field trials may be required to assess risks of genetically modified crops (GMCs) for nontarget arthropods. One critical point of these trials is their capacity to detect differences between the density of one taxon in the GMC and that in the comparator. The detection capacity of a trial depends on the abundance and variability of the taxon, the values assumed for type I (alpha) and II (beta) errors, and the characteristics of the trial and statistical design. To determine the optimal trial layout and statistical analysis, 20 field trials carried out in Spain from 2000 to 2009 to assess risks of GMCs on nontarget arthropods were examined with alpha and beta fixed at 0.05 and 0.20, respectively. Under the experimental conditions tested, taxon variability is the most influential component determining test detection capacity; the maximum acceptable values of taxon variability to achieve a certain detection capacity were calculated for different numbers of replicates (blocks), treatments, and years. A close relationship between taxon variability and mean abundance in visual counts, pitfall traps, and yellow sticky traps allowed minimal critical abundance thresholds to be estimated to guarantee a certain detection capacity and to establish abundance criteria for selecting focal taxa. The number of replications (blocks), treatments, sites, and years has a lesser influence on detection capacity once minimal values in taxon abundance in field trials are ensured. Conclusions reached on the detection capacity of field trials with the experimental data obtained under Mediterranean conditions should be contrasted with those of other regions. PMID:24020279

  13. Carnivorous arthropods after spring flood

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spring flooding is a common practice in Wisconsin cranberries, but flooding as insect control produces variable results among marshes. This project is aimed at figuring out why it works, and why it sometimes doesn’t. We have focused on tracking arthropod populations to explain the observed patterns ...

  14. Preliminary observations of arthropods associated with buried carrion on Oahu.

    PubMed

    Rysavy, Noel M; Goff, M Lee

    2015-03-01

    Several studies in Hawaii have focused on arthropod succession and decomposition patterns of surface remains, but the current research presents the first study to focus on shallow burials in this context. Three domestic pig carcasses (Sus scrofa L.) were buried at the depths of 20-40 cm in silty clay loam soil on an exposed ridge on the leeward side of the volcanically formed Koolau Mountain Range. One carcass was exhumed after 3 weeks, another after 6 weeks, and the last carcass was exhumed after 9 weeks. An inventory of arthropod taxa present on the carrion and in the surrounding soil and observations pertaining to decomposition were recorded at each exhumation. The longer the carrion was buried, the greater the diversity of arthropod species that were recovered from the remains. Biomass loss was calculated to be 49% at the 3-week interval, 56% at the 6-week interval, and 59% at the 9-week interval. PMID:25413711

  15. Bioinformatic prediction of arthropod/nematode-like peptides in non-arthropod, non-nematode members of the Ecdysozoa.

    PubMed

    Christie, Andrew E; Nolan, Daniel H; Garcia, Zachery A; McCoole, Matthew D; Harmon, Sarah M; Congdon-Jones, Benjamin; Ohno, Paul; Hartline, Niko; Congdon, Clare Bates; Baer, Kevin N; Lenz, Petra H

    2011-02-01

    The Onychophora, Priapulida and Tardigrada, along with the Arthropoda, Nematoda and several other small phyla, form the superphylum Ecdysozoa. Numerous peptidomic studies have been undertaken for both the arthropods and nematodes, resulting in the identification of many peptides from each group. In contrast, little is known about the peptides used as paracrines/hormones by species from the other ecdysozoan taxa. Here, transcriptome mining and bioinformatic peptide prediction were used to identify peptides in members of the Onychophora, Priapulida and Tardigrada, the only non-arthropod, non-nematode members of the Ecdysozoa for which there are publicly accessible expressed sequence tags (ESTs). The extant ESTs for each phylum were queried using 106 arthropod/nematode peptide precursors. Transcripts encoding calcitonin-like diuretic hormone and pigment-dispersing hormone (PDH) were identified for the onychophoran Peripatopsis sedgwicki, with transcripts encoding C-type allatostatin (C-AST) and FMRFamide-like peptide identified for the priapulid Priapulus caudatus. For the Tardigrada, transcripts encoding members of the A-type allatostatin, C-AST, insect kinin, orcokinin, PDH and tachykinin-related peptide families were identified, all but one from Hypsibius dujardini (the exception being a Milnesium tardigradum orcokinin-encoding transcript). The proteins deduced from these ESTs resulted in the prediction of 48 novel peptides, six onychophoran, eight priapulid and 34 tardigrade, which are the first described from these phyla. PMID:21074533

  16. Changes in arthropod assemblages along a wide gradient of disturbance in Gabon.

    PubMed

    Basset, Yves; Missa, Olivier; Alonso, Alfonso; Miller, Scott E; Curletti, Gianfranco; De Meyer, Marc; Eardley, Connal; Lewis, Owen T; Mansell, Mervyn W; Novotny, Vojtech; Wagner, Thomas

    2008-12-01

    Searching for indicator taxa representative of diverse assemblages, such as arthropods, is an important objective of many conservation studies. We evaluated the impacts of a wide gradient of disturbance in Gabon on a range of arthropod assemblages representing different feeding guilds. We examined 4 x 10(5) arthropod individuals from which 21 focal taxa were separated into 1534 morphospecies. Replication included the understory of 3 sites in each of 4 different stages of forest succession and land use (i.e., habitats) after logging (old and young forests, savanna, and gardens). We used 3 complementary sampling methods to survey sites throughout the year. Overall differences in arthropod abundance and diversity were greatest between forest and open habitats, and cleared forest invaded by savanna had the lowest abundance and diversity. The magnitude of faunal differences was much smaller between old and young forests. When considered at this local scale, anthropogenic modification of habitats did not result in a monotonous decline of diversity because many herbivore pests and their associated predators and parasitoids were abundant and diverse in gardens, where plant productivity was kept artificially high year-round through watering and crop rotation. We used a variety of response variables to measure the strength of correlations across survey locations among focal taxa. These could be ranked as follows in terms of decreasing number of significant correlations: species turnover > abundance > observed species richness > estimated species richness > percentage of site-specific species. The number of significant correlations was generally low and apparently unrelated to taxonomy or guild structure. Our results emphasize the value of reporting species turnover in conservation studies, as opposed to simply measuring species richness, and that the search for indicator taxa is elusive in the tropics. One promising alternative might be to consider "predictor sets" of a

  17. The role of wrack deposits for supralittoral arthropods: An example using Atlantic sandy beaches of Brazil and Spain

    NASA Astrophysics Data System (ADS)

    Ruiz-Delgado, Mª Carmen; Vieira, Jenyffer Vierheller; Veloso, Valéria Gomes; Reyes-Martínez, Mª José; Sallorenzo, Ilana Azevedo; Borzone, Carlos Alberto; Sánchez-Moyano, Juan Emilio; García García, Francisco José

    2014-01-01

    Wrack deposits, as accumulated detritus, are a common feature on beaches worldwide and significantly contribute to the shaping of supralittoral arthropod communities. The composition and relative age of upper-shore deposits influence the structure and taxonomic composition of invertebrate assemblages. Moreover, these influences may vary geographically, depending on the locally prevailing climatic and hydrodynamic conditions. The amount and composition of wrack deposits as well as community attributes (total density, species richness and diversity) were determined on sandy beaches in three distinct geographical regions: South (Paraná) and Southeast (Rio de Janeiro) of Brazil and SW Spain. These parameters were compared between upper and lower wrack bands on each beach and between beaches in each region. Wrack deposits were composed of mangrove propagules in the Paraná region, by macrophytes, dead invertebrates and macroalgae in Rio de Janeiro region and by seagrass and macroalgae in the SW Spain region. In all regions, the total amount of stranded wrack differed between beaches, but the amount accumulated between bands (i.e upper and lower band) was similar between beaches. Wrack bands shaped the density of common taxa (Talitridae, Tenebrionidae, and Staphylinidae), with consequences for community structures. This result could be due to their preference for specific microhabitats and food sources, which might differ according to the relative age of the wrack deposits. The results suggest that, independent of wrack composition, the distribution of wrack deposits in bands and their relative ages seems to play a role on the structure of supralittoral arthropod assemblages.

  18. Tiny individuals attached to a new Silurian arthropod suggest a unique mode of brood care

    NASA Astrophysics Data System (ADS)

    Briggs, Derek E. G.; Siveter, Derek J.; Siveter, David J.; Sutton, Mark D.

    2016-04-01

    The ˜430-My-old Herefordshire, United Kingdom, Lagerstätte has yielded a diversity of remarkably preserved invertebrates, many of which provide fundamental insights into the evolutionary history and ecology of particular taxa. Here we report a new arthropod with 10 tiny arthropods tethered to its tergites by long individual threads. The head of the host, which is covered by a shield that projects anteriorly, bears a long stout uniramous antenna and a chelate limb followed by two biramous appendages. The trunk comprises 11 segments, all bearing limbs and covered by tergites with long slender lateral spines. A short telson bears long parallel cerci. Our phylogenetic analysis resolves the new arthropod as a stem-group mandibulate. The evidence suggests that the tethered individuals are juveniles and the association represents a complex brooding behavior. Alternative possibilities—that the tethered individuals represent a different epizoic or parasitic arthropod—appear less likely.

  19. Quantitative phase imaging of arthropods

    NASA Astrophysics Data System (ADS)

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-11-01

    Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy.

  20. Quantitative phase imaging of arthropods

    PubMed Central

    Sridharan, Shamira; Katz, Aron; Soto-Adames, Felipe; Popescu, Gabriel

    2015-01-01

    Abstract. Classification of arthropods is performed by characterization of fine features such as setae and cuticles. An unstained whole arthropod specimen mounted on a slide can be preserved for many decades, but is difficult to study since current methods require sample manipulation or tedious image processing. Spatial light interference microscopy (SLIM) is a quantitative phase imaging (QPI) technique that is an add-on module to a commercial phase contrast microscope. We use SLIM to image a whole organism springtail Ceratophysella denticulata mounted on a slide. This is the first time, to our knowledge, that an entire organism has been imaged using QPI. We also demonstrate the ability of SLIM to image fine structures in addition to providing quantitative data that cannot be obtained by traditional bright field microscopy. PMID:26334858

  1. Visual orientation and navigation in nocturnal arthropods.

    PubMed

    Warrant, Eric; Dacke, Marie

    2010-01-01

    With their highly sensitive visual systems, the arthropods have evolved a remarkable capacity to orient and navigate at night. Whereas some navigate under the open sky, and take full advantage of the celestial cues available there, others navigate in more difficult conditions, such as through the dense understory of a tropical rainforest. Four major classes of orientation are performed by arthropods at night, some of which involve true navigation (i.e. travel to a distant goal that lies beyond the range of direct sensory contact): (1) simple straight-line orientation, typically for escape purposes; (2) nightly short-distance movements relative to a shoreline, typically in the context of feeding; (3) long-distance nocturnal migration at high altitude in the quest to locate favorable feeding or breeding sites, and (4) nocturnal excursions to and from a fixed nest or food site (i.e. homing), a task that in most species involves path integration and/or the learning and recollection of visual landmarks. These four classes of orientation--and their visual basis--are reviewed here, with special emphasis given to the best-understood animal systems that are representative of each. PMID:20733292

  2. Longleaf Pine Characterists Associated with Arthropods Available for Red-Cockaded Woodpeckers

    SciTech Connect

    Hanula, J.L.; Franzreb, K.E.; Pepper, W.D.

    1999-01-25

    The authors sampled arthropods on 300 longleaf pine under varying stand conditions and ranging in age from 20 to 100 years. The most diverse orders were beetles, spiders, ants, wasps and bees. The most abundant were aphids and Hymenoptera with a large number of ants. Arthropod biomass per tree increased in age up to 65-70 years, but biomass was highest in the youngest stands. Arthropods were positively correlated to bark thickness and tree diameter, but negatively related to the stand basal area. No relationships were found between abundance and ground vegetation conditions.

  3. Arthropods, plants and transmission lines in Arizona: community dynamics during secondary succession in a desert grassland

    SciTech Connect

    Butt, S.M.; Beley, J.R.; Ditsworth, T.M.; Johnson, C.D.; Balda, R.P.

    1980-11-01

    In 1972, access roads were constructed and then used by heavy equipment to build a 500 kV powerline in north central Arizona. Secondary succession of arthropods was studied till 1977 by comparing the initially bare soil of the roads with undisturbed control plots nearby. It was found that, after construction, total anthropod densities were reduced for two to three years, that after five years no anthropod taxa had greater densities on the disturbed areas, but some were significantly reduced, the diversity of arthropods dropped for a period of three or four years, that arthropod community similarity of the two study plots appeared to be related to total cover of plants and similarity of plant communities, the significant correlations between arthropod taxa suggested that the plant communities of the two plots are close in successional status, plant succession was not as rapid as expected, and the disturbed area had a great reduction in perennial grasses but an increase in annual herbs. The numerical dominance of herbivores on both disturbed and control plots, especially after construction, supports the hypothesis that linear, predominantly grazing food chains are characteristic of early successional stages.

  4. Arthropods, plants, and transmission lines in Arizona: secondary succession in a Sonoran Desert habitat

    SciTech Connect

    Johnson, C.D.; Ditsworth, T.M.; Beley, J.R.

    1981-09-01

    Overall arthropod densities were low at this site, but the arthropod densities on the disturbed areas appeared to be enhanced after several years. No taxa were found to be statistically different in density between control and disturbed plots. Diversity decreased on the disturbed area after construction. Arthropod community similarity (C) was lower after construction, but C values appear to be related to presence or absence of annual herbs and grasses and not to total cover. Except for globe mallow, there were no pioneer plant species on the experimental plot. Effects of powerline construction on the experimental plant community were a brief reduction in total cover and a slight increase in cover of herbs and annual grasses. The 1976 and 1977 samples exhibit comparable cover values of these plants on both experimental and control plots. The dominant arthropod taxa on the experimental area (especially Thysanoptera, Cicadellidae, Coccinellidae, and Melyridae) appear to be responding numerically to the annual herbs and grasses which are becoming established on the plot.

  5. Multi-taxa trait and functional responses to physical disturbance.

    PubMed

    Pedley, Scott M; Dolman, Paul M

    2014-11-01

    Examining assemblage trait responses to environmental stressors extends our understanding beyond patterns of taxonomic diversity and composition, with results potentially transferable among bioregions. But the degree to which trait responses may be generalized across taxonomic groups remains incompletely understood. We compared trait responses among carabids, spiders and plants to an experimentally manipulated gradient of physical disturbance, replicated in open habitats within a forested landscape. Recolonization of recently disturbed habitats is expected to favour species with traits that promote greater dispersal ability, independent of taxa. We specifically predicted that physical disturbance would increase the representation of carabids with smaller body size, wings or wing dimorphism, spiders able to disperse aerially, and plants with therophyte life-history and wind-dispersed seed. We sampled 197 arthropod species (14,738 individuals) and 164 species of plant. The strength of association between each trait and the disturbance intensity was quantified by correlating matrices of species by traits, species abundance by sites and sites by environment, with significance assessed by comparison with a null model. Responses of biological traits varied among taxa but could be consistently interpreted in terms of dispersal ability. Trait shifts for carabid and plant assemblages were as predicted and correspond to those observed in other disturbance regimes. Assemblages after disturbance comprised smaller and winged carabids, and smaller plants with wind-dispersed seed, consistent with selection for species with better dispersal ability. In contrast, aerial dispersal did not appear important in spider recolonization, instead terrestrial dispersal ability was suggested by the increased abundance of larger-bodied and cursorial species. However, larger spider body size was also associated with an active-hunting strategy, also favoured in the post-disturbance environment

  6. Early land animals in north america: evidence from devonian age arthropods from gilboa, new york.

    PubMed

    Shear, W A; Bonamo, P M; Grierson, J D; Rolfe, W D; Smith, E L; Norton, R A

    1984-05-01

    A new fossil site near Gilboa, New York, is one of only three where fossils of terrestrial arthropods of Devonian age have been found. The new Gilboan fauna is younger than the other two but richer in taxa. Fragmentary remains and nearly whole specimens assigned to Eurypterida, Arachnida (Trigonotarbida, Araneae, Amblypygi, and Acari), Chilopoda [Craterostigmatomorpha(?) and Scuterigeromorpha(?)], and tentatively to Insecta (Archaeognatha) have been found. The centipedes and possible insects may represent the earliest records known for these groups. PMID:17753774

  7. Impact of chemically contaminated sewage sludge on the collard arthropod community

    SciTech Connect

    Culliney, T.W.; Pimentel, D.; Lisk, D.J.

    1986-08-01

    Stress effects on a terrestrial arthropod community were evident in a study of collards grown in soil amended with chemically contaminated sewage sludge. Plant growth in the contaminated sludge was significantly reduced compared with growth in plots treated with relatively uncontaminated sludge from two small towns or with mature alone. Population densities of major arthropod taxa tended to be lower in plots of contaminated sludge than they were in uncontaminated sludge and manure plots. Species richness and diversity were also reduced in contaminated-sludge plots compared with those of uncontaminated sludge and manure treatments. In general, few differences were observed in plant growth and arthropod numbers between the uncontaminated-sludge treatment, or uncontaminated sludge treated with cadmium or with the insecticide dieldrin. Because cadmium and dieldrin were applied at dosages of cadmium and polychlorinated biphenyls (PCB's) found in the contaminated sludge, results suggested that these two toxins were not responsible for the effects on plants and arthropods observed in the contaminated-sludge treatment. Results of this study indicated the potential for sludge-borne contaminants to suppress growth in crop plants and reduce abundance of their associated arthropods.

  8. Knowledge of Arthropod Carnivory and Herbivory: Factors Influencing Preservice Elementary Teacher's Attitudes and Beliefs toward Arthropods

    ERIC Educational Resources Information Center

    Wagler, Ron; Wagler, Amy

    2013-01-01

    Human negativity toward arthropods has been well documented but the factors that contribute to this negativity have been elusive. This study explored knowledge of arthropod carnivory and herbivory as possible casual factors that contribute to the negative tendencies preservice elementary teachers have toward most arthropods. Specifically, this…

  9. A novel stress distribution organ in the arthropod exoskeleton.

    PubMed

    Hecht, Emelia M; Cullinane, Dennis M; Grosse, Ian R

    2010-09-01

    and 4% greater equivalent strain. The model with the struts is capable of withstanding an applied physiological load of up to 16.6 N prior to buckling, more than twice that of the model without struts (7.8 N). We suggest that this novel arthropod strut system is likely utilized at many joint surfaces at locations of high skeletal stress concentrations, is an adaptation for minimizing skeletal failure via localized buckling, and may be present in other arthropod taxa. PMID:20478397

  10. Representative taxa in field trials for environmental risk assessment of genetically modified maize.

    PubMed

    Albajes, R; Lumbierres, B; Pons, X; Comas, J

    2013-12-01

    When assessing the benefits and risks of transgenic crops, one consideration is their relative effects on non-target arthropod (NTA) abundance and functions within agroecosystems. Several laboratory and field trials have been conducted in Spain since the late 1990s to assess this issue. A consideration in the design of field trials is whether it is necessary to sample most NTAs living in the crop or only representative taxa that perform main ecological functions and have a good capacity to detect small changes in their abundance. Small changes in the field abundance of an effective representative taxon should be detectable using standard experimental protocols. The ability of a species to reveal differences across treatments may be analysed by examining the detectable treatment effects for surveyed non-target organisms. Analysis of data from several NTAs recorded in 14 field trials conducted over 10 years using complete block designs allowed us to select a number of representative taxa capable of detecting changes in the density or activity of arthropod herbivores, predators, parasitoids and decomposers in transgenic and non-transgenic maize varieties. The most suitable NTA as representative taxa (with detectable treatment effects below 50%) included leafhoppers among arthropod herbivores, Orius spp., Araneae, and Carabidae among predators, chalcidids, particularly the family Mymaridae, among parasitoids and Chloropidae as decomposer. Details of sampling techniques for each sampled taxa and their advantages and disadvantages are discussed. It is concluded that abundance of taxa is the most influential factor determining their capacity to detect changes caused by genetically modified varieties. PMID:23987801

  11. The ontology of biological taxa

    PubMed Central

    Schulz, Stefan; Stenzhorn, Holger; Boeker, Martin

    2008-01-01

    Motivation: The classification of biological entities in terms of species and taxa is an important endeavor in biology. Although a large amount of statements encoded in current biomedical ontologies is taxon-dependent there is no obvious or standard way for introducing taxon information into an integrative ontology architecture, supposedly because of ongoing controversies about the ontological nature of species and taxa. Results: In this article, we discuss different approaches on how to represent biological taxa using existing standards for biomedical ontologies such as the description logic OWL DL and the Open Biomedical Ontologies Relation Ontology. We demonstrate how hidden ambiguities of the species concept can be dealt with and existing controversies can be overcome. A novel approach is to envisage taxon information as qualities that inhere in biological organisms, organism parts and populations. Availability: The presented methodology has been implemented in the domain top-level ontology BioTop, openly accessible at http://purl.org/biotop. BioTop may help to improve the logical and ontological rigor of biomedical ontologies and further provides a clear architectural principle to deal with biological taxa information. Contact: stschulz@uni-freiburg.de PMID:18586729

  12. Drought and arthropod pests of crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water deficit can make otherwise arable regions less, or nonarable, from lack of life-sustaining water and it can also affect the extent to which crops are afflicted by arthropod pests. The effects of drought on host plant availability and nutrititive value influence arthropod pests of crops in a v...

  13. Herbicide drift affects plant and arthropod communities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field edges, old fields, and other semi-natural habitats in agricultural landscapes support diverse plant communities that help sustain pollinators, predators, and other beneficial arthropods. These plant and arthropod communities may be at persistent ecotoxicological risk from herbicides applied to...

  14. Molecular bases of plant resistance to arthropods.

    PubMed

    Smith, C Michael; Clement, Stephen L

    2012-01-01

    Arthropod-resistant crops provide significant ecological and economic benefits to global agriculture. Incompatible interactions involving resistant plants and avirulent pest arthropods are mediated by constitutively produced and arthropod-induced plant proteins and defense allelochemicals synthesized by resistance gene products. Cloning and molecular mapping have identified the Mi-1.2 and Vat arthropod resistance genes as CC-NBS-LRR (coiled coil-nucleotide binding site-leucine rich repeat) subfamily NBS-LRR resistance proteins, as well as several resistance gene analogs. Genetic linkage mapping has identified more than 100 plant resistance gene loci and linked molecular markers used in cultivar development. Rice and sorghum arthropod-resistant cultivars and, to a lesser extent, raspberry and wheat cultivars are components of integrated pest management (IPM) programs in Asia, Australia, Europe, and North America. Nevertheless, arthropod resistance in most food and fiber crops has not been integrated due primarily to the application of synthetic insecticides. Plant and arthropod genomics provide many opportunities to more efficiently develop arthropod-resistant plants, but integration of resistant cultivars into IPM programs will succeed only through interdisciplinary collaboration. PMID:21910639

  15. Measuring Stratigraphic Congruence Across Trees, Higher Taxa, and Time

    PubMed Central

    O'Connor, Anne; Wills, Matthew A.

    2016-01-01

    The congruence between the order of cladistic branching and the first appearance dates of fossil lineages can be quantified using a variety of indices. Good matching is a prerequisite for the accurate time calibration of trees, while the distribution of congruence indices across large samples of cladograms has underpinned claims about temporal and taxonomic patterns of completeness in the fossil record. The most widely used stratigraphic congruence indices are the stratigraphic consistency index (SCI), the modified Manhattan stratigraphic measure (MSM*), and the gap excess ratio (GER) (plus its derivatives; the topological GER and the modified GER). Many factors are believed to variously bias these indices, with several empirical and simulation studies addressing some subset of the putative interactions. This study combines both approaches to quantify the effects (on all five indices) of eight variables reasoned to constrain the distribution of possible values (the number of taxa, tree balance, tree resolution, range of first occurrence (FO) dates, center of gravity of FO dates, the variability of FO dates, percentage of extant taxa, and percentage of taxa with no fossil record). Our empirical data set comprised 647 published animal and plant cladograms spanning the entire Phanerozoic, and for these data we also modeled the effects of mean age of FOs (as a proxy for clade age), the taxonomic rank of the clade, and the higher taxonomic group to which it belonged. The center of gravity of FO dates had not been investigated hitherto, and this was found to correlate most strongly with some measures of stratigraphic congruence in our empirical study (top-heavy clades had better congruence). The modified GER was the index least susceptible to bias. We found significant differences across higher taxa for all indices; arthropods had lower congruence and tetrapods higher congruence. Stratigraphic congruence—however measured—also varied throughout the Phanerozoic

  16. Measuring Stratigraphic Congruence Across Trees, Higher Taxa, and Time.

    PubMed

    O'Connor, Anne; Wills, Matthew A

    2016-09-01

    The congruence between the order of cladistic branching and the first appearance dates of fossil lineages can be quantified using a variety of indices. Good matching is a prerequisite for the accurate time calibration of trees, while the distribution of congruence indices across large samples of cladograms has underpinned claims about temporal and taxonomic patterns of completeness in the fossil record. The most widely used stratigraphic congruence indices are the stratigraphic consistency index (SCI), the modified Manhattan stratigraphic measure (MSM*), and the gap excess ratio (GER) (plus its derivatives; the topological GER and the modified GER). Many factors are believed to variously bias these indices, with several empirical and simulation studies addressing some subset of the putative interactions. This study combines both approaches to quantify the effects (on all five indices) of eight variables reasoned to constrain the distribution of possible values (the number of taxa, tree balance, tree resolution, range of first occurrence (FO) dates, center of gravity of FO dates, the variability of FO dates, percentage of extant taxa, and percentage of taxa with no fossil record). Our empirical data set comprised 647 published animal and plant cladograms spanning the entire Phanerozoic, and for these data we also modeled the effects of mean age of FOs (as a proxy for clade age), the taxonomic rank of the clade, and the higher taxonomic group to which it belonged. The center of gravity of FO dates had not been investigated hitherto, and this was found to correlate most strongly with some measures of stratigraphic congruence in our empirical study (top-heavy clades had better congruence). The modified GER was the index least susceptible to bias. We found significant differences across higher taxa for all indices; arthropods had lower congruence and tetrapods higher congruence. Stratigraphic congruence-however measured-also varied throughout the Phanerozoic, reflecting

  17. Noninsect Arthropods in Popular Music

    PubMed Central

    Coelho, Joseph R.

    2011-01-01

    The occurrence of noninsect arthropods in popular music was examined in order to explore human attitudes toward these species, especially as compared to insects. Crustaceans were the most commonly referenced taxonomic group in artist names, album titles and cover art, followed by spiders and scorpions. The surprising prevalence of crustaceans may be related to the palatability of many of the species. Spiders and scorpions were primarily used for shock value, as well as totemic qualities of strength and ferocity. Spiders were the most abundant group among song titles, perhaps because of their familiarity to the general public. Three noninsect arthropod album titles were found from the early 1970s, then none appear until 1990. Older albums are difficult to find unless they are quite popular, and the resurgence of albums coincides with the rise of the internet. After 1990, issuance of such albums increased approximately linearly. Giant and chimeric album covers were the most common of themes, indicating the use of these animals to inspire fear and surprise. The lyrics of select songs are presented to illustrate the diversity of sentiments present, from camp spookiness to edibility. PMID:26467627

  18. Arthropods affecting the human eye.

    PubMed

    Panadero-Fontán, Rosario; Otranto, Domenico

    2015-02-28

    Ocular infestations by arthropods consist in the parasitization of the human eye, either directly (e.g., some insect larvae causing ophthalmomyiasis) or via arthropods feeding on lachrymal/conjunctival secretions (e.g., some eye-seeking insects, which also act as vectors of eye pathogens). In addition, demodicosis and phthiriasis may also cause eye discomfort in humans. Ophthalmomyiasis by larvae of the families Oestridae, Calliphoridae and Sarcophagidae, are frequent causative agents of human ocular infestations. Over the last decades, the extensive use of macrocyclic lactones in cattle has reduced the frequency of infestations by Hypoderma bovis and Hypoderma lineatum (family Oestridae), and consequently, human infestations by these species. A prompt diagnosis of ocular myiasis (e.g., by serological tests) is pivotal for positive prognoses, particularly when the larvae are not detectable during the ophthalmologic examination. Molecular diagnoses may also assist physicians and parasitologists in achieving time-efficient diagnoses of infestations by Oestridae causing myiasis. Finally, due to widespread international travel to exotic destinations, cases of myiasis are increasing in non-endemic areas, therefore requiring physicians to acquire a profound knowledge of the clinical symptoms linked to these infestations to prevent costly, inappropriate treatments or severe complications. PMID:25620292

  19. Testing the effects of ant invasions on non-ant arthropods with high-resolution taxonomic data.

    PubMed

    Hanna, Cause; Naughton, Ida; Boser, Christina; Holway, David

    2015-10-01

    Invasions give rise to a wide range of ecological effects. Many invasions proceed without noticeable impacts on the resident biota, whereas others shift species composition and even alter ecosystem function. Ant invasions generate a broad spectrum of ecological effects, but controversy surrounds the extent of these impacts, especially with regard to how other arthropods are affected. This uncertainty in part results from the widespread use of low-resolution taxonomic data, which can mask the presence of other introduced species and make it difficult to isolate the effects of ant invasions on native species. Here, we use high-resolution taxonomic data to examine the effects of Argentine ant invasions on arthropods on Santa Cruz Island, California. We sampled arthropods in eight pairs of invaded and uninvaded plots and then collaborated with taxonomic experts to identify taxa in four focal groups: spiders, bark lice, beetles, and ants. Spiders, bark lice, and beetles made up ~40% of the 9868 non-ant arthropod individuals sampled; the majority of focal group arthropods were putatively native taxa. Although our results indicate strong negative effects of the Argentine ant on native ants, as is well documented, invaded and uninvaded plots did not differ with respect to the richness, abundance, or species composition of spiders, bark lice, and beetles. One common, introduced species of bark louse was more common in uninvaded plots than in invaded plots, and including this species into our analyses changed the relationship between bark louse richness vs. L. humile abundance from no relationship to a significant negative relationship. This case illustrates how failure to differentiate native and introduced taxa can lead to erroneous conclusions about the effects of ant invasions. Our results caution against unqualified assertions about the effects of ant invasions on non-ant arthropods, and more generally demonstrate that accurate assessments of invasion impacts depend on

  20. Factors affecting the abundance of leaf-litter arthropods in unburned and thrice-burned seasonally-dry Amazonian forests.

    PubMed

    Silveira, Juliana M; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-01-01

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae). In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance. PMID:20877720

  1. Factors Affecting the Abundance of Leaf-Litter Arthropods in Unburned and Thrice-Burned Seasonally-Dry Amazonian Forests

    PubMed Central

    Silveira, Juliana M.; Barlow, Jos; Louzada, Julio; Moutinho, Paulo

    2010-01-01

    Fire is frequently used as a land management tool for cattle ranching and annual crops in the Amazon. However, these maintenance fires often escape into surrounding forests, with potentially severe impacts for forest biodiversity. We examined the effect of experimental fires on leaf-litter arthropod abundance in a seasonally-dry forest in the Brazilian Amazon. The study plots (50 ha each) included a thrice-burned forest and an unburned control forest. Pitfall-trap samples were collected at 160 randomly selected points in both plots, with sampling stratified across four intra-annual replicates across the dry and wet seasons, corresponding to 6, 8, 10 and 12 months after the most recent fire. Arthropods were identified to the level of order (separating Formicidae). In order to better understand the processes that determine arthropod abundance in thrice-burned forests, we measured canopy openness, understory density and litter depth. All arthropod taxa were significantly affected by fire and season. In addition, the interactions between burn treatment and season were highly significant for all taxa but Isoptera. The burned plot was characterized by a more open canopy, lower understory density and shallower litter depth. Hierarchical partitioning revealed that canopy openness was the most important factor explaining arthropod order abundances in the thrice-burned plot, whereas all three environmental variables were significant in the unburned control plot. These results reveal the marked impact of recurrent wildfires and seasonality on litter arthropods in this transitional forest, and demonstrate the overwhelming importance of canopy-openness in driving post-fire arthropod abundance. PMID:20877720

  2. Traumatic insemination in terrestrial arthropods.

    PubMed

    Tatarnic, Nikolai J; Cassis, Gerasimos; Siva-Jothy, Michael T

    2014-01-01

    Traumatic insemination is a bizarre form of mating practiced by some invertebrates in which males use hypodermic genitalia to penetrate their partner's body wall during copulation, frequently bypassing the female genital tract and ejaculating into their blood system. The requirements for traumatic insemination to evolve are stringent, yet surprisingly it has arisen multiple times within invertebrates. In terrestrial arthropods traumatic insemination is most prevalent in the true bug infraorder Cimicomorpha, where it has evolved independently at least three times. Traumatic insemination is thought to occur in the Strepsiptera and has recently been recorded in fruit fly and spider lineages. We review the putative selective pressures that may have led to the evolution of traumatic insemination across these lineages, as well as the pressures that continue to drive divergence in male and female reproductive morphology and behavior. Traumatic insemination mechanisms and attributes are compared across independent lineages. PMID:24160423

  3. Feeding and the rhodopsin family g-protein coupled receptors in nematodes and arthropods.

    PubMed

    Cardoso, João C R; Félix, Rute C; Fonseca, Vera G; Power, Deborah M

    2012-01-01

    In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs) play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologs of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans), and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster), suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologs of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR) that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors. PMID:23264768

  4. A Comparison of Conservation Reserve Program Habitat Plantings with Respect to Arthropod Prey for Grassland Birds

    USGS Publications Warehouse

    McIntyre, N.E.; Thompson, Thomas R.

    2003-01-01

    The Conservation Reserve Program (CRP) was designed to reduce soil erosion and curb agricultural overproduction by converting highly erodible agricultural land to various forms of perennial habitat. It has had an incidental benefit of providing habitat for wildlife and has been beneficial in reversing population declines of several grassland bird species. However, the mechanisms behind these reversals remain unknown. One such mechanism may be differences in food availability on CRP vs. non-CRP land or between different types of CRP. The influence of CRP habitat type on the abundance of arthropod prey used by grassland birds has not been previously explored. We compared the abundance and diversity of arthropods among four CRP habitat types in Texas [replicated plots of exotic lovegrass (Eragrostis curvula), Old World bluestem (Bothriochloa ischaemum), mixed native grasses with buffalograss (Buchloe?? dactyloides) and mixed native grasses without buffalograss] and native shortgrass prairie. Attention was focused on adult and juvenile spiders (Order Araneae), beetles (Coleoptera), orthopterans (Orthroptera: grasshoppers and crickets) and lepidopterans (Lepidoptera: butterflies and moths), as these taxa are the primary prey items of grassland birds during the breeding season. Arthropod diversity and abundance were higher on indigenous prairie compared to CRP, reflecting differences in vegetative diversity and structure, but there were no differences in arthropod richness or abundance among CRP types. These results indicate that, although CRP is not equivalent to native prairie in terms of vegetation or arthropod diversity, CRP lands do support arthropod prey for grassland birds. More direct assays of the survivorship and fitness of birds on CRP compared to native shortgrass prairie are clearly warranted.

  5. Feeding and the Rhodopsin Family G-Protein Coupled Receptors in Nematodes and Arthropods

    PubMed Central

    Cardoso, João C.R.; Félix, Rute C.; Fonseca, Vera G.; Power, Deborah M.

    2012-01-01

    In vertebrates, receptors of the rhodopsin G-protein coupled superfamily (GPCRs) play an important role in the regulation of feeding and energy homeostasis and are activated by peptide hormones produced in the brain-gut axis. These peptides regulate appetite and energy expenditure by promoting or inhibiting food intake. Sequence and function homologs of human GPCRs involved in feeding exist in the nematode roundworm, Caenorhabditis elegans (C. elegans), and the arthropod fruit fly, Drosophila melanogaster (D. melanogaster), suggesting that the mechanisms that regulate food intake emerged early and have been conserved during metazoan radiation. Nematodes and arthropods are the most diverse and successful animal phyla on Earth. They can survive in a vast diversity of environments and have acquired distinct life styles and feeding strategies. The aim of the present review is to investigate if this diversity has affected the evolution of invertebrate GPCRs. Homologs of the C. elegans and D. melanogaster rhodopsin receptors were characterized in the genome of other nematodes and arthropods and receptor evolution compared. With the exception of bombesin receptors (BBR) that are absent from nematodes, a similar gene complement was found. In arthropods, rhodopsin GPCR evolution is characterized by species-specific gene duplications and deletions and in nematodes by gene expansions in species with a free-living stage and gene deletions in representatives of obligate parasitic taxa. Based upon variation in GPCR gene number and potentially divergent functions within phyla we hypothesize that life style and feeding diversity practiced by nematodes and arthropods was one factor that contributed to rhodopsin GPCR gene evolution. Understanding how the regulation of food intake has evolved in invertebrates will contribute to the development of novel drugs to control nematodes and arthropods and the pests and diseases that use them as vectors. PMID:23264768

  6. Effects of invasive plants on arthropods.

    PubMed

    Litt, Andrea R; Cord, Erin E; Fulbright, Timothy E; Schuster, Greta L

    2014-12-01

    Non-native plants have invaded nearly all ecosystems and represent a major component of global ecological change. Plant invasions frequently change the composition and structure of vegetation communities, which can alter animal communities and ecosystem processes. We reviewed 87 articles published in the peer-reviewed literature to evaluate responses of arthropod communities and functional groups to non-native invasive plants. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Taxonomic richness decreased in 48% of studies and increased in 13%. Herbivorous arthropods decreased in response to plant invasions in 48% of studies and increased in 17%, likely due to direct effects of decreased plant diversity. Predaceous arthropods decreased in response to invasive plants in 44% of studies, which may reflect indirect effects due to reductions in prey. Twenty-two percent of studies documented increases in predators, which may reflect changes in vegetation structure that improved mobility, survival, or web-building for these species. Detritivores increased in 67% of studies, likely in response to increased litter and decaying vegetation; no studies documented decreased abundance in this functional group. Although many researchers have examined effects of plant invasions on arthropods, sizeable information gaps remain, specifically regarding how invasive plants influence habitat and dietary requirements. Beyond this, the ability to predict changes in arthropod populations and communities associated with plant invasions could be improved by adopting a more functional and mechanistic approach. Understanding responses of arthropods to invasive plants will critically inform conservation of virtually all biodiversity and ecological processes because so many organisms depend on arthropods as prey or for their functional roles, including pollination, seed dispersal, and decomposition. Given their short generation times and ability to respond rapidly to

  7. Numerical experiments with model monophyletic and paraphyletic taxa

    NASA Technical Reports Server (NTRS)

    Sepkoski, J. J. Jr; Kendrick, D. C.; Sepkoski JJ, J. r. (Principal Investigator)

    1993-01-01

    The problem of how accurately paraphyletic taxa versus monophyletic (i.e., holophyletic) groups (clades) capture underlying species patterns of diversity and extinction is explored with Monte Carlo simulations. Phylogenies are modeled as stochastic trees. Paraphyletic taxa are defined in an arbitrary manner by randomly choosing progenitors and clustering all descendants not belonging to other taxa. These taxa are then examined to determine which are clades, and the remaining paraphyletic groups are dissected to discover monophyletic subgroups. Comparisons of diversity patterns and extinction rates between modeled taxa and lineages indicate that paraphyletic groups can adequately capture lineage information under a variety of conditions of diversification and mass extinction. This suggests that these groups constitute more than mere "taxonomic noise" in this context. But, strictly monophyletic groups perform somewhat better, especially with regard to mass extinctions. However, when low levels of paleontologic sampling are simulated, the veracity of clades deteriorates, especially with respect to diversity, and modeled paraphyletic taxa often capture more information about underlying lineages. Thus, for studies of diversity and taxic evolution in the fossil record, traditional paleontologic genera and families need not be rejected in favor of cladistically-defined taxa.

  8. Field Documentation of Unusual Post-Mortem Arthropod Activity on Human Remains.

    PubMed

    Pechal, Jennifer L; Benbow, M Eric; Tomberlin, Jeffery K; Crippen, Tawni L; Tarone, Aaron M; Singh, Baneshwar; Lenhart, Paul A

    2015-01-01

    During a forensic investigation, the presence of physical marks on human remains can influence the interpretation of events related to the death of an individual. Some tissue injury on human remains can be misinterpreted as ante- or peri-mortem wounds by an investigator when in reality the markings resulted from post-mortem arthropod activity. Unusual entomological data were collected during a study examining the decomposition of a set of human remains in San Marcos, Texas. An adult female Pediodectes haldemani (Girard) (Orthoptera: Tettigoniidae) and an Armadillidium cf. vulgare (Isopoda: Armadilidiidae) were documented feeding on the remains. Both arthropods produced physical marks or artifacts on the remains that could be misinterpreted as attack, abuse, neglect, or torture. Additionally, red imported fire ants, Solenopsis invicta Buren (Hymenoptera: Formicidae), were observed constructing structures in the mark produced by the P. haldemani feeding. These observations provide insight into the potential of post-mortem arthropod damage to human remains, which previously had not been described for these taxa, and therefore, physical artifacts on any remains found in similar circumstances may result from arthropod activity and not ante- or peri-mortem wounds. PMID:26336287

  9. Arthropod phylogeny: an overview from the perspectives of morphology, molecular data and the fossil record.

    PubMed

    Edgecombe, Gregory D

    2010-01-01

    Monophyly of Arthropoda is emphatically supported from both morphological and molecular perspectives. Recent work finds Onychophora rather than Tardigrada to be the closest relatives of arthropods. The status of tardigrades as panarthropods (rather than cycloneuralians) is contentious from the perspective of phylogenomic data. A grade of Cambrian taxa in the arthropod stem group includes gilled lobopodians, dinocaridids (e.g., anomalocaridids), fuxianhuiids and canadaspidids that inform on character acquisition between Onychophora and the arthropod crown group. A sister group relationship between Crustacea (itself likely paraphyletic) and Hexapoda is retrieved by diverse kinds of molecular data and is well supported by neuroanatomy. This clade, Tetraconata, can be dated to the early Cambrian by crown group-type mandibles. The rival Atelocerata hypothesis (Myriapoda+Hexapoda) has no molecular support. The basal node in the arthropod crown group is embroiled in a controversy over whether myriapods unite with chelicerates (Paradoxopoda or Myriochelata) or with crustaceans and hexapods (Mandibulata). Both groups find some molecular and morphological support, though Mandibulata is presently the stronger morphological hypothesis. Either hypothesis forces an unsampled ghost lineage for Myriapoda from the Cambrian to the mid Silurian. PMID:19854297

  10. Emerging tools for identification of arthropod vectors.

    PubMed

    Yssouf, Amina; Almeras, Lionel; Raoult, Didier; Parola, Philippe

    2016-04-01

    The rapid and reliable identification of arthropod vector species is an essential component of the fight against vector-borne diseases. However, owing to the lack of entomological expertise required for the morphological identification method, development of alternative and complementary tools is needed. This review describes the main methods used for arthropod identification, focusing on the emergence of protein profiling using MALDI-TOF MS technology. Sample preparation, analysis of reproducibility, database creation and blind tests for controlling accuracy of this tool for arthropod identification are described. The advantages and limitations of the MALDI-TOF MS method are illustrated by emphasizing different hematophagous arthropods, including mosquitoes and ticks, the top two main vectors of infectious diseases. PMID:27070074

  11. ELF communications system ecological monitoring program: Soil arthropods and earthworms

    NASA Astrophysics Data System (ADS)

    Snider, Richard J.; Snider, Renate M.

    1995-04-01

    Based on analysis of years grouped by pre-ELF and operational periods, density fluctuations of arthropods (Collembola and mites) were, in some taxa, significantly different between sites; in others, differences between year groups were significant within either of the study sites. No consistent patterns were seen at the level of species or higher taxa. In some species, effects of the 1988 drought may have carried over into 1989, the first year of antenna operation. Surface-active Collembola, velvet mites and carabid beetles did not alter their activity patterns following antenna activation (e.g., species predominantly spring-active remained spring-active). Although analyses routinely yielded significant differences with respect to total numbers captured in Test and Control, numbers alone were found to be unreliable estimators for disturbance, because a variety of potentially important factors other than EM fields were present. Weekly changes in relative numbers captured, however, showed that increases and decreases in activity were synchronous in the study sites. Carabid beetle activity, which is highly seasonal and governed mainly by reproductive processes, was not affected by EM fields.

  12. Corridor use by diverse taxa.

    SciTech Connect

    Haddad, Nick, M.; Browne, David, R.; Cunningham, Alan; Danielson, Brent, J.; Levey, Douglas, J.; Sargent, Sarah; Spira, Tim

    2003-01-01

    Haddad, N.M., D.R. Browne, A. Cunningham, B.J. Danielson, D.J. Levey, S. Sargent, and T. Spira. 2003. Corridor use by diverse taxa. Ecology, 84(3):609-615. One of the most popular approaches for maintaining populations and conserving biodiversity in fragmented landscapes is to retain or create corridors that connect otherwise isolated habitat patches. Working in large-scale, experimental landscapes in which open-habitat patches and corridors were created by harvesting pine forest, we showed that corridors direct movements of different types of species, including butterflies, small mammals, and bird dispersed plants, causing higher movement between connected than between unconnected patches. Corridors directed the movement of all 10 species studied, with all corridor effect sizes >68%. However, this corridor effect was significant for five species, not significant for one species, and inconclusive for four species because of small sample sizes. Although we found no evidence that corridors increase emigration from a patch, our results show that movements of disparate taxa with broadly different life histories and functional roles are directed by corridors.

  13. Regulation of ecosystem processes by arthropod communities

    SciTech Connect

    Seastedt, T.R.; Crossley, D.A. Jr.

    1983-09-01

    Arthropods or their activities regulate the amounts of forms of mass and nutrients in terrestrial ecosystems. Canopy arthropods have the largest impacts on mobile elements such as potassium, while soil detritivores control mineralization rates of less mobile elements such as nitrogen, phosphorus and calcium. Nominal (base-line) herbivory and detritivory combine to speed nutrient cycling and reduce standing crops of decaying plant materials. 42 references, 1 figure, 3 tables.

  14. Cambrian bivalved arthropod reveals origin of arthrodization.

    PubMed

    Legg, David A; Sutton, Mark D; Edgecombe, Gregory D; Caron, Jean-Bernard

    2012-12-01

    Extant arthropods are diverse and ubiquitous, forming a major constituent of most modern ecosystems. Evidence from early Palaeozoic Konservat Lagerstätten indicates that this has been the case since the Cambrian. Despite this, the details of arthropod origins remain obscure, although most hypotheses regard the first arthropods as benthic predators or scavengers such as the fuxianhuiids or megacheirans ('great-appendage' arthropods). Here, we describe a new arthropod from the Tulip Beds locality of the Burgess Shale Formation (Cambrian, series 3, stage 5) that possesses a weakly sclerotized thorax with filamentous appendages, encased in a bivalved carapace, and a strongly sclerotized, elongate abdomen and telson. A cladistic analysis resolved this taxon as the basal-most member of a paraphyletic grade of nekto-benthic forms with bivalved carapaces. This grade occurs at the base of Arthropoda (panarthropods with arthropodized trunk limbs) and suggests that arthrodization (sclerotization and jointing of the exoskeleton) evolved to facilitate swimming. Predatory and fully benthic habits evolved later in the euarthropod stem-lineage and are plesiomorphically retained in pycnogonids (sea spiders) and euchelicerates (horseshoe crabs and arachnids). PMID:23055069

  15. Cambrian bivalved arthropod reveals origin of arthrodization

    PubMed Central

    Legg, David A.; Sutton, Mark D.; Edgecombe, Gregory D.; Caron, Jean-Bernard

    2012-01-01

    Extant arthropods are diverse and ubiquitous, forming a major constituent of most modern ecosystems. Evidence from early Palaeozoic Konservat Lagerstätten indicates that this has been the case since the Cambrian. Despite this, the details of arthropod origins remain obscure, although most hypotheses regard the first arthropods as benthic predators or scavengers such as the fuxianhuiids or megacheirans (‘great-appendage’ arthropods). Here, we describe a new arthropod from the Tulip Beds locality of the Burgess Shale Formation (Cambrian, series 3, stage 5) that possesses a weakly sclerotized thorax with filamentous appendages, encased in a bivalved carapace, and a strongly sclerotized, elongate abdomen and telson. A cladistic analysis resolved this taxon as the basal-most member of a paraphyletic grade of nekto-benthic forms with bivalved carapaces. This grade occurs at the base of Arthropoda (panarthropods with arthropodized trunk limbs) and suggests that arthrodization (sclerotization and jointing of the exoskeleton) evolved to facilitate swimming. Predatory and fully benthic habits evolved later in the euarthropod stem-lineage and are plesiomorphically retained in pycnogonids (sea spiders) and euchelicerates (horseshoe crabs and arachnids). PMID:23055069

  16. Arthropod-Borne Diseases: The Camper's Uninvited Guests.

    PubMed

    Juckett, Gregory

    2015-08-01

    Arthropod-borne diseases are a major problem whenever outdoor activities bring arthropods and people into contact. The arthropods discussed here include arachnids (ticks) and insects. Most arthropod bites and stings are minor, with the notable exception being bee-sting anaphylaxis. Ticks cause the most disease transmission. Key hard tick vectors include black-legged (Ixodes), dog (Dermacentor), and lone star (Amblyomma) ticks, which transmit Lyme and various rickettsial diseases. Insect repellents, permethrin sprays, and proper tick inspection reduce this risk significantly. Lyme disease and the milder southern-tick-associated rash illness (STARI) are characterized by the erythema migrans rash followed, in the case of Lyme disease, by early, disseminated, and late systemic symptoms. Treatment is with doxycycline or ceftriaxone. Indefinite treatment of "chronic Lyme disease" based on subjective symptoms is not beneficial. Rickettsial diseases include ehrlichiosis, anaplasmosis, and Rocky Mountain spotted fever, which are characterized by fever, headache, and possible rash and should be empirically treated with doxycycline while awaiting laboratory confirmation. Tularemia is a bacterial disease (Francisella) spread by ticks and rabbits and characterized by fever and adenopathy. Treatment is with gentamicin or streptomycin. Babesiosis is a protozoal disease, mimicking malaria, that causes a self-limited flu-like disease in healthy hosts but can be life threatening with immune compromise. Treatment is with atovaquone and azithromycin. Other tick-related conditions include viral diseases (Powassan, Colorado tick fever, heartland virus), tick-borne relapsing fever (Borrelia), and tick paralysis (toxin). Mosquitoes, lice, fleas, and mites are notable for their annoying bites but are increasingly significant disease vectors even in the United States. PMID:26350321

  17. Equine grazing in managed subalpine wetlands: effects on arthropods and plant structure as a function of habitat.

    PubMed

    Holmquist, Jeffrey G; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A

    2013-12-01

    Grazing management necessarily emphasizes the most spatially extensive vegetation assemblages, but landscapes are mosaics, often with more mesic vegetation types embedded within a matrix of drier vegetation. Our primary objective was to contrast effects of equine grazing on both subalpine vegetation structure and associated arthropods in a drier reed grass (Calamagrostis muiriana) dominated habitat versus a wetter, more productive sedge habitat (Carex utriculata). A second objective was to compare reed grass and sedge as habitats for fauna, irrespective of grazing. All work was done in Sequoia National Park (CA, USA), where detailed, long-term records of stock management were available. We sampled paired grazed and control wet meadows that contained both habitats. There were moderate negative effects of grazing on vegetation, and effects were greater in sedge than in reed grass. Conversely, negative grazing effects on arthropods, albeit limited, were greater in the drier reed grass, possibly due to microhabitat differences. The differing effects on plants and animals as a function of habitat emphasize the importance of considering both flora and fauna, as well as multiple habitat types, when making management decisions. Sedge supported twice the overall arthropod abundance of reed grass as well as greater diversity; hemipteran and dipteran taxa were particularly abundant in sedge. Given the greater grazing effects on sedge vegetation, greater habitat provision for terrestrial arthropods, and value as aquatic arthropod habitat, the wetter sedge assemblage is worthy of additional consideration by managers when planning for grazing and other aspects of land usage. PMID:24000111

  18. Equine Grazing in Managed Subalpine Wetlands: Effects on Arthropods and Plant Structure as a Function of Habitat

    NASA Astrophysics Data System (ADS)

    Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A.

    2013-12-01

    Grazing management necessarily emphasizes the most spatially extensive vegetation assemblages, but landscapes are mosaics, often with more mesic vegetation types embedded within a matrix of drier vegetation. Our primary objective was to contrast effects of equine grazing on both subalpine vegetation structure and associated arthropods in a drier reed grass ( Calamagrostis muiriana) dominated habitat versus a wetter, more productive sedge habitat ( Carex utriculata). A second objective was to compare reed grass and sedge as habitats for fauna, irrespective of grazing. All work was done in Sequoia National Park (CA, USA), where detailed, long-term records of stock management were available. We sampled paired grazed and control wet meadows that contained both habitats. There were moderate negative effects of grazing on vegetation, and effects were greater in sedge than in reed grass. Conversely, negative grazing effects on arthropods, albeit limited, were greater in the drier reed grass, possibly due to microhabitat differences. The differing effects on plants and animals as a function of habitat emphasize the importance of considering both flora and fauna, as well as multiple habitat types, when making management decisions. Sedge supported twice the overall arthropod abundance of reed grass as well as greater diversity; hemipteran and dipteran taxa were particularly abundant in sedge. Given the greater grazing effects on sedge vegetation, greater habitat provision for terrestrial arthropods, and value as aquatic arthropod habitat, the wetter sedge assemblage is worthy of additional consideration by managers when planning for grazing and other aspects of land usage.

  19. Arthropods of medicoveterinary importance in zoos.

    PubMed

    Adler, Peter H; Tuten, Holly C; Nelder, Mark P

    2011-01-01

    Zoos present a unique assemblage of arthropods, captive vertebrates, free-roaming wildlife, humans, and plants, each with its own biota of symbiotic organisms. Arthropods of medicoveterinary importance are well represented in zoos, and an ample literature documents their influence in these animal-rich environments. Mosquitoes are of greatest significance because of the animal and human pathogens they transmit, followed by ectoparasites, many of which are exotic and present health risks to captive and native animals. Biting flies, cockroaches, filth flies, and triatomid bugs represent additional concerns. Integrated management programs for arthropods in zoos are commonplace. Zoos can play a role in biosurveillance, serving as an advanced guard for detecting exotic arthropods and vector-borne diseases. We provide the first review of arthropods of medicoveterinary importance in zoos. A case is made for the value of collaborations between entomologists and zoo personnel as a means of enhancing research and public education while safeguarding the health of captive animals and the public. PMID:20731604

  20. Reevaluating the arthropod tree of life.

    PubMed

    Giribet, Gonzalo; Edgecombe, Gregory D

    2012-01-01

    Arthropods are the most diverse group of animals and have been so since the Cambrian radiation. They belong to the protostome clade Ecdysozoa, with Onychophora (velvet worms) as their most likely sister group and tardigrades (water bears) the next closest relative. The arthropod tree of life can be interpreted as a five-taxon network, containing Pycnogonida, Euchelicerata, Myriapoda, Crustacea, and Hexapoda, the last two forming the clade Tetraconata or Pancrustacea. The unrooted relationship of Tetraconata to the three other lineages is well established, but of three possible rooting positions the Mandibulata hypothesis receives the most support. Novel approaches to studying anatomy with noninvasive three-dimensional reconstruction techniques, the application of these techniques to new and old fossils, and the so-called next-generation sequencing techniques are at the forefront of understanding arthropod relationships. Cambrian fossils assigned to the arthropod stem group inform on the origin of arthropod characters from a lobopodian ancestry. Monophyly of Pycnogonida, Euchelicerata, Myriapoda, Tetraconata, and Hexapoda is well supported, but the interrelationships of arachnid orders and the details of crustacean paraphyly with respect to Hexapoda remain the major unsolved phylogenetic problems. PMID:21910637

  1. Habitat and species identity, not diversity, predict the extent of refuse consumption by urban arthropods.

    PubMed

    Youngsteadt, Elsa; Henderson, Ryanna C; Savage, Amy M; Ernst, Andrew F; Dunn, Robert R; Frank, Steven D

    2015-03-01

    Urban green spaces provide ecosystem services to city residents, but their management is hindered by a poor understanding of their ecology. We examined a novel ecosystem service relevant to urban public health and esthetics: the consumption of littered food waste by arthropods. Theory and data from natural systems suggest that the magnitude and resilience of this service should increase with biological diversity. We measured food removal by presenting known quantities of cookies, potato chips, and hot dogs in street medians (24 sites) and parks (21 sites) in New York City, USA. At the same sites, we assessed ground-arthropod diversity and abiotic conditions, including history of flooding during Hurricane Sandy 7 months prior to the study. Arthropod diversity was greater in parks (on average 11 hexapod families and 4.7 ant species per site), than in medians (nine hexapod families and 2.7 ant species per site). However, counter to our diversity-based prediction, arthropods in medians removed 2-3 times more food per day than did those in parks. We detected no effect of flooding (at 19 sites) on this service. Instead, greater food removal was associated with the presence of the introduced pavement ant (Tetramorium sp. E) and with hotter, drier conditions that may have increased arthropod metabolism. When vertebrates also had access to food, more was removed, indicating that arthropods and vertebrates compete for littered food. We estimate that arthropods alone could remove 4-6.5 kg of food per year in a single street median, reducing its availability to less desirable fauna such as rats. Our results suggest that species identity and habitat may be more relevant than diversity for predicting urban ecosystem services. Even small green spaces such as street medians provide ecosystem services that may complement those of larger habitat patches across the urban landscape. PMID:25463151

  2. Microbial ecosystems are dominated by specialist taxa.

    PubMed

    Mariadassou, Mahendra; Pichon, Samuel; Ebert, Dieter

    2015-09-01

    Abundance and specificity are two key characteristics of species distribution and biodiversity. Theories of species assembly aim to reproduce the empirical joint patterns of specificity and abundance, with the goal to explain patterns of biodiversity across habitats. The specialist-generalist paradigm predicts that specialists should have a local advantage over generalists and thus be more abundant. We developed a specificity index to analyse abundance-specificity relationships in microbial ecosystems. By analysing microbiota spanning 23 habitats from three very different data sets covering a wide range of sequencing depths and environmental conditions, we find that habitats are consistently dominated by specialist taxa, resulting in a strong, positive correlation between abundance and specificity. This finding is consistent over several levels of taxonomic aggregation and robust to errors in abundance measures. The relationship explains why shallow sequencing captures similar β-diversity as deep sequencing, and can be sufficient to capture the habitat-specific functions of microbial communities. PMID:26251267

  3. Mineral cycling in soil and litter arthropod food chains. Progress report, November 1, 1981-January 31, 1983

    SciTech Connect

    Crossley, D.A. Jr.

    1982-09-01

    Progress is reported for research projects on nutrient dynamics during terrestrial decomposition, as influenced by soil arthropods. Radioactive tracers are used as analogs of nutrients, to measure material movement along food chains and dynamics of processes during decomposition. Forest floor systems from which arthropods were excluded, or in which microfloral activity was depressed, trapped incoming nutrients from canopy throughfall at different rates. Faunal stimulation of microfloral activities could not be demonstrated, but drought conditions disturbed the experiment. Turnover measurements for radionuclides in collembolans are also reported, and compared with information on mites and other arthropods.

  4. Epidemiology of the arthropod-borne encephalitides*

    PubMed Central

    Miles, J. A. R.

    1960-01-01

    Since the recognition that louping-ill, known for well over 100 years as an epizootic disease of sheep in Scotland, was caused by a virus transmitted by arthropods, many other arthropod-borne viruses capable of causing encephalitis in domestic animals or man have been discovered. The author reviews here the knowledge at present available on these viruses, originally termed ”arthropod-borne encephalitides viruses” but now often referred to as ”arbor viruses”. In this discussion of the host and vector relationships of the two broad groups of arbor viruses — the mosquito-borne and the tick-borne—and of the distribution, epidemiology and control of the various diseases they cause, the author includes an outline of the types of investigation likely to provide the most useful information, stressing in this connexion the value of ecological surveys. PMID:14422369

  5. Sophisticated digestive systems in early arthropods.

    PubMed

    Vannier, Jean; Liu, Jianni; Lerosey-Aubril, Rudy; Vinther, Jakob; Daley, Allison C

    2014-01-01

    Understanding the way in which animals diversified and radiated during their early evolutionary history remains one of the most captivating of scientific challenges. Integral to this is the 'Cambrian explosion', which records the rapid emergence of most animal phyla, and for which the triggering and accelerating factors, whether environmental or biological, are still unclear. Here we describe exceptionally well-preserved complex digestive organs in early arthropods from the early Cambrian of China and Greenland with functional similarities to certain modern crustaceans and trace these structures through the early evolutionary lineage of fossil arthropods. These digestive structures are assumed to have allowed for more efficient digestion and metabolism, promoting carnivory and macrophagy in early arthropods via predation or scavenging. This key innovation may have been of critical importance in the radiation and ecological success of Arthropoda, which has been the most diverse and abundant invertebrate phylum since the Cambrian. PMID:24785191

  6. Collective behavior in an early Cambrian arthropod.

    PubMed

    Hou, Xian-Guang; Siveter, Derek J; Aldridge, Richard J; Siveter, David J

    2008-10-10

    Examples that indicate collective behavior in the fossil record are rare. A group association of specimens that belong to a previously unknown arthropod from the Chengjiang Lagerstätte, China, provides evidence that such behavior was present in the early Cambrian (about 525 million years ago), coincident with the earliest extensive diversification of the Metazoa, the so-called Cambrian explosion event. The chainlike form of these specimens is unique for any arthropod, fossil or living, and most likely represents behavior associated with migration. PMID:18845748

  7. Wolbachia distribution in selected beetle taxa characterized by PCR screens and MLST data.

    PubMed

    Sontowski, Rebekka; Bernhard, Detlef; Bleidorn, Christoph; Schlegel, Martin; Gerth, Michael

    2015-10-01

    Wolbachia (Alphaproteobacteria) is an inherited endosymbiont of arthropods and filarial nematodes and was reported to be widespread across insect taxa. While Wolbachia's effects on host biology are not understood from most of these hosts, known Wolbachia-induced phenotypes cover a spectrum from obligate beneficial mutualism to reproductive manipulations and pathogenicity. Interestingly, data on Wolbachia within the most species-rich order of arthropods, the Coleoptera (beetles), are scarce. Therefore, we screened 128 species from seven beetle families (Buprestidae, Hydraenidae, Dytiscidae, Hydrophilidae, Gyrinidae, Haliplidae, and Noteridae) for the presence of Wolbachia. Our data show that, contrary to previous estimations, Wolbachia frequencies in beetles (31% overall) are comparable to the ones in other insects. In addition, we used Wolbachia MLST data and host phylogeny to explore the evolutionary history of Wolbachia strains from Hydraenidae, an aquatic lineage of beetles. Our data suggest that Wolbachia from Hydraenidae might be largely host genus specific and that Wolbachia strain phylogeny is not independent to that of its hosts. As this contrasts with most terrestrial Wolbachia-arthropod systems, one potential conclusion is that aquatic lifestyle of hosts may result in Wolbachia distribution patterns distinct from those of terrestrial hosts. Our data thus provide both insights into Wolbachia distribution among beetles in general and a first glimpse of Wolbachia distribution patterns among aquatic host lineages. PMID:26664683

  8. Simultaneous assessment of the macrobiome and microbiome in a bulk sample of tropical arthropods through DNA metasystematics

    PubMed Central

    Gibson, Joel; Shokralla, Shadi; Porter, Teresita M.; King, Ian; van Konynenburg, Steven; Janzen, Daniel H.; Hallwachs, Winnie; Hajibabaei, Mehrdad

    2014-01-01

    Conventional assessments of ecosystem sample composition are based on morphology-based or DNA barcode identification of individuals. Both approaches are costly and time-consuming, especially when applied to the large number of specimens and taxa commonly included in ecological investigations. Next-generation sequencing approaches can overcome the bottleneck of individual specimen isolation and identification by simultaneously sequencing specimens of all taxa in a bulk mixture. Here we apply multiple parallel amplification primers, multiple DNA barcode markers, 454-pyrosequencing, and Illumina MiSeq sequencing to the same sample to maximize recovery of the arthropod macrobiome and the bacterial and other microbial microbiome of a bulk arthropod sample. We validate this method with a complex sample containing 1,066 morphologically distinguishable arthropods from a tropical terrestrial ecosystem with high taxonomic diversity. Multiamplicon next-generation DNA barcoding was able to recover sequences corresponding to 91% of the distinguishable individuals in a bulk environmental sample, as well as many species present as undistinguishable tissue. 454-pyrosequencing was able to recover 10 more families of arthropods and 30 more species than did conventional Sanger sequencing of each individual specimen. The use of other loci (16S and 18S ribosomal DNA gene regions) also added the detection of species of microbes associated with these terrestrial arthropods. This method greatly decreases the time and money necessary to perform DNA-based comparisons of biodiversity among ecosystem samples. This methodology opens the door to much cheaper and increased capacity for ecological and evolutionary studies applicable to a wide range of socio-economic issues, as well as a basic understanding of how the world works. PMID:24808136

  9. [Protection of travellers against biting arthropod vectors].

    PubMed

    Carnevale, P

    1998-01-01

    Several diseases are transmitted by hematophageous insect/arthropod and, except for yellow fever and Japanese B encephalitis, there are still no vaccines. Personal protection therefore remains the choice method for disease prevention and can usefully complete chemoprophylaxis if available (such as for malaria). Personal protection can be ensured by three main methods: avoiding risky areas; using repellents on skin and/or garments; using pyrethroids insecticide on garments (permethrin), mosquito nets (several Pyr. available) and any other materials (curtains etc.) including camping tents, plasting "UN sheeting" used in refugees camps etc. Repellent gave some protection for few hours (# 6 hours) and new formulations have been developed to extend their duration. Great care must be taken when using DEET which is not recommended for children and pregnant women. Coils and mats can be used but care must also be taken when using some coils available on local market and which can often be irritating and useless. Mosquito nets impregnated with an insecticide remains the choice method of protection against night-biting insects such as anopheles and is a good way of preventing malaria. Insecticide must be used according to safety measures clearly indicated (or which must be clearly indicated) by companies. All these measures are efficient and must be selected according to local conditions and human behaviour. Travelling is not "risky" but 3 points must be kept in mind: accurate advice must be sought before travelling; this advice must be followed while persuing a "normal life"; a physician must be consulted in case of any trouble during and after the trip. PMID:10078390

  10. Sensitivity and Tolerance of Riparian Arthropod Communities to Altered Water Resources along a Drying River

    PubMed Central

    McCluney, Kevin E.; Sabo, John L.

    2014-01-01

    Background Rivers around the world are drying with increasing frequency, but little is known about effects on terrestrial animal communities. Previous research along the San Pedro River in southeastern AZ, USA, suggests that changes in the availability of water resources associated with river drying lead to changes in predator abundance, community composition, diversity, and abundance of particular taxa of arthropods, but these observations have not yet been tested manipulatively. Methods and Results In this study, we constructed artificial pools in the stream bed adjacent to a drying section of the San Pedro River and maintained them as the river dried. We compared pitfall trapped arthropods near artificial pools to adjacent control sites where surface waters temporarily dried. Assemblage composition changed differentially at multiple taxonomic levels, resulting in different assemblages at pools than at control sites, with multiple taxa and richness of carabid beetle genera increasing at pools but not at controls that dried. On the other hand, predator biomass, particularly wolf spiders, and diversity of orders and families were consistently higher at control sites that dried. These results suggest an important role for colonization dynamics of pools, as well as the ability of certain taxa, particularly burrowing wolf spiders, to withstand periods of temporary drying. Conclusions Overall, we found some agreement between this manipulative study of water resources and a previous analysis of river drying that showed shifts in composition, changes in diversity, and declines in abundance of certain taxa (e.g. carabid beetles). However, colonization dynamics of pools, as well as compensatory strategies of predatory wolf spiders seem to have led to patterns that do not match previous research, with control sites maintaining high diversity, despite drying. Tolerance of river drying by some species may allow persistence of substantial diversity in the face of short

  11. Resistance mechanisms against arthropod herbivores in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton plants from the genus Gossypium are grown on more than 30 million hectares worldwide and are a major source of fiber. The plants possess a wide-range of indirect and direct-defense mechanisms against arthropod pests. Direct defense mechanisms include morphological traits such as trichomes and...

  12. RNAi in agriculturally-important arthropods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our aim in this chapter is to provide an overview of the profound knowledge accumulated in recent years from invertebrate RNAi studies, but with a focus on agriculturally important arthropods. We start with a brief discussion of the RNAi mechanism to introduce readers to key concepts that underlie t...

  13. Dating the arthropod tree based on large-scale transcriptome data.

    PubMed

    Rehm, Peter; Borner, Janus; Meusemann, Karen; von Reumont, Björn M; Simon, Sabrina; Hadrys, Heike; Misof, Bernhard; Burmester, Thorsten

    2011-12-01

    Molecular sequences do not only allow the reconstruction of phylogenetic relationships among species, but also provide information on the approximate divergence times. Whereas the fossil record dates the origin of most multicellular animal phyla during the Cambrian explosion less than 540 million years ago(mya), molecular clock calculations usually suggest much older dates. Here we used a large multiple sequence alignment derived from Expressed Sequence Tags and genomes comprising 129genes (37,476 amino acid positions) and 117 taxa, including 101 arthropods. We obtained consistent divergence time estimates applying relaxed Bayesian clock models with different priors and multiple calibration points. While the influence of substitution rates, missing data, and model priors were negligible, the clock model had significant effect. A log-normal autocorrelated model was selected on basis of cross-validation. We calculated that arthropods emerged ~600 mya. Onychophorans (velvet worms) and euarthropods split ~590 mya, Pancrustacea and Myriochelata ~560 mya, Myriapoda and Chelicerata ~555 mya, and 'Crustacea' and Hexapoda ~510 mya. Endopterygote insects appeared ~390 mya. These dates are considerably younger than most previous molecular clock estimates and in better agreement with the fossil record. Nevertheless, a Precambrian origin of arthropods and other metazoan phyla is still supported. Our results also demonstrate the applicability of large datasets of random nuclear sequences for approximating the timing of multicellular animal evolution. PMID:21945788

  14. Species richness-environment relationships of European arthropods at two spatial grains: habitats and countries.

    PubMed

    Entling, Martin H; Schweiger, Oliver; Bacher, Sven; Espadaler, Xavier; Hickler, Thomas; Kumschick, Sabrina; Woodcock, Ben A; Nentwig, Wolfgang

    2012-01-01

    We study how species richness of arthropods relates to theories concerning net primary productivity, ambient energy, water-energy dynamics and spatial environmental heterogeneity. We use two datasets of arthropod richness with similar spatial extents (Scandinavia to Mediterranean), but contrasting spatial grain (local habitat and country). Samples of ground-dwelling spiders, beetles, bugs and ants were collected from 32 paired habitats at 16 locations across Europe. Species richness of these taxonomic groups was also determined for 25 European countries based on the Fauna Europaea database. We tested effects of net primary productivity (NPP), annual mean temperature (T), annual rainfall (R) and potential evapotranspiration of the coldest month (PET(min)) on species richness and turnover. Spatial environmental heterogeneity within countries was considered by including the ranges of NPP, T, R and PET(min). At the local habitat grain, relationships between species richness and environmental variables differed strongly between taxa and trophic groups. However, species turnover across locations was strongly correlated with differences in T. At the country grain, species richness was significantly correlated with environmental variables from all four theories. In particular, species richness within countries increased strongly with spatial heterogeneity in T. The importance of spatial heterogeneity in T for both species turnover across locations and for species richness within countries suggests that the temperature niche is an important determinant of arthropod diversity. We suggest that, unless climatic heterogeneity is constant across sampling units, coarse-grained studies should always account for environmental heterogeneity as a predictor of arthropod species richness, just as studies with variable area of sampling units routinely consider area. PMID:23029288

  15. Species Richness-Environment Relationships of European Arthropods at Two Spatial Grains: Habitats and Countries

    PubMed Central

    Entling, Martin H.; Schweiger, Oliver; Bacher, Sven; Espadaler, Xavier; Hickler, Thomas; Kumschick, Sabrina; Woodcock, Ben A.; Nentwig, Wolfgang

    2012-01-01

    We study how species richness of arthropods relates to theories concerning net primary productivity, ambient energy, water-energy dynamics and spatial environmental heterogeneity. We use two datasets of arthropod richness with similar spatial extents (Scandinavia to Mediterranean), but contrasting spatial grain (local habitat and country). Samples of ground-dwelling spiders, beetles, bugs and ants were collected from 32 paired habitats at 16 locations across Europe. Species richness of these taxonomic groups was also determined for 25 European countries based on the Fauna Europaea database. We tested effects of net primary productivity (NPP), annual mean temperature (T), annual rainfall (R) and potential evapotranspiration of the coldest month (PETmin) on species richness and turnover. Spatial environmental heterogeneity within countries was considered by including the ranges of NPP, T, R and PETmin. At the local habitat grain, relationships between species richness and environmental variables differed strongly between taxa and trophic groups. However, species turnover across locations was strongly correlated with differences in T. At the country grain, species richness was significantly correlated with environmental variables from all four theories. In particular, species richness within countries increased strongly with spatial heterogeneity in T. The importance of spatial heterogeneity in T for both species turnover across locations and for species richness within countries suggests that the temperature niche is an important determinant of arthropod diversity. We suggest that, unless climatic heterogeneity is constant across sampling units, coarse-grained studies should always account for environmental heterogeneity as a predictor of arthropod species richness, just as studies with variable area of sampling units routinely consider area. PMID:23029288

  16. First record of an arthropod from the Passaic Formation (Late Triassic), near Milford, New Jersey

    NASA Astrophysics Data System (ADS)

    Metz, Robert

    2012-03-01

    Mudstones of the Triassic Passaic Formation, near Milford, New Jersey, have yielded the first evidence of an arthropod impression in that formation. Associated trace fossils include Helminthoidichnites, Lockeia, Scoyenia, Spongeliomorpha, and the reptile footprint Rhynchosauroides, representing the Scoyenia ichnofacies. Associated sedimentary structures include desiccation cracks and raindrop impressions. The Passaic sediments were deposited under shallow water lacustrine shoreline conditions subject to periodic subaerial exposure.

  17. Arthropod Pests and Predators Associated With Bittersweet Nightshade, a Noncrop Host of the Potato Psyllid (Hemiptera: Triozidae).

    PubMed

    Castillo Carrillo, C I; Fu, Z; Jensen, A S; Snyder, W E

    2016-08-01

    Bittersweet nightshade (Solanum dulcamara L.) is a key noncrop host of the potato psyllid (Bactericera cockerelli Šulc), proposed to be a source of the psyllids that colonize potato (Solanum tuberosum L.) fields in the northwestern United States. Here, we describe the broader community of arthropod potato pests, and also predatory arthropods, found in bittersweet nightshade patches. Over 2 yr, we sampled arthropods in patches of this weed spanning the potato-growing region of eastern Washington State. The potato psyllid was the most abundant potato pest that we found, with reproduction of these herbivores recorded throughout much of the growing season where this was measured. Aphid, beetle, and thrips pests of potato also were collected on bittersweet nightshade. In addition to these herbivores, we found a diverse community of >40 predatory arthropod taxa. Spiders, primarily in the Families Dictynidae and Philodromidae, made up 70% of all generalist predator individuals collected. Other generalist predators included multiple species of predatory mites, bugs, and beetles. The coccinellid beetle Stethorus punctillum (Weise) was observed eating psyllid eggs, while the parasitoid wasp Tamarixia triozae (Burks) was observed parasitizing potato psyllid nymphs. Overall, our survey verified the role of bittersweet nightshade as a potato psyllid host, while suggesting that other potato pests also use these plants. At the same time, we found that bittersweet nightshade patches were associated with species-rich communities of natural enemies. Additional work is needed to directly demonstrate movement of pests, and perhaps also predators, from bittersweet nightshade to potato fields. PMID:27357162

  18. Potential and limitations of X-Ray micro-computed tomography in arthropod neuroanatomy: a methodological and comparative survey.

    PubMed

    Sombke, Andy; Lipke, Elisabeth; Michalik, Peter; Uhl, Gabriele; Harzsch, Steffen

    2015-06-01

    Classical histology or immunohistochemistry combined with fluorescence or confocal laser scanning microscopy are common techniques in arthropod neuroanatomy, and these methods often require time-consuming and difficult dissections and sample preparations. Moreover, these methods are prone to artifacts due to compression and distortion of tissues, which often result in information loss and especially affect the spatial relationships of the examined parts of the nervous system in their natural anatomical context. Noninvasive approaches such as X-ray micro-computed tomography (micro-CT) can overcome such limitations and have been shown to be a valuable tool for understanding and visualizing internal anatomy and structural complexity. Nevertheless, knowledge about the potential of this method for analyzing the anatomy and organization of nervous systems, especially of taxa with smaller body size (e.g., many arthropods), is limited. This study set out to analyze the brains of selected arthropods with micro-CT, and to compare these results with available histological and immunohistochemical data. Specifically, we explored the influence of different sample preparation procedures. Our study shows that micro-CT is highly suitable for analyzing arthropod neuroarchitecture in situ and allows specific neuropils to be distinguished within the brain to extract quantitative data such as neuropil volumes. Moreover, data acquisition is considerably faster compared with many classical histological techniques. Thus, we conclude that micro-CT is highly suitable for targeting neuroanatomy, as it reduces the risk of artifacts and is faster than classical techniques. PMID:25728683

  19. Arthropod larvae misidentified as parasitic worm infection.

    PubMed

    Munisamy, Sreetharan; Kilner, Rachael

    2011-01-01

    A healthy, asymptomatic man living in London, presented with seeing 'worms' in his toilet for two successive summer seasons. Repeated microscopic examination and cultures of both his faeces and urine were normal. He was empirically treated with multiple courses of antihelminthics without resolution of this problem. A sample of the worms was obtained, and positively identified as arthropod larvae under microscopic examination. These larvae do not parasitically colonise humans. It was subsequently deduced that a flying arthropod (most likely Culex pipiens mosquito) had laid eggs in standing toilet water, and the hatched larvae had been mistaken for parasitic worms. The patient was declared free of parasites and remains healthy. This case illustrates the dangers of starting empirical treatment without positive confirmation of causative organisms, which can result in unnecessary and potentially harmful treatment. PMID:22675109

  20. Technique for studying arthropod and microbial communities within tree tissues.

    PubMed

    Aflitto, Nicholas C; Hofstetter, Richard W; McGuire, Reagan; Dunn, David D; Potter, Kristen A

    2014-01-01

    Phloem tissues of pine are habitats for many thousands of organisms. Arthropods and microbes use phloem and cambium tissues to seek mates, lay eggs, rear young, feed, or hide from natural enemies or harsh environmental conditions outside of the tree. Organisms that persist within the phloem habitat are difficult to observe given their location under bark. We provide a technique to preserve intact phloem and prepare it for experimentation with invertebrates and microorganisms. The apparatus is called a 'phloem sandwich' and allows for the introduction and observation of arthropods, microbes, and other organisms. This technique has resulted in a better understanding of the feeding behaviors, life-history traits, reproduction, development, and interactions of organisms within tree phloem. The strengths of this technique include the use of inexpensive materials, variability in sandwich size, flexibility to re-open the sandwich or introduce multiple organisms through drilled holes, and the preservation and maintenance of phloem integrity. The phloem sandwich is an excellent educational tool for scientific discovery in both K-12 science courses and university research laboratories. PMID:25489987

  1. Arthropods in amber from the Triassic Period

    PubMed Central

    Schmidt, Alexander R.; Jancke, Saskia; Lindquist, Evert E.; Ragazzi, Eugenio; Roghi, Guido; Nascimbene, Paul C.; Schmidt, Kerstin; Wappler, Torsten; Grimaldi, David A.

    2012-01-01

    The occurrence of arthropods in amber exclusively from the Cretaceous and Cenozoic is widely regarded to be a result of the production and preservation of large amounts of tree resin beginning ca. 130 million years (Ma) ago. Abundant 230 million-year-old amber from the Late Triassic (Carnian) of northeastern Italy has previously yielded myriad microorganisms, but we report here that it also preserves arthropods some 100 Ma older than the earliest prior records in amber. The Triassic specimens are a nematoceran fly (Diptera) and two disparate species of mites, Triasacarus fedelei gen. et sp. nov., and Ampezzoa triassica gen. et sp. nov. These mites are the oldest definitive fossils of a group, the Eriophyoidea, which includes the gall mites and comprises at least 3,500 Recent species, 97% of which feed on angiosperms and represents one of the most specialized lineages of phytophagous arthropods. Antiquity of the gall mites in much their extant form was unexpected, particularly with the Triassic species already having many of their present-day features (such as only two pairs of legs); further, it establishes conifer feeding as an ancestral trait. Feeding by the fossil mites may have contributed to the formation of the amber droplets, but we find that the abundance of amber during the Carnian (ca. 230 Ma) is globally anomalous for the pre-Cretaceous and may, alternatively, be related to paleoclimate. Further recovery of arthropods in Carnian-aged amber is promising and will have profound implications for understanding the evolution of terrestrial members of the most diverse phylum of organisms. PMID:22927387

  2. Arthropods in amber from the Triassic Period.

    PubMed

    Schmidt, Alexander R; Jancke, Saskia; Lindquist, Evert E; Ragazzi, Eugenio; Roghi, Guido; Nascimbene, Paul C; Schmidt, Kerstin; Wappler, Torsten; Grimaldi, David A

    2012-09-11

    The occurrence of arthropods in amber exclusively from the Cretaceous and Cenozoic is widely regarded to be a result of the production and preservation of large amounts of tree resin beginning ca. 130 million years (Ma) ago. Abundant 230 million-year-old amber from the Late Triassic (Carnian) of northeastern Italy has previously yielded myriad microorganisms, but we report here that it also preserves arthropods some 100 Ma older than the earliest prior records in amber. The Triassic specimens are a nematoceran fly (Diptera) and two disparate species of mites, Triasacarus fedelei gen. et sp. nov., and Ampezzoa triassica gen. et sp. nov. These mites are the oldest definitive fossils of a group, the Eriophyoidea, which includes the gall mites and comprises at least 3,500 Recent species, 97% of which feed on angiosperms and represents one of the most specialized lineages of phytophagous arthropods. Antiquity of the gall mites in much their extant form was unexpected, particularly with the Triassic species already having many of their present-day features (such as only two pairs of legs); further, it establishes conifer feeding as an ancestral trait. Feeding by the fossil mites may have contributed to the formation of the amber droplets, but we find that the abundance of amber during the Carnian (ca. 230 Ma) is globally anomalous for the pre-Cretaceous and may, alternatively, be related to paleoclimate. Further recovery of arthropods in Carnian-aged amber is promising and will have profound implications for understanding the evolution of terrestrial members of the most diverse phylum of organisms. PMID:22927387

  3. Arthropod community organization and development in pear

    NASA Astrophysics Data System (ADS)

    Gut, Larry J.; Liss, W. J.; Westigard, P. H.

    1991-01-01

    Arthropod communities in pear are conceptualized as hierarchically organized systems in which several levels of organization or subsystems can be recognized between the population level and the community as a whole. An individual pear tree is taken to be the community habitat with arthropod subcommunities developing on leaf, fruit, and wood subcommunity habitats. Each subcommunity is composed of trophically organized systems of populations. Each system of populations is comprised of a functional group or guild of phytophagous arthropods that use the habitat primarily for feeding but also for overwintering or egg deposition, and associated groups of specialized predators, parasitoids, and hyperparasitoids. Several species move from one subcommunity to another during the course of community development and thus integrate community subsystems. Community development or change in organization through time is conceptualized as being jointly determined by the development of the habitat and the organization of the species pool. The influence of habitat development on community development within a species pool is emphasized in this research. Seasonal habitat development is expressed as change in the kinds and biomasses of developmental states of wood, leaf, and fruit subcommunity habitats. These changes are accompanied by changes in the kinds, biomasses, and distributions of associated community subsystems.

  4. Mormon Cricket Control in Utah's West Desert - Evaluation of Impacts of the Pesticide Diflubenzuron on Nontarget Arthropod Communities

    USGS Publications Warehouse

    Graham, Tim B.; Brasher, Anne M.D.; Close, Rebecca N.

    2008-01-01

    .S. Geological Survey scientists sampled areas in Ibapah and Vernon that had been treated with diflubenzuron in 2004, along with adjacent untreated areas. Pitfall traps at four treated and four untreated sites were used to collect ground-dwelling terrestrial arthropods. Semiquantitative sweep surveys of aquatic habitats were made before treatment, 2 weeks after treatment, and 4 months after treatment (after leaf fall) at Grouse Creek. One-year post-treatment samples were collected by using the same methods for terrestrial and aquatic arthropods at Ibapah and Vernon in July 2005 (treatments applied in June 2004). More than 124,000 terrestrial arthropods were collected from the three study areas, and more than 200,000 aquatic invertebrates were collected in the aquatic samples. Direct effects of diflubenzuron on aquatic and terrestrial arthropod communities were not apparent in our data from Grouse Creek. The treatment was designed to avoid spraying pesticide on water bodies, and no measurable effects on aquatic communities from either springs or streams were observed, with the exception of the reduction of taxa richness at Vernon (a result confounded by elevational differences in the treatment and nontreatment zones). Some trends indicate diflubenzuron may affect some terrestrial taxa. Ant communities showed some differences, with possible lag effects at Ibapah and Vernon. Forelius was more abundant, while Tapinoma and, perhaps, Formica declined in treated zones in these two study areas. Solenopsis also was more numerous at treated Ibapah sites but varied without pattern at Vernon. Scorpions were abundant at Grouse Creek and Ibapah but rare at Vernon. Numbers did not change during several weeks at Grouse Creek, but at Ibapah, numbers at treated sites were much lower than at untreated sites. The Lygaeidae (in the order Hemiptera) were more abundant in the untreated zones at Ibapah and Vernon, although significantly so only at Ibapah. Lygaeidae were absent from th

  5. Bacterial symbiosis in arthropods and the control of disease transmission.

    PubMed Central

    Beard, C. B.; Durvasula, R. V.; Richards, F. F.

    1998-01-01

    Bacterial symbionts may be used as vehicles for expressing foreign genes in arthropods. Expression of selected genes can render an arthropod incapable of transmitting a second microorganism that is pathogenic for humans and is an alternative approach to the control of arthropod-borne diseases. We discuss the rationale for this alternative approach, its potential applications and limitations, and the regulatory concerns that may arise from its use in interrupting disease transmission in humans and animals. PMID:9866734

  6. Character phylogenies in Candacia and Paracandacia (Copepoda, Calanoida) and the inevitably paraphyletic nature of many nominal taxa above subspecies level

    NASA Astrophysics Data System (ADS)

    von Vaupel Klein, J. C.; Gassmann, D.

    1998-06-01

    Examination of the phylogenetic structure of the family Candaciidae shows the genus Paracandacia to comprise a strongly modified branch emerging from the clade commonly denoted as Candacia. This has been confirmed by studying selected character phylogenies. It is argued that the resulting paraphyletic nature of Candacia auct., though in a cladistic context undesirable on theoretical grounds, has to be accepted as inevitable. Recent studies on molluscs and arthropods, viz., have demonstrated that the continuous origin of paraphyletic taxa from previously monophyletic ones is nothing but a naturally occurring process, intrinsically embodied in the course of evolution.

  7. The midgut epithelium of aquatic arthropods: a critical target organ in environmental toxicology.

    PubMed Central

    Beaty, Barry J; Mackie, Ryan S; Mattingly, Kimberly S; Carlson, Jonathan O; Rayms-Keller, Alfredo

    2002-01-01

    The midgut epithelium of aquatic arthropods is emerging as an important and toxicologically relevant organ system for monitoring environmental pollution. The peritrophic matrix of aquatic arthropods, which is secreted by the midgut epithelium cells, is perturbed by copper or cadmium. Molecular biological studies have identified and characterized two midgut genes induced by heavy metals in the midgut epithelium. Many other metal-responsive genes (MRGs) await characterization. One of the MRGs codes for an intestinal mucin, which is critical for protecting the midgut from toxins and pathogens. Another codes for a tubulin gene, which is critical for structure and function of the midgut epithelial cells. Perturbation of expression of either gene could condition aquatic arthropod survivorship. Induction of these MRGs is a more sensitive and rapid indicator of heavy-metal pollution than biological assays. Characterization of genes induced by pollutants could provide mechanistic understanding of fundamental cellular responses to pollutants and insight into determinants of aquatic arthropod population genetic structure and survivorship in nature. PMID:12634118

  8. The Hunsrück biota: A unique window into the ecology of Lower Devonian arthropods.

    PubMed

    Rust, Jes; Bergmann, Alexandra; Bartels, Christoph; Schoenemann, Brigitte; Sedlmeier, Stephanie; Kühl, Gabriele

    2016-03-01

    The approximately 400-million-year old Hunsrück biota provides a unique window into Devonian marine life. Fossil evidence suggests that this biota was dominated by echinoderms and various classes of arthropods, including Trilobita, stem lineage representatives of Euarthropoda, Chelicerata and Eucrustacea, as well as several crown group Chelicerata and Eucrustacea. The Hunsrück biota's exceptional preservation allows detailed reconstructions and description of key-aspects of its fauna's functional morphologies thereby revealing modes of locomotion, sensory perception, and feeding strategies. Morphological and stratigraphic data are used for a critical interpretation of the likely habitats, mode of life and nutritional characteristics of this diverse fauna. Potential predators include pycnogonids and other chelicerates, as well as the now extinct stem arthropods Schinderhannes bartelsi, Cambronatus brasseli and Wingertshellicus backesi. Mainly the deposit feeding Trilobita, Marrellomorpha and Megacheira, such as Bundenbachiellus giganteus, represents scavengers. Possibly, opportunistic scavenging was also performed by the afore-mentioned predators. Most of the studied arthropods appear to have been adapted to living in relatively well-illuminated conditions within the photic zone. Fossil evidence for associations amongst arthropods and other classes of metazoans is reported. These associations provide evidence of likely community structures. PMID:26826500

  9. Taxon-specific PCR for DNA barcoding arthropod prey in bat faeces.

    PubMed

    Zeale, Matt R K; Butlin, Roger K; Barker, Gary L A; Lees, David C; Jones, Gareth

    2011-03-01

    The application of DNA barcoding to dietary studies allows prey taxa to be identified in the absence of morphological evidence and permits a greater resolution of prey identity than is possible through direct examination of faecal material. For insectivorous bats, which typically eat a great diversity of prey and which chew and digest their prey thoroughly, DNA-based approaches to diet analysis may provide the only means of assessing the range and diversity of prey within faeces. Here, we investigated the effectiveness of DNA barcoding in determining the diets of bat species that specialize in eating different taxa of arthropod prey. We designed and tested a novel taxon-specific primer set and examined the performance of short barcode sequences in resolving prey species. We recovered prey DNA from all faecal samples and subsequent cloning and sequencing of PCR products, followed by a comparison of sequences to a reference database, provided species-level identifications for 149/207 (72%) clones. We detected a phylogenetically broad range of prey while completely avoiding detection of nontarget groups. In total, 37 unique prey taxa were identified from 15 faecal samples. A comparison of DNA data with parallel morphological analyses revealed a close correlation between the two methods. However, the sensitivity and taxonomic resolution of the DNA method were far superior. The methodology developed here provides new opportunities for the study of bat diets and will be of great benefit to the conservation of these ecologically important predators. PMID:21429129

  10. How Did Arthropod Sesquiterpenoids and Ecdysteroids Arise? Comparison of Hormonal Pathway Genes in Noninsect Arthropod Genomes

    PubMed Central

    Qu, Zhe; Kenny, Nathan James; Lam, Hon Ming; Chan, Ting Fung; Chu, Ka Hou; Bendena, William G.; Tobe, Stephen S.; Hui, Jerome Ho Lam

    2015-01-01

    The phylum Arthropoda contains the largest number of described living animal species, with insects and crustaceans dominating the terrestrial and aquatic environments, respectively. Their successful radiations have long been linked to their rigid exoskeleton in conjunction with their specialized endocrine systems. In order to understand how hormones can contribute to the evolution of these animals, here, we have categorized the sesquiterpenoid and ecdysteroid pathway genes in the noninsect arthropod genomes, which are known to play important roles in the regulation of molting and metamorphosis in insects. In our analyses, the majority of gene homologs involved in the biosynthetic, degradative, and signaling pathways of sesquiterpenoids and ecdysteroids can be identified, implying these two hormonal systems were present in the last common ancestor of arthropods. Moreover, we found that the “Broad-Complex” was specifically gained in the Pancrustacea, and the innovation of juvenile hormone (JH) in the insect linage correlates with the gain of the JH epoxidase (CYP15A1/C1) and the key residue changes in the binding domain of JH receptor (“Methoprene-tolerant”). Furthermore, the gain of “Phantom” differentiates chelicerates from the other arthropods in using ponasterone A rather than 20-hydroxyecdysone as molting hormone. This study establishes a comprehensive framework for interpreting the evolution of these vital hormonal pathways in these most successful animals, the arthropods, for the first time. PMID:26112967

  11. How Did Arthropod Sesquiterpenoids and Ecdysteroids Arise? Comparison of Hormonal Pathway Genes in Noninsect Arthropod Genomes.

    PubMed

    Qu, Zhe; Kenny, Nathan James; Lam, Hon Ming; Chan, Ting Fung; Chu, Ka Hou; Bendena, William G; Tobe, Stephen S; Hui, Jerome Ho Lam

    2015-07-01

    The phylum Arthropoda contains the largest number of described living animal species, with insects and crustaceans dominating the terrestrial and aquatic environments, respectively. Their successful radiations have long been linked to their rigid exoskeleton in conjunction with their specialized endocrine systems. In order to understand how hormones can contribute to the evolution of these animals, here, we have categorized the sesquiterpenoid and ecdysteroid pathway genes in the noninsect arthropod genomes, which are known to play important roles in the regulation of molting and metamorphosis in insects. In our analyses, the majority of gene homologs involved in the biosynthetic, degradative, and signaling pathways of sesquiterpenoids and ecdysteroids can be identified, implying these two hormonal systems were present in the last common ancestor of arthropods. Moreover, we found that the "Broad-Complex" was specifically gained in the Pancrustacea, and the innovation of juvenile hormone (JH) in the insect linage correlates with the gain of the JH epoxidase (CYP15A1/C1) and the key residue changes in the binding domain of JH receptor ("Methoprene-tolerant"). Furthermore, the gain of "Phantom" differentiates chelicerates from the other arthropods in using ponasterone A rather than 20-hydroxyecdysone as molting hormone. This study establishes a comprehensive framework for interpreting the evolution of these vital hormonal pathways in these most successful animals, the arthropods, for the first time. PMID:26112967

  12. Habitat connectivity shapes urban arthropod communities: the key role of green roofs.

    PubMed

    Braaker, S; Ghazoul, J; Obrist, M K; Moretti, M

    2014-04-01

    The installation of green roofs, defined here as rooftops with a shallow soil cover and extensive vegetation, has been proposed as a possible measure to mitigate the loss of green space caused by the steady growth of cities. However, the effectiveness of green roofs in supporting arthropod communities, and the extent to which they facilitate connectivity of these communities within the urban environment is currently largely unknown. We investigated the variation of species community composition (beta diversity) of four arthropod groups with contrasting mobility (Carabidae, Araneae, Curculionidae, and Apidae) on 40 green roofs and 40 extensively managed green sites on the ground in the city of Zurich, Switzerland. With redundancy analysis and variation partitioning, we (1) disentangled the relative importance of local environmental conditions, the surrounding land cover composition, and habitat connectivity on species community composition, (2) searched for specific spatial scales of habitat connectivity for the different arthropod groups, and (3) discussed the ecological and functional value of green roofs in cities. Our study revealed that on green roofs community composition of high-mobility arthropod groups (bees and weevils) were mainly shaped by habitat connectivity, while low-mobility arthropod groups (carabids and spiders) were more influenced by local environmental conditions. A similar but less pronounced pattern was found for ground communities. The high importance of habitat connectivity in shaping high-mobility species community composition indicates that these green roof communities are substantially connected by the frequent exchange of individuals among surrounding green roofs. On the other hand, low-mobility species communities on green roofs are more likely connected to ground sites than to other green roofs. The integration of green roofs in urban spatial planning strategies has great potential to enable higher connectivity among green spaces, so

  13. Biobased lactams as novel arthropod repellents.

    PubMed

    Chauhan, Kamlesh R; Khanna, Hemant; Bathini, Nagendra Babu; Le, Thanh C; Grieco, John

    2014-12-01

    Enanatiomerically pure 4aS,7S,7aR and 4aS,7S,7aS-nepetalactams and their analogs have been prepared in just two steps from 4aS,7S,7aR and 4aS,7S,7aS-nepetalactones, major components of catnip oil. Lactams or cyclic amides from iridoid monoterpenes are generated and being evaluated as a new class of compounds as arthropod deterrents against disease vectors. PMID:25632454

  14. Seasonal abundance of soil arthropods in relation to meteorological and edaphic factors in the agroecosystems of Faisalabad, Punjab, Pakistan.

    PubMed

    Shakir, Muhammad Mussadiq; Ahmed, Sohail

    2015-05-01

    arthropods were the major contributors of variation in overall abundance in extreme temperature months while microarthropods in low-temperature months. CCA analysis revealed the occurrence of different arthropod groups in correspondence with different abiotic variables. Results are discussed in view of position of these arthropods as useful indicators under changing environmental conditions impacting agroecosystems in the study area. PMID:25085701

  15. Seasonal abundance of soil arthropods in relation to meteorological and edaphic factors in the agroecosystems of Faisalabad, Punjab, Pakistan

    NASA Astrophysics Data System (ADS)

    Shakir, Muhammad Mussadiq; Ahmed, Sohail

    2015-05-01

    arthropods were the major contributors of variation in overall abundance in extreme temperature months while microarthropods in low-temperature months. CCA analysis revealed the occurrence of different arthropod groups in correspondence with different abiotic variables. Results are discussed in view of position of these arthropods as useful indicators under changing environmental conditions impacting agroecosystems in the study area.

  16. New taxa of Euglenophyta from China

    NASA Astrophysics Data System (ADS)

    Shi, Zhi-Xin

    1995-12-01

    Eight new taxa of Euglenophyta are described in this paper. They were collected from several provinces in China and respectively named Euglena allorgei var. exsulcata, E. pisciformis var. globosa, E. tortilis. Lepocinclis glabra var. papillata, Phacus pisiformis, Ph. strombuliformis, Ph. trimarginatus var. truncatus and Astasia angusta.

  17. Transportable data from non-target arthropod field studies for the environmental risk assessment of genetically modified maize expressing an insecticidal double-stranded RNA.

    PubMed

    Ahmad, Aqeel; Negri, Ignacio; Oliveira, Wladecir; Brown, Christopher; Asiimwe, Peter; Sammons, Bernard; Horak, Michael; Jiang, Changjian; Carson, David

    2016-02-01

    As part of an environmental risk assessment, the potential impact of genetically modified (GM) maize MON 87411 on non-target arthropods (NTAs) was evaluated in the field. MON 87411 confers resistance to corn rootworm (CRW; Diabrotica spp.) by expressing an insecticidal double-stranded RNA (dsRNA) transcript and the Cry3Bb1 protein and tolerance to the herbicide glyphosate by producing the CP4 EPSPS protein. Field trials were conducted at 14 sites providing high geographic and environmental diversity within maize production areas from three geographic regions including the U.S., Argentina, and Brazil. MON 87411, the conventional control, and four commercial conventional reference hybrids were evaluated for NTA abundance and damage. Twenty arthropod taxa met minimum abundance criteria for valid statistical analysis. Nine of these taxa occurred in at least two of the three regions and in at least four sites across regions. These nine taxa included: aphid, predatory earwig, lacewing, ladybird beetle, leafhopper, minute pirate bug, parasitic wasp, sap beetle, and spider. In addition to wide regional distribution, these taxa encompass the ecological functions of herbivores, predators and parasitoids in maize agro-ecosystems. Thus, the nine arthropods may serve as representative taxa of maize agro-ecosystems, and thereby support that analysis of relevant data generated in one region can be transportable for the risk assessment of the same or similar GM crop products in another region. Across the 20 taxa analyzed, no statistically significant differences in abundance were detected between MON 87411 and the conventional control for 123 of the 128 individual-site comparisons (96.1%). For the nine widely distributed taxa, no statistically significant differences in abundance were detected between MON 87411 and the conventional control. Furthermore, no statistically significant differences were detected between MON 87411 and the conventional control for 53 out of 56 individual

  18. Leaving A Mark: A Comparison Arthropod Protein Marking Protocols

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge of arthropod pest and natural enemy disperal patterns is needed for effective and environmentally benign pest control. The most common tactics used to monitor arthropod dispersal patterns include mark-release-recapture (MRR) and mark-capture methodologies. Both methods require the applica...

  19. A molecular palaeobiological exploration of arthropod terrestrialization.

    PubMed

    Lozano-Fernandez, Jesus; Carton, Robert; Tanner, Alastair R; Puttick, Mark N; Blaxter, Mark; Vinther, Jakob; Olesen, Jørgen; Giribet, Gonzalo; Edgecombe, Gregory D; Pisani, Davide

    2016-07-19

    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems.This article is part of the themed issue 'Dating species divergences using rocks and clocks'. PMID:27325830

  20. A Silurian short-great-appendage arthropod

    PubMed Central

    Siveter, Derek J.; Briggs, Derek E. G.; Siveter, David J.; Sutton, Mark D.; Legg, David; Joomun, Sarah

    2014-01-01

    A new arthropod, Enalikter aphson gen. et sp. nov., is described from the Silurian (Wenlock Series) Herefordshire Lagerstätte of the UK. It belongs to the Megacheira (=short-great-appendage group), which is recognized here, for the first time, in strata younger than mid-Cambrian age. Discovery of this new Silurian taxon allows us to identify a Devonian megacheiran representative, Bundenbachiellus giganteus from the Hunsrück Slate of Germany. The phylogenetic position of megacheirans is controversial: they have been interpreted as stem chelicerates, or stem euarthropods, but when Enalikter and Bundenbachiellus are added to the most comprehensive morphological database available, a stem euarthropod position is supported. Enalikter represents the only fully three-dimensionally preserved stem-group euarthropod, it falls in the sister clade to the crown-group euarthropods, and it provides new insights surrounding the origin and early evolution of the euarthropods. Recognition of Enalikter and Bundenbachiellus as megacheirans indicates that this major arthropod group survived for nearly 100 Myr beyond the mid-Cambrian. PMID:24452026

  1. A molecular palaeobiological exploration of arthropod terrestrialization

    PubMed Central

    Carton, Robert; Edgecombe, Gregory D.

    2016-01-01

    Understanding animal terrestrialization, the process through which animals colonized the land, is crucial to clarify extant biodiversity and biological adaptation. Arthropoda (insects, spiders, centipedes and their allies) represent the largest majority of terrestrial biodiversity. Here we implemented a molecular palaeobiological approach, merging molecular and fossil evidence, to elucidate the deepest history of the terrestrial arthropods. We focused on the three independent, Palaeozoic arthropod terrestrialization events (those of Myriapoda, Hexapoda and Arachnida) and showed that a marine route to the colonization of land is the most likely scenario. Molecular clock analyses confirmed an origin for the three terrestrial lineages bracketed between the Cambrian and the Silurian. While molecular divergence times for Arachnida are consistent with the fossil record, Myriapoda are inferred to have colonized land earlier, substantially predating trace or body fossil evidence. An estimated origin of myriapods by the Early Cambrian precedes the appearance of embryophytes and perhaps even terrestrial fungi, raising the possibility that terrestrialization had independent origins in crown-group myriapod lineages, consistent with morphological arguments for convergence in tracheal systems. This article is part of the themed issue ‘Dating species divergences using rocks and clocks’. PMID:27325830

  2. New approaches narrow global species estimates for beetles, insects, and terrestrial arthropods

    PubMed Central

    Stork, Nigel E.; McBroom, James; Gely, Claire; Hamilton, Andrew J.

    2015-01-01

    It has been suggested that we do not know within an order of magnitude the number of all species on Earth [May RM (1988) Science 241(4872):1441–1449]. Roughly 1.5 million valid species of all organisms have been named and described [Costello MJ, Wilson S, Houlding B (2012) Syst Biol 61(5):871–883]. Given Kingdom Animalia numerically dominates this list and virtually all terrestrial vertebrates have been described, the question of how many terrestrial species exist is all but reduced to one of how many arthropod species there are. With beetles alone accounting for about 40% of all described arthropod species, the truly pertinent question is how many beetle species exist. Here we present four new and independent estimates of beetle species richness, which produce a mean estimate of 1.5 million beetle species. We argue that the surprisingly narrow range (0.9–2.1 million) of these four autonomous estimates—derived from host-specificity relationships, ratios with other taxa, plant:beetle ratios, and a completely novel body-size approach—represents a major advance in honing in on the richness of this most significant taxon, and is thus of considerable importance to the debate on how many species exist. Using analogous approaches, we also produce independent estimates for all insects, mean: 5.5 million species (range 2.6–7.8 million), and for terrestrial arthropods, mean: 6.8 million species (range 5.9–7.8 million), which suggest that estimates for the world’s insects and their relatives are narrowing considerably. PMID:26034274

  3. New approaches narrow global species estimates for beetles, insects, and terrestrial arthropods.

    PubMed

    Stork, Nigel E; McBroom, James; Gely, Claire; Hamilton, Andrew J

    2015-06-16

    It has been suggested that we do not know within an order of magnitude the number of all species on Earth [May RM (1988) Science 241(4872):1441-1449]. Roughly 1.5 million valid species of all organisms have been named and described [Costello MJ, Wilson S, Houlding B (2012) Syst Biol 61(5):871-883]. Given Kingdom Animalia numerically dominates this list and virtually all terrestrial vertebrates have been described, the question of how many terrestrial species exist is all but reduced to one of how many arthropod species there are. With beetles alone accounting for about 40% of all described arthropod species, the truly pertinent question is how many beetle species exist. Here we present four new and independent estimates of beetle species richness, which produce a mean estimate of 1.5 million beetle species. We argue that the surprisingly narrow range (0.9-2.1 million) of these four autonomous estimates--derived from host-specificity relationships, ratios with other taxa, plant:beetle ratios, and a completely novel body-size approach--represents a major advance in honing in on the richness of this most significant taxon, and is thus of considerable importance to the debate on how many species exist. Using analogous approaches, we also produce independent estimates for all insects, mean: 5.5 million species (range 2.6-7.8 million), and for terrestrial arthropods, mean: 6.8 million species (range 5.9-7.8 million), which suggest that estimates for the world's insects and their relatives are narrowing considerably. PMID:26034274

  4. Biodiversity and resilience of arthropod communities after fire disturbance in temperate forests.

    PubMed

    Moretti, Marco; Duelli, Peter; Obrist, Martin K

    2006-08-01

    Changes in ecosystem functions following disturbances are of central concern in ecology and a challenge for ecologists is to understand the factors that affect the resilience of community structures and ecosystem functions. In many forest ecosystems, one such important natural disturbance is fire. The aim of this study was to understand the variation of resilience in six functional groups of invertebrates in response to different fire frequencies in southern Switzerland. We measured resilience by analysing arthropod species composition, abundance and diversity in plots where the elapsed time after single or repeated fires, as determined by dendrochronology, varied. We compared data from these plots with data from plots that had not burned recently and defined high resilience as the rapid recovery of the species composition to that prior to fire. Pooling all functional groups showed that they were more resilient to single fires than to repeated events, recovering 6-14 years after a single fire, but only 17-24 years after the last of several fires. Flying zoophagous and phytophagous arthropods were the most resilient groups. Pollinophagous and epigaeic zoophagous species showed intermediate resilience, while ground-litter saprophagous and saproxylophagous arthropods clearly displayed the lowest resilience to fire. Their species composition 17-24 years post-burn still differed markedly from that of the unburned control plots. Depending on the fire history of a forest plot, we found significant differences in the dominance hierarchy among invertebrate species. Any attempt to imitate natural disturbances, such as fire, through forest management must take into account the recovery times of biodiversity, including functional group composition, to ensure the conservation of multiple taxa and ecosystem functions in a sustainable manner. PMID:16804704

  5. The ecology of sex explains patterns of helping in arthropod societies.

    PubMed

    Davies, Nicholas G; Ross, Laura; Gardner, Andy

    2016-08-01

    Across arthropod societies, sib-rearing (e.g. nursing or nest defence) may be provided by females, by males or by both sexes. According to Hamilton's 'haplodiploidy hypothesis', this diversity reflects the relatedness consequences of diploid vs. haplodiploid inheritance. However, an alternative 'preadaptation hypothesis' instead emphasises an interplay of ecology and the co-option of ancestral, sexually dimorphic traits for sib-rearing. The preadaptation hypothesis has recently received empirical support, but remains to be formalised. Here, we mathematically model the coevolution of sex-specific helping and sex allocation, contrasting these hypotheses. We find that ploidy per se has little effect. Rather, the ecology of sex shapes patterns of helping: sex-specific preadaptation strongly influences who helps; a freely adjustable sex ratio magnifies sex biases and promotes helping; and sib-mating, promiscuity, and reproductive autonomy also modulate the sex and abundance of helpers. An empirical survey reveals that patterns of sex-specific helping in arthropod taxa are consistent with the preadaptation hypothesis. PMID:27250600

  6. Arthropod prey of Wilson's Warblers in the understory of Douglas-fir forests

    USGS Publications Warehouse

    Hagar, J.C.; Dugger, K.M.; Starkey, E.E.

    2007-01-01

    Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wilson's Warblers (Wilsonia pusilla) that foraged in the understory of Douglas-fir (Pseudotsuga menziesii) forests in western Oregon during the breeding season. We sampled arthropods at the same sites where diet data were collected, and compared abundance and biomass of prey among seven common shrub species. Wilson's Warblers ate more caterpillars (Lepidoptera larvae), flies (Diptera), beetles (Coleoptera), and Homoptera than expected based on availability. Deciduous shrubs supported higher abundances of arthropod taxa and size classes used as prey by Wilson's Warblers than did evergreen shrubs. The development and maintenance of deciduous understory vegetation in conifer forests of the Pacific Northwest may be fundamental for conservation of food webs that support breeding Wilson's Warblers and other shrub-associated, insectivorous songbirds.

  7. Mitochondrial gene arrangement of the horseshoe crab Limulus polyphemus L.: conservation of major features among arthropod classes

    NASA Technical Reports Server (NTRS)

    Staton, J. L.; Daehler, L. L.; Brown, W. M.; Jacobs, D. K. (Principal Investigator)

    1997-01-01

    Numerous complete mitochondrial DNA sequences have been determined for species within two arthropod groups, insects and crustaceans, but there are none for a third, the chelicerates. Most mitochondrial gene arrangements reported for crustaceans and insect species are identical or nearly identical to that of Drosophila yakuba. Sequences across 36 of the gene boundaries in the mitochondrial DNA (mtDNA) of a representative chelicerate. Limulus polyphemus L., also reveal an arrangement like that of Drosophila yakuba. Only the position of the tRNA(LEU)(UUR) gene differs; in Limulus it is between the genes for tRNA(LEU)(CUN) and ND1. This positioning is also found in onychophorans, mollusks, and annelids, but not in insects and crustaceans, and indicates that tRNA(LEU)(CUN)-tRNA(LEU)(UUR)-ND1 was the ancestral gene arrangement for these groups, as suggested earlier. There are no differences in the relative arrangements of protein-coding and ribosomal RNA genes between Limulus and Drosophila, and none have been observed within arthropods. The high degree of similarity of mitochondrial gene arrangements within arthropods is striking, since some taxa last shared a common ancestor before the Cambrian, and contrasts with the extensive mtDNA rearrangements occasionally observed within some other metazoan phyla (e.g., mollusks and nematodes).

  8. Arthropod-borne encephalitides in the Americas*

    PubMed Central

    Monath, T. P.

    1979-01-01

    The arthropod-borne encephalitides are an important cause of equine and human morbidity in the Americas. Between 1975 and 1978, 6970 human cases of arboviral encephalitis were reported in the United States of America; however, this represents only a fraction of the true incidence. St Louis encephalitis (4824 cases), California encephalitis (1035 cases), and western equine encephalitis (WEE, 947 cases) accounted for 98.5% of all reported infections. Approximately 1000-4000 cases of equine encephalitis occur annually in the United States, the majority due to WEE. In tropical America, important outbreaks of Venezuelan, eastern, and western equine encephalitis, and of Rocio encephalitis have occurred. In this article, epidemiological aspects of arboviral encephalitis outbreaks occurring within the past 5 years are reviewed. In addition, summaries of current research activities on the ecology and epidemiology of St Louis, western equine, Venezuelan equine, Rocio, and California encephalitis viruses are presented, and the problem of control of these infections is discussed. PMID:93518

  9. An effective method for terrestrial arthropod euthanasia.

    PubMed

    Bennie, Neil A C; Loaring, Christopher D; Bennie, Mikaella M G; Trim, Steven A

    2012-12-15

    As scientific understanding of invertebrate life increases, so does the concern for how to end that life in an effective way that minimises (potential) suffering and is also safe for those carrying out the procedure. There is increasing debate on the most appropriate euthanasia methods for invertebrates as their use in experimental research and zoological institutions grows. Their popularity as pet species has also led to an increase in the need for greater veterinary understanding. Through the use of a local injection of potassium chloride (KCl) initially developed for use in American lobsters, this paper describes a safe and effective method for euthanasia in terrestrial invertebrates. Initial work focused on empirically determining the dose for cockroaches, which was then extrapolated to other arthropod species. For this method of euthanasia, we propose the term 'targeted hyperkalosis' to describe death through terminal depolarisation of the thoracic ganglia as a result of high potassium concentration. PMID:22996446

  10. Ecdysis triggering hormone signaling in arthropods.

    PubMed

    Roller, Ladislav; Zitnanová, Inka; Dai, Li; Simo, Ladislav; Park, Yoonseong; Satake, Honoo; Tanaka, Yoshiaki; Adams, Michael E; Zitnan, Dusan

    2010-03-01

    Ecdysis triggering hormones (ETHs) from endocrine Inka cells initiate the ecdysis sequence through action on central neurons expressing ETH receptors (ETHR) in model moth and dipteran species. We used various biochemical, molecular and BLAST search techniques to detect these signaling molecules in representatives of diverse arthropods. Using peptide isolation from tracheal extracts, cDNA cloning or homology searches, we identified ETHs in a variety of hemimetabolous and holometabolous insects. Most insects produce two related ETHs, but only a single active peptide was isolated from the cricket and one peptide is encoded by the eth gene of the honeybee, parasitic wasp and aphid. Immunohistochemical staining with antiserum to Manduca PETH revealed Inka cells on tracheal surface of diverse insects. In spite of conserved ETH sequences, comparison of natural and the ETH-induced ecdysis sequence in the honeybee and beetle revealed considerable species-specific differences in pre-ecdysis and ecdysis behaviors. DNA sequences coding for putative ETHR were deduced from available genomes of several hemimetabolous and holometabolous insects. In all insects examined, the ethr gene encodes two subtypes of the receptor (ETHR-A and ETHR-B). Phylogenetic analysis showed that these receptors fall into a family of closely related GPCRs. We report for the first time the presence of putative ETHs and ETHRs in genomes of other arthropods, including the tick (Arachnida) and water flea (Crustacea). The possible source of ETH in ticks was detected in paired cells located in all pedal segments. Our results provide further evidence of structural and functional conservation of ETH-ETHR signaling. PMID:19951734

  11. Arthropod community structure on bark of koa (Acacia koa) and ʻōhiʻā (Metrosideros polymorpha) at Hakalau Forest National Wildlife Refuge, Hawaiʻi Island, Hawaiʻi

    USGS Publications Warehouse

    Peck, Robert W.; Banko, Paul C.; Stelmach, Matt

    2014-01-01

    The arthropod community associated with tree bark contains a wide variety of taxa but is poorly described, particularly in Hawaiʽi. Our overall goals were to evaluate the abundance of arthropods available to foraging birds and how variation in bark substrates may contribute to arthropod distributions in native forests. Our study aimed to identify this fauna on the dominant canopy-forming trees koa (Acacia koa) and ʽōhiʽa (Metrosideros polymorpha) within wet montane forest at Hakalau Forest National Wildlife Refuge, Hawaiʽi Island. At two sites roughly similar in elevation and habitat structure, we deployed three trap types designed to intercept arthropods moving along bark within tree canopies: a bole trap based on a pre-existing design and two traps specially designed for this study. Bole traps were placed on koa and ʽōhiʽa while branch traps were established on large and small branches of ʽōhiʽa. In total, 15 arthropod orders were identified, with Collembola most abundant (number/trap-day) generally followed by Isopoda and Araneae. Differences in abundance were found in some instances, but overall, few differences were detected between tree species or sites. Relative abundances of arthropod groups were also generally similar between trees and sites and among different parts of ʽōhiʽa. These results indicate that bark-dwelling arthropod communities are similar on koa and ʽōhiʽa, and birds should not develop strong preferences for gleaning arthropods from the bark of either species of tree based on prey availability.

  12. Entrapment Bias of Arthropods in Miocene Amber Revealed by Trapping Experiments in a Tropical Forest in Chiapas, Mexico

    PubMed Central

    Solórzano Kraemer, Mónica M.; Kraemer, Atahualpa S.; Stebner, Frauke; Bickel, Daniel J.; Rust, Jes

    2015-01-01

    All entomological traps have a capturing bias, and amber, viewed as a trap, is no exception. Thus the fauna trapped in amber does not represent the total existing fauna of the former amber forest, rather the fauna living in and around the resin producing tree. In this paper we compare arthropods from a forest very similar to the reconstruction of the Miocene Mexican amber forest, and determine the bias of different trapping methods, including amber. We also show, using cluster analyses, measurements of the trapped arthropods, and guild distribution, that the amber trap is a complex entomological trap not comparable with a single artificial trap. At the order level, the most similar trap to amber is the sticky trap. However, in the case of Diptera, at the family level, the Malaise trap is also very similar to amber. Amber captured a higher diversity of arthropods than each of the artificial traps, based on our study of Mexican amber from the Middle Miocene, a time of climate optimum, where temperature and humidity were probably higher than in modern Central America. We conclude that the size bias is qualitatively independent of the kind of trap for non–extreme values. We suggest that frequent specimens in amber were not necessarily the most frequent arthropods in the former amber forest. Selected taxa with higher numbers of specimens appear in amber because of their ecology and behavior, usually closely related with a tree–inhabiting life. Finally, changes of diversity from the Middle Miocene to Recent time in Central and South America can be analyzed by comparing the rich amber faunas from Mexico and the Dominican Republic with the fauna trapped using sticky and Malaise traps in Central America. PMID:25785584

  13. Potential and limitations of X-Ray micro-computed tomography in arthropod neuroanatomy: A methodological and comparative survey

    PubMed Central

    Sombke, Andy; Lipke, Elisabeth; Michalik, Peter; Uhl, Gabriele; Harzsch, Steffen

    2015-01-01

    Classical histology or immunohistochemistry combined with fluorescence or confocal laser scanning microscopy are common techniques in arthropod neuroanatomy, and these methods often require time-consuming and difficult dissections and sample preparations. Moreover, these methods are prone to artifacts due to compression and distortion of tissues, which often result in information loss and especially affect the spatial relationships of the examined parts of the nervous system in their natural anatomical context. Noninvasive approaches such as X-ray micro-computed tomography (micro-CT) can overcome such limitations and have been shown to be a valuable tool for understanding and visualizing internal anatomy and structural complexity. Nevertheless, knowledge about the potential of this method for analyzing the anatomy and organization of nervous systems, especially of taxa with smaller body size (e.g., many arthropods), is limited. This study set out to analyze the brains of selected arthropods with micro-CT, and to compare these results with available histological and immunohistochemical data. Specifically, we explored the influence of different sample preparation procedures. Our study shows that micro-CT is highly suitable for analyzing arthropod neuroarchitecture in situ and allows specific neuropils to be distinguished within the brain to extract quantitative data such as neuropil volumes. Moreover, data acquisition is considerably faster compared with many classical histological techniques. Thus, we conclude that micro-CT is highly suitable for targeting neuroanatomy, as it reduces the risk of artifacts and is faster than classical techniques. J. Comp. Neurol. 523:1281–1295, 2015. © 2015 Wiley Periodicals, Inc. PMID:25728683

  14. Arthropod surveillance programs: Basic components, strategies, and analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effective entomological surveillance planning stresses a careful consideration of methodology, trapping technologies, and analysis techniques. Herein, the basic principles and technological components of arthropod surveillance plans are described, as promoted in the symposium “Advancements in arthro...

  15. Nuisance arthropods, nonhost odors, and vertebrate chemical aposematism

    NASA Astrophysics Data System (ADS)

    Weldon, Paul J.

    2010-05-01

    Mosquitoes, ticks, and other ectoparasitic arthropods use chemoreception to avoid vertebrates that are known or presumed to be dangerous or otherwise unprofitable hosts. Nonhosts may belong to a species that is regularly unaccepted or one that includes both accepted and unaccepted individuals. A diverse array of qualities including immunocompetence, vigilant grooming behavior, mechanical inaccessibility, and toxicity have been proposed as the features that render vertebrate chemical emitters unsuitable as hosts for arthropods. In addition to advantages accrued by ectoparasitic arthropods that avoid nonhosts, vertebrates that are not accepted as hosts benefit by evading injurious ectoparasites and the infectious agents they transmit. The conferral of advantages to both chemical receivers (ectoparasitic arthropods) and emitters (unpreferred vertebrates) in these interactions renders nonhost odors aposematic. Chemical aposematism involving ectoparasites selects for vertebrates that emit distinctive odors. In addition, chemical mimicry, where vulnerable organisms benefit when misidentified as nonhosts, may be accommodated by duped ectoparasites.

  16. Insecticide-induced hormesis and arthropod pest management.

    PubMed

    Guedes, Raul Narciso C; Cutler, G Christopher

    2014-05-01

    Ecological backlashes such as insecticide resistance, resurgence and secondary pest outbreaks are frequent problems associated with insecticide use against arthropod pest species. The last two have been particularly important in sparking interest in the phenomenon of insecticide-induced hormesis within entomology and acarology. Hormesis describes a biphasic dose-response relationship that is characterized by a reversal of response between low and high doses of a stressor (e.g. insecticides). Although the concept of insecticide-induced hormesis often does not receive sufficient attention, or has been subject to semantic confusion, it has been reported in many arthropod pest species and natural enemies, and has been linked to pest outbreaks and potential problems with insecticide resistance. The study of hormesis remains largely neglected in entomology and acarology. Here, we examined the concept of insecticide-induced hormesis in arthropods, its functional basis and potential fitness consequences, and its importance in arthropod pest management and other areas. PMID:24155227

  17. Numerical Survey of Some Bacterial Taxa

    PubMed Central

    Focht, D. D.; Lockhart, W. R.

    1965-01-01

    Focht, D. D. (Iowa State University, Ames), and W. R. Lockhart. Numerical survey of some bacterial taxa. J. Bacteriol. 90:1314–1319. 1965.—A numerical analysis was made of 77 properties of each of 43 bacterial strains, representing 25 genera from 8 families in the orders Eubacteriales and Pseudomonadales. Four major groups were found, related to one another at approximately the same level of similarity: (1) a large cluster containing the subgroups (1a) Athiorhodaceae-Spirillaceae, (1b) Xanthomonas, and (1c) “inactive” Micrococcaceae-Achromobacteraceae; (2) a cluster containing the “active” Micrococcaceae and Lactobacillaceae; (3) the enterobacteria; and (4) Aeromonas. There was a sharp distinction between the branches of groups 1a, 1c, and 2. The composition of groups was essentially the same whether or not fermentation of carbohydrates (28 characters) was included in the analysis. Several individual strains, notably, Bacillus subtilis, Leuconostoc mesenteroides, Pseudomonas aeruginosa, and Erwinia amylovora, were related to none of the groups, and others (two species of Proteus, Flavobacterium devorans, and Lactobacillus casei) showed only minimal quantitative relationships with their groups. These results suggest that there may be significant variation in levels of similarity within microbial groups presently accorded equivalent taxonomic rank, and that some present distinctions among taxa, particularly at the generic level, cannot be confirmed on the basis of overall similarity. PMID:5848329

  18. One-step PCR amplification of complete arthropod mitochondrial genomes.

    PubMed

    Hwang, U W; Park, C J; Yong, T S; Kim, W

    2001-06-01

    A new PCR primer set which enables one-step amplification of complete arthropod mitochondrial genomes was designed from two conserved 16S rDNA regions for the long PCR technique. For this purpose, partial 16S rDNAs amplified with universal primers 16SA and 16SB were newly sequenced from six representative arthropods: Armadillidium vulgare and Macrobrachium nipponense (Crustacea), Anopheles sinensis (Insecta), Lithobius forficatus and Megaphyllum sp. (Myriapoda), and Limulus polyphemus (Chelicerata). The genomic locations of two new primers, HPK16Saa and HPK16Sbb, correspond to positions 13314-13345 and 12951-12984, respectively, in the Drosophila yakuba mitochondrial genome. The usefulness of the primer set was experimentally examined and confirmed with five of the representative arthropods, except for A. vulgare, which has a linearized mitochondrial genome. With this set, therefore, we could easily and rapidly amplify complete mitochondrial genomes with small amounts of arthropod DNA. Although the primers suggested here were examined only with arthropod groups, a possibility of successful application to other invertebrates is very high, since the high degree of sequence conservation is shown on the primer sites in other invertebrates. Thus, this primer set can serve various research fields, such as molecular evolution, population genetics, and molecular phylogenetics based on DNA sequences, RFLP, and gene rearrangement of mitochondrial genomes in arthropods and other invertebrates. PMID:11399145

  19. Administering and Detecting Protein Marks on Arthropods for Dispersal Research.

    PubMed

    Hagler, James R; Machtley, Scott A

    2016-01-01

    Monitoring arthropod movement is often required to better understand associated population dynamics, dispersal patterns, host plant preferences, and other ecological interactions. Arthropods are usually tracked in nature by tagging them with a unique mark and then re-collecting them over time and space to determine their dispersal capabilities. In addition to actual physical tags, such as colored dust or paint, various types of proteins have proven very effective for marking arthropods for ecological research. Proteins can be administered internally and/or externally. The proteins can then be detected on recaptured arthropods with a protein-specific enzyme-linked immunosorbent assay (ELISA). Here we describe protocols for externally and internally tagging arthropods with protein. Two simple experimental examples are demonstrated: (1) an internal protein mark introduced to an insect by providing a protein-enriched diet and (2) an external protein mark topically applied to an insect using a medical nebulizer. We then relate a step-by-step guide of the sandwich and indirect ELISA methods used to detect protein marks on the insects. In this demonstration, various aspects of the acquisition and detection of protein markers on arthropods for mark-release-recapture, mark-capture, and self-mark-capture types of research are discussed, along with the various ways that the immunomarking procedure has been adapted to suit a wide variety of research objectives. PMID:26863574

  20. Antiviral responses of arthropod vectors: an update on recent advances.

    PubMed

    Rückert, Claudia; Bell-Sakyi, Lesley; Fazakerley, John K; Fragkoudis, Rennos

    2014-01-01

    Arthropod vectors, such as mosquitoes, ticks, biting midges and sand flies, transmit many viruses that can cause outbreaks of disease in humans and animals around the world. Arthropod vector species are invading new areas due to globalisation and environmental changes, and contact between exotic animal species, humans and arthropod vectors is increasing, bringing with it the regular emergence of new arboviruses. For future strategies to control arbovirus transmission, it is important to improve our understanding of virus-vector interactions. In the last decade knowledge of arthropod antiviral immunity has increased rapidly. RNAi has been proposed as the most important antiviral response in mosquitoes and it is likely to be the most important antiviral response in all arthropods. However, other newly-discovered antiviral strategies such as melanisation and the link between RNAi and the JAK/STAT pathway via the cytokine Vago have been characterised in the last few years. This review aims to summarise the most important and most recent advances made in arthropod antiviral immunity. PMID:25674592

  1. The incidence of bacterial endosymbionts in terrestrial arthropods

    PubMed Central

    Weinert, Lucy A.; Araujo-Jnr, Eli V.; Ahmed, Muhammad Z.; Welch, John J.

    2015-01-01

    Intracellular endosymbiotic bacteria are found in many terrestrial arthropods and have a profound influence on host biology. A basic question about these symbionts is why they infect the hosts that they do, but estimating symbiont incidence (the proportion of potential host species that are actually infected) is complicated by dynamic or low prevalence infections. We develop a maximum-likelihood approach to estimating incidence, and testing hypotheses about its variation. We apply our method to a database of screens for bacterial symbionts, containing more than 3600 distinct arthropod species and more than 150 000 individual arthropods. After accounting for sampling bias, we estimate that 52% (CIs: 48–57) of arthropod species are infected with Wolbachia, 24% (CIs: 20–42) with Rickettsia and 13% (CIs: 13–55) with Cardinium. We then show that these differences stem from the significantly reduced incidence of Rickettsia and Cardinium in most hexapod orders, which might be explained by evolutionary differences in the arthropod immune response. Finally, we test the prediction that symbiont incidence should be higher in speciose host clades. But while some groups do show a trend for more infection in species-rich families, the correlations are generally weak and inconsistent. These results argue against a major role for parasitic symbionts in driving arthropod diversification. PMID:25904667

  2. Determining indicator taxa across spatial and seasonal gradients in the Columbia River coastal margin.

    PubMed

    Fortunato, Caroline S; Eiler, Alexander; Herfort, Lydie; Needoba, Joseph A; Peterson, Tawnya D; Crump, Byron C

    2013-10-01

    Bacterioplankton communities are deeply diverse and highly variable across space and time, but several recent studies demonstrate repeatable and predictable patterns in this diversity. We expanded on previous studies by determining patterns of variability in both individual taxa and bacterial communities across coastal environmental gradients. We surveyed bacterioplankton diversity across the Columbia River coastal margin, USA, using amplicon pyrosequencing of 16S rRNA genes from 596 water samples collected from 2007 to 2010. Our results showed seasonal shifts and annual reassembly of bacterioplankton communities in the freshwater-influenced Columbia River, estuary, and plume, and identified indicator taxa, including species from freshwater SAR11, Oceanospirillales, and Flavobacteria groups, that characterize the changing seasonal conditions in these environments. In the river and estuary, Actinobacteria and Betaproteobacteria indicator taxa correlated strongly with seasonal fluctuations in particulate organic carbon (ρ=-0.664) and residence time (ρ=0.512), respectively. In contrast, seasonal change in communities was not detected in the coastal ocean and varied more with the spatial variability of environmental factors including temperature and dissolved oxygen. Indicator taxa of coastal ocean environments included SAR406 and SUP05 taxa from the deep ocean, and Prochlorococcus and SAR11 taxa from the upper water column. We found that in the Columbia River coastal margin, freshwater-influenced environments were consistent and predictable, whereas coastal ocean community variability was difficult to interpret due to complex physical conditions. This study moves beyond beta-diversity patterns to focus on the occurrence of specific taxa and lends insight into the potential ecological roles these taxa have in coastal ocean environments. PMID:23719153

  3. Determining indicator taxa across spatial and seasonal gradients in the Columbia River coastal margin

    PubMed Central

    Fortunato, Caroline S; Eiler, Alexander; Herfort, Lydie; Needoba, Joseph A; Peterson, Tawnya D; Crump, Byron C

    2013-01-01

    Bacterioplankton communities are deeply diverse and highly variable across space and time, but several recent studies demonstrate repeatable and predictable patterns in this diversity. We expanded on previous studies by determining patterns of variability in both individual taxa and bacterial communities across coastal environmental gradients. We surveyed bacterioplankton diversity across the Columbia River coastal margin, USA, using amplicon pyrosequencing of 16S rRNA genes from 596 water samples collected from 2007 to 2010. Our results showed seasonal shifts and annual reassembly of bacterioplankton communities in the freshwater-influenced Columbia River, estuary, and plume, and identified indicator taxa, including species from freshwater SAR11, Oceanospirillales, and Flavobacteria groups, that characterize the changing seasonal conditions in these environments. In the river and estuary, Actinobacteria and Betaproteobacteria indicator taxa correlated strongly with seasonal fluctuations in particulate organic carbon (ρ=−0.664) and residence time (ρ=0.512), respectively. In contrast, seasonal change in communities was not detected in the coastal ocean and varied more with the spatial variability of environmental factors including temperature and dissolved oxygen. Indicator taxa of coastal ocean environments included SAR406 and SUP05 taxa from the deep ocean, and Prochlorococcus and SAR11 taxa from the upper water column. We found that in the Columbia River coastal margin, freshwater-influenced environments were consistent and predictable, whereas coastal ocean community variability was difficult to interpret due to complex physical conditions. This study moves beyond beta-diversity patterns to focus on the occurrence of specific taxa and lends insight into the potential ecological roles these taxa have in coastal ocean environments. PMID:23719153

  4. Microspectrophotometry of arthropod visual screening pigments.

    PubMed

    Strother, G K; Casella, A J

    1972-05-01

    Absorption spectra of visual screening pigments obtained in vitro with a microspectrophotometer using frozen sections are given for the insects Musca domestica, Phormia regina, Libellula luctuosa, Apis mellifera (worker honeybee only), Drosophila melanogaster (wild type only) and the arachnids Lycosa baltimoriana and Lycosa miami. The spectral range covered is 260-700 nm for Lycosa and Drosophila and 310-700 nm for the remainder of the arthropods. A complete description of the instrumentation is given. For the flies, Phormia and Musca, light absorption by the yellow and red pigments is high from 310 to about 610 nm. This implies that for these insects there should be no wavelength shift in electroretinogram (ERG) results due to light leakage among neighboring ommatidia for this wavelength range. The same comment applies to Calliphora erythrocephala, which is known to have similar screening pigments. For some of the insects studied a close correspondence is noted between screening pigment absorption spectra and spectral sensitivity curves for individual photoreceptors, available in the literature. In some cases the screening pigment absorption spectra can be related to chemical extraction results, with the general observation that some of the in vitro absorption peaks are shifted to the red. The Lycosa, Apis, and Libellula dark red pigments absorb strongly over a wide spectral range and therefore prevent chemical identification. PMID:4623852

  5. Diverse urban plantings managed with sufficient resource availability can increase plant productivity and arthropod diversity

    PubMed Central

    Muller, Jonathon N.; Loh, Susan; Braggion, Ligia; Cameron, Stephen; Firn, Jennifer L.

    2014-01-01

    Buildings structures and surfaces are explicitly being used to grow plants, and these “urban plantings” are generally designed for aesthetic value. Urban plantings also have the potential to contribute significant “ecological values” by increasing urban habitat for animals such as arthropods and by increasing plant productivity. In this study, we evaluated how the provision of these additional ecological values is affected by plant species richness; the availability of essential resources for plants, such as water, light, space; and soil characteristics. We sampled 33 plantings located on the exterior of three buildings in the urban center of Brisbane, Australia (subtropical climatic region) over 2, 6 week sampling periods characterized by different temperature and rainfall conditions. Plant cover was estimated as a surrogate for productivity as destructive sampling of biomass was not possible. We measured weekly light levels (photosynthetically active radiation), plant CO2 assimilation, soil CO2 efflux, and arthropod diversity. Differences in plant cover were best explained by a three-way interaction of plant species richness, management water regime and sampling period. As the richness of plant species increased in a planter, productivity and total arthropod richness also increased significantly—likely due to greater habitat heterogeneity and quality. Overall we found urban plantings can provide additional ecological values if essential resources are maintained within a planter such as water, light and soil temperature. Diverse urban plantings that are managed with these principles in mind can contribute to the attraction of diverse arthropod communities, and lead to increased plant productivity within a dense urban context. PMID:25400642

  6. Foundational issues concerning taxa and taxon names.

    PubMed

    Ereshefsky, Marc

    2007-04-01

    In a series of articles, Rieppel (2005, Biol. Philos. 20:465-487; 2006a, Cladistics 22:186-197; 2006b, Systematist 26:5-9), Keller et al. (2003, Bot. Rev. 69:93-110), and Nixon and Carpenter (2000, Cladistics 16:298-318) criticize the philosophical foundations of the PhyloCode. They argue that species and higher taxa are not individuals, and they reject the view that taxon names are rigid designators. Furthermore, they charge supporters of the individuality thesis and rigid designator theory with assuming essentialism, committing logical inconsistencies, and offering proposals that render taxonomy untestable. These charges are unsound. Such charges turn on confusions over rigid designator theory and the distinction between kinds and individuals. In addition, Rieppel's, Keller et al.'s, and Nixon and Carpenter's proposed alternatives are no better and have their own problems. The individuality thesis and rigid designator theory should not be quickly abandoned. PMID:17464884

  7. Arthropod community structure on strip-mined lands in Ohio

    SciTech Connect

    Urbanek, R.P.

    1982-01-01

    During 1978-79, biomass, density, diversity, and taxonomic composition of above-ground, non-acarine arthropods were studied on newly reclaimed areas planted to grass-legumes (1-4 years after reclamation), older mined lands planted to crown vetch (Coronilla varia L.) and unmined old field habitat in Harrison County, Ohio. The reclaimed areas were rapidly colonized and productive. In the herbaceous layer, newly reclaimed areas had highest annual arthropod densities (1062.5 individuals/m/sup 2/) and biomass (553.6 mg/m/sup 2/). Larvae of alfalfa weevil (Hypera postica Gyllenhal) were major contributors to arthropod density in the herbaceous layer during spring 1978, accounting for 47.4% and 18.8% of individuals on the areas examined 1 and 3 years after reclamation, respectively. During September, grasshoppers (Acrididae) accounted for up to 70% of arthropod biomass in the herbaceous layer on newly reclaimed areas. A significant decline in arthropod biomass from 1 to 2 years after reclamation was due to a large decrease in weevil and spittlebug (Philaenus spumarius L.) populations, associated with a decline in yellow sweet clover (Melilotus officinalis (L.) Lam.) and red clover (Trifolium pratense L.). The crown vetch area supported low numbers and biomass of arthropods in the herbaceous layer but moderate to high numbers and biomass in the litter layer. Nematoceran larvae (Cecidomyiidae, Chironomidae) were abundant during May on the area examined 2 years after reclamation and comprised 73.5% of litter arthropod individuals. The unmined old field was generally richer (48.0% more morphotypes, 32.2% more families per sampling period) than the mined sites. On newly reclaimed areas richness in the herbaceous layer was positively related to biomass of clovers.

  8. Ground-Dwelling Arthropod Communities of a Sky Island Mountain Range in Southeastern Arizona, USA: Obtaining a Baseline for Assessing the Effects of Climate Change.

    PubMed

    Meyer, Wallace M; Eble, Jeffrey A; Franklin, Kimberly; McManus, Reilly B; Brantley, Sandra L; Henkel, Jeff; Marek, Paul E; Hall, W Eugene; Olson, Carl A; McInroy, Ryan; Bernal Loaiza, Emmanuel M; Brusca, Richard C; Moore, Wendy

    2015-01-01

    The few studies that have addressed past effects of climate change on species distributions have mostly focused on plants due to the rarity of historical faunal baselines. However, hyperdiverse groups like Arthropoda are vital to monitor in order to understand climate change impacts on biodiversity. This is the first investigation of ground-dwelling arthropod (GDA) assemblages along the full elevation gradient of a mountain range in the Madrean Sky Island Region, establishing a baseline for monitoring future changes in GDA biodiversity. To determine how GDA assemblages relate to elevation, season, abiotic variables, and corresponding biomes, GDA were collected for two weeks in both spring (May) and summer (September) 2011 in the Santa Catalina Mountains, Arizona, using pitfall traps at 66 sites in six distinct upland (non-riparian/non-wet canyon) biomes. Four arthropod taxa: (1) beetles (Coleoptera), (2) spiders (Araneae), (3) grasshoppers and crickets (Orthoptera), and (4) millipedes and centipedes (Myriapoda) were assessed together and separately to determine if there are similar patterns across taxonomic groups. We collected 335 species of GDA: 192/3793 (species/specimens) Coleoptera, 102/1329 Araneae, 25/523 Orthoptera, and 16/697 Myriapoda. GDA assemblages differed among all biomes and between seasons. Fifty-three percent (178 species) and 76% (254 species) of all GDA species were found in only one biome and during only one season, respectively. While composition of arthropod assemblages is tied to biome and season, individual groups do not show fully concordant patterns. Seventeen percent of the GDA species occurred only in the two highest-elevation biomes (Pine and Mixed Conifer Forests). Because these high elevation biomes are most threatened by climate change and they harbor a large percentage of unique arthropod species (11-25% depending on taxon), significant loss in arthropod diversity is likely in the Santa Catalina Mountains and other isolated

  9. Ground-Dwelling Arthropod Communities of a Sky Island Mountain Range in Southeastern Arizona, USA: Obtaining a Baseline for Assessing the Effects of Climate Change

    PubMed Central

    Meyer, Wallace M.; Eble, Jeffrey A.; Franklin, Kimberly; McManus, Reilly B.; Brantley, Sandra L.; Henkel, Jeff; Marek, Paul E.; Hall, W. Eugene; Olson, Carl A.; McInroy, Ryan; Bernal Loaiza, Emmanuel M.; Brusca, Richard C.; Moore, Wendy

    2015-01-01

    The few studies that have addressed past effects of climate change on species distributions have mostly focused on plants due to the rarity of historical faunal baselines. However, hyperdiverse groups like Arthropoda are vital to monitor in order to understand climate change impacts on biodiversity. This is the first investigation of ground-dwelling arthropod (GDA) assemblages along the full elevation gradient of a mountain range in the Madrean Sky Island Region, establishing a baseline for monitoring future changes in GDA biodiversity. To determine how GDA assemblages relate to elevation, season, abiotic variables, and corresponding biomes, GDA were collected for two weeks in both spring (May) and summer (September) 2011 in the Santa Catalina Mountains, Arizona, using pitfall traps at 66 sites in six distinct upland (non-riparian/non-wet canyon) biomes. Four arthropod taxa: (1) beetles (Coleoptera), (2) spiders (Araneae), (3) grasshoppers and crickets (Orthoptera), and (4) millipedes and centipedes (Myriapoda) were assessed together and separately to determine if there are similar patterns across taxonomic groups. We collected 335 species of GDA: 192/3793 (species/specimens) Coleoptera, 102/1329 Araneae, 25/523 Orthoptera, and 16/697 Myriapoda. GDA assemblages differed among all biomes and between seasons. Fifty-three percent (178 species) and 76% (254 species) of all GDA species were found in only one biome and during only one season, respectively. While composition of arthropod assemblages is tied to biome and season, individual groups do not show fully concordant patterns. Seventeen percent of the GDA species occurred only in the two highest-elevation biomes (Pine and Mixed Conifer Forests). Because these high elevation biomes are most threatened by climate change and they harbor a large percentage of unique arthropod species (11–25% depending on taxon), significant loss in arthropod diversity is likely in the Santa Catalina Mountains and other isolated

  10. Embryonic neurogenesis in Pseudopallene sp. (Arthropoda, Pycnogonida) includes two subsequent phases with similarities to different arthropod groups

    PubMed Central

    2013-01-01

    sp. combines features of central nervous system development that have been hitherto described separately in different arthropod taxa. The two-phase character of pycnogonid neurogenesis calls for a thorough reinvestigation of other non-model arthropods over the entire course of neurogenesis. With the currently available data, a common origin of pycnogonid neural stem cells and tetraconate neuroblasts remains unresolved. To acknowledge this, we present two possible scenarios on the evolution of arthropod neurogenesis, whereby Myriapoda play a key role in the resolution of this issue. PMID:24289241

  11. Skimming the surface with Burgess Shale arthropod locomotion

    PubMed Central

    Minter, Nicholas J.; Mángano, M. Gabriela; Caron, Jean-Bernard

    2012-01-01

    The first arthropod trackways are described from the Middle Cambrian Burgess Shale Formation of Canada. Trace fossils, including trackways, provide a rich source of biological and ecological information, including direct evidence of behaviour not commonly available from body fossils alone. The discovery of large arthropod trackways is unique for Burgess Shale-type deposits. Trackway dimensions and the requisite number of limbs are matched with the body plan of a tegopeltid arthropod. Tegopelte, one of the rarest Burgess Shale animals, is over twice the size of all other benthic arthropods known from this locality, and only its sister taxon, Saperion, from the Lower Cambrian Chengjiang biota of China, approaches a similar size. Biomechanical trackway analysis demonstrates that tegopeltids were capable of rapidly skimming across the seafloor and, in conjunction with the identification of gut diverticulae in Tegopelte, supports previous hypotheses on the locomotory capabilities and carnivorous mode of life of such arthropods. The trackways occur in the oldest part (Kicking Horse Shale Member) of the Burgess Shale Formation, which is also known for its scarce assemblage of soft-bodied organisms, and indicate at least intermittent oxygenated bottom waters and low sedimentation rates. PMID:22072605

  12. Exoskeletons and economics: indoor arthropod diversity increases in affluent neighbourhoods.

    PubMed

    Leong, Misha; Bertone, Matthew A; Bayless, Keith M; Dunn, Robert R; Trautwein, Michelle D

    2016-08-01

    In urban ecosystems, socioeconomics contribute to patterns of biodiversity. The 'luxury effect', in which wealthier neighbourhoods are more biologically diverse, has been observed for plants, birds, bats and lizards. Here, we used data from a survey of indoor arthropod diversity (defined throughout as family-level richness) from 50 urban houses and found that house size, surrounding vegetation, as well as mean neighbourhood income best predict the number of kinds of arthropods found indoors. Our finding, that homes in wealthier neighbourhoods host higher indoor arthropod diversity (consisting of primarily non-pest species), shows that the luxury effect can extend to the indoor environment. The effect of mean neighbourhood income on indoor arthropod diversity was particularly strong for individual houses that lacked high surrounding vegetation ground cover, suggesting that neighbourhood dynamics can compensate for local choices of homeowners. Our work suggests that the management of neighbourhoods and cities can have effects on biodiversity that can extend from trees and birds all the way to the arthropod life in bedrooms and basements. PMID:27484644

  13. The non-target impact of spinosyns on beneficial arthropods.

    PubMed

    Biondi, Antonio; Mommaerts, Veerle; Smagghe, Guy; Viñuela, Elisa; Zappalà, Lucia; Desneux, Nicolas

    2012-12-01

    Spinosyn-based products, mostly spinosad, have been widely recommended by extension specialists and agribusiness companies; consequently, they have been used to control various pests in many different cropping systems. Following the worldwide adoption of spinosad-based products for integrated and organic farming, an increasing number of ecotoxicological studies have been published in the past 10 years. These studies are primarily related to the risk assessment of spinosad towards beneficial arthropods. This review takes into account recent data with the aim of (i) highlighting potentially adverse effects of spinosyns on beneficial arthropods (and hence on ecosystem services that they provide in agroecosystems), (ii) clarifying the range of methods used to address spinosyn side effects on biocontrol agents and pollinators in order to provide new insights for the development of more accurate bioassays, (iii) identifying pitfalls when analysing laboratory results to assess field risks and (iv) gaining increasing knowledge on side effects when using spinosad for integrated pest management (IPM) programmes and organic farming. For the first time, a thorough review of possible risks of spinosad and novel spinosyns (such as spinetoram) to beneficial arthropods (notably natural enemies and pollinators) is provided. The acute lethal effect and multiple sublethal effects have been identified in almost all arthropod groups studied. This review will help to optimise the future use of spinosad and new spinosyns in IPM programmes and for organic farming, notably by preventing the possible side effects of spinosyns on beneficial arthropods. PMID:23109262

  14. The organic preservation of fossil arthropods: an experimental study

    PubMed Central

    Gupta, Neal S; Michels, R; Briggs, Derek E.G; Evershed, Richard P; Pancost, Richard D

    2006-01-01

    Modern arthropod cuticles consist of chitin fibres in a protein matrix, but those of fossil arthropods with an organic exoskeleton, particularly older than Tertiary, contain a dominant aliphatic component. This apparent contradiction was examined by subjecting modern cockroach, scorpion and shrimp cuticle to artificial maturation (350 °C/700 bars/24 h) following various chemical treatments, and analysing the products with pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS). Analysis of artificially matured untreated cuticle yielded moieties related to phenols and alkylated substituents, pyridines, pyrroles and possibly indenes (derived from chitin). n-Alkyl amides, C16 and C18 fatty acids and alkane/alk-1-ene homologues ranging from C9 to C19 were also generated, the last indicating the presence of an n-alkyl component, similar in composition to that encountered in fossil arthropods. Similar pyrolysates were obtained from matured pure C16 and C18 fatty acids. Py–GC/MS of cuticles matured after lipid extraction and hydrolysis did not yield any aliphatic polymer. This provides direct experimental evidence that lipids incorporated from the cuticle were the source of aliphatic polymer. This process of in situ polymerization appears to account for most of the fossil record of terrestrial arthropods as well as marine arthropods that lacked a biomineralized exoskeleton. PMID:17015325

  15. Does oxygen limit thermal tolerance in arthropods? A critical review of current evidence

    PubMed Central

    Verberk, Wilco C.E.P.; Overgaard, Johannes; Ern, Rasmus; Bayley, Mark; Wang, Tobias; Boardman, Leigh; Terblanche, John S.

    2016-01-01

    decreases near critical temperatures, a key feature of the OCLTT hypothesis. In air-breathers, only severe hypoxia (< 2 kPa) affected heat tolerance. The discrepancies for heat tolerance between aquatic and terrestrial organisms can to some extent be reconciled by differences in the capacity to increase oxygen transport. As air-breathing arthropods are unlikely to become oxygen limited under normoxia (especially at rest), the oxygen limitation component in OCLTT does not seem to provide sufficient information to explain lethal temperatures. Nevertheless, many animals may simultaneously face hypoxia and thermal extremes and the combination of these potential stressors is particularly relevant for aquatic organisms where hypoxia (and hyperoxia) is more prevalent. In conclusion, whether taxa show oxygen limitation at thermal extremes may be contingent on their capacity to regulate oxygen uptake, which in turn is linked to their respiratory medium (air vs. water). Fruitful directions for future research include testing multiple predictions of OCLTT in the same species. Additionally, we call for greater research efforts towards studying the role of oxygen in thermal limitation of animal performance at less extreme, sub-lethal temperatures, necessitating studies over longer timescales and evaluating whether oxygen becomes limiting for animals to meet energetic demands associated with feeding, digestion and locomotion. PMID:26506130

  16. Does oxygen limit thermal tolerance in arthropods? A critical review of current evidence.

    PubMed

    Verberk, Wilco C E P; Overgaard, Johannes; Ern, Rasmus; Bayley, Mark; Wang, Tobias; Boardman, Leigh; Terblanche, John S

    2016-02-01

    decreases near critical temperatures, a key feature of the OCLTT hypothesis. In air-breathers, only severe hypoxia (<2 kPa) affected heat tolerance. The discrepancies for heat tolerance between aquatic and terrestrial organisms can to some extent be reconciled by differences in the capacity to increase oxygen transport. As air-breathing arthropods are unlikely to become oxygen limited under normoxia (especially at rest), the oxygen limitation component in OCLTT does not seem to provide sufficient information to explain lethal temperatures. Nevertheless, many animals may simultaneously face hypoxia and thermal extremes and the combination of these potential stressors is particularly relevant for aquatic organisms where hypoxia (and hyperoxia) is more prevalent. In conclusion, whether taxa show oxygen limitation at thermal extremes may be contingent on their capacity to regulate oxygen uptake, which in turn is linked to their respiratory medium (air vs. water). Fruitful directions for future research include testing multiple predictions of OCLTT in the same species. Additionally, we call for greater research efforts towards studying the role of oxygen in thermal limitation of animal performance at less extreme, sub-lethal temperatures, necessitating studies over longer timescales and evaluating whether oxygen becomes limiting for animals to meet energetic demands associated with feeding, digestion and locomotion. PMID:26506130

  17. Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants

    PubMed Central

    Hellmich, Richard L.; Candolfi, Marco P.; Carstens, Keri; De Schrijver, Adinda; Gatehouse, Angharad M. R.; Herman, Rod A.; Huesing, Joseph E.; McLean, Morven A.; Raybould, Alan; Shelton, Anthony M.; Waggoner, Annabel

    2010-01-01

    This paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (GE) plants on non-target arthropods (NTAs). While we rely heavily on the currently used proteins from Bacillus thuringiensis (Bt) in this discussion, the concepts apply to other arthropod-active proteins. A risk may exist if the newly acquired trait of the GE plant has adverse effects on NTAs when they are exposed to the arthropod-active protein. Typically, the risk assessment follows a tiered approach that starts with laboratory studies under worst-case exposure conditions; such studies have a high ability to detect adverse effects on non-target species. Clear guidance on how such data are produced in laboratory studies assists the product developers and risk assessors. The studies should be reproducible and test clearly defined risk hypotheses. These properties contribute to the robustness of, and confidence in, environmental risk assessments for GE plants. Data from NTA studies, collected during the analysis phase of an environmental risk assessment, are critical to the outcome of the assessment and ultimately the decision taken by regulatory authorities on the release of a GE plant. Confidence in the results of early-tier laboratory studies is a precondition for the acceptance of data across regulatory jurisdictions and should encourage agencies to share useful information and thus avoid redundant testing. PMID:20938806

  18. Découverte d'Arthropodes et de bivalves inédits dans le Permien continental (Lodévois, France)

    NASA Astrophysics Data System (ADS)

    Gand, Georges; Lapeyrie, Jean; Garric, Jacques; Nel, André; Schneider, Jörg; Walter, Harald

    1997-12-01

    Triopsids, Conchostracans, Insects, non-marine Bivalve shells, Arthropod tracks and burrows are reported for the first time in the Saxonian Group which was long thought to be unfossiliferous. Virtually none of these fossils have been described at the species, family or even order rank. Some new insect taxa fill time gaps between the Permian and the Jurassic. Future information about Insects promises to be a useful tool for testing certain phylogenetic assumptions and evaluating the true scale of the Permo-Triassic mass extinction for this class. Insects and Conchostracans indicate a Kungurian to Tatarian age (Leonardian to Capitanian) for the Saxonian fades.

  19. Subdivision of arthropod cap-n-collar expression domains is restricted to Mandibulata

    PubMed Central

    2014-01-01

    Background The monophyly of Mandibulata - the division of arthropods uniting pancrustaceans and myriapods - is consistent with several morphological characters, such as the presence of sensory appendages called antennae and the eponymous biting appendage, the mandible. Functional studies have demonstrated that the patterning of the mandible requires the activity of the Hox gene Deformed and the transcription factor cap-n-collar (cnc) in at least two holometabolous insects: the fruit fly Drosophila melanogaster and the beetle Tribolium castaneum. Expression patterns of cnc from two non-holometabolous insects and a millipede have suggested conservation of the labral and mandibular domains within Mandibulata. However, the activity of cnc is unknown in crustaceans and chelicerates, precluding understanding of a complete scenario for the evolution of patterning of this appendage within arthropods. To redress these lacunae, here we investigate the gene expression of the ortholog of cnc in Parhyale hawaiensis, a malacostracan crustacean, and two chelicerates: the harvestman Phalangium opilio, and the scorpion Centruroides sculpturatus. Results In the crustacean P. hawaiensis, the segmental expression of Ph-cnc is the same as that reported previously in hexapods and myriapods, with two distinct head domains in the labrum and the mandibular segment. In contrast, Po-cnc and Cs-cnc expression is not enriched in the labrum of either chelicerate, but instead is expressed at comparable levels in all appendages. In further contrast to mandibulate orthologs, the expression domain of Po-cnc posterior to the labrum is not confined within the expression domain of Po-Dfd. Conclusions Expression data from two chelicerate outgroup taxa suggest that the signature two-domain head expression pattern of cnc evolved at the base of Mandibulata. The observation of the archetypal labral and mandibular segment domains in a crustacean exemplar supports the synapomorphic nature of mandibulate cnc

  20. Arthropods and their products as aphrodisiacs--review of literature.

    PubMed

    Pajovic, B; Radosavljevic, M; Radunovic, M; Radojevic, N; Bjelogrlic, B

    2012-04-01

    After a short review of impotence, the definitions of erectants and aphrodisiacs are presented. The Authors propose division of arthropods according to the places of effect. The description of particular arthropods with their pictures and nomenclature, is followed by certain or probable mechanisms of achieving the aphrodisiac and sometimes toxic effect, that were available in the literature since 1929 till nowadays. We mention the most usual locations, mainly in Asia, where they are found and consumed, but also, we describe the manner of preparing and intake. The review includes the following arthropods: lobster, Arizona bark scorpion, deathstalker, banana spider, Mediterranean black widow, Burmeister's triatoma, giant water bug, diving-beetle, Korean bug, diaclina, flannel moth, Spanish fly, migratory locust, red wood ant and honeybee. PMID:22696884

  1. Species identity influences belowground arthropod assemblages via functional traits

    PubMed Central

    Gorman, Courtney E.; Read, Quentin D.; Van Nuland, Michael E.; Bryant, Jessica A. M.; Welch, Jessica N.; Altobelli, Joseph T.; Douglas, Morgan J.; Genung, Mark A.; Haag, Elliot N.; Jones, Devin N.; Long, Hannah E.; Wilburn, Adam D.; Schweitzer, Jennifer A.; Bailey, Joseph K.

    2013-01-01

    Plant species influence belowground communities in a variety of ways, ultimately impacting nutrient cycling. Functional plant traits provide a means whereby species identity can influence belowground community interactions, but little work has examined whether species identity influences belowground community processes when correcting for evolutionary history. Specifically, we hypothesized that closely related species would exhibit (i) more similar leaf and root functional traits than more distantly related species, and (ii) more similar associated soil arthropod communities. We found that after correcting for evolutionary history, tree species identity influenced belowground arthropod communities through plant functional traits. These data suggest that plant species structure may be an important predictor in shaping associated soil arthropod communities and further suggest the importance of better understanding the extended consequences of evolutionary history on ecological processes, as similarity in traits may not always reflect similar ecology.

  2. Inbreeding and the evolution of sociality in arthropods

    NASA Astrophysics Data System (ADS)

    Tabadkani, Seyed Mohammad; Nozari, Jamasb; Lihoreau, Mathieu

    2012-10-01

    Animals have evolved strategies to optimally balance costs and benefits of inbreeding. In social species, these adaptations can have a considerable impact on the structure, the organization, and the functioning of groups. Here, we consider how selection for inbreeding avoidance fashions the social behavior of arthropods, a phylum exhibiting an unparalleled richness of social lifestyles. We first examine life histories and parental investment patterns determining whether individuals should actively avoid or prefer inbreeding. Next, we illustrate the diversity of inbreeding avoidance mechanisms in arthropods, from the dispersal of individuals to the rejection of kin during mate choice and the production of unisexual broods by females. Then, we address the particular case of haplodiploid insects. Finally, we discuss how inbreeding may drive and shape the evolution of arthropods societies along two theoretical pathways.

  3. Molecular bases of proliferation of Francisella tularensis in Arthropod vectors

    PubMed Central

    Asare, Rexford; Akimana, Christine; Jones, Snake; Kwaik, Yousef Abu

    2010-01-01

    Summary Arthropod vectors are important vehicles for transmission of Francisella tularensis between mammals, but very little is known about the F. tularensis-arthropod vector interaction. Drosophila melanogaster has been recently developed as an arthropod vector model for F. tularensis. We have shown that intracellular trafficking of F. tularensis within human monocytes-derived macrophages and D. melanogaster-derived S2 cells is very similar. Within both evolutionarily distant host cells, the Francisella-containing phagosome matures to a late endosome-like phagosome with limited fusion to lysosomes followed by rapid bacterial escape into the cytosol where the bacterial proliferate. To decipher the molecular bases of intracellular proliferation of F. tularensis within arthropod-derived cells, we screened a comprehensive library of mutants of F. tularensis subsp novicida for their defect in intracellular proliferation within D. melanogaster-derived S2 cells. Our data show that 394 genes, representing 22% of the genome, are required for intracellular proliferation within D. melanogaster-derived S2 cells, including many of the Francisella Pathogenicity Island (FPI) genes that are also required for proliferation within mammalian macrophages. Functional gene classes that exhibit growth defect include metabolic (25%), FPI (2%), Type IV pili (1%), transport (16%) and DNA modification (5%). Among 168 most defective mutants in intracellular proliferation in S2 cells, 80 are defective in lethality and proliferation within adult D. melanogaster. The observation that only 135 of the 394 mutants that are defective in S2 cells are also defective in human macrophages indicates that F. tularensis utilize common as well as distinct mechanisms to proliferate within mammalian and arthropod cells. Our studies will facilitate deciphering the molecular aspects of F. tularensis-arthropod vector interaction and its patho-adaptation to infect mammals. PMID:20482589

  4. [2013 update about arthropod envenomations in French Guyana].

    PubMed

    Ganteaume, F; Imbert, C

    2014-02-01

    French Guiana, by its geographical situation, its climate and its biodiversity, is often called "the green hell". Indeed, this French department of America shelters a wildlife rich, abundant among which many species of arthropods, some of which are responsible for envenomations. These accidents consist of scorpion's or hymenoptera's stings or spider's bites. The associated clinical aspect is variable, from simple pain to circulatory collapse, or lung oedema. However, symptomatology is generally mild; four deaths associated to arthropod envenomations have been reported in the past 25 years. This article focuses on envenomations in French Guiana, describing favoring human behavior, risks and venoms associated with the main related animal species. PMID:24415535

  5. The endoskeletal structures in arthropods: cytology, morphology and evolution.

    PubMed

    Bitsch, Colette; Bitsch, Jacques

    2002-02-01

    The paper proposes an overview of the endoskeletal structures of the head and trunk in the different arthropod groups: Chelicerata, Crustacea, Myriapoda and Hexapoda (=Insecta s.l.). Two major endoskeletal systems are reported with their cytological characteristics: those made up of connective tissue derived from muscular tendons, and those consisting of cuticular rods or plates arising from integumentary ingrowths. The morphological value of the various endoskeletal structures, their possible homologies in different groups, and their presumed evolutionary changes are discussed. This survey may be considered as a first step to use morphological characteristics of the endoskeleton in future cladistic analyses to assess the phylogeny of arthropods. PMID:18088953

  6. The Ground-Dwelling Arthropod Community of Península Valdés in Patagonia, Argentina

    PubMed Central

    Cheli, Germán H.; Corley, J. C.; Bruzzone, O.; del Brío, M.; Martínez, F.; Román, N. Martínez; Ríos, I.

    2010-01-01

    This is the first study based on a planned and intensive sampling effort that describes the community composition and structure of the ground-dwelling arthropod assemblage of Península Valdés (Patagonia). It was carried out using pitfall traps, opened for two weeks during the summers of 2005, 2006 and 2007. A total of 28, 111 individuals were caught. Ants (Hymenoptera: Formicidae) dominated this community, followed by beetles (Coleoptera) and spiders (Araneae). The most abundant species were Pheidole bergi Mayr (Hymenoptera: Formicidae) and Blapstinus punctulatus Solier (Coleoptera: Tenebrionidae). Two new species were very recently described as new based on specimens collected during this study: Valdesiana curiosa Carpintero, Dellapé & Cheli (Hemiptera, Miridae) and Anomaloptera patagonica Dellapé & Cheli (Hemiptera, Oxycarenidae). The order Coleoptera was the most diverse taxa. The distribution of abundance data was best described by the logarithmic series model both at the family and species levels, suggesting that ecological relationships in this community could be controlled by a few factors. The community was dominated by predators from a trophic perspective. This suggests that predation acts as an important factor driving the distribution and abundances of surface-dwelling arthropods in this habitat and as such serves as a key element in understanding desert, above-ground community structure. These findings may also be useful for management and conservation purposes in arid Patagonia. PMID:20572783

  7. The ground-dwelling arthropod community of Península Valdés in Patagonia, Argentina.

    PubMed

    Cheli, Germán H; Corley, J C; Bruzzone, O; Brío, M Del; Martínez, F; Román, N Martínez; Ríos, I

    2010-01-01

    This is the first study based on a planned and intensive sampling effort that describes the community composition and structure of the ground-dwelling arthropod assemblage of Península Valdés (Patagonia). It was carried out using pitfall traps, opened for two weeks during the summers of 2005, 2006 and 2007. A total of 28,111 individuals were caught. Ants(Hymenoptera: Formicidae) dominated this community, followed by beetles (Coleoptera) and spiders (Araneae). The most abundant species were Pheidole bergi Mayr (Hymenoptera:Formicidae) and Blapstinus punctulatus Solier (Coleoptera: Tenebrionidae). Two new species were very recently described as new based on specimens collected during this study: Valdesianacuriosa Carpintero, Dellapé & Cheli (Hemiptera, Miridae) and Anomaloptera patagonica Dellapé& Cheli (Hemiptera, Oxycarenidae). The order Coleoptera was the most diverse taxa. The distribution of abundance data was best described by the logarithmic series model both at the family and species levels, suggesting that ecological relationships in this community could be controlled by a few factors. The community was dominated by predators from a trophic perspective. This suggests that predation acts as an important factor driving the distribution and abundances of surface-dwelling arthropods in this habitat and as such serves as a key element in understanding desert, above-ground community structure. These findings may also be useful for management and conservation purposes in arid Patagonia. PMID:20572783

  8. Diet of Wilson's warblers and distribution of arthropod prey in the understory of Douglas-fir forests

    USGS Publications Warehouse

    Hagar, Joan C.; Dugger, Kate; Starkey, Edward E.

    2007-01-01

    Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wilson's Warblers (Wilsonia pusilla) that foraged in the understory of Douglas-fir (Pseudotsuga menziesii) forests in western Oregon during the breeding season. We sampled arthropods at the same sites where diet data were collected, and compared abundance and biomass of prey among seven common shrub species. Wilson's Warblers ate more caterpillars (Lepidoptera larvae), flies (Diptera), beetles (Coleoptera), and Homoptera than expected based on availability. Deciduous shrubs supported higher abundances of arthropod taxa and size classes used as prey by Wilson's Warblers than did evergreen shrubs. The development and maintenance of deciduous understory vegetation in conifer forests of the Pacific Northwest may be fundamental for conservation of food webs that support breeding Wilson's Warblers and other shrub-associated, insectivorous songbirds.

  9. 40 CFR 180.1124 - Arthropod pheromones; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably...

  10. 40 CFR 180.1124 - Arthropod pheromones; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably...

  11. 40 CFR 180.1124 - Arthropod pheromones; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably...

  12. 40 CFR 180.1124 - Arthropod pheromones; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably...

  13. 40 CFR 180.1124 - Arthropod pheromones; exemption from the requirement of a tolerance.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably...

  14. Twelve invasive plant taxa in U.S. western riparian ecosystems

    EPA Science Inventory

    Assessments of stream ecosystems often include an evaluation of riparian condition; a key stressor in riparian ecosystems is the presence of invasive plants. We analyzed the distribution of 12 invasive taxa (common burdock [Arctium minus], giant reed [Arundo donax], cheatgrass [B...

  15. Ecological stoichiometry and density responses of plant-arthropod communities on cormorant nesting islands.

    PubMed

    Kolb, Gundula S; Palmborg, Cecilia; Hambäck, Peter A

    2013-01-01

    Seabirds deposit large amounts of nutrient rich guano on their nesting islands. The increased nutrient availability strongly affects plants and consumers. Consumer response differs among taxonomic groups, but mechanisms causing these differences are poorly understood. Ecological stoichiometry might provide tools to understand these mechanisms. ES suggests that nutrient rich taxa are more likely to be nutrient limited than nutrient poorer taxa and are more favored under nutrient enrichment. Here, we quantified differences in the elemental composition of soil, plants, and consumers between islands with and without nesting cormorant colonies and tested predictions made based on ES by relating the elemental composition and the eventual mismatch between consumer and resource stoichiometry to observed density differences among the island categories. We found that nesting cormorants radically changed the soil nutrient content and thereby indirectly plant nutrient content and resource quality to herbivores. In contrast, consumers showed only small differences in their elemental composition among the island categories. While we cannot evaluate the cause of the apparent homeostasis of invertebrates without additional data, we can conclude that from the perspective of the next trophic level, there is no difference in diet quality (in terms of N and P content) between island categories. Thus, bottom-up effects seemed mainly be mediated via changes in resource quantity not quality. Despite a large potential trophic mismatch we were unable to observe any relation between the invertebrate stoichiometry and their density response to nesting cormorant colonies. We conclude that in our system stoichiometry is not a useful predictor of arthropod responses to variation in resource nutrient content. Furthermore, we found no strong evidence that resource quality was a prime determinant of invertebrate densities. Other factors like resource quantity, habitat structure and species

  16. Diet-consumer nitrogen isotope fractionation for prolonged fasting arthropods.

    PubMed

    Mizota, Chitoshi; Yamanaka, Toshiro

    2011-12-01

    Nitrogen acquisition for cellular metabolism during diapause is a primary concern for herbivorous arthropods. Analyses of naturally occurring stable isotopes of nitrogen help elucidate the mechanism. Relevant articles have cited (58 times up to mid-June 2011) anomalously elevated δ(15)N (per mil deviation of (15)N/(14)N, relative to atmospheric nitrogen=0 ‰) values (diet-consumer nitrogen isotope fractionation; up to 12 ‰) for a prolonged fasting raspberry beetle (Byturus tomentosus Degeer (Coleoptera: Byturidae)), which feeds on red raspberries (Rubus idaeus: δ(15)N= ~ +2 ‰). Biologists have hypothesised that extensive recycling of amino acid nitrogen is responsible for the prolonged fasting. Since this hypothesis was proposed in 1995, scientists have integrated biochemical and molecular knowledge to support the mechanism of prolonged diapausing of animals. To test the validity of the recycling hypothesis, we analysed tissue nitrogen isotope ratios for four Japanese arthropods: the shield bug Parastrachia japonensis Scott (Hemiptera: Cydnidae), the burrower bug Canthophorus niveimarginatus Scott (Hemiptera: Cydnidae), leaf beetle Gastrophysa atrocyanea Motschulsky (Coleoptera: Chrysomelidae) and the Japanese oak silkworm Antheraea yamamai (Lepidoptera: Saturniidae), all of which fast for more than 6 months as part of their life-history strategy. Resulting diet-consumer nitrogen isotope discrimination during fasting ranged from 0 to 7‰, as in many commonly known terrestrial arthropods. We conclude that prolonged fasting of arthropods does not always result in anomalous diet-consumer nitrogen isotope fractionation, since the recycling process is closed or nearly closed with respect to nitrogen isotopes. PMID:22166153

  17. Microbial control of arthropod pests of tropical tree fruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microbial control agents (virus, bacteria, fungi, and nematodes) have been developed as alternative control methods of a wide variety of arthropod pests of a number of crops including tropical fruit. The majority of research and application in tropical fruit agroecosystems has been conducted in citr...

  18. Control of arthropod pests of tropical tree fruit with entomopathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A plethora of arthropods attack fruit crops throughout the tropics and sub-tropics. The predominant method for controlling most of these pests is the application of broad-spectrum chemical pesticides. Growing concern over the negative environmental effects has encouraged development of alternative c...

  19. Successive Gain of Insulator Proteins in Arthropod Evolution

    PubMed Central

    Heger, Peter; George, Rebecca; Wiehe, Thomas

    2013-01-01

    Alteration of regulatory DNA elements or their binding proteins may have drastic consequences for morphological evolution. Chromatin insulators are one example of such proteins and play a fundamental role in organizing gene expression. While a single insulator protein, CTCF (CCCTC-binding factor), is known in vertebrates, Drosophila melanogaster utilizes six additional factors. We studied the evolution of these proteins and show here that—in contrast to the bilaterian-wide distribution of CTCF—all other D. melanogaster insulators are restricted to arthropods. The full set is present exclusively in the genus Drosophila whereas only two insulators, Su(Hw) and CTCF, existed at the base of the arthropod clade and all additional factors have been acquired successively at later stages. Secondary loss of factors in some lineages further led to the presence of different insulator subsets in arthropods. Thus, the evolution of insulator proteins within arthropods is an ongoing and dynamic process that reshapes and supplements the ancient CTCF-based system common to bilaterians. Expansion of insulator systems may therefore be a general strategy to increase an organism’s gene regulatory repertoire and its potential for morphological plasticity. PMID:24094345

  20. Book Review: Bioassays with Arthropods: 2nd Edition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The technical book "Bioassays with Arthropods: 2nd Edition" (2007. Jacqueline L. Robertson, Robert M. Russell, Haiganoush K, Preisler and N. E. Nevin, Eds. CRC Press, Boca Raton, FL, 224 pp.) was reviewed for the scientific readership of the peer-reviewed publication Journal of Economic Entomology. ...

  1. Manipulation of arthropod pathogens for integrated pest management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A great diversity of pathogenic microorganisms and nematodes has been developed for microbial biological control of insect and other arthropod pests. These control agents have many characteristics that determine their capacities to provide reliable pest control, and these characteristics must be ta...

  2. Horizontal Gene Transfer Contributes to the Evolution of Arthropod Herbivory

    PubMed Central

    Wybouw, Nicky; Pauchet, Yannick; Heckel, David G.; Van Leeuwen, Thomas

    2016-01-01

    Within animals, evolutionary transition toward herbivory is severely limited by the hostile characteristics of plants. Arthropods have nonetheless counteracted many nutritional and defensive barriers imposed by plants and are currently considered as the most successful animal herbivores in terrestrial ecosystems. We gather a body of evidence showing that genomes of various plant feeding insects and mites possess genes whose presence can only be explained by horizontal gene transfer (HGT). HGT is the asexual transmission of genetic information between reproductively isolated species. Although HGT is known to have great adaptive significance in prokaryotes, its impact on eukaryotic evolution remains obscure. Here, we show that laterally transferred genes into arthropods underpin many adaptations to phytophagy, including efficient assimilation and detoxification of plant produced metabolites. Horizontally acquired genes and the traits they encode often functionally diversify within arthropod recipients, enabling the colonization of more host plant species and organs. We demonstrate that HGT can drive metazoan evolution by uncovering its prominent role in the adaptations of arthropods to exploit plants. PMID:27307274

  3. EFFECTS OF MICROBIAL PESTICIDES ON NON-TARGET BENEFICIAL ARTHROPODS

    EPA Science Inventory

    The formulation, testing protocol, lethal effects, sub-lethal effects, ecological relationships and selectivity of microbial pesticides on non-target, beneficial arthropod natural enemies of insect and mite pests are reviewed for viruses, bacteria, fungi and protozoa. It was foun...

  4. Bioactivity of cedarwood oil and cedrol against arthropod pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Heartwood samples from Juniperus virginiana, were extracted with liquid carbon dioxide and the bioactivity of carbon dioxide-derived cedarwood oil (CWO) towards several species of arthropods was investigated. Repellency or toxicity was tested for ants, ticks, and cockroaches. Ants in an outdoor bi...

  5. Arthropod Deterrents from Artemisia pallens (Davana Oil) Components.

    PubMed

    Bhagavathy, Ganga V; Velazquez Nieves, Glory M; Webb, Meiling Z; Chauhan, Kamlesh R

    2015-08-01

    Davanone, a key sesquiterpene component of davana oil, has been synthesized in five convenient steps. Oxygenated sesquiterpenes have been linked to insect deterrent properties. Based on initial screening of davana oil, davanone and its hydroxy precursors have been generated and are being evaluated as arthropod deterrents against disease vectors. PMID:26434107

  6. Application of remote sensing to arthropod vector surveillance and control.

    PubMed

    Washino, R K; Wood, B L

    1994-01-01

    A need exists to further develop new technologies, such as remote sensing and geographic information systems analysis, for estimating arthropod vector abundance in aquatic habitats and predicting adult vector population outbreaks. A brief overview of remote sensing technology in vector surveillance and control is presented, and suggestions are made on future research opportunities in light of current and proposed remote sensing systems. PMID:8024079

  7. Arthropod Surveillance Programs: Basic Components, Strategies, and Analysis

    PubMed Central

    Rochon, Kateryn; Duehl, Adrian J.; Anderson, John F.; Barrera, Roberto; Su, Nan-Yao; Gerry, Alec C.; Obenauer, Peter J.; Campbell, James F.; Lysyk, Tim J.; Allan, Sandra A.

    2015-01-01

    Effective entomological surveillance planning stresses a careful consideration of methodology, trapping technologies, and analysis techniques. Herein, the basic principles and technological components of arthropod surveillance plans are described, as promoted in the symposium “Advancements in arthropod monitoring technology, techniques, and analysis” presented at the 58th annual meeting of the Entomological Society of America in San Diego, CA. Interdisciplinary examples of arthropod monitoring for urban, medical, and veterinary applications are reviewed. Arthropod surveillance consists of the three components: 1) sampling method, 2) trap technology, and 3) analysis technique. A sampling method consists of selecting the best device or collection technique for a specific location and sampling at the proper spatial distribution, optimal duration, and frequency to achieve the surveillance objective. Optimized sampling methods are discussed for several mosquito species (Diptera: Culicidae) and ticks (Acari: Ixodidae). The advantages and limitations of novel terrestrial and aerial insect traps, artificial pheromones and kairomones are presented for the capture of red flour beetle (Coleoptera: Tenebrionidae), small hive beetle (Coleoptera: Nitidulidae), bed bugs (Hemiptera: Cimicidae), and Culicoides (Diptera: Ceratopogonidae) respectively. After sampling, extrapolating real world population numbers from trap capture data are possible with the appropriate analysis techniques. Examples of this extrapolation and action thresholds are given for termites (Isoptera: Rhinotermitidae) and red flour beetles. PMID:26543242

  8. Horizontal Gene Transfer Contributes to the Evolution of Arthropod Herbivory.

    PubMed

    Wybouw, Nicky; Pauchet, Yannick; Heckel, David G; Van Leeuwen, Thomas

    2016-01-01

    Within animals, evolutionary transition toward herbivory is severely limited by the hostile characteristics of plants. Arthropods have nonetheless counteracted many nutritional and defensive barriers imposed by plants and are currently considered as the most successful animal herbivores in terrestrial ecosystems. We gather a body of evidence showing that genomes of various plant feeding insects and mites possess genes whose presence can only be explained by horizontal gene transfer (HGT). HGT is the asexual transmission of genetic information between reproductively isolated species. Although HGT is known to have great adaptive significance in prokaryotes, its impact on eukaryotic evolution remains obscure. Here, we show that laterally transferred genes into arthropods underpin many adaptations to phytophagy, including efficient assimilation and detoxification of plant produced metabolites. Horizontally acquired genes and the traits they encode often functionally diversify within arthropod recipients, enabling the colonization of more host plant species and organs. We demonstrate that HGT can drive metazoan evolution by uncovering its prominent role in the adaptations of arthropods to exploit plants. PMID:27307274

  9. Extreme Arthropods: Exploring Evolutionary Adaptations to Polar and Temperate Deserts

    ERIC Educational Resources Information Center

    Sandro, Luke; Constible, Juanita M.; Lee, Richard E., Jr.

    2007-01-01

    In this activity, Namib and Antarctic arthropods are used to illustrate several important biological principles. Among these are the key ideas that form follows function and that the environment drives evolution. In addition, students will discover that the climates of the Namib Desert and the Antarctic Peninsula are similar in several ways, and…

  10. An Approach to Mark Arthropods for Mark Capture Type Research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of studies were conducted to validate methods for marking a wide variety of arthropods with inexpensive proteins for mark-capture dispersal research. The markers tested included egg albumin protein in chicken egg whites and casein protein in bovine milk. The first study qualified the effec...

  11. Soluble proteins of chemical communication: an overview across arthropods

    PubMed Central

    Pelosi, Paolo; Iovinella, Immacolata; Felicioli, Antonio; Dani, Francesca R.

    2014-01-01

    Detection of chemical signals both in insects and in vertebrates is mediated by soluble proteins, highly concentrated in olfactory organs, which bind semiochemicals and activate, with still largely unknown mechanisms, specific chemoreceptors. The same proteins are often found in structures where pheromones are synthesized and released, where they likely perform a second role in solubilizing and delivering chemical messengers in the environment. A single class of soluble polypeptides, called Odorant-Binding Proteins (OBPs) is known in vertebrates, while two have been identified in insects, OBPs and CSPs (Chemosensory Proteins). Despite their common name, OBPs of vertebrates bear no structural similarity with those of insects. We observed that in arthropods OBPs are strictly limited to insects, while a few members of the CSP family have been found in crustacean and other arthropods, where however, based on their very limited numbers, a function in chemical communication seems unlikely. The question we address in this review is whether another class of soluble proteins may have been adopted by other arthropods to perform the role of OBPs and CSPs in insects. We propose that lipid-transporter proteins of the Niemann-Pick type C2 family could represent likely candidates and report the results of an analysis of their sequences in representative species of different arthropods. PMID:25221516

  12. Fungal Taxa Target Different Carbon Substrates in Harvard Forest Soils

    NASA Astrophysics Data System (ADS)

    Hanson, C. A.; Allison, S. D.; Wallenstein, M. D.; Mellilo, J. M.; Treseder, K. K.

    2006-12-01

    The mineralization of soil organic carbon is a major component of the global carbon cycle and is largely controlled by soil microbial communities. However, little is known about the functional roles of soil microbes or whether different microbial taxa target different carbon substrates under natural conditions. To examine this possibility, we assessed the community composition of active fungi by using a novel nucleotide analog technique in soils from the Harvard Forest. We hypothesized that fungal community composition would shift in response to the addition of different substrates and that specific fungal taxa would respond differentially to particular carbon sources. To test this hypothesis, we added a nucleotide analog probe directly to soils in conjunction with one of five carbon compounds of increasing recalcitrance: glycine, sucrose, cellulose, tannin-protein complex, and lignin. During 48 hour incubations, the nucleotide analog was incorporated into newly replicated DNA of soil organisms that proliferated following the addition of the substrates. In this way, we labeled the DNA of microbes that respond to a particular carbon source. Labeled DNA was isolated and fungal Internal Transcribed Spacer (ITS) regions of ribosomal DNA (rDNA) were sequenced and analyzed to identify active fungi to near-species resolution. Diversity analyses at the ≥97% sequence similarity level indicated that taxonomic richness was greater under cellulose (Shannon Index: 3.23 ± 0.11 with ± 95% CI) and lignin (2.87 ± 0.15) additions than the other treatments (2.34 ± 0.16 to 2.64 ± 0.13). In addition, community composition of active fungi shifted under glycine, sucrose, and cellulose additions. Specifically, the community under glycine was significantly different from communities under control, cellulose, and tannin-protein (P<0.05). Additionally, the sucrose and cellulose communities were marginally different from the control community (P = 0.059 and 0.054, respectively) and

  13. Influence of crop management practices on bean foliage arthropods.

    PubMed

    Pereira, J L; Picanço, M C; Pereira, E J G; Silva, A A; Jakelaitis, A; Pereira, R R; Xavier, V M

    2010-12-01

    Crop management practices can affect the population of phytophagous pest species and beneficial arthropods with consequences for integrated pest management. In this study, we determined the effect of no-tillage and crop residue management on the arthropod community associated with the canopy of common beans (Phaseolus vulgaris L.). Abundance and species composition of herbivorous, detritivorous, predaceous and parasitoid arthropods were recorded during the growing seasons of 2003 and 2004 in Coimbra County, Minas Gerais State, Brazil. Arthropod diversity and guild composition were similar among crop management systems, but their abundance was higher under no-tillage relative to conventional cultivation and where residues from the preceding crop were maintained in the field. Thirty-four arthropod species were recorded, and those most representative of the impact of the crop management practices were Hypogastrura springtails, Empoasca kraemeri and Circulifer leafhoppers, and Solenopsis ants. The infestation levels of major insect-pests, especially leafhoppers (Hemiptera: Cicadellidae), was on average seven-fold lower under no-tillage with retention of crop residues relative to the conventional system with removal of residues, whereas the abundance of predatory ants (Hymenoptera: Formicidae) and springtails (Collembola: Hypogastruridae) were, respectively, about seven- and 15-fold higher in that treatment. Importantly, a significant trophic interaction among crop residues, detritivores, predators and herbivores was observed. Plots managed with no-tillage and retention of crop residues had the highest bean yield, while those with conventional cultivation and removal of the crop residues yielded significantly less beans. This research shows that cropping systems that include zero tillage and crop residue retention can reduce infestation by foliar insect-pests and increase abundance of predators and detritivores, thus having direct consequences for insect pest management

  14. Leaf litter arthropod responses to tropical forest restoration.

    PubMed

    Cole, Rebecca J; Holl, Karen D; Zahawi, Rakan A; Wickey, Philipp; Townsend, Alan R

    2016-08-01

    Soil and litter arthropods represent a large proportion of tropical biodiversity and perform important ecosystem functions, but little is known about the efficacy of different tropical forest restoration strategies in facilitating their recovery in degraded habitats. We sampled arthropods in four 7- to 8-year-old restoration treatments and in nearby reference forests. Sampling was conducted during the wet and dry seasons using extractions from litter and pitfall samples. Restoration treatments were replicated in 50 × 50-m plots in four former pasture sites in southern Costa Rica: plantation - trees planted throughout the plot; applied nucleation/islands - trees planted in patches of different sizes; and natural regeneration - no tree planting. Arthropod abundance, measures of richness and diversity, and a number of functional groups were greater in the island treatment than in natural regeneration or plantation treatments and, in many cases, were similar to reference forest. Litter and pitfall morphospecies and functional group composition in all three restoration treatments were significantly different than reference sites, but island and plantation treatments showed more recovery than natural regeneration. Abundance and functional group diversity showed a much greater degree of recovery than community composition. Synthesis and applications: The less resource-intensive restoration strategy of planting tree islands was more effective than tree plantations in restoring arthropod abundance, richness, and functional diversity. None of the restoration strategies, however, resulted in similar community composition as reference forest after 8 years of recovery, highlighting the slow rate of recovery of arthropod communities after disturbance, and underscoring the importance of conservation of remnant forests in fragmented landscapes. PMID:27551373

  15. Earliest Carboniferous tetrapod and arthropod faunas from Scotland populate Romer's Gap

    PubMed Central

    Smithson, Timothy R.; Wood, Stanley P.; Marshall, John E. A.; Clack, Jennifer A.

    2012-01-01

    Devonian tetrapods (limbed vertebrates), known from an increasingly large number of localities, have been shown to be mainly aquatic with many primitive features. In contrast, the post-Devonian record is marked by an Early Mississippian temporal gap ranging from the earliest Carboniferous (Tournaisian and early Viséan) to the mid-Viséan. By the mid-Viséan, tetrapods had become effectively terrestrial as attested by the presence of stem amniotes, developed an essentially modern aspect, and given rise to the crown group. Up to now, only two localities have yielded tetrapod specimens from the Tournaisian stage: one in Scotland with a single articulated skeleton and one in Nova Scotia with isolated bones, many of uncertain identity. We announce a series of discoveries of Tournaisian-age localities in Scotland that have yielded a wealth of new tetrapod and arthropod fossils. These include both terrestrial and aquatic forms and new taxa. We conclude that the gap in the fossil record has been an artifact of collection failure. PMID:22393016

  16. Land use intensification effects in soil arthropod community of an entisol in Pernambuco State, Brazil.

    PubMed

    Siqueira, G M; Silva, E F F; Paz-Ferreiro, J

    2014-01-01

    The interactions between soil invertebrates and land use and management are fundamental for soil quality assessment but remain largely unaddressed. The aim of this study was to evaluate the changes in soil arthropod community of an entisol brought about by different land use systems under semiarid climate in Pernambuco State, Brazil. The soil invertebrate community was sampled using pitfall traps from areas with eight vegetation types by the end of the austral winter. The land uses studied were native thorn forest plus seven agricultural fields planted with elephant grass, apple guava, passion fruit, carrot, maize, tomato, and green pepper. Native vegetation was considered as a reference, whereas the agricultural fields showed a range of soil use intensities. The abundance of organisms, the total and average richness, Shannon's diversity index, and the Pielou uniformity index were determined, and all of these were affected by several crop and soil management practices such as residue cover, weed control, and pesticide application. Our study found differences in community assemblages and composition under different land use systems, but no single taxa could be used as indicator of soil use intensity. PMID:25431792

  17. Impact of Grassland Reseeding, Herbicide Spraying and Ploughing on Diversity and Abundance of Soil Arthropods.

    PubMed

    Liu, Wei; Zhang, Junling; Norris, Stuart L; Murray, Philip J

    2016-01-01

    In order to determine the interactive effect of reseeding, herbicide spraying and ploughing on soil fauna communities, we conducted a grassland reseeding experiment combined with pre-reseed management to examine how with the whole reseeding process affects soil faunal composition. Sampling occasions and exact treatments were as follows: (1) before chemical herbicide spray; (2) after spray but before ploughing; (3) after ploughing but before reseeding; and (4) after 1 year of recovery. Our results demonstrate that, Acari and Collembola were the two soil fauna taxa with the highest abundance and accounted for around 96% of the relative total abundance among the various managements. Herbicide application tended to increase soil invertebrate abundance. Conversely, subsequent ploughing significantly reduced soil invertebrate abundance and had an obvious negative effect on soil primary and secondary decomposers, which were mainly due to the variations of Acari (especially Oribatida) and Coleoptera group abundance. Moreover, reseeding also reduced the individual number of the groups mentioned above, and favored those predators with a larger body size and individual weight. After 1 year recovery, Collembola abundance recovered to the pre-treatment levels, while with Arthropod and Acari groups were still fluctuating. PMID:27555863

  18. Earliest Carboniferous tetrapod and arthropod faunas from Scotland populate Romer's Gap

    NASA Astrophysics Data System (ADS)

    Smithson, Timothy R.; Wood, Stanley P.; Marshall, John E. A.; Clack, Jennifer A.

    2012-03-01

    Devonian tetrapods (limbed vertebrates), known from an increasingly large number of localities, have been shown to be mainly aquatic with many primitive features. In contrast, the post-Devonian record is marked by an Early Mississippian temporal gap ranging from the earliest Carboniferous (Tournaisian and early Viséan) to the mid-Viséan. By the mid-Viséan, tetrapods had become effectively terrestrial as attested by the presence of stem amniotes, developed an essentially modern aspect, and given rise to the crown group. Up to now, only two localities have yielded tetrapod specimens from the Tournaisian stage: one in Scotland with a single articulated skeleton and one in Nova Scotia with isolated bones, many of uncertain identity. We announce a series of discoveries of Tournaisian-age localities in Scotland that have yielded a wealth of new tetrapod and arthropod fossils. These include both terrestrial and aquatic forms and new taxa. We conclude that the gap in the fossil record has been an artifact of collection failure.

  19. Land Use Intensification Effects in Soil Arthropod Community of an Entisol in Pernambuco State, Brazil

    PubMed Central

    Siqueira, G. M.; Silva, E. F. F.; Paz-Ferreiro, J.

    2014-01-01

    The interactions between soil invertebrates and land use and management are fundamental for soil quality assessment but remain largely unaddressed. The aim of this study was to evaluate the changes in soil arthropod community of an entisol brought about by different land use systems under semiarid climate in Pernambuco State, Brazil. The soil invertebrate community was sampled using pitfall traps from areas with eight vegetation types by the end of the austral winter. The land uses studied were native thorn forest plus seven agricultural fields planted with elephant grass, apple guava, passion fruit, carrot, maize, tomato, and green pepper. Native vegetation was considered as a reference, whereas the agricultural fields showed a range of soil use intensities. The abundance of organisms, the total and average richness, Shannon's diversity index, and the Pielou uniformity index were determined, and all of these were affected by several crop and soil management practices such as residue cover, weed control, and pesticide application. Our study found differences in community assemblages and composition under different land use systems, but no single taxa could be used as indicator of soil use intensity. PMID:25431792

  20. Impact of Grassland Reseeding, Herbicide Spraying and Ploughing on Diversity and Abundance of Soil Arthropods

    PubMed Central

    Liu, Wei; Zhang, Junling; Norris, Stuart L.; Murray, Philip J.

    2016-01-01

    In order to determine the interactive effect of reseeding, herbicide spraying and ploughing on soil fauna communities, we conducted a grassland reseeding experiment combined with pre-reseed management to examine how with the whole reseeding process affects soil faunal composition. Sampling occasions and exact treatments were as follows: (1) before chemical herbicide spray; (2) after spray but before ploughing; (3) after ploughing but before reseeding; and (4) after 1 year of recovery. Our results demonstrate that, Acari and Collembola were the two soil fauna taxa with the highest abundance and accounted for around 96% of the relative total abundance among the various managements. Herbicide application tended to increase soil invertebrate abundance. Conversely, subsequent ploughing significantly reduced soil invertebrate abundance and had an obvious negative effect on soil primary and secondary decomposers, which were mainly due to the variations of Acari (especially Oribatida) and Coleoptera group abundance. Moreover, reseeding also reduced the individual number of the groups mentioned above, and favored those predators with a larger body size and individual weight. After 1 year recovery, Collembola abundance recovered to the pre-treatment levels, while with Arthropod and Acari groups were still fluctuating. PMID:27555863

  1. 76 FR 20558 - Endangered and Threatened Wildlife and Plants; 44 Marine and Anadromous Taxa: Adding 10 Taxa...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-13

    ...We, the U.S. Fish and Wildlife Service (Service), are amending the List of Endangered and Threatened Wildlife (List) by adding 10 marine taxa, delisting 1 marine taxon, reclassifying 1 marine taxon, and revising 32 marine taxa in accordance with the Endangered Species Act of 1973, as amended (Act). These amendments are based on previously published determinations by the National Marine......

  2. Invertebrate responses to the management of genetically modified herbicide-tolerant and conventional spring crops. II. Within-field epigeal and aerial arthropods.

    PubMed Central

    Haughton, A J; Champion, G T; Hawes, C; Heard, M S; Brooks, D R; Bohan, D A; Clark, S J; Dewar, A M; Firbank, L G; Osborne, J L; Perry, J N; Rothery, P; Roy, D B; Scott, R J; Woiwod, I P; Birchall, C; Skellern, M P; Walker, J H; Baker, P; Browne, E L; Dewar, A J G; Garner, B H; Haylock, L A; Horne, S L; Mason, N S; Sands, R J N; Walker, M J

    2003-01-01

    The effects of the management of genetically modified herbicide-tolerant (GMHT) crops on the abundances of aerial and epigeal arthropods were assessed in 66 beet, 68 maize and 67 spring oilseed rape sites as part of the Farm Scale Evaluations of GMHT crops. Most higher taxa were insensitive to differences between GMHT and conventional weed management, but significant effects were found on the abundance of at least one group within each taxon studied. Numbers of butterflies in beet and spring oilseed rape and of Heteroptera and bees in beet were smaller under the relevant GMHT crop management, whereas the abundance of Collembola was consistently greater in all GMHT crops. Generally, these effects were specific to each crop type, reflected the phenology and ecology of the arthropod taxa, were indirect and related to herbicide management. These results apply generally to agriculture across Britain, and could be used in mathematical models to predict the possible long-term effects of the widespread adoption of GMHT technology. The results for bees and butterflies relate to foraging preferences and might or might not translate into effects on population densities, depending on whether adoption leads to forage reductions over large areas. These species, and the detritivore Collembola, may be useful indicator species for future studies of GMHT management. PMID:14561319

  3. Invertebrate responses to the management of genetically modified herbicide-tolerant and conventional spring crops. II. Within-field epigeal and aerial arthropods.

    PubMed

    Haughton, A J; Champion, G T; Hawes, C; Heard, M S; Brooks, D R; Bohan, D A; Clark, S J; Dewar, A M; Firbank, L G; Osborne, J L; Perry, J N; Rothery, P; Roy, D B; Scott, R J; Woiwod, I P; Birchall, C; Skellern, M P; Walker, J H; Baker, P; Browne, E L; Dewar, A J G; Garner, B H; Haylock, L A; Horne, S L; Mason, N S; Sands, R J N; Walker, M J

    2003-11-29

    The effects of the management of genetically modified herbicide-tolerant (GMHT) crops on the abundances of aerial and epigeal arthropods were assessed in 66 beet, 68 maize and 67 spring oilseed rape sites as part of the Farm Scale Evaluations of GMHT crops. Most higher taxa were insensitive to differences between GMHT and conventional weed management, but significant effects were found on the abundance of at least one group within each taxon studied. Numbers of butterflies in beet and spring oilseed rape and of Heteroptera and bees in beet were smaller under the relevant GMHT crop management, whereas the abundance of Collembola was consistently greater in all GMHT crops. Generally, these effects were specific to each crop type, reflected the phenology and ecology of the arthropod taxa, were indirect and related to herbicide management. These results apply generally to agriculture across Britain, and could be used in mathematical models to predict the possible long-term effects of the widespread adoption of GMHT technology. The results for bees and butterflies relate to foraging preferences and might or might not translate into effects on population densities, depending on whether adoption leads to forage reductions over large areas. These species, and the detritivore Collembola, may be useful indicator species for future studies of GMHT management. PMID:14561319

  4. N-P Co-Limitation of Primary Production and Response of Arthropods to N and P in Early Primary Succession on Mount St. Helens Volcano

    PubMed Central

    Bishop, John G.; O'Hara, Niamh B.; Titus, Jonathan H.; Apple, Jennifer L.; Gill, Richard A.; Wynn, Louise

    2010-01-01

    Background The effect of low nutrient availability on plant-consumer interactions during early succession is poorly understood. The low productivity and complexity of primary successional communities are expected to limit diversity and abundance of arthropods, but few studies have examined arthropod responses to enhanced nutrient supply in this context. We investigated the effects of nitrogen (N) and phosphorus (P) addition on plant productivity and arthropod abundance on 24-yr-old soils at Mount St. Helens volcano. Methodology/Principal Findings We measured the relative abundance of eight arthropod orders and five families in plots that received N, P, or no nutrients for 3–5 years. We also measured plant % cover, leaf %N, and plant diversity. Vegetation responded rapidly to N addition but showed a lagged response to P that, combined with evidence of increased N fixation, suggested P-limitation to N availability. After 3 yrs of fertilization, orthopterans (primarily Anabrus simplex (Tettigoniidae) and Melanoplus spp (Acrididae)) showed a striking attraction to P addition plots, while no other taxa responded to fertilization. After 5 yrs of fertilization, orthopteran density in the same plots increased 80%–130% with P addition and 40% with N. Using structural equation modeling, we show that in year 3 orthopteran abundance was associated with a P-mediated increase in plant cover (or correlated increases in resource quality), whereas in year 5 orthopteran density was not related to cover, diversity or plant %N, but rather to unmeasured effects of P, such as its influence on other aspects of resource quality. Conclusions/Significance The marked surprising response to P by orthopterans, combined with a previous observation of P-limitation in lepidopteran herbivores at these sites, suggests that P-mediated effects of food quantity or quality are critical to insect herbivores in this N-P co-limited primary successional system. Our results also support a previous

  5. Ecology and management of arthropod pests of poultry.

    PubMed

    Axtell, R C; Arends, J J

    1990-01-01

    The worldwide spread of modern, high-density confined poultry production systems under the direction of integrators has intensified the importance of a select number of arthropod ectoparasites and habitat pests. This concentrated production of poultry provides artificial ecosystems that are sometimes ideal for the development of large populations of arthropod pests. At the same time the systems are amenable to integrated pest management involving a multipest and multimethod approach to reducing or eliminating arthropod pests. Since rodents are major pests, they should be included in an integrated pest management program to make the program most cost-effective and attractive to the integrators and producers (5). Quantitative data are scarce on economic effects, and the concept of economic thresholds is difficult to apply either to ectoparasites or to habitat pests. The risk of transporting ectoparasites among flocks is difficult to evaluate and necessitates treatment after early detection of the arthropods. Flies and litter beetles present a threat of disease transmission and the potential for lawsuits from neighbors or public health agencies that are factors not subject to easy cost estimates. The monetary losses of a flock devastated by disease or a farm forced to close are so great that the risks are unacceptable. Production losses from lowered feed conversion ratios and insulation damage are likely to be detected by the sophisticated record-keeping of the integrators. Minimal use of pesticides and other chemicals on poultry and in poultry housing is an objective of the integrators and, consequently, an integrated pest management (IPM) approach that reduces the need for pesticides is attractive. The key to further development of effective arthropod management programs for poultry is the implementation of pest and disease monitoring programs for the complete system. Improvements in arthropod sampling methods and more attention to monitoring the biosecurity systems

  6. Higher thermal acclimation potential of respiration but not photosynthesis in two alpine Picea taxa in contrast to two lowland congeners.

    PubMed

    Zhang, Xiao Wei; Wang, Jing Ru; Ji, Ming Fei; Milne, Richard Ian; Wang, Ming Hao; Liu, Jian-Quan; Shi, Sheng; Yang, Shu-Li; Zhao, Chang-Ming

    2015-01-01

    The members of the genus Picea form a dominant component in many alpine and boreal forests which are the major sink for atmospheric CO2. However, little is known about the growth response and acclimation of CO2 exchange characteristics to high temperature stress in Picea taxa from different altitudes. Gas exchange parameters and growth characteristics were recorded from four year old seedlings of two alpine (Picea likiangensis vars. rubescens and linzhiensis) and two lowland (P. koraiensis and P. meyeri) taxa. Seedlings were grown at moderate (25°C/15°C) and high (35°C/25°C) day/night temperatures, for four months. The approximated biomass increment (ΔD2H) for all taxa decreased under high temperature stress, associated with decreased photosynthesis and increased respiration. However, the two alpine taxa exhibited lower photosynthetic acclimation and higher respiratory acclimation than either lowland taxon. Moreover, higher leaf dry mass per unit area (LMA) and leaf nitrogen content per unit area (Narea), and a smaller change in the nitrogen use efficiency of photosynthesis (PNUE) for lowland taxa indicated that these maintained higher homeostasis of photosynthesis than alpine taxa. The higher respiration rates produced more energy for repair and maintenance biomass, especially for higher photosynthetic activity for lowland taxa, which causes lower respiratory acclimation. Thus, the changes of ΔD2H for alpine spruces were larger than that for lowland spruces. These results indicate that long term heat stress negatively impact on the growth of Picea seedlings, and alpine taxa are more affected than low altitude ones by high temperature stress. Hence the altitude ranges of Picea taxa should be taken into account when predicting changes to carbon fluxes in warmer conditions. PMID:25874631

  7. Short-Term Protein Stable Isotope Probing of Microbial Communities to Associate Functions with Taxa (Invited)

    NASA Astrophysics Data System (ADS)

    Lipton, M. S.; Slysz, G. W.; Steinke, L. A.; Ward, D. M.; Klatt, C. G.; Clauss, T. R.; Purvine, S. O.; Anderson, G. A.; Payne, S. H.; Bryant, D. A.

    2013-12-01

    Determining which taxa in a community perform which functions is essential for understanding metabolite fluxes and metabolic interactions among community members. Specific taxa will alter their metabolism in order to acclimate to changing environmental factors such as light through the diel cycle, changing temperature and other factors. Monitoring which proteins are being expressed, and the quantitative protein expression patterns in the individual taxa as a response to external stimuli is key to understanding these mechanisms. Protein stable isotope probing (Pro-SIP) has strong potential for revealing key metabolizing taxa in complex microbial communities. In Pro-SIP studies, label incorporation is determined by the extent of the change in the isotopic profile of peptides when measured by mass spectrometry. While most Pro-SIP work to date has been performed under controlled laboratory conditions to allow extensive isotope labeling of the target organism(s), these techniques have not been applied to short term in situ studies due to the small degree of partial labeling of the proteins. We have applied Pro-SIP to study the assimilation of a labeled substrate into proteins to determine which taxa are responsible for sequestration of dissolved inorganic carbon in microbial mats associated with the alkaline siliceous hot springs of Yellowstone National Park. This community is fueled by sunlight as it transitions from dark to light; the aim was to understand the light-dependent pathway of inorganic carbon incorporation into different taxa during the early morning hours when the mat was in low light and anoxic. Each mat sample was incubated with 13C-bicarbonate for 3 h. Substrate assimilation was determined through standard proteomic techniques along with the use of SIPPER, a collection of algorithms that sensitively measure small changes in peptide isotopic patterns, allowing the determination of which taxa assimilated the substrate during this period. For the

  8. Symbiont acquisition as neoseme: origin of species and higher taxa

    NASA Technical Reports Server (NTRS)

    Bermudes, D.; Margulis, L.

    1987-01-01

    We examine the hypothesis that, in the origin of species and higher taxa of eukaryotes, symbiont acquisition followed by partner integration has been equivalent to neoseme appearance leading to speciation. The formation of stable symbiotic associations involves partner-surface recognition, behavioral and metabolic interaction, and, in some cases, gene product (RNA, protein) and genic (RNA, DNA) integration. This analysis is applied here to examples of neosemes that define specific taxa and to neosemes in plants, fungi, and animals that involve the appearance of new types of tissue. If this hypothesis is correct--if the origin of major genetic variation leading to speciation and even higher taxa may occur through symbiont acquisition and integration--then the analysis of "origins of species and higher taxa" becomes analogous to the study of microbial community ecology.

  9. Instantaneous threat escape and differentiated refuge demand among zooplankton taxa.

    PubMed

    Hansson, Lars-Anders; Bianco, Giuseppe; Ekvall, Mikael; Heuschele, Jan; Hylander, Samuel; Yang, Xi

    2016-02-01

    Most animals, including aquatic crustacean zooplankton, perform strong avoidance movements when exposed to a threat, such as ultraviolet radiation (UVR). We here show that the genera Daphnia and Bosmina instantly adjust their vertical position in the water in accordance with the present UVR threat, i.e., seek refuge in deeper waters, whereas other taxa show less response to the threat. Moreover, Daphnia repeatedly respond to UVR pulses, suggesting that they spend more energy on movement than more stationary taxa, for example, during days with fluctuating cloud cover, illustrating nonlethal effects in avoiding UVR threat. Accordingly, we also show that the taxa with the most contrasting behavioral responses differ considerably in photoprotection, suggesting different morphological and behavioral strategies in handling the UVR threat. In a broader context, our studies on individual and taxa specific responses to UVR provide insights into observed spatial and temporal distribution in natural ecosystems. PMID:27145603

  10. Survey of the arthropods on jojoba (Simmondsia chinensis)

    SciTech Connect

    Pinto, J.D.; Frommer, S.I.

    1980-02-01

    Simmondsia chinensis (jojoba), a plant native to southwestern North America, has become of economic interest due to the various industrial uses of the unique liquid wax found in its seeds. In a survey of arthropods associated with sylvatic jojoba in California and Arizona, we collected 106 species of insects and mites. Of these, 50 are phytophagous, 29 are parasitic, and 18 are predaceous. Most of the phytophagous species are also known to feed on plants other than jojoba; several of these are notorious generalists. The bionomics of the 4 commonest phytophagous species, Asphondylia n. sp. (Cecidomyiidae), Epinotia kasloana (Olethreutidae), Periploca n. sp. (Walshiidae), and Incisitermes fruticavus (Kalotermitidae) are summarized briefly. None of the phytophagous species were observed to cause extensive damage to sylvatic jojoba. The numerous parasitic and predaceous arthropods probably account for the natural control of many of them. These relationships should be kept in mind when planning future commercial plantations of jojoba.

  11. Personal Protection Measures Against Mosquitoes, Ticks, and Other Arthropods.

    PubMed

    Alpern, Jonathan D; Dunlop, Stephen J; Dolan, Benjamin J; Stauffer, William M; Boulware, David R

    2016-03-01

    Arthropod-associated diseases are a major cause of morbidity among travelers. Obtaining a detailed travel itinerary and understanding traveler-specific and destination-specific risk factors can help mitigate the risk of vector-borne diseases. DEET, picaridin, PMD, and IR3535 are insect repellents that offer sufficient protection against arthropod bites. IR3535 does not provide adequate protection against Anopheles mosquitoes, and should be avoided in malaria-endemic regions. General protective measures, such as bite avoidance, protective clothing, insecticide-treated bed nets, and insecticide-treated clothing, should be recommended, especially in malaria-endemic areas. Spatial repellents may prevent nuisance biting, but have not been shown to prevent against vector-borne disease. PMID:26900115

  12. Arthropod venom Hyaluronidases: biochemical properties and potential applications in medicine and biotechnology.

    PubMed

    Bordon, Karla C F; Wiezel, Gisele A; Amorim, Fernanda G; Arantes, Eliane C

    2015-01-01

    Hyaluronidases are enzymes that mainly degrade hyaluronan, the major glycosaminoglycan of the interstitial matrix. They are involved in several pathological and physiological activities including fertilization, wound healing, embryogenesis, angiogenesis, diffusion of toxins and drugs, metastasis, pneumonia, sepsis, bacteremia, meningitis, inflammation and allergy, among others. Hyaluronidases are widely distributed in nature and the enzymes from mammalian spermatozoa, lysosomes and animal venoms belong to the subclass EC 3.2.1.35. To date, only five three-dimensional structures for arthropod venom hyaluronidases (Apis mellifera and Vespula vulgaris) were determined. Additionally, there are four molecular models for hyaluronidases from Mesobuthus martensii, Polybia paulista and Tityus serrulatus venoms. These enzymes are employed as adjuvants to increase the absorption and dispersion of other drugs and have been used in various off-label clinical conditions to reduce tissue edema. Moreover, a PEGylated form of a recombinant human hyaluronidase is currently under clinical trials for the treatment of metastatic pancreatic cancer. This review focuses on the arthropod venom hyaluronidases and provides an overview of their biochemical properties, role in the envenoming, structure/activity relationship, and potential medical and biotechnological applications. PMID:26500679

  13. Arthropod model systems for studying complex biological processes in the space environment

    NASA Astrophysics Data System (ADS)

    Marco, Roberto; de Juan, Emilio; Ushakov, Ilya; Hernandorena, Arantxa; Gonzalez-Jurado, Juan; Calleja, Manuel; Manzanares, Miguel; Maroto, Miguel; Garesse, Rafael; Reitz, Günther; Miquel, Jaime

    1994-08-01

    Three arthropod systems are discussed in relation to their complementary and potential use in Space Biology. In a next biosatellite flight, Drosophila melanogaster pre-adapted during several months to different g levels will be flown in an automatic device that separates parental from first and second generations. In the same flight, flies will be exposed to microgravity conditions in an automatic unit in which fly motility can be recorded. In the International Microgravity Laboratory-2, several groups of Drosophila embryos will be grown in Space and the motility of a male fly population will be video-recorded. In the Biopan, an ESA exobilogy facility that can be flown attached to the exterior of a Russian biosatellite, Artemia dormant gastrulae will be exposed to the space environment in the exterior of the satellite under a normal atmosphere or in the void. Gastrulae will be separated in hit and non-hit populations. The developmental and aging response of these animals will be studied upon recovery. With these experiments we will be able to establish whether exposure to the space environment influences arthropod development and aging, and elaborate on some of the cellular mechanisms involved which should be tested in future experiments.

  14. Cyberdiversity: Improving the Informatic Value of Diverse Tropical Arthropod Inventories

    PubMed Central

    Miller, Jeremy A.; Miller, Joshua H.; Pham, Dinh-Sac; Beentjes, Kevin K.

    2014-01-01

    In an era of biodiversity crisis, arthropods have great potential to inform conservation assessment and test hypotheses about community assembly. This is because their relatively narrow geographic distributions and high diversity offer high-resolution data on landscape-scale patterns of biodiversity. However, a major impediment to the more widespread application of arthropod data to a range of scientific and policy questions is the poor state of modern arthropod taxonomy, especially in the tropics. Inventories of spiders and other megadiverse arthropods from tropical forests are dominated by undescribed species. Such studies typically organize their data using morphospecies codes, which make it difficult for data from independent inventories to be compared and combined. To combat this shortcoming, we offer cyberdiversity, an online community-based approach for reconciling results of independent inventory studies where current taxonomic knowledge is incomplete. Participating scientists can upload images and DNA barcode sequences to dedicated databases and submit occurrence data and links to a web site (www.digitalSpiders.org). Taxonomic determinations can be shared with a crowdsourcing comments feature, and researchers can discover specimens of interest available for loan and request aliquots of genomic DNA extract. To demonstrate the value of the cyberdiversity framework, we reconcile data from three rapid structured inventories of spiders conducted in Vietnam with an independent inventory (Doi Inthanon, Thailand) using online image libraries. Species richness and inventory completeness were assessed using non-parametric estimators. Community similarity was evaluated using a novel index based on the Jaccard replacing observed with estimated values to correct for unobserved species. We use a distance-decay framework to demonstrate a rudimentary model of landscape-scale changes in community composition that will become increasingly informative as additional

  15. Cyberdiversity: improving the informatic value of diverse tropical arthropod inventories.

    PubMed

    Miller, Jeremy A; Miller, Joshua H; Pham, Dinh-Sac; Beentjes, Kevin K

    2014-01-01

    In an era of biodiversity crisis, arthropods have great potential to inform conservation assessment and test hypotheses about community assembly. This is because their relatively narrow geographic distributions and high diversity offer high-resolution data on landscape-scale patterns of biodiversity. However, a major impediment to the more widespread application of arthropod data to a range of scientific and policy questions is the poor state of modern arthropod taxonomy, especially in the tropics. Inventories of spiders and other megadiverse arthropods from tropical forests are dominated by undescribed species. Such studies typically organize their data using morphospecies codes, which make it difficult for data from independent inventories to be compared and combined. To combat this shortcoming, we offer cyberdiversity, an online community-based approach for reconciling results of independent inventory studies where current taxonomic knowledge is incomplete. Participating scientists can upload images and DNA barcode sequences to dedicated databases and submit occurrence data and links to a web site (www.digitalSpiders.org). Taxonomic determinations can be shared with a crowdsourcing comments feature, and researchers can discover specimens of interest available for loan and request aliquots of genomic DNA extract. To demonstrate the value of the cyberdiversity framework, we reconcile data from three rapid structured inventories of spiders conducted in Vietnam with an independent inventory (Doi Inthanon, Thailand) using online image libraries. Species richness and inventory completeness were assessed using non-parametric estimators. Community similarity was evaluated using a novel index based on the Jaccard replacing observed with estimated values to correct for unobserved species. We use a distance-decay framework to demonstrate a rudimentary model of landscape-scale changes in community composition that will become increasingly informative as additional

  16. Mechanisms of Arthropod Transmission of Plant and Animal Viruses

    PubMed Central

    Gray, Stewart M.; Banerjee, Nanditta

    1999-01-01

    A majority of the plant-infecting viruses and many of the animal-infecting viruses are dependent upon arthropod vectors for transmission between hosts and/or as alternative hosts. The viruses have evolved specific associations with their vectors, and we are beginning to understand the underlying mechanisms that regulate the virus transmission process. A majority of plant viruses are carried on the cuticle lining of a vector’s mouthparts or foregut. This initially appeared to be simple mechanical contamination, but it is now known to be a biologically complex interaction between specific virus proteins and as yet unidentified vector cuticle-associated compounds. Numerous other plant viruses and the majority of animal viruses are carried within the body of the vector. These viruses have evolved specific mechanisms to enable them to be transported through multiple tissues and to evade vector defenses. In response, vector species have evolved so that not all individuals within a species are susceptible to virus infection or can serve as a competent vector. Not only are the virus components of the transmission process being identified, but also the genetic and physiological components of the vectors which determine their ability to be used successfully by the virus are being elucidated. The mechanisms of arthropod-virus associations are many and complex, but common themes are beginning to emerge which may allow the development of novel strategies to ultimately control epidemics caused by arthropod-borne viruses. PMID:10066833

  17. Genetic diversity in aspen and its relation to arthropod abundance

    PubMed Central

    Zhang, Chunxia; Vornam, Barbara; Volmer, Katharina; Prinz, Kathleen; Kleemann, Frauke; Köhler, Lars; Polle, Andrea; Finkeldey, Reiner

    2015-01-01

    The ecological consequences of biodiversity have become a prominent public issue. Little is known on the effect of genetic diversity on ecosystem services. Here, a diversity experiment was established with European and North American aspen (Populus tremula, P. tremuloides) planted in plots representing either a single deme only or combinations of two, four and eight demes. The goals of this study were to explore the complex inter- and intraspecific genetic diversity of aspen and to then relate three measures for diversity (deme diversity, genetic diversity determined as Shannon index or as expected heterozygosity) to arthropod abundance. Microsatellite and AFLP markers were used to analyze the genetic variation patterns within and between the aspen demes and deme mixtures. Large differences were observed regarding the genetic diversity within demes. An analysis of molecular variance revealed that most of the total genetic diversity was found within demes, but the genetic differentiation among demes was also high. The complex patterns of genetic diversity and differentiation resulted in large differences of the genetic variation within plots. The average diversity increased from plots with only one deme to plots with two, four, and eight demes, respectively and separated plots with and without American aspen. To test whether intra- and interspecific diversity impacts on ecosystem services, arthropod abundance was determined. Increasing genetic diversity of aspen was related to increasing abundance of arthropods. However, the relationship was mainly driven by the presence of American aspen suggesting that species identity overrode the effect of intraspecific variation of European aspen. PMID:25674097

  18. [Arthropods with vectorial interest in spanish public health].

    PubMed

    Bueno Marí, Rubén; Moreno Marí, Josefa; Oltra Moscardó, M Teresa; Jiménez Peydró, Ricardo

    2009-01-01

    Fifteen of the thirty-one Obligatory Communicable Diseases in Spain, exempting those of congenital or neonatal types, can be transmitted by several species of arthropods that are present in our country. Several arthropod orders are the suitable transmitters of tens of bacteria, fungi, virus and protozoa. This fact demands a through of the biology knowledge of these vectors in order to adopt efficient control measures that allow us to reduce the incidence levels of these diseases. Nevertheless, the epidemiological studies shouldn't remain only restricted to the diseases with active transmission cycles in our country. It is necessary to acquire a global vision because of allochton diseases that are perfectly extensible to our territory in the globalization context in which we are situated. All this information is important to know which factors are preventing the disease presence. The aim is to provide the National Epidemiological Surveillance Network with a valuable predictive capacity that allows it to predict the potential arrival of diseases and the consequent strengthening of the spanish Public Health. The goal of this work is to carry out a review of the spanish arthropod fauna with any vectorial interest. The current situation of some of the more important vectorial diseases in our country and the factors related to a resurgence reappearance and/or intensification of those ones are also discussed. Therefore, the study of these inappealable protagonists in our Public Health as an articulatory element in the complex network that any vectorial disease entails is absolutely necessary. PMID:19626248

  19. Digital cameras with designs inspired by the arthropod eye.

    PubMed

    Song, Young Min; Xie, Yizhu; Malyarchuk, Viktor; Xiao, Jianliang; Jung, Inhwa; Choi, Ki-Joong; Liu, Zhuangjian; Park, Hyunsung; Lu, Chaofeng; Kim, Rak-Hwan; Li, Rui; Crozier, Kenneth B; Huang, Yonggang; Rogers, John A

    2013-05-01

    In arthropods, evolution has created a remarkably sophisticated class of imaging systems, with a wide-angle field of view, low aberrations, high acuity to motion and an infinite depth of field. A challenge in building digital cameras with the hemispherical, compound apposition layouts of arthropod eyes is that essential design requirements cannot be met with existing planar sensor technologies or conventional optics. Here we present materials, mechanics and integration schemes that afford scalable pathways to working, arthropod-inspired cameras with nearly full hemispherical shapes (about 160 degrees). Their surfaces are densely populated by imaging elements (artificial ommatidia), which are comparable in number (180) to those of the eyes of fire ants (Solenopsis fugax) and bark beetles (Hylastes nigrinus). The devices combine elastomeric compound optical elements with deformable arrays of thin silicon photodetectors into integrated sheets that can be elastically transformed from the planar geometries in which they are fabricated to hemispherical shapes for integration into apposition cameras. Our imaging results and quantitative ray-tracing-based simulations illustrate key features of operation. These general strategies seem to be applicable to other compound eye devices, such as those inspired by moths and lacewings (refracting superposition eyes), lobster and shrimp (reflecting superposition eyes), and houseflies (neural superposition eyes). PMID:23636401

  20. Structural Diversity of Self-Assembled Iridescent Arthropod Biophotonic Nanostructures

    NASA Astrophysics Data System (ADS)

    Saranathan, Vinod Kumar; Prum, Richard O.

    2015-03-01

    Many organisms, especially arthropods, produce vivid interference colors using diverse mesoscopic (100-350 nm) integumentary biophotonic nanostructures that are increasingly being investigated for technological applications. Despite a century of interest, we lack precise structural knowledge of many biophotonic nanostructures and mechanisms controlling their development, when such knowledge can open novel biomimetic routes to facilely self-assemble tunable, multi-functional materials. Here, we use synchrotron small angle X-ray scattering and electron microscopy to characterize the photonic nanostructure of 140 iridescent integumentary scales and setae from 127 species of terrestrial arthropods in 85 genera from 5 orders. We report a rich nanostructural diversity, including triply-periodic bicontinuous networks, close-packed spheres, inverse columnar, perforated lamellar, and disordered sponge-like morphologies, commonly observed as stable phases of amphiphilic surfactants, block copolymer, and lyotropic lipid-water systems. Diverse arthropod lineages appear to have independently evolved to utilize the self-assembly of infolding bilayer membranes to develop biophotonic nanostructures that span the phase-space of amphiphilic morphologies, but at optical length scales.

  1. Trait-based diversification shifts reflect differential extinction among fossil taxa

    PubMed Central

    Wagner, Peter J.; Estabrook, George F.

    2014-01-01

    Evolution provides many cases of apparent shifts in diversification associated with particular anatomical traits. Three general models connect these patterns to anatomical evolution: (i) elevated net extinction of taxa bearing particular traits, (ii) elevated net speciation of taxa bearing particular traits, and (iii) elevated evolvability expanding the range of anatomies available to some species. Trait-based diversification shifts predict elevated hierarchical stratigraphic compatibility (i.e., primitive→derived→highly derived sequences) among pairs of anatomical characters. The three specific models further predict (i) early loss of diversity for taxa retaining primitive conditions (elevated net extinction), (ii) increased diversification among later members of a clade (elevated net speciation), and (iii) increased disparity among later members in a clade (elevated evolvability). Analyses of 319 anatomical and stratigraphic datasets for fossil species and genera show that hierarchical stratigraphic compatibility exceeds the expectations of trait-independent diversification in the vast majority of cases, which was expected if trait-dependent diversification shifts are common. Excess hierarchical stratigraphic compatibility correlates with early loss of diversity for groups retaining primitive conditions rather than delayed bursts of diversity or disparity across entire clades. Cambrian clades (predominantly trilobites) alone fit null expectations well. However, it is not clear whether evolution was unusual among Cambrian taxa or only early trilobites. At least among post-Cambrian taxa, these results implicate models, such as competition and extinction selectivity/resistance, as major drivers of trait-based diversification shifts at the species and genus levels while contradicting the predictions of elevated net speciation and elevated evolvability models. PMID:25331898

  2. The i5K Initiative: advancing arthropod genomics for knowledge, human health, agriculture, and the environment.

    PubMed

    2013-01-01

    Insects and their arthropod relatives including mites, spiders, and crustaceans play major roles in the world's terrestrial, aquatic, and marine ecosystems. Arthropods compete with humans for food and transmit devastating diseases. They also comprise the most diverse and successful branch of metazoan evolution, with millions of extant species. Here, we describe an international effort to guide arthropod genomic efforts, from species prioritization to methodology and informatics. The 5000 arthropod genomes initiative (i5K) community met formally in 2012 to discuss a roadmap for sequencing and analyzing 5000 high-priority arthropods and is continuing this effort via pilot projects, the development of standard operating procedures, and training of students and career scientists. With university, governmental, and industry support, the i5K Consortium aspires to deliver sequences and analytical tools for each of the arthropod branches and each of the species having beneficial and negative effects on humankind. PMID:23940263

  3. The i5K Initiative: Advancing Arthropod Genomics for Knowledge, Human Health, Agriculture, and the Environment

    PubMed Central

    2013-01-01

    Insects and their arthropod relatives including mites, spiders, and crustaceans play major roles in the world’s terrestrial, aquatic, and marine ecosystems. Arthropods compete with humans for food and transmit devastating diseases. They also comprise the most diverse and successful branch of metazoan evolution, with millions of extant species. Here, we describe an international effort to guide arthropod genomic efforts, from species prioritization to methodology and informatics. The 5000 arthropod genomes initiative (i5K) community met formally in 2012 to discuss a roadmap for sequencing and analyzing 5000 high-priority arthropods and is continuing this effort via pilot projects, the development of standard operating procedures, and training of students and career scientists. With university, governmental, and industry support, the i5K Consortium aspires to deliver sequences and analytical tools for each of the arthropod branches and each of the species having beneficial and negative effects on humankind. PMID:23940263

  4. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes

    PubMed Central

    Leong, Misha; Bayless, Keith M.; Malow, Tara L.F.; Dunn, Robert R.; Trautwein, Michelle D.

    2016-01-01

    Although humans and arthropods have been living and evolving together for all of our history, we know very little about the arthropods we share our homes with apart from major pest groups. Here we surveyed, for the first time, the complete arthropod fauna of the indoor biome in 50 houses (located in and around Raleigh, North Carolina, USA). We discovered high diversity, with a conservative estimate range of 32–211 morphospecies, and 24–128 distinct arthropod families per house. The majority of this indoor diversity (73%) was made up of true flies (Diptera), spiders (Araneae), beetles (Coleoptera), and wasps and kin (Hymenoptera, especially ants: Formicidae). Much of the arthropod diversity within houses did not consist of synanthropic species, but instead included arthropods that were filtered from the surrounding landscape. As such, common pest species were found less frequently than benign species. Some of the most frequently found arthropods in houses, such as gall midges (Cecidomyiidae) and book lice (Liposcelididae), are unfamiliar to the general public despite their ubiquity. These findings present a new understanding of the diversity, prevalence, and distribution of the arthropods in our daily lives. Considering their impact as household pests, disease vectors, generators of allergens, and facilitators of the indoor microbiome, advancing our knowledge of the ecology and evolution of arthropods in homes has major economic and human health implications. PMID:26819844

  5. Geographic patterns of ground-dwelling arthropods across an ecoregional transition in the north American Southwest

    USGS Publications Warehouse

    Lightfoot, D.C.; Brantley, S.L.; Allen, C.D.

    2008-01-01

    We examined the biogeographic patterns of ground-dwelling arthropod communities across a heterogeneous semiarid region of the Southern Rio Grande Rift Valley of New Mexico. Our 3 sites included portions of 5 ecoregions, with the middle site a transition area where all ecoregions converged. We addressed the following 3 questions: (1) Do the species assemblage patterns for ground arthropods across habitats and sites conform to recognized ecoregions? (2) Are arthropod assemblages in distinct vegetation-defined habitats within an ecoregion more similar to each other or to assemblages in similar vegetation-defined habitats in other ecoregions? (3) Is there a detectable edge effect with increased arthropod diversity in the area of converging ecoregions? We encountered 442 target arthropod species from pitfall traps operating continuously for 7 years over a series of different habitats at each of the 3 sites. We examined geographic distributions of spider and cricket/grasshopper species in detail, and they showed affinities for different ecoregions, respectively. Each habitat within a study site supported a unique overall arthropod assemblage; nevertheless, different habitats at the same site were more similar to each other than they were to similar habitats at other sites. Overall arthropod species richness was greatest in the area where all 5 ecoregions converged. Arthropod species and their geographic distributions are poorly known relative to vascular plants and vertebrate animals. Findings from this research indicate that ecoregional classification is a useful tool for understanding biogeographic patterns among arthropods.

  6. Evaluating green infrastructure in urban environments using a multi-taxa and functional diversity approach.

    PubMed

    Pinho, Pedro; Correia, Otília; Lecoq, Miguel; Munzi, Silvana; Vasconcelos, Sasha; Gonçalves, Paula; Rebelo, Rui; Antunes, Cristina; Silva, Patrícia; Freitas, Catarina; Lopes, Nuno; Santos-Reis, Margarida; Branquinho, Cristina

    2016-05-01

    Forested areas within cities host a large number of species, responsible for many ecosystem services in urban areas. The biodiversity in these areas is influenced by human disturbances such as atmospheric pollution and urban heat island effect. To ameliorate the effects of these factors, an increase in urban green areas is often considered sufficient. However, this approach assumes that all types of green cover have the same importance for species. Our aim was to show that not all forested green areas are equal in importance for species, but that based on a multi-taxa and functional diversity approach it is possible to value green infrastructure in urban environments. After evaluating the diversity of lichens, butterflies and other-arthropods, birds and mammals in 31 Mediterranean urban forests in south-west Europe (Almada, Portugal), bird and lichen functional groups responsive to urbanization were found. A community shift (tolerant species replacing sensitive ones) along the urbanization gradient was found, and this must be considered when using these groups as indicators of the effect of urbanization. Bird and lichen functional groups were then analyzed together with the characteristics of the forests and their surroundings. Our results showed that, contrary to previous assumptions, vegetation density and more importantly the amount of urban areas around the forest (matrix), are more important for biodiversity than forest quantity alone. This indicated that not all types of forested green areas have the same importance for biodiversity. An index of forest functional diversity was then calculated for all sampled forests of the area. This could help decision-makers to improve the management of urban green infrastructures with the goal of increasing functionality and ultimately ecosystem services in urban areas. PMID:26777032

  7. Climate sensitivity of allergenic taxa in Central Europe associated with new climate change related forces.

    PubMed

    Deák, Aron József; Makra, László; Matyasovszky, István; Csépe, Zoltán; Muladi, Beáta

    2013-01-01

    The aim of the study was to analyse trends of the pollen season with its duration, start and end dates, as well as trends of the annual total pollen count and annual peak pollen concentration for the Szeged agglomeration in Southern Hungary. The data set covered an 11-year period (1997-2007) that included eight taxa and seven daily climate variables. Trend analysis was performed on both annual and daily bases. Trend analysis on a daily basis is a new approach that provides information on the annual cycles of the trends. To quantify the strength of the relationship between the annual cycle of the slope of a pollen concentration trend and the annual cycles of the slopes of the climate variable trends, an association measure and a multiple association measure are introduced. Individual taxa were sorted into three categories according to their climate sensitivities. These were compared with two novel climate change-related forces, namely risk potential and expansion potential due to the climate change. The total annual pollen counts indicated significant trends for 4 taxa and 3 of these 4 trends increased on a daily basis. At the same time, significant changes were detected for the pollen season characteristics of three taxa. The association measures performed well when compared to the climate change-related forces. Significant changes in pollen season characteristics were also in accordance with the risk potential and expansion potential due to the climate change. A novel procedure was applied to separate the effects of the past and current weather conditions that influence the current Ambrosia pollen concentrations. The potential effect of land use changes on pollen release of the given taxa was also discussed using the CORINE Land Cover Database. PMID:23178762

  8. A gene catalogue for post-diapause development of an anhydrobiotic arthropod Artemia franciscana

    PubMed Central

    Chen, Wie-Hua; Ge, Xiaomeng; Wang, Weiwei; Yu, Jun; Hu, Songnian

    2009-01-01

    Background Diapause is a reversible state of developmental suspension and found among diverse taxa, from plants to animals, including marsupials and some other mammals. Although previous work has accumulated ample data, the molecular mechanism underlying diapause and reactivation from it remain elusive. Results Using Artemia franciscana, a model organism to study the development of post-diapause embryos in Arthropod, we sequenced random clones up to a total of 28,039 ESTs from four cDNA libraries made from dehydrated cysts and three time points after rehydration/reactivation, which were assembled into 8,018 unigene clusters. We identified 324 differentially-expressed genes (DEGs, P < 0.05) based on pairwise comparisons of the four cDNA libraries. We identified a group of genes that are involved in an anti-water-deficit system, including proteases, protease inhibitors, heat shock proteins, and several novel members of the late embryogenesis abundant (LEA) protein family. In addition, we classified most of the up-regulated genes after cyst reactivation into metabolism, biosynthesis, transcription, and translation, and this result is consistent with the rapid development of the embryo. Some of the specific expressions of DEGs were confirmed experimentally based on quantitative real-time PCR. Conclusion We found that the first 5-hour period after rehydration is most important for embryonic reactivation of Artemia. As the total number of expressed genes increases significantly, the majority of DEGs were also identified in this period, including a group of water-deficient-induced genes. A group of genes with similar functions have been described in plant seeds; for instance, one of the novel LEA members shares ~70% amino-acid identity with an Arabidopsis EM (embryonic abundant) protein, the closest animal relative to plant LEA families identified thus far. Our findings also suggested that not only nutrition, but also mRNAs are produced and stored during cyst formation to

  9. New taxa, notes and new synonymy in Neoibidionini (Cerambycidae, Coleoptera).

    PubMed

    Martins, Ubirajara R; Galileo, Maria Helena M

    2014-01-01

    New taxa, notes, and new synonymy in Neoibidionini (Cerambycidae, Coleoptera) are given. New taxa are described from Ecuador: Compsibidion inflatum sp. nov., Bezarkia gen. nov. and B. suturalis sp. nov., Corimbion antennatum sp. nov. and Neocompsa muira sp. nov.; from México: Neocompsa chiapensis sp. nov., and from French Guyana: Kunaibidion giesberti sp. nov. Pygmodeon maculatum Martins & Galileo, 2012 is considered a new synonym of Heterachthes xyleus Martins, 1974 which is transferred to the genus Pygmodeon as a new combination. Notes on variability and new records of Asynapteron equatorianum (Martins, 1960) are presented. PMID:24869549

  10. Waptia and the Diversification of Brood Care in Early Arthropods.

    PubMed

    Caron, Jean-Bernard; Vannier, Jean

    2016-01-11

    Brood care, including the carrying of eggs or juveniles, is a form of parental care, which, like other parental traits [1], enhances offspring fitness with variable costs and benefits to the parents [2]. Attempts to understand why and how parental care evolved independently in numerous animal groups often emphasize the role of environmental pressures such as predation, ephemeral resources, and, more generally, the harshness of environment. The fossil record can, in principle, provide minimum age constraints on the evolution of life-history traits, including brood care and key information on the reproductive strategies of extinct organisms. New, exceptionally preserved specimens of the weakly sclerotized arthropod Waptia fieldensis from the middle Cambrian (ca. 508 million years ago) Burgess Shale, Canada, provide the oldest example of in situ eggs with preserved embryos in the fossil record. The relatively small clutch size, up to 24 eggs, and the relatively large diameter of individual eggs, some over 2 mm, contrast with the high number of small eggs-found without preserved embryos-in the bivalved bradoriid arthropod Kunmingella douvillei from the Chengjiang biota (ca. 515 million years ago). The presence of these two different parental strategies suggests a rapid evolution of a variety of modern-type life-history traits, including extended investment in offspring survivorship, soon after the Cambrian emergence of animals. Together with previously described brooded eggs in ostracods from the Upper Ordovician (ca. 450 million years ago), these new findings suggest that the presence of a bivalved carapace played a key role in the early evolution of parental care in arthropods. PMID:26711492

  11. Arthropod phylogeny revisited, with a focus on crustacean relationships.

    PubMed

    Koenemann, Stefan; Jenner, Ronald A; Hoenemann, Mario; Stemme, Torben; von Reumont, Björn M

    2010-01-01

    Higher-level arthropod phylogenetics is an intensely active field of research, not least as a result of the hegemony of molecular data. However, not all areas of arthropod phylogenetics have so far received equal attention. The application of molecular data to infer a comprehensive phylogeny of Crustacea is still in its infancy, and several emerging results are conspicuously at odds with morphology-based studies. In this study, we present a series of molecular phylogenetic analyses of 88 arthropods, including 57 crustaceans, representing all the major lineages, with Onychophora and Tardigrada as outgroups. Our analyses are based on published and new sequences for two mitochondrial markers, 16S rDNA and cytochrome c oxidase subunit I (COI), and the nuclear ribosomal gene 18S rDNA. We designed our phylogenetic analyses to assess the effects of different strategies of sequence alignment, alignment masking, nucleotide coding, and model settings. Our comparisons show that alignment optimization of ribosomal markers based on secondary structure information can have a radical impact on phylogenetic reconstruction. Trees based on optimized alignments recover monophyletic Arthropoda (excluding Onychophora), Pancrustacea, Malacostraca, Insecta, Myriapoda and Chelicerata, while Maxillopoda and Hexapoda emerge as paraphyletic groups. Our results are unable to resolve the highest-level relationships within Arthropoda, and none of our trees supports the monophyly of Myriochelata or Mandibulata. We discuss our results in the context of both the methodological variations between different analyses, and of recently proposed phylogenetic hypotheses. This article offers a preliminary attempt to incorporate the large diversity of crustaceans into a single molecular phylogenetic analysis, assessing the robustness of phylogenetic relationships under varying analysis parameters. It throws into sharp relief the relative strengths and shortcomings of the combined molecular data for

  12. Reconstructing the diet of a 505-million-year-old arthropod: Sidneyia inexpectans from the Burgess Shale fauna.

    PubMed

    Zacaï, Axelle; Vannier, Jean; Lerosey-Aubril, Rudy

    2016-03-01

    The feeding ecology of the 505-million-year-old arthropod Sidneyia inexpectans from the middle Cambrian (Series 3, Stage 5) Burgess Shale fauna (British Columbia, Canada) is revealed by three lines of evidence: the structure of its digestive system, the fossilized contents of its gut and the functional anatomy of its appendages. The digestive tract of Sidneyia is straight, tubular and relatively narrow in the trunk region. It is enlarged into a pear-shaped area in the cephalic region and stretches notably to form a large pocket in the abdomen. The mouth is ventral, posteriorly directed and leads to the midgut via a short tubular structure interpreted as the oesophagus. Anteriorly, three pairs of glands with internal, branching tubular structures open into the digestive tract. These glands have equivalents in various Cambrian arthropod taxa (e.g. naraoiids) and modern arthropods. Their primary function was most likely to digest and assimilate food. The abdominal pocket of Sidneyia concentrates undigested skeletal elements and various residues. It is interpreted here as the functional analogue of the stercoral pocket of some extant terrestrial arachnids (e.g. Araneae, Solifugae), whose primary function is to store food residuals and excretory material until defecation. Analysis of the gut contents indicates that Sidneyia fed largely on small ptychopariid trilobites, brachiopods, possibly agnostids, worms and other undetermined animals. Sidneyia was primarily a durophagous carnivore with predatory and/or scavenging habits, feeding on small invertebrates that lived at the water-sediment interface. There is no evidence for selective feeding. Its food items (e.g. living prey or dead material) were grasped and manipulated ventrally by its anterior appendages, then macerated into ingestible fragments and conveyed to the mouth via the converging action of strong molar-like gnathobases. Digestion probably took place within the anterior midgut via enzymes secreted in the

  13. Interactions among predators and the cascading effects of vertebrate insectivores on arthropod communities and plants.

    PubMed

    Mooney, Kailen A; Gruner, Daniel S; Barber, Nicholas A; Van Bael, Sunshine A; Philpott, Stacy M; Greenberg, Russell

    2010-04-20

    Theory on trophic interactions predicts that predators increase plant biomass by feeding on herbivores, an indirect interaction called a trophic cascade. Theory also predicts that predators feeding on predators, or intraguild predation, will weaken trophic cascades. Although past syntheses have confirmed cascading effects of terrestrial arthropod predators, we lack a comprehensive analysis for vertebrate insectivores-which by virtue of their body size and feeding habits are often top predators in these systems-and of how intraguild predation mediates trophic cascade strength. We report here on a meta-analysis of 113 experiments documenting the effects of insectivorous birds, bats, or lizards on predaceous arthropods, herbivorous arthropods, and plants. Although vertebrate insectivores fed as intraguild predators, strongly reducing predaceous arthropods (38%), they nevertheless suppressed herbivores (39%), indirectly reduced plant damage (40%), and increased plant biomass (14%). Furthermore, effects of vertebrate insectivores on predatory and herbivorous arthropods were positively correlated. Effects were strongest on arthropods and plants in communities with abundant predaceous arthropods and strong intraguild predation, but weak in communities depauperate in arthropod predators and intraguild predation. The naturally occurring ratio of arthropod predators relative to herbivores varied tremendously among the studied communities, and the skew to predators increased with site primary productivity and in trees relative to shrubs. Although intraguild predation among arthropod predators has been shown to weaken herbivore suppression, we find this paradigm does not extend to vertebrate insectivores in these communities. Instead, vertebrate intraguild preda-tion is associated with strengthened trophic cascades, and insectivores function as dominant predators in terrestrial plant-arthropod communities. PMID:20368418

  14. Determining phylogenetic networks from inter-taxa distances.

    PubMed

    Bordewich, Magnus; Semple, Charles

    2016-08-01

    We consider the problem of determining the topological structure of a phylogenetic network given only information about the path-length distances between taxa. In particular, one of the main results of the paper shows that binary tree-child networks are essentially determined by such information. PMID:26666756

  15. IDENTIFICATION OF ERYTHROXYLUM TAXA BY AFLP DNA ANALYSIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Erythroxylum coca, indigenous to the Andean region of South America, is grown historically as a source of homeopathic medicine. However, in the last century, cultivation of E. coca var. coca and three closely-related taxa for the production of illicit cocaine has become a major global problem. Two s...

  16. Eliciting the Functional Taxonomy from protein annotations and taxa

    PubMed Central

    Falda, Marco; Lavezzo, Enrico; Fontana, Paolo; Bianco, Luca; Berselli, Michele; Formentin, Elide; Toppo, Stefano

    2016-01-01

    The advances of omics technologies have triggered the production of an enormous volume of data coming from thousands of species. Meanwhile, joint international efforts like the Gene Ontology (GO) consortium have worked to provide functional information for a vast amount of proteins. With these data available, we have developed FunTaxIS, a tool that is the first attempt to infer functional taxonomy (i.e. how functions are distributed over taxa) combining functional and taxonomic information. FunTaxIS is able to define a taxon specific functional space by exploiting annotation frequencies in order to establish if a function can or cannot be used to annotate a certain species. The tool generates constraints between GO terms and taxa and then propagates these relations over the taxonomic tree and the GO graph. Since these constraints nearly cover the whole taxonomy, it is possible to obtain the mapping of a function over the taxonomy. FunTaxIS can be used to make functional comparative analyses among taxa, to detect improper associations between taxa and functions, and to discover how functional knowledge is either distributed or missing. A benchmark test set based on six different model species has been devised to get useful insights on the generated taxonomic rules. PMID:27534507

  17. STORAGE BEHAVIOR OF SEEDS FROM NATIVE HAWAIIAN TAXA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ex situ conservation is required to preserve genetic diversity of the 956 species native to Hawai’i (89% endemism, 30% federally-listed as endangered or threatened). Optimizing storage procedures to maximize seed longevity is critical to the effort. Storage behavior of seeds from about 280 taxa was ...

  18. Eliciting the Functional Taxonomy from protein annotations and taxa.

    PubMed

    Falda, Marco; Lavezzo, Enrico; Fontana, Paolo; Bianco, Luca; Berselli, Michele; Formentin, Elide; Toppo, Stefano

    2016-01-01

    The advances of omics technologies have triggered the production of an enormous volume of data coming from thousands of species. Meanwhile, joint international efforts like the Gene Ontology (GO) consortium have worked to provide functional information for a vast amount of proteins. With these data available, we have developed FunTaxIS, a tool that is the first attempt to infer functional taxonomy (i.e. how functions are distributed over taxa) combining functional and taxonomic information. FunTaxIS is able to define a taxon specific functional space by exploiting annotation frequencies in order to establish if a function can or cannot be used to annotate a certain species. The tool generates constraints between GO terms and taxa and then propagates these relations over the taxonomic tree and the GO graph. Since these constraints nearly cover the whole taxonomy, it is possible to obtain the mapping of a function over the taxonomy. FunTaxIS can be used to make functional comparative analyses among taxa, to detect improper associations between taxa and functions, and to discover how functional knowledge is either distributed or missing. A benchmark test set based on six different model species has been devised to get useful insights on the generated taxonomic rules. PMID:27534507

  19. The hominin fossil record: taxa, grades and clades

    PubMed Central

    Wood, Bernard; Lonergan, Nicholas

    2008-01-01

    This paper begins by reviewing the fossil evidence for human evolution. It presents summaries of each of the taxa recognized in a relatively speciose hominin taxonomy. These taxa are grouped in grades, namely possible and probable hominins, archaic hominins, megadont archaic hominins, transitional hominins, pre-modern Homo and anatomically modern Homo. The second part of this contribution considers some of the controversies that surround hominin taxonomy and systematics. The first is the vexed question of how you tell an early hominin from an early panin, or from taxa belonging to an extinct clade closely related to the Pan-Homo clade. Secondly, we consider how many species should be recognized within the hominin fossil record, and review the philosophies and methods used to identify taxa within the hominin fossil record. Thirdly, we examine how relationships within the hominin clade are investigated, including descriptions of the methods used to break down an integrated structure into tractable analytical units, and then how cladograms are generated and compared. We then review the internal structure of the hominin clade, including the problem of how many subclades should be recognized within the hominin clade, and we examine the reliability of hominin cladistic hypotheses. The last part of the paper reviews the concepts of a genus, including the criteria that should be used for recognizing genera within the hominin clade. PMID:18380861

  20. The Arthropod-Borne Animal Diseases Research Laboratory: Research Program Update and Current Status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mission of the Arthropod-Borne Animal Diseases Research Laboratory (ABADRL) located in Laramie, Wyoming, is to solve major endemic, emerging, and exotic arthropod-borne disease problems in U.S. livestock. The ABADRL has three 5-year project plans under two ARS National Research Programs; Animal ...

  1. "Bugs on Bugs": An Inquiry-Based, Collaborative Activity to Learn Arthropod & Microbial Biodiversity

    ERIC Educational Resources Information Center

    Lampert, Evan C.; Morgan, Jeanelle M.

    2015-01-01

    Diverse communities of arthropods and microbes provide humans with essential ecosystem goods and services. Arthropods are the most diverse and abundant macroscopic animals on the planet, and many remain to be discovered. Much less is known about microbial diversity, despite their importance as free-living species and as symbionts. We created…

  2. Genetic Variation in Functional Traits Influences Arthropod Community Composition in Aspen (Populus tremula L.)

    PubMed Central

    Robinson, Kathryn M.; Ingvarsson, Pär K.; Jansson, Stefan; Albrectsen, Benedicte R.

    2012-01-01

    We conducted a study of natural variation in functional leaf traits and herbivory in 116 clones of European aspen, Populus tremula L., the Swedish Aspen (SwAsp) collection, originating from ten degrees of latitude across Sweden and grown in a common garden. In surveys of phytophagous arthropods over two years, we found the aspen canopy supports nearly 100 morphospecies. We identified significant broad-sense heritability of plant functional traits, basic plant defence chemistry, and arthropod community traits. The majority of arthropods were specialists, those coevolved with P. tremula to tolerate and even utilize leaf defence compounds. Arthropod abundance and richness were more closely related to plant growth rates than general chemical defences and relationships were identified between the arthropod community and stem growth, leaf and petiole morphology, anthocyanins, and condensed tannins. Heritable genetic variation in plant traits in young aspen was found to structure arthropod community; however no single trait drives the preferences of arthropod folivores among young aspen genotypes. The influence of natural variation in plant traits on the arthropod community indicates the importance of maintaining genetic variation in wild trees as keystone species for biodiversity. It further suggests that aspen can be a resource for the study of mechanisms of natural resistance to herbivores. PMID:22662190

  3. Avirulence effector discovery in a plant galling and plant parasitic arthropod, the Hessian fly (Mayetiola destructor)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly specialized obligate plant-parasites exist within several groups of arthropods (insects and mites). Many of these are important pests, but the molecular basis of their parasitism and its evolution are poorly understood. One hypothesis is that plant parasitic arthropods use effector proteins...

  4. The Arthropod-borne Animal Diseases Unit: research program update and status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To accomplish the continuing research mission of the Arthropod Borne Animal Diseases Unit (ABADRU) in solving major endemic, emerging, and exotic arthropod-borne disease problems in livestock, the Unit has completed the move to Manhattan, KS. The ABADRU is one of five units at the Center for Grain a...

  5. Arthropods in no-tillage soybean agroecosystems: Community composition and ecosystem interactions

    NASA Astrophysics Data System (ADS)

    House, Garfield J.; Stinner, Benjamin R.

    1983-01-01

    Sampling data are provided and concepts discussed regarding soil and foliage arthropod communities in conventional and no-tillage soybean agroecosystems Soil arthropod communities from the two cropping systems were also compared with that from an adjacent old field. Biweekly arthropod samples were collected from conventional, no-tillage, and old-field systems Soil arthropods were sampled by quadrat and pitfall trap methods, foliage arthropods were collected by sweep net Quadrat sampling revealed that ground beetle number, species diversity, and biomass were significantly higher ( P<0.05) in no-tillage than in conventional tillage systems. Pitfall trap data indicated higher densities and species diversity for most major soil macro-arthropod guilds Foliage arthropod guilds from no-tillage treatments showed higher species diversity throughout the growing season than those of conventional tillage, possibly because of greater structural diversity provided by weeds and litter in notillage systems No-tillage systems supported a larger and more diverse arthropod community than conventionally grown soybeans, suggesting a need for pest management strategies that simultaneously consider many variables. Both foliar grazing and leaf nitrogen content were higher in conventional than in no-tillage systems, indicating a possible causal connection between soil tillage and insect herbivory rates

  6. The effects of ingested mammalian blood factors on vector arthropod immunity and physiology

    PubMed Central

    Pakpour, Nazzy; Akman-Anderson, Leyla; Vodovotz, Yoram; Luckhart, Shirley

    2013-01-01

    The blood feeding behavior of disease-transmitting arthropods creates a unique intersection between vertebrate and invertebrate physiology. Here, we review host blood-derived factors that persist through blood digestion to affect the lifespan, reproduction, and immune responses of some of the most common arthropod vectors of human disease. PMID:23370408

  7. The i5K Initiative: Advancing arthropod genomics for knowledge, human health, agriculture, and the environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Insects and their arthropod relatives including mites, spiders, and crustaceans, play major roles in the world’s terrestrial, aquatic, and marine ecosystems. Arthropods compete with humans for food and transmit devastating diseases. They also comprise the most diverse and successful branch of metazo...

  8. Procedures for identification of arthropod-borne viruses*

    PubMed Central

    Casals, Jordi

    1961-01-01

    Owing to the existence of antigenic groups and to the consequent characteristics of the immune response of a host to grouped viruses, certain logical steps are advisable in the process of identification of an arthropod-borne (arbor) virus. The first of these steps is the determination of the arthropod-borne nature of the virus. Since no antigenic property is known to be common to all arbor viruses, the decision is based on other biological properties and on the circumstances of isolation. The second step is determination of the antigenic group. For this are used hyperimmune sera with considerable cross-reactivity within the group, as well as the test that gives the most overlap. The third step is determination of type within the group. Simple immune sera and the least cross-reactive test are used at this step. Viruses that belong in minor groups or are ungrouped often constitute a big problem owing to the fact that, once the major groups have been eliminated from further consideration, comparative studies must be conducted with practically all the remaining viruses before a definitive answer is reached. PMID:13691234

  9. Early History of Arthropod and Vascular Plant Associations

    NASA Astrophysics Data System (ADS)

    Labandeira, Conrad C.

    Although research on modern plant-arthropod associations is one of the cornerstones of biodiversity studies, very little of that interest has percolated down to the fossil record. Much of this neglect is attributable to dismissal of Paleozoic plant-arthropod interactions as being dominated by detritivory, with substantive herbivory not emerging until the Mesozoic. Recent examination of associations from some of the earliest terrestrial communities indicates that herbivory probably extends to the Early Devonian, in the form of spore feeding and piercing-and-sucking. External feeding on pinnule margins and the intimate and intricate association of galling are documented from the Middle and Late Pennsylvanian, respectively. During the Early Permian, the range of external foliage feeding extended to hole feeding and skeletonization and was characterized by the preferential targeting of certain seed plants. At the close of the Paleozoic, surface fluid feeding was established, but there is inconclusive evidence for mutualistic relationships between insect pollinivores and seed plants. These data are gleaned from the largely separate trace-fossil records of gut contents, coprolites, and plant damage and the body-fossil records of plant reproductive and vegetative structures, insect mouthparts, and ovipositors. While these discoveries accentuate the potential for identifying particular associations, the greatest theoretical demand is to establish the spectrum and level of intensity for the emergence of insect herbivory in a range of environments during the Pennsylvanian and Permian.

  10. [Arthropod community structures in transgenic Bt cotton fields].

    PubMed

    Wei, G; Cui, L; Zhang, X; Liu, S; Lü, N; Zhang, Q

    2001-08-01

    Arthropod community structures were investigated in transgenic Bt cultivars, Bollgard(B) and Chinese cotton 30 (CC30), and common cultivars, control (C) and no control (NC) cotton field in North China in 1998. The results showed that compared with common cultivars, the species richness and the number of total individual of arthropod community in transgenic Bt cultivars field were reduced 2.4-16.3% and 71.0-78.3% respectively, in which dominant species in phytophagous subcommunity varied. The number of individual of predatory and parastic subcommunity were all increased. The similarity coefficient between CC30 and NC was 0.8243, B and NC 0.7320, B and C 0.3380, C and NC 0.3128, CC30 and C 0.2665. The order of diversity and evenness value of these were CC30 (2.3712 and 0.6428), NC (2.3654 and 0.6251), B (2.1364 and 0.5791), and C (1.0877 and 0.2949), their dominant value was 0.8726 (C), 0.3528(B), 0.1178(NC) and 0.1048 (CC30) respectively. It was concluded that different integrated pest management (IPM) strategy should be implemented in transgenic Bt cotton instead of common variety cotton field. PMID:11758387

  11. [Natural concentration of antimalaric components in Tropical arthropods (in vitro)].

    PubMed

    Chinchilla-Carmona, Misael; Guerrero Bermúdez, Olga Marta; Tamayo-Castillo, Giselle; Appel, Ana Sittenfeld; Jiménez-Somarribas, Alberto; Valerio-Campos, Idalia

    2008-06-01

    Alcohol, hexane and dichlorometane extracts of 751 samples of Costa Rican arthropods were studied for the presence of antimalaric components. With Plasmodium berghei we set an in vitro model in which the effect of the extract was determined by staining of the parasites with cresil brilliant blue. Active extracts at concentration of 50 mg or less, were considered positive. Promissory extracts were found in the orders Lepidoptera (24.1%), Coleoptera (32.8%), Hemiptera (38.5%) and Polydesmida (81.3%). Since most of the Lepidoptera samples were in the immature stages, the relation with the host plant was analyzed. Cannaceae, Flacourtiaceae, Crisobalanaceae, Lauraceae, Fagaceae, Ulmaceae, Rosaceae, Asteraceae, Rubiaceae, Lauraceae and Caprifoliaceae were related with the Lepidoptera larvae, and an antimalaric effect has been reported in most of these families. In the orders Polydesmida, Opiliones and Blattodea, the extract from adults also had some important effect, probably because all of them fed on plants. Polydesmida and Opiliones have chemical substances that probably serve as defensive purposes; these chemicals could also have some antiparasitic effect. Therefore, the detection of antimalaric components in arthropod species led to the identification of plants with promissory antimalaric components. PMID:19256421

  12. Arthropod Phylogenetics in Light of Three Novel Millipede (Myriapoda: Diplopoda) Mitochondrial Genomes with Comments on the Appropriateness of Mitochondrial Genome Sequence Data for Inferring Deep Level Relationships

    PubMed Central

    Brewer, Michael S.; Swafford, Lynn; Spruill, Chad L.; Bond, Jason E.

    2013-01-01

    Background Arthropods are the most diverse group of eukaryotic organisms, but their phylogenetic relationships are poorly understood. Herein, we describe three mitochondrial genomes representing orders of millipedes for which complete genomes had not been characterized. Newly sequenced genomes are combined with existing data to characterize the protein coding regions of myriapods and to attempt to reconstruct the evolutionary relationships within the Myriapoda and Arthropoda. Results The newly sequenced genomes are similar to previously characterized millipede sequences in terms of synteny and length. Unique translocations occurred within the newly sequenced taxa, including one half of the Appalachioria falcifera genome, which is inverted with respect to other millipede genomes. Across myriapods, amino acid conservation levels are highly dependent on the gene region. Additionally, individual loci varied in the level of amino acid conservation. Overall, most gene regions showed low levels of conservation at many sites. Attempts to reconstruct the evolutionary relationships suffered from questionable relationships and low support values. Analyses of phylogenetic informativeness show the lack of signal deep in the trees (i.e., genes evolve too quickly). As a result, the myriapod tree resembles previously published results but lacks convincing support, and, within the arthropod tree, well established groups were recovered as polyphyletic. Conclusions The novel genome sequences described herein provide useful genomic information concerning millipede groups that had not been investigated. Taken together with existing sequences, the variety of compositions and evolution of myriapod mitochondrial genomes are shown to be more complex than previously thought. Unfortunately, the use of mitochondrial protein-coding regions in deep arthropod phylogenetics appears problematic, a result consistent with previously published studies. Lack of phylogenetic signal renders the

  13. Where Is the Extended Phenotype in the Wild? The Community Composition of Arthropods on Mature Oak Trees Does Not Depend on the Oak Genotype

    PubMed Central

    Gossner, Martin M.; Brändle, Martin; Brandl, Roland; Bail, Johannes; Müller, Jörg; Opgenoorth, Lars

    2015-01-01

    Through a series of common garden experiments, it has been shown that heritable phenotypic differences between individual trees can affect arthropod communities. However, field studies under heterogeneous environmental conditions remain rare. In the present study, we investigated the genetic constitution of 121 mature oak host trees at different trophic levels from 10 sites across Bavaria, southern Germany and their associated insect communities. A total of 23,576 individuals representing 395 species of beetles and true bugs were evaluated. In particular, we determined whether the composition of arthropod communities is related to the oak genotype and whether the strength of the relationships decreases from lower to higher trophic levels, such as for phytophagous, xylophagous, zoophagous, and mycetophagous species. The genetic differentiation of oaks was assessed using eight microsatellite markers. We found no significant influence of the oak genotype on neither the full beetle and true bug community nor on any of the analyzed trophic guilds. In contrast, the community composition of the insects was highly related to the space and climate, such that the community similarity decreased with increases in spatial distance and climatic differences. The relationship with space and climate was much stronger in beetles than in true bugs, particularly in mycetophagous species. Our results suggest that spatial processes override the genetic effects of the host plant in structuring arthropod communities on oak trees. Because we used neutral markers, we cannot exclude the possibility that trait-specific markers may reveal a genetic imprint of the foundation tree species on the composition of the arthropod community. However, based on the strength of the spatial patterns in our data set, we assume that genetic differences among oaks are less important in the structuring of arthropod communities. Future whole-genome studies are required to draw a final conclusion. PMID:25635387

  14. Introduction to the Arizona Sky Island Arthropod Project (ASAP): Systematics, Biogeography, Ecology, and Population Genetics of Arthropods of the Madrean Sky Islands

    PubMed Central

    Moore, Wendy; Meyer, Wallace M.; Eble, Jeffrey A.; Franklin, Kimberly; Wiens, John F.; Brusca, Richard C.

    2014-01-01

    The Arizona Sky Island Arthropod Project (ASAP) is a new multi-disciplinary research program at the University of Arizona that combines systematics, biogeography, ecology, and population genetics to study origins and patterns of arthropod diversity along elevation gradients and among mountain ranges in the Madrean Sky Island Region. Arthropods represent taxonomically and ecologically diverse organisms that drive key ecosystem processes in this mountain archipelago. Using data from museum specimens and specimens we obtain during long-term collecting and monitoring programs, ASAP will document arthropod species across Arizona's Sky Islands to address a number of fundamental questions about arthropods of this region. Baseline data will be used to determine climatic boundaries for target species, which will then be integrated with climatological models to predict future changes in arthropod communities and distributions in the wake of rapid climate change. ASAP also makes use of the natural laboratory provided by the Sky Islands to investigate ecological and genetic factors that influence diversification and patterns of community assembly. Here, we introduce the project, outline overarching goals, and describe preliminary data from the first year of sampling ground-dwelling beetles and ants in the Santa Catalina Mountains. PMID:25505938

  15. Community responses of arthropods to a range of traditional and manipulated grazing in shortgrass steppe.

    PubMed

    Newbold, T A Scott; Stapp, Paul; Levensailor, Katherine E; Derner, Justin D; Lauenroth, William K

    2014-06-01

    Responses of plants to grazing are better understood, and more predictable, than those of consumers in North American grasslands. In 2003, we began a large-scale, replicated experiment that examined the effects of grazing on three important arthropod groups-beetles, spiders, and grasshoppers-in shortgrass steppe of north-central Colorado. We investigated whether modifications of the intensity and seasonality of livestock grazing alter the structure and diversity of macroarthropod communities compared with traditional grazing practices. Treatments represented a gradient of grazing intensity by cattle and native herbivores: long-term grazing exclosures; moderate summer grazing (the traditional regime); intensive spring grazing; intensive summer grazing; and moderately summer-grazed pastures also inhabited by black-tailed prairie dogs (Cynomys ludovicianus Ord). Beetles and spiders were the most common groups captured, comprising 60% and 21%, respectively, of 4,378 total pitfall captures. Grasshopper counts were generally low, with 3,799 individuals observed and densities <4 m(-2). Two years after treatments were applied, vegetation structure differed among grazing treatments, responding not only to long-term grazing conditions, but also to the short-term, more-intensive grazing manipulations. In response, arthropods were, in general, relatively insensitive to these grazing-induced structural changes. However, species-level analyses of one group (Tenebrionidae) revealed both positive and negative effects of grazing treatments on beetle richness and activity-density. Importantly, these responses to grazing were more pronounced in a year when spring-summer rainfall was low, suggesting that both grazing and precipitation-which together may create the greatest heterogeneity in vegetation structure-are drivers of consumer responses in this system. PMID:24780073

  16. Co-occurrence analyses show that non-random community structure is disrupted by fire in two groups of soil arthropods (Isopoda Oniscidea and Collembola)

    NASA Astrophysics Data System (ADS)

    Pitzalis, Monica; Luiselli, Luca; Bologna, Marco A.

    2010-01-01

    In this paper, we tested the hypothesis that natural catastrophes may destroy non-random community structure in natural assemblages of organisms. As a study system, we selected fire as the catastrophic event, and two groups of soil arthropods (Collembola and Isopoda Oniscidea) as target organisms. By co-occurrence analyses and Monte Carlo simulations of niche overlap analysis (C-score, with fixed-equiprobable model; RA2 and RA3 algorithms) we evaluated whether the community structure of these two groups were random/non-random at three unburnt sites and at three neighbour burnt sites that were devastated by a large-scale fire in summer 2000. Both taxa experienced a remarkable reduction in the number of species sampled in burnt versus unburnt sites, but the difference among sites was not statistically significant for Oniscidea. We determined that community structure was clearly non-random at the unburnt sites for both Collembola (according to RA3 algorithm) and Isopoda Oniscidea (according to co-occurrence analysis) and that, as predicted by theory, the catastrophic event did deeply alter the community structure by removing the non-random organization of the species interactions. We also observed a shift from segregation to aggregation/randomness in soil arthropods communities affected by fire, a pattern that was similar to that observed in natural communities of organisms perturbed by the introduction of alien species, thus indicating that this pattern may be generalizable when alteration of communities may occur.

  17. Arthropods and associated arthropod-borne diseases transmitted by migrating birds. The case of ticks and tick-borne pathogens.

    PubMed

    Sparagano, Olivier; George, David; Giangaspero, Annunziata; Špitalská, Eva

    2015-09-30

    Geographic spread of parasites and pathogens poses a constant risk to animal health and welfare, particularly given that climate change is expected to potentially expand appropriate ranges for many key species. The spread of deleterious organisms via trade routes and human travelling is relatively closely controlled, though represents only one possible means of parasite/pathogen distribution. The transmission via natural parasite/pathogen movement between geographic locales, is far harder to manage. Though the extent of such movement may be limited by the relative inability of many parasites and pathogens to actively migrate, passive movement over long distances may still occur via migratory hosts. This paper reviews the potential role of migrating birds in the transfer of ectoparasites and pathogens between geographic locales, focusing primarily on ticks. Bird-tick-pathogen relationships are considered, and evidence provided of long-range parasite/pathogen transfer from one location to another during bird migration events. As shown in this paper not only many different arthropod species are carried by migrating birds but consequently these pests carry many different pathogens species which can be transmitted to the migrating birds or to other animal species when those arthropods are dropping during these migrations. Data available from the literature are provided highlighting the need to understand better dissemination paths and disease epidemiology. PMID:26343302

  18. Identification of polyamine-responsive bacterioplankton taxa in South Atlantic Bight.

    PubMed

    Lu, Xinxin; Sun, Shulei; Hollibaugh, James T; Mou, Xiaozhen

    2015-12-01

    Putrescine and spermidine are short-chained aliphatic polyamines (PAs) that are ubiquitously distributed in seawater. These compounds may be important sources of dissolved organic carbon and nitrogen for marine bacterioplankton. Here, we used pyrotag sequencing to quantify the response of bacterioplankton to putrescine and spermidine amendments in microcosms established using surface waters collected at various stations in the South Atlantic Bight in October 2011. Our analysis showed that PA-responsive bacterioplankton consisted of bacterial taxa that are typically dominant in marine systems. Rhodobacteraceae (Alphaproteobacteria) was the taxon most responsive to PA additions at the nearshore site. Gammaproteobacteria of the families Piscirickettsiaceae; Vibrionaceae; and Vibrionaceae and Pseudoalteromonadaceae, were the dominant PA-responsive taxa in samples from the river-influenced coastal station, offshore station and open ocean station, respectively. The spatial variability of PA-responsive taxa may be attributed to differences in composition of the initial bacterial community and variations of in situ physiochemical conditions among sites. Our results also provided the first empirical evidence that Gammaproteobacteria might play an important role in PA transformation in marine systems. PMID:26109269

  19. New genome size estimates of 134 species of arthropods.

    PubMed

    Hanrahan, Shawn Jason; Johnston, J Spencer

    2011-08-01

    Insect genome size diversity remains poorly sampled, with sparse and sporadic sampling of a few select orders and with many orders unrepresented or underrepresented in the genome size database. Here, we present 134 genome size estimates for 18 orders, including the first ever genome size estimates for eight orders, 38 families, 102 genera, and 131 species. Also reported here are three insect species genome size estimates that are corrections for unpublished genome size values that made it into the literature, including the smallest arthropod genome of the two spot spider mite (1C = 91 Mb). These estimates range from 91 to 7,752 Mb and provide a broader picture of genome size variation within Insecta and among all Arthropods. Proposed developmental constraints for holometabolous insect genome sizes are supported, with the majority of the species examined falling well under the hypothesized 1,978 Mb (2 pg) limit. The only exceptions occur in the highly diverse beetles (Coleoptera) (154 < 1C < 2,578) and the Mecoptera (1,890 < 1C < 2,134). Hemimetabolous orders include species with larger genomes. Of these, the Orthopteran genomes remain the largest (675 < 1C < 7,752). Hemipteran genomes are smaller (407 < 1C < 1,230), but with a very notable exception, the Cicadidae family, with bloated genomes (5,238 < 1C < 7,000 Mb) of a size previously known to exist only within Orthoptera. The genome sizes in all other Hemimetabolous orders (521 Mb < 1C < 3,860 Mb) fall within the range exhibited by the Hemiptera. New preparations and procedures for insect genome estimates with frozen material are described and discussed. To further improve and extend the number and quality of arthropod genome size estimates, a new flow cytometry insect standard, Blattaria: Periplaneta americana♂ (1C = 3,338 Mb) is established for genome size determination of insect genomes in excess of 2,000 Mb. PMID:21877225

  20. Perspectives on the evolutionary ecology of arthropod antimicrobial peptides.

    PubMed

    Rolff, Jens; Schmid-Hempel, Paul

    2016-05-26

    Antimicrobial peptides (AMPs) are important elements of the innate immune defence in multicellular organisms that target and kill microbes. Here, we reflect on the various points that are raised by the authors of the 11 contributions to a special issue of Philosophical Transactions on the 'evolutionary ecology of arthropod antimicrobial peptides'. We see five interesting topics emerging. (i) AMP genes in insects, and perhaps in arthropods more generally, evolve much slower than most other immune genes. One explanation refers to the constraints set by AMPs being part of a finely tuned defence system. A new view argues that AMPs are under strong stabilizing selection. Regardless, this striking observation still invites many more questions than have been answered so far. (ii) AMPs almost always are expressed in combinations and sometimes show expression patterns that are dependent on the infectious agent. While it is often assumed that this can be explained by synergistic interactions, such interactions have rarely been demonstrated and need to be studied further. Moreover, how to define synergy in the first place remains difficult and needs to be addressed. (iii) AMPs play a very important role in mediating the interaction between a host and its mutualistic or commensal microbes. This has only been studied in a very small number of (insect) species. It has become clear that the very same AMPs play different roles in different situations and hence are under concurrent selection. (iv) Different environments shape the physiology of organisms; especially the host-associated microbial communities should impact on the evolution host AMPs. Studies in social insects and some organisms from extreme environments seem to support this notion, but, overall, the evidence for adaptation of AMPs to a given environment is scant. (v) AMPs are considered or already developed as new drugs in medicine. However, bacteria can evolve resistance to AMPs. Therefore, in the light of our

  1. Evolution of cyanobacterial morphotypes: Taxa required for improved phylogenomic approaches.

    PubMed

    Schirrmeister, Bettina E; Anisimova, Maria; Antonelli, Alexandre; Bagheri, Homayoun C

    2011-07-01

    Within prokaryotes cyanobacteria represent one of the oldest and morphologically most diverse phyla on Earth. The rise of oxygen levels in the atmosphere 2.32-2.45 billion years ago is assigned to the photosynthetic activity of ancestors from this phylum. Subsequently cyanobacteria were able to adapt to various habitats evolving a comprehensive set of different morphotypes. In a recent study we showed that this evolution is not a gradual transition from simple unicellular to more complex multicellular forms as often assumed. Instead complexity was lost several times and regained at least once. An understanding of the genetic basis of these transitions would be further strengthened by phylogenomic approaches. However, considering that new methods for phylogenomic analyses are emerging, it is unfortunate that genomes available today are comprised of an unbalanced sampling of taxa. We propose avenues to remedy this by identifying taxa that would improve the representation of phylogenetic diversity in this phylum. PMID:21966561

  2. Spatial genetic structure of Aquilegia taxa endemic to the island of Sardinia

    PubMed Central

    Garrido, J. L.; Fenu, G.; Mattana, E.; Bacchetta, G.

    2012-01-01

    Background and Aims The Mediterranean Basin is one of the most important regions for the Earth's plant biodiversity; however, the scarcity of studies on fine scale patterns of genetic variation in this region is striking. Here, an assessment is made of the spatial genetic structure of all known locations of the three Sardinian endemic species of Aquilegia in order to determine the relative roles of gene flow and genetic drift as underlying evolutionary forces canalizing the divergence of Sardinian Aquilegia taxa, and to see if the spatial genetic structure found fits the current taxonomic differentiation of these taxa. Methods DNA from 89 individuals from all known locations of Aquilegia across Sardinia was analysed by means of amplified fragment length polymorphism (AFLP) markers. Both principal co-ordinates analysis (PCoA) and Bayesian clustering analyses were used to determine the spatial genetic structure irrespective of any taxonomic affiliation. Historical effects of gene flow and genetic drift were assessed by checking for the existence of isolation-by-distance patterns. Key Results STRUCTURE and PCoA analyses revealed a pattern of genetic variation geographically structured into four spatial genetic groups. No migration–drift equilibrium was detected for Aquilegia in Sardinia, when analysed either as a whole or in individual groups. The scenario approached a Case III pattern sensu Hutchinson and Templeton, which is associated with extreme isolation conditions where genetic drift has historically played a dominant role over gene flow. Conclusions The pattern of genetic variation of Sardinian taxa of Aquilegia indicates that genetic drift has been historically more influential than gene flow on population structure of Sardinian species of Aquilegia. Limited seed dispersal and divergent selection imposed by habitat conditions have been probably the main causes reinforcing post-Pleistocene geographical isolation of Aquilegia populations. The spatial genetic

  3. Deciphering The Role of Plankton Taxa in Particle Flux

    NASA Astrophysics Data System (ADS)

    Neuer, Susanne; Amacher, Jessica; DeMartini, Francesca; Wilson, Stephanie

    2015-04-01

    The sinking of phytoplankton derived particulate organic matter to the deep ocean constitutes an important removal process of atmospheric CO2 and is termed the biological carbon pump. Understanding the taxon specific connection between phytoplankton communities in the euphotic zone and their contribution to particle flux is a high priority in current oceanographic research and provides a basis to evaluate how carbon export might change in a future ocean. Here we present results from DNA-based molecular studies that investigate the taxonomic composition of cyanobacterial and protist communities retrieved from shallow particle traps in comparison to those living in the euphotic zone. This research has been mainly carried out in the Sargasso Sea at the Bermuda Atlantic Time-series Study site (BATS). Trap material collected at this oligotrophic ocean site reveals a surprisingly high diversity of small, non-mineral ballasted taxa, some of which are over-represented compared to the euphotic zone communities. But the majority of clones in the traps belong to mostly heterotrophic protist taxa. By analyzing the fingerprints of prey DNA in guts and fecal pellets of dominant zooplankton grazers we find that there is a close link between prey utilization and the recovery of those taxa in the traps, showing the importance of fecal pellets in packaging and mediating their flux out of the euphotic zone.

  4. Interaction between arthropod filiform hairs in a fluid environment.

    PubMed

    Cummins, Bree; Gedeon, Tomás; Klapper, Isaac; Cortez, Ricardo

    2007-07-21

    Many arthropods use filiform hairs as mechanoreceptors to detect air motion. In common house crickets (Acheta domestica) the hairs cover two antenna-like appendages called cerci at the rear of the abdomen. The biomechanical stimulus-response properties of individual filiform hairs have been investigated and modeled extensively in several earlier studies. However, only a few previous studies have considered viscosity-mediated coupling between pairs of hairs, and only in particular configurations. Here, we present a model capable of calculating hair-to-hair coupling in arbitrary configurations. We simulate the coupled motion of a small group of mechanosensory hairs on a cylindrical section of cercus. We have found that the coupling effects are non-negligible, and likely constrain the operational characteristics of the cercal sensory array. PMID:17434184

  5. Identification of a Flavivirus Sequence in a Marine Arthropod

    PubMed Central

    Conway, Michael J.

    2015-01-01

    Phylogenetic analysis has yet to uncover the early origins of flaviviruses. In this study, I mined a database of expressed sequence tags in order to discover novel flavivirus sequences. Flavivirus sequences were identified in a pool of mRNA extracted from the sea spider Endeis spinosa (Pycnogonida, Pantopoda). Reconstruction of the translated sequences and BLAST analysis matched the sequence to the flavivirus NS5 gene. Additional sequences corresponding to envelope and the NS5 MTase domain were also identified. Phylogenetic analysis of homologous NS5 sequences revealed that Endeis spinosa NS5 (ESNS5) is likely related to classical insect-specific flaviviruses. It is unclear if ESNS5 represents genetic material from an active viral infection or an integrated viral genome. These data raise the possibility that classical insect-specific flaviviruses and perhaps medically relevant flaviviruses, evolved from progenitors that infected marine arthropods. PMID:26717191

  6. Comparison of Arthropod Prey of Red-Cockaded Woodpeckers on the Boles of Longleaf and Loblolly Pines

    SciTech Connect

    Horn, S.; Hanula, J.

    2002-01-01

    Use of knockdown insecticides to sample arthropods on longleaf and loblolly pine to determine which harbored the greater abundance of potential prey. Alterations of longleaf pine bark surface to determine whether bark structure may affect arthropods residing on a tree's bole. Recovery revealed fewer arthropods from scraped trees. Results suggest the bark structure and not the chemical nature of the bark is responsible for differences in arthropod abundance and biomass. Retaining or restoring longleaf pine in red-cockaded woodpecker habitats should increase arthropod availability for this endangered bird and other back-foraging species.

  7. Effects of persistent insecticides on beneficial soil arthropod in conventional fields compared to organic fields, puducherry.

    PubMed

    Anbarashan, Padmavathy; Gopalswamy, Poyyamoli

    2013-07-15

    The usage of synthetic fertilizers/insecticides in conventional farming has dramatically increased over the past decades. The aim of the study was to compare the effects of bio-pesticides and insecticides/pesticides on selected beneficial non targeted arthropods. Orders Collembola, Arachinida/Opiliones, Oribatida and Coleoptera were the main groups of arthropods found in the organic fields and Coleoptera, Oribatida, Gamasida and Collembola in conventional fields. Pesticides/insecticides had a significant effect on non-targeted arthropods order- Collembola, Arachinida/Opiliones, Hymenoptera and Thysonoptera were suppressed after pesticides/insecticides spraying. Bio-insecticides in organic fields had a non-significant effect on non targeted species and they started to increase in abundance after 7 days of spraying, whereas insecticide treatment in conventional fields had a significant long-term effect on non targeted arthropods and short term effect on pests/insects, it started to increase after 21 days of the spraying. These results indicate that insecticide treatment kept non targeted arthropods at low abundance. In conclusion, organic farming does not significantly affected the beneficial-non targeted arthropods biodiversity, whereas preventive insecticide application in conventional fields had significant negative effects on beneficial non targeted arthropods. Therefore, conventional farmers should restrict insecticide applications, unless pest densities reach the thresholds and more desirably can switch to organic farming practices. PMID:24505991

  8. Arthropod abundance and seasonal bird use of bottomland forest harvest gaps.

    SciTech Connect

    Moorman, Christopher, E.; Bowen, Liessa T.; Kilgo, John, C.; Hanula, James, L.; Horn, Scott; Ulyshen, Michael, D.

    2012-03-01

    We investigated the influence of arthropod abundance and vegetation structure on shifts in avian use of canopy gap, gap edge, and surrounding forest understory in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. We compared captures of foliage-gleaning birds among locations during four periods (spring migration, breeding, post-breeding, and fall migration). Foliage arthropod densities were greatest in the forest understory in all four seasons, but understory vegetation density was greatest in gaps. Foliage-gleaning bird abundance was positively associated with foliage-dwelling arthropods during the breeding (F = 18.5, P < 0.001) and post-breeding periods (F = 9.4, P = 0.004), and negatively associated with foliage-dwelling arthropods during fall migration (F = 5.4, P = 0.03). Relationships between birds and arthropods were inconsistent, but the arthropod prey base seemed to be least important during migratory periods. Conversely, bird captures were positively correlated with understory vegetation density during all four periods (P < 0.001). Our study suggests high bird abundance associated with canopy gaps during the non-breeding period resulted less from high arthropod food resource availability than from complex understory and midstory vegetation structure.

  9. New insights on arthropod toxins that potentiate erectile function.

    PubMed

    Nunes, Kenia P; Torres, Fernanda S; Borges, Marcia H; Matavel, Alessandra; Pimenta, Adriano M C; De Lima, Maria E

    2013-07-01

    The use of natural substances for the treatment of diseases or injuries is an ancient practice of many cultures. According to folklore, natural aphrodisiacs may help to raise libido and increase desire. The supposed aphrodisiacs mainly include a plethora of preparations of plants, among other substances. However, the real boundary between myth and reality has not been established yet in most cases and such boundaries must be drawn by scientific methods. A growing interest of the scientific community has been focused on animal venoms, especially those from arthropods, i.e. spiders and scorpions, which cause priapism, a prolonged and painful erection. This review highlights the studies that have been performed with venoms and toxins from arthropods known to cause priapism, among other toxic symptoms, pointing out some pharmacological approaches for better understanding this effect. To date, the venom of some spiders, mainly Phoneutria nigriventer, and scorpions, such as the yellow South American scorpion Tityus serrulatus, among others, have been known to cause priapism. Since erectile dysfunction (ED) is a growing health problem in the world, more common in patients with vascular diseases as diabetes and hypertension, the use of animal venoms and toxins as pharmacological tools could not only shed light to the mechanisms involved in erectile function, but also represent a possible model for new drugs to treat ED. Unfortunately, attempts to correlate the structure of those priapism-related toxins were unfruitful. Such difficulties lie firstly on the poor data concerning purified priapism-related toxins, instead of whole venoms and/or semi-purified fractions, and secondly, on the scarce available primary sequences and structural data, mainly from spider toxins. It has been shown that all these toxins modify the sodium (Na(+)) channel activity, mostly slowing down its inactivation current. Improving the knowledge on the tertiary structure of these toxins could provide

  10. Phenoptosis in arthropods and immortality of social insects.

    PubMed

    Kartsev, V M

    2014-10-01

    In general, there are no drastic differences in phenoptosis patterns in plant and animal organisms. However, there are some specific features characteristic for insects and other arthropods: 1) their development includes metamorphosis with different biochemical laws at consecutive developmental stages; 2) arthropods can reduce or stop development and aging when in a state of diapause or temporal cold immobility; 3) their life cycle often correlates with seasonal changes of surroundings; 4) polymorphism is widespread - conspecifics differ by their lifespans and phenoptosis features; 5) lifespan-related sexual dimorphism is common; 6) significant situational plasticity of life cycle organization is an important feature; for example, the German wasp (Paravespula germanica) is obligatorily univoltine in the temperate zone, while in tropical regions its lifespan increases and leads to repeated reproduction; 7) life cycles of closely related species may differ significantly, for example, in contrast to German wasp, some tropical hornets (Vespa) have only one reproduction period. Surprisingly, many insect species have been shown to be subjected to gradual aging and phenoptosis, like the highest mammals. However, queens of social insects and some long-lived arachnids can apparently be considered non-aging organisms. In some species, lifespan is limited to one season, while others live much longer or shorter. Cases of one-time reproduction are rather rare. Aphagia is common in insects (over 10,000 species). Cannibalism is an important mortality factor in insects as well as in spiders. In social insects, which exist only in colonies (families), the lifetime of a colony can be virtually unlimited. However, in case of some species the developmental cycle and death of a colony after its completion are predetermined. Most likely, natural selection in insects does not lengthen individual lifespan, but favors increase in reproduction efficiency based on fast succession of

  11. Decoding the ubiquitin-mediated pathway of arthropod disease vectors.

    PubMed

    Choy, Anthony; Severo, Maiara S; Sun, Ruobai; Girke, Thomas; Gillespie, Joseph J; Pedra, Joao H F

    2013-01-01

    Protein regulation by ubiquitin has been extensively described in model organisms. However, characterization of the ubiquitin machinery in disease vectors remains mostly unknown. This fundamental gap in knowledge presents a concern because new therapeutics are needed to control vector-borne diseases, and targeting the ubiquitin machinery as a means for disease intervention has been already adopted in the clinic. In this study, we employed a bioinformatics approach to uncover the ubiquitin-mediated pathway in the genomes of Anopheles gambiae, Aedes aegypti, Culex quinquefasciatus, Ixodes scapularis, Pediculus humanus and Rhodnius prolixus. We observed that (1) disease vectors encode a lower percentage of ubiquitin-related genes when compared to Drosophila melanogaster, Mus musculus and Homo sapiens but not Saccharomyces cerevisiae; (2) overall, there are more proteins categorized as E3 ubiquitin ligases when compared to E2-conjugating or E1-activating enzymes; (3) the ubiquitin machinery within the three mosquito genomes is highly similar; (4) ubiquitin genes are more than doubled in the Chagas disease vector (R. prolixus) when compared to other arthropod vectors; (5) the deer tick I. scapularis and the body louse (P. humanus) genomes carry low numbers of E1-activating enzymes and HECT-type E3 ubiquitin ligases; (6) R. prolixus have low numbers of RING-type E3 ubiquitin ligases; and (7) C. quinquefasciatus present elevated numbers of predicted F-box E3 ubiquitin ligases, JAB and UCH deubiquitinases. Taken together, these findings provide novel opportunities to study the interaction between a pathogen and an arthropod vector. PMID:24205097

  12. The first complete mitochondrial genome sequences of Amblypygi (Chelicerata: Arachnida) reveal conservation of the ancestral arthropod gene order.

    PubMed

    Fahrein, Kathrin; Masta, Susan E; Podsiadlowski, Lars

    2009-05-01

    Amblypygi (whip spiders) are terrestrial chelicerates inhabiting the subtropics and tropics. In morphological and rRNA-based phylogenetic analyses, Amblypygi cluster with Uropygi (whip scorpions) and Araneae (spiders) to form the taxon Tetrapulmonata, but there is controversy regarding the interrelationship of these three taxa. Mitochondrial genomes provide an additional large data set of phylogenetic information (sequences, gene order, RNA secondary structure), but in arachnids, mitochondrial genome data are missing for some of the major orders. In the course of an ongoing project concerning arachnid mitochondrial genomics, we present the first two complete mitochondrial genomes from Amblypygi. Both genomes were found to be typical circular duplex DNA molecules with all 37 genes usually present in bilaterian mitochondrial genomes. In both species, gene order is identical to that of Limulus polyphemus (Xiphosura), which is assumed to reflect the putative arthropod ground pattern. All tRNA gene sequences have the potential to fold into structures that are typical of metazoan mitochondrial tRNAs, except for tRNA-Ala, which lacks the D arm in both amblypygids, suggesting the loss of this feature early in amblypygid evolution. Phylogenetic analysis resulted in weak support for Uropygi being the sister group of Amblypygi. PMID:19448726

  13. Future rainfall patterns will reduce arthropod abundance in model arable agroecosystems with different soil types

    NASA Astrophysics Data System (ADS)

    Zaller, Johann; Simmer, Laura; Tabi Tataw, James; Formayer, Herbert; Hösch, Johannes; Baumgarten, Andreas

    2013-04-01

    Climate change scenarios for eastern Austria predict a seasonal shift in precipitation patterns with fewer but heavier rainfall events and longer drought periods during the growing season and more precipitation during winter. This is expected to alter arthropods living in natural and agricultural ecosystems with consequences for several ecosystem functions and services. In order to better understand the effects of future rainfall patterns on aboveground arthropods inhabiting an agroecosystem, we conducted an experiment where we simulated rainfall patterns in model arable systems with three different soil types. Experiments were conducted in winter wheat cultivated in a lysimeter facility near Vienna, Austria, where three different soil types (calcaric phaeozem, calcic chernozem and gleyic phaeozem) were subjected to long-term current vs. predicted rainfall patterns according to regionalized climate change projections for 2071-2100. Aboveground arthropods were assessed by suction sampling in April, May and June 2012. We found significant differences in mean total arthropod abundances between the sampling dates with 20 ± 2 m-2, 90 ± 20 m-2 and 289 ± 54 m-2 in April, May and June, respectively. Across all three sampling dates, future rainfall patterns significantly reduced the abundance of Araneae (-43%), Auchenorrhyncha (-39%), Coleoptera (-48%), Carabidae (-41%), Chrysomelidae (-64%), Collembola (-58%), Diptera (-75%) and Neuroptera (-73%). Generally, different soil types had no effect on the abundance of arthropods. The diversity of arthropod communities was unaffected by rainfall patterns or soil types. Correlation analyses of arthropod abundances with crop biomass, weed density and abundance suggest that rainfall effects indirectly affected arthropods via changes on crops and weeds. In conclusion, these results show that future rainfall patterns will have detrimental effects on the abundance of a variety of aboveground arthropods in winter wheat with potential

  14. Grassland Arthropods Are Controlled by Direct and Indirect Interactions with Cattle but Are Largely Unaffected by Plant Provenance

    PubMed Central

    Farrell, Kelly Anne; Harpole, W. Stanley; Stein, Claudia; Suding, Katharine N.; Borer, Elizabeth T.

    2015-01-01

    Cattle grazing and invasion by non-native plant species are globally-ubiquitous changes occurring to plant communities that are likely to reverberate through whole food webs. We used a manipulative field experiment to quantify how arthropod community structure differed in native and non-native California grassland communities in the presence and absence of grazing. The arthropod community was strongly affected by cattle grazing: the biovolume of herbivorous arthropods was 79% higher in grazed than ungrazed plots, whereas the biovolume of predatory arthropods was 13% higher in ungrazed plots. In plots where non-native grasses were grazed, arthropod biovolume increased, possibly in response to increased plant productivity or increased nutritional quality of rapidly-growing annual plants. Grazing may thus affect plant biomass both through the direct removal of biomass, and through arthropod-mediated impacts. We also expected the arthropod community to differ between native and non-native plant communities; surprisingly, arthropod richness and diversity did not vary consistently between these grass community types, although arthropod abundance was slightly higher in plots with native and ungrazed grasses. These results suggest that whereas cattle grazing affects the arthropod community via direct and indirect pathways, arthropod community changes commonly associated with non-native plant invasions may not be due to the identity or dominance of the invasive species in those systems, but to accompanying changes in plant traits or functional group composition, not seen in this experiment because of the similarity of the plant communities. PMID:26158494

  15. Unprecedented genomic diversity of RNA viruses in arthropods reveals the ancestry of negative-sense RNA viruses

    PubMed Central

    Li, Ci-Xiu; Shi, Mang; Tian, Jun-Hua; Lin, Xian-Dan; Kang, Yan-Jun; Chen, Liang-Jun; Qin, Xin-Cheng; Xu, Jianguo; Holmes, Edward C; Zhang, Yong-Zhen

    2015-01-01

    Although arthropods are important viral vectors, the biodiversity of arthropod viruses, as well as the role that arthropods have played in viral origins and evolution, is unclear. Through RNA sequencing of 70 arthropod species we discovered 112 novel viruses that appear to be ancestral to much of the documented genetic diversity of negative-sense RNA viruses, a number of which are also present as endogenous genomic copies. With this greatly enriched diversity we revealed that arthropods contain viruses that fall basal to major virus groups, including the vertebrate-specific arenaviruses, filoviruses, hantaviruses, influenza viruses, lyssaviruses, and paramyxoviruses. We similarly documented a remarkable diversity of genome structures in arthropod viruses, including a putative circular form, that sheds new light on the evolution of genome organization. Hence, arthropods are a major reservoir of viral genetic diversity and have likely been central to viral evolution. DOI: http://dx.doi.org/10.7554/eLife.05378.001 PMID:25633976

  16. Simulating small-scale climate change effects-lessons from a short-term field manipulation experiment on grassland arthropods.

    PubMed

    Buchholz, Sascha; Rolfsmeyer, Dorothee; Schirmel, Jens

    2013-10-01

    Climate change is expected to cause major consequences on biodiversity. Understanding species-specific reactions, such as species shifts, species declines, and changes in population dynamics is a key issue to quantify large-scale impacts of climate change on biotic communities. As it is often impossible or at least impracticable to conduct large-scale experiments on biotic responses to climate change, studies at a smaller scale may be a useful alternative. In our study, we therefore tested responses of grassland arthropods (carabid beetles, spiders, grasshoppers) to simulated climate change in terms of species activity densities and diversity. We conducted a controlled field experiment by changing water and microclimatic conditions at a small scale (16 m(2) ). Roof constructions were used to increase drought-like conditions, whereas water supply was enhanced by irrigation. In all, 2 038 carabid beetles (36 species), 4 893 spiders (65 species), and 303 Orthoptera (4 species) were caught using pitfall traps from May to August, 2010. During our experiment, we created an artificial small-scale climate change; and statistics revealed that these changes had short-term effects on the total number of individuals and Simpson diversity of the studied arthropod groups. Moreover, our results showed that certain species might react very quickly to climate change in terms of activity densities, which in turn might influence diversity due to shifts in abundance patterns. Finally, we devised methodological improvements that may further enhance the validity of future studies. PMID:23956202

  17. Mid-Cretaceous charred fossil flowers reveal direct observation of arthropod feeding strategies.

    PubMed

    Hartkopf-Fröder, Christoph; Rust, Jes; Wappler, Torsten; Friis, Else Marie; Viehofen, Agnes

    2012-04-23

    Although plant-arthropod relationships underpin the dramatic rise in diversity and ecological dominance of flowering plants and their associated arthropods, direct observations of such interactions in the fossil record are rare, as these ephemeral moments are difficult to preserve. Three-dimensionally preserved charred remains of Chloranthistemon flowers from the Late Albian to Early Cenomanian of Germany preserve scales of mosquitoes and an oribatid mite with mouthparts inserted into the pollen sac. Mosquitoes, which today are frequent nectar feeders, and the mite were feeding on pollen at the time wildfire consumed the flowers. These findings document directly arthropod feeding strategies and their role in decomposition. PMID:21900310

  18. Mid-Cretaceous charred fossil flowers reveal direct observation of arthropod feeding strategies

    PubMed Central

    Hartkopf-Fröder, Christoph; Rust, Jes; Wappler, Torsten; Friis, Else Marie; Viehofen, Agnes

    2012-01-01

    Although plant–arthropod relationships underpin the dramatic rise in diversity and ecological dominance of flowering plants and their associated arthropods, direct observations of such interactions in the fossil record are rare, as these ephemeral moments are difficult to preserve. Three-dimensionally preserved charred remains of Chloranthistemon flowers from the Late Albian to Early Cenomanian of Germany preserve scales of mosquitoes and an oribatid mite with mouthparts inserted into the pollen sac. Mosquitoes, which today are frequent nectar feeders, and the mite were feeding on pollen at the time wildfire consumed the flowers. These findings document directly arthropod feeding strategies and their role in decomposition. PMID:21900310

  19. Changes in soil temperature during prescribed burns impact local arthropod communities

    NASA Astrophysics Data System (ADS)

    Verble-Pearson, Robin; Perry, Gad

    2016-04-01

    As wildfires increase in severity and intensity globally, the development of methods to assess their effects on soils is of increasing importance. We examined soil arthropod communities in the southern United States and estimated their abundance, species richness, and composition in areas recently impacted by prescribed burns. In addition, we placed thermal probes in soils and correlated soil temperatures to arthropod responses. Longer fire residence times resulted in greater soil heating which resulted in decreases in arthropod abundance and species richness and shifts in species composition. We believe that these results may be useful in developing tools to assess fire effects on soil systems.

  20. An assessment of arthropod prey resources at Nakula Natural Area Reserve, a potential site of reintroduction for Kiwikiu (Pseudonestor xanthophrys) and Maui `Alauahio (Parareomyza montana).

    USGS Publications Warehouse

    Banko, Paul C.; Peck, Robert W.; Cappadonna, Justin; Steele, Claire; Leonard, David L.; Mounce, Hanna L.; Becker, Dusti; Swinnerton, Kirsty

    2015-01-01

    ), which comprised 90% of all prey items for 50 adult birds and 98% of all prey for two nestlings. Caterpillars were also the most important prey for Maui ‘alauahio (43% for 104 adult birds) although spiders (Araneae, 16%), beetles (12%) and true bugs, planthoppers and psyllids (Hemiptera; 12%) were also important. Caterpillars were generally the most abundant type of arthropod in the foliage of koa and ‘ōhi‘a, although spiders, beetles and hemipterans were also common. Total arthropod biomass and caterpillar biomass at Nakula was as great, or greater, than that observed at Hanawi and Waikamoi per unit of foliage of both koa and ‘ōhi‘a. Spiders generally dominated the bark fauna on both koa and ‘ōhi‘a at all sites although isopods (Isopoda), millipedes (Myriapoda: Millipeda) and lacewings (Neuroptera) were also abundant at Waikamoi and Hanawi. Total arthropod biomass on bark, as well as the biomass of several individual taxa, was significantly lower at Nakula than the other sites. Our measurement of the density of beetle exit holes in dead koa branches found no difference between Nakula and Waikamoi. Finally, no difference existed in the abundance of arthropods (primarily caterpillars and moth pupae) within ‘ākala stems among sites. With the exception of bark surfaces, our results suggest that the arthropod prey base for birds on primary foraging substrates at Nakula is similar to that found at two sites within the current range of kiwikiu and Maui ‘alauahio. However, our results should be viewed with caution because they are limited to the scale of individual branch, tree, or ‘ākala stem. To complete the assessment, our results should be scaled up to the landscape level by determining the density of each substrate within each site. Key arthropod prey of kiwikiu and Maui ‘alauahio are available at Nakula and, as habitat restoration continues, food abundance should increase to the point at which populations of these birds can be supported.

  1. Three-dimensional Magnetic Resonance Imaging of fossils across taxa

    NASA Astrophysics Data System (ADS)

    Mietchen, D.; Aberhan, M.; Manz, B.; Hampe, O.; Mohr, B.; Neumann, C.; Volke, F.

    2007-08-01

    The visibility of life forms in the fossil record is largely determined by the extent to which they were mineralised at the time of their death. In addition to mineral structures, many fossils nonetheless contain detectable amounts of residual water or organic molecules, the analysis of which has become an integral part of current palaeontological research. The methods available for this sort of investigations, though, typically require dissolution or ionisation of the fossil sample or parts thereof, which is an issue with rare taxa and outstanding materials like pathological or type specimens. In such cases, non-destructive techniques could provide an interesting methodological alternative. While Computed Tomography has long been used to study palaeontological specimens, a number of complementary approaches have recently gained ground. These include Magnetic Resonance Imaging (MRI) which had previously been employed to obtain three-dimensional images of pathological belemnites non-invasively on the basis of intrinsic contrast. The present study was undertaken to investigate whether 1H MRI can likewise provide anatomical information about non-pathological belemnites and specimens of other fossil taxa. To this end, three-dimensional MR image series were acquired from intact non-pathological invertebrate, vertebrate and plant fossils. At routine voxel resolutions in the range of several dozens to some hundreds of micrometers, these images reveal a host of anatomical details and thus highlight the potential of MR techniques to effectively complement existing methodological approaches for palaeontological investigations in a wide range of taxa. As for the origin of the MR signal, relaxation and diffusion measurements as well as 1H and 13C MR spectra acquired from a belemnite suggest intracrystalline water or hydroxyl groups, rather than organic residues.

  2. Three-dimensional Magnetic Resonance Imaging of fossils across taxa

    NASA Astrophysics Data System (ADS)

    Mietchen, D.; Aberhan, M.; Manz, B.; Hampe, O.; Mohr, B.; Neumann, C.; Volke, F.

    2008-01-01

    The frequency of life forms in the fossil record is largely determined by the extent to which they were mineralised at the time of their death. In addition to mineral structures, many fossils nonetheless contain detectable amounts of residual water or organic molecules, the analysis of which has become an integral part of current palaeontological research. The methods available for this sort of investigations, though, typically require dissolution or ionisation of the fossil sample or parts thereof, which is an issue with rare taxa and outstanding materials like pathological or type specimens. In such cases, non-destructive techniques could provide a valuable methodological alternative. While Computed Tomography has long been used to study palaeontological specimens, a number of complementary approaches have recently gained ground. These include Magnetic Resonance Imaging (MRI) which had previously been employed to obtain three-dimensional images of pathological belemnites non-invasively on the basis of intrinsic contrast. The present study was undertaken to investigate whether 1H MRI can likewise provide anatomical information about non-pathological belemnites and specimens of other fossil taxa. To this end, three-dimensional MR image series were acquired from intact non-pathological invertebrate, vertebrate and plant fossils. At routine voxel resolutions in the range of several dozens to some hundreds of micrometers, these images reveal a host of anatomical details and thus highlight the potential of MR techniques to effectively complement existing methodological approaches for palaeontological investigations in a wide range of taxa. As for the origin of the MR signal, relaxation and diffusion measurements as well as 1H and 13C MR spectra acquired from a belemnite suggest intracrystalline water or hydroxyl groups, rather than organic residues.

  3. Nuclear DNA Content Variation among Central European Koeleria Taxa

    PubMed Central

    PECINKA, ALES; SUCHÁNKOVÁ, PAVLA; LYSAK, MARTIN A.; TRÁVNÍČEK, BOHUMIL; DOLEŽEL, JAROSLAV

    2006-01-01

    • Background and Aims Polyploidization plays an important role in the evolution of many plant genera, including Koeleria. The knowledge of ploidy, chromosome number and genome size may enable correct taxonomic treatment when other features are insufficient as in Koeleria. Therefore, these characteristics and their variability were determined for populations of six central European Koeleria taxa. • Methods Chromosome number analysis was performed by squashing root meristems, and ploidy and 2C nuclear DNA content were estimated by flow cytometry. • Key Results Three diploids (K. glauca, K. macrantha var. macrantha and var. pseudoglauca), one tetraploid (K. macrantha var. majoriflora), one decaploid (K. pyramidata) and one dodecaploid (K. tristis) were found. The 2C nuclear DNA content of the diploids ranged from 4·85 to 5·20 pg. The 2C DNA contents of tetraploid, decaploid and dodecaploid taxa were 9·31 pg, 22·89 pg and 29·23 pg, respectively. The DNA content of polyploids within the K. macrantha aggregate (i.e. within K. macrantha and K. pyramidata) was smaller than the expected multiple of the diploid genome (K. macrantha var. macrantha). Geography-correlated variation of DNA content was found for some taxa. Czech populations of K. macrantha var. majoriflora had a 5·06 % smaller genome than the Slovak ones. An isolated eastern Slovakian population of K. tristis revealed 8·04 % less DNA than populations from central Slovakia. In central and north-west Bohemia, diploid and tetraploid cytotypes of K. macrantha were sympatric; east from this region diploid populations, and towards the west tetraploid populations were dominant. • Conclusions Remarkable intra-specific inter-population differences in nuclear DNA content were found between Bohemian and Pannonian populations of Koeleria macrantha var. majoriflora and between geographically isolated central and eastern Slovakian populations of K. tristis. These differences occur over a relatively small

  4. Biological communities at the Florida Escarpment resemble hydrothermal vent taxa

    USGS Publications Warehouse

    Paull, C.K.; Hecker, Barbara; Commeau, R.; Freeman-Lynde, R. P.; Neumann, C.; Corso, W.P.; Golubic, S.; Hook, J.E.; Sikes, E.; Curray, J.

    1984-01-01

    Dense biological communities of large epifaunal taxa similar to those found along ridge crest vents at the East Pacific Rise were discovered in the abyssal Gulf of Mexico. These assemblages occur on a passive continental margin at the base of the Florida Escarpment, the interface between the relatively impermeable hemipelagic clays of the distal Mississippi Fan and the jointed Cretaceous limestone of the Florida Platform. The fauna apparently is nourished by sulfide rich hypersaline waters seeping out at near ambient temperatures onto the sea floor.

  5. Analysing body condition: mass, volume or density?

    PubMed

    Moya-Laraño, Jordi; Macías-Ordóñez, Rogelio; Blanckenhorn, Wolf U; Fernández-Montraveta, Carmen

    2008-11-01

    1. Body condition (defined as the relative amount of energy reserves in the body) is an animal trait with strong ecological implications. In some animal taxa (e.g. arthropods), the external volume of the body part in which most nutrients are stored (e.g. abdomen) is used interchangeably with body mass to estimate body condition, making the implicit assumption that abdomen residual volume is a good surrogate of residual mass. However, the degree of correlation between these two measures should largely depend on the density of the nutrients stored. 2. We simulated two food-supplemented experimental groups of animals, each storing a slightly different amount of lipids either in their abdomens or in their entire bodies, and explored (i) how different estimates of condition were able to detect fixed differences between the groups; and (ii) how the amount of lipids stored could affect the outcome of non-intrusive measures of condition on a dichotomous variable (e.g. survival, mating success). We found that density body condition (body mass statistically controlled for structural body size and body volume) has much greater power to detect differences between experimental groups or effects on binary response variables than do classic mass/size or volume/size condition indices. 3. Using data on Lycosa tarantula (L.), a burrowing wolf spider, we report dramatic differences among these three indices in their ability to detect sex differences in the effect of feeding treatment on body condition at maturity. In particular, a plot of residual mass against residual volume reflecting nutrient density suggests that poorly fed spiders are nutritionally unbalanced, since well-fed spiders invest in nutrients of very different density. 4. Furthermore, using data on Scathophaga stercoraria (L.), the yellow dung fly, we found that an index of density condition was better at distinguishing condition differences among three populations than were mass or volume condition estimates alone. 5

  6. Introduction to symposium: Arthropods and wildlife conservation: synergy in complex biological systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The symposium will discuss the effects of arthropods and other stressors on wildlife conservation programs. Speakers with affiliations in wildlife biology, parasitology and entomology will be included in the program. Research of national and international interest will be presented....

  7. Implication of haematophagous arthropod salivary proteins in host-vector interactions

    PubMed Central

    2011-01-01

    The saliva of haematophagous arthropods contains an array of anti-haemostatic, anti-inflammatory and immunomodulatory molecules that contribute to the success of the blood meal. The saliva of haematophagous arthropods is also involved in the transmission and the establishment of pathogens in the host and in allergic responses. This survey provides a comprehensive overview of the pharmacological activity and immunogenic properties of the main salivary proteins characterised in various haematophagous arthropod species. The potential biological and epidemiological applications of these immunogenic salivary molecules will be discussed with an emphasis on their use as biomarkers of exposure to haematophagous arthropod bites or vaccine candidates that are liable to improve host protection against vector-borne diseases. PMID:21951834

  8. Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic

    PubMed Central

    Vannier, Jean; Schoenemann, Brigitte; Gillot, Thomas; Charbonnier, Sylvain; Clarkson, Euan

    2016-01-01

    Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized. Here, we reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France. This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment. PMID:26785293

  9. Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic.

    PubMed

    Vannier, Jean; Schoenemann, Brigitte; Gillot, Thomas; Charbonnier, Sylvain; Clarkson, Euan

    2016-01-01

    Vision has revolutionized the way animals explore their environment and interact with each other and rapidly became a major driving force in animal evolution. However, direct evidence of how ancient animals could perceive their environment is extremely difficult to obtain because internal eye structures are almost never fossilized. Here, we reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France. This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies. Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment. PMID:26785293

  10. Bison grazing increases arthropod abundance and diversity in a tallgrass prairie.

    PubMed

    Moran, Matthew D

    2014-10-01

    How grazing-induced ecosystem changes by ungulates indirectly affect other consumers is a question of great interest. I investigated the effect of grazing by American Bison (Bos bison L.) on an arthropod community in tallgrass prairie. Grazing increased the abundance of arthropods, an increase that was present in both herbivorous and carnivorous assemblages, but not in detritivores. The increase in herbivores and reduction in plant biomass from grazing resulted in an arthropod herbivore load almost three times higher in grazed plots compared with controls. Among herbivores, the sap-feeding insect guild was dramatically more abundant, while chewing herbivores were not affected. Herbivorous and carnivorous arthropod richness was higher in grazed plots, although the response was strongest among herbivores. Arthropod abundance on individual grasses and forbs was significantly higher in grazed areas, while plant type had no effect on abundance, indicating that the change was ecosystem-wide and not simply in response to a reduction in grass biomass from grazing. The response of arthropods to grazing was strongest in the early part of the growing season. Published research shows that ungulate grazing, although decreasing available biomass to other consumers, enhances plant quality by increasing nitrogen level in plants. The arthropod results of this study suggest higher plant quality outweighs the potential negative competitive effects of plant biomass removal, although other activities of bison could not be ruled out as the causative mechanism. Because arthropods are extremely abundant organisms in grasslands and a food source for other consumers, bison may represent valuable management tools for maintaining biodiversity. PMID:25198902

  11. Nematode and Arthropod Genomes Provide New Insights into the Evolution of Class 2 B1 GPCRs

    PubMed Central

    Cardoso, João C. R.; Félix, Rute C.; Power, Deborah M.

    2014-01-01

    Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes. PMID:24651821

  12. Stable isotopic studies on chitin. III. The D/H and 18O/ 16O ratios in arthropod chitin

    NASA Astrophysics Data System (ADS)

    Schimmelmann, Arndt; DeNiro, Michael J.

    1986-07-01

    Stable hydrogen and oxygen isotope ratios are presented for carbon-bound hydrogen and for oxygen in chitin-derived substrates from 57 arthropod species collected in 50 different locations or grown under controlled conditions in the laboratory. No systematic isotopic differences were found among Insecta, Crustacea, and Merostomata. The determination of infra- and interindividual isotopic variabilities in a lobster and among individuals of crustacean populations yielded small variances of about ±3 per mil for δD values and ±0.3 per mil for δ 18O values. Molting stage and sex of crustaceans showed no systematic effects on isotopic composition. The δD and δ 18O values of ambient water showed only weak correlations with the respective δ values of chitin-derived substrates. Positive correlation was observed between δD values and trophic level. No temperature effects on δ 18O and δD values from marine crustaceans were found that exceed the natural isotopic noise level. Taken together, these observations indicate that reconstruction of water isotopic composition from arthropod chitin δD and δ 18O values will require specific information about the habits and habitats of the species involved in the analysis.

  13. Methane-fed microbial microcosms show differential community dynamics and pinpoint taxa involved in communal response

    PubMed Central

    Oshkin, Igor Y; Beck, David AC; Lamb, Andrew E; Tchesnokova, Veronika; Benuska, Gabrielle; McTaggart, Tami L; Kalyuzhnaya, Marina G; Dedysh, Svetlana N; Lidstrom, Mary E; Chistoserdova, Ludmila

    2015-01-01

    We report observations on the dynamics of bacterial communities in response to methane stimulus in laboratory microcosm incubations prepared with lake sediment samples. We first measured taxonomic compositions of long-term enrichment cultures and determined that, although dominated by Methylococcaceae types, these cultures also contained accompanying types belonging to a limited number of bacterial taxa, methylotrophs and non-methylotrophs. We then followed the short-term community dynamics, in two oxygen tension regimens (150 μM and 15 μM), observing rapid loss of species diversity. In all microcosms, a single type of Methylobacter represented the major methane-oxidizing partner. The accompanying members of the communities revealed different trajectories in response to different oxygen tensions, with Methylotenera species being the early responders to methane stimulus under both conditions. The communities in both conditions were convergent in terms of their assemblage, suggesting selection for specific taxa. Our results support prior observations from metagenomics on distribution of carbon from methane among diverse bacterial populations and further suggest that communities are likely responsible for methane cycling, rather than a single type of microbe. PMID:25333464

  14. Methane-fed microbial microcosms show differential community dynamics and pinpoint taxa involved in communal response.

    PubMed

    Oshkin, Igor Y; Beck, David A C; Lamb, Andrew E; Tchesnokova, Veronika; Benuska, Gabrielle; McTaggart, Tami L; Kalyuzhnaya, Marina G; Dedysh, Svetlana N; Lidstrom, Mary E; Chistoserdova, Ludmila

    2015-05-01

    We report observations on the dynamics of bacterial communities in response to methane stimulus in laboratory microcosm incubations prepared with lake sediment samples. We first measured taxonomic compositions of long-term enrichment cultures and determined that, although dominated by Methylococcaceae types, these cultures also contained accompanying types belonging to a limited number of bacterial taxa, methylotrophs and non-methylotrophs. We then followed the short-term community dynamics, in two oxygen tension regimens (150 μM and 15 μM), observing rapid loss of species diversity. In all microcosms, a single type of Methylobacter represented the major methane-oxidizing partner. The accompanying members of the communities revealed different trajectories in response to different oxygen tensions, with Methylotenera species being the early responders to methane stimulus under both conditions. The communities in both conditions were convergent in terms of their assemblage, suggesting selection for specific taxa. Our results support prior observations from metagenomics on distribution of carbon from methane among diverse bacterial populations and further suggest that communities are likely responsible for methane cycling, rather than a single type of microbe. PMID:25333464

  15. Abundance and Diversity of Soil Arthropods in the Olive Grove Ecosystem

    PubMed Central

    Gonçalves, Maria Fátima; Pereira, José Alberto

    2012-01-01

    Arthropods are part of important functional groups in soil food webs. Recognizing these arthropods and understanding their function in the ecosystem as well as when they are active is essential to understanding their roles. In the present work, the abundance and diversity of soil arthropods is examined in olive groves in the northeast region of Portugal during the spring. Five classes of arthropods were found: Chilopoda, Malacostraca, Entognatha, Insecta, and Arachnida. Captures were numerically dominated by Collembola within Entognatha, representing 70.9% of total captures. Arachnida and Insecta classes represented about 20.4 and 9.0%, respectively. Among the predatory arthropods, the most representative groups were Araneae and Opiliones from Arachnida, and Formicidae, Carabidae, and Staphylinidae from Insecta. From the Formicidae family, Tetramorium semilaeve (Andre 1883), Tapinoma nigerrimum (Nylander 1856), and Crematogaster scutellaris (Olivier 1792) were the most representative ant species. Arthropods demonstrated preference during the day, with 74% of the total individuals recovered in this period, although richness and similarity were analogous during the day and night. PMID:22943295

  16. Community structure and nutrient content of canopy arthropods in clearcut and uncut forest ecosystems

    SciTech Connect

    Schowalter, T.D.; Webb, J.W.; Crossley, D.A. Jr.

    1981-08-01

    This paper describes differences in canopy arthropod community structure, major cation content, and calculated nutrient consumption between clearcut and undisturbed hardwood forest watersheds at Coweeta Hydrologic Laboratory, North Carolina, USA, during the first two growing seasons following cutting. Although canopy arthropod biomass was about 0.08% of foliage biomass on both watersheds, aphid mass increased 23-fold and ant mass increased 6-fold per unit foliage mass following cutting. These groups in general had lower nutrient concentrations than did chewing herbivores and predators. Arthropod K concentrations were 33% lower on the clearcut; Na, K, and Mg concentrations were 20 to 50% higher in 1978 than in 1977. Arthropod Mg and Ca concentrations, but not Na and K, were reduced significantly more by the greater effect of drought on the clearcut watershed. Consumption estimates based in part on consumption rates reported by others indicated increased nutrient translocation from foilage via arthropods following cutting. These data indicated that canopy arthropod responses to changes in nutrient availability following disturbance could have increased nutrient cycling rates and contributed to nutrient retention by the recovering ecosystem.

  17. Abundance and diversity of soil arthropods in the olive grove ecosystem.

    PubMed

    Gonçalves, Maria Fátima; Pereira, José Alberto

    2012-01-01

    Arthropods are part of important functional groups in soil food webs. Recognizing these arthropods and understanding their function in the ecosystem as well as when they are active is essential to understanding their roles. In the present work, the abundance and diversity of soil arthropods is examined in olive groves in the northeast region of Portugal during the spring. Five classes of arthropods were found: Chilopoda, Malacostraca, Entognatha, Insecta, and Arachnida. Captures were numerically dominated by Collembola within Entognatha, representing 70.9% of total captures. Arachnida and Insecta classes represented about 20.4 and 9.0%, respectively. Among the predatory arthropods, the most representative groups were Araneae and Opiliones from Arachnida, and Formicidae, Carabidae, and Staphylinidae from Insecta. From the Formicidae family, Tetramorium semilaeve (Andre 1883), Tapinoma nigerrimum (Nylander 1856), and Crematogaster scutellaris (Olivier 1792) were the most representative ant species. Arthropods demonstrated preference during the day, with 74% of the total individuals recovered in this period, although richness and similarity were analogous during the day and night. PMID:22943295

  18. Sensitivities of extant animal taxa to ocean acidification

    NASA Astrophysics Data System (ADS)

    Wittmann, Astrid C.; Pörtner, Hans-O.

    2013-11-01

    Anthropogenic CO2 emitted to the atmosphere is absorbed by the oceans, causing a progressive increase in ocean inorganic carbon concentrations and resulting in decreased water pH and calcium carbonate saturation. This phenomenon, called ocean acidification, is in addition to the warming effects of CO2 emissions. Ocean acidification has been reported to affect ocean biota, but the severity of this threat to ocean ecosystems (and humans depending on these ecosystems) is poorly understood. Here we evaluate the scale of this threat in the context of widely used representative concentration pathways (RCPs) by analysing the sensitivities of five animal taxa (corals, echinoderms, molluscs, crustaceans and fishes) to a wide range of CO2 concentrations. Corals, echinoderms and molluscs are more sensitive to RCP8.5 (936 ppm in 2100) than are crustaceans. Larval fishes may be even more sensitive than the lower invertebrates, but taxon sensitivity on evolutionary timescales remains obscure. The variety of responses within and between taxa, together with observations in mesocosms and palaeo-analogues, suggest that ocean acidification is a driver for substantial change in ocean ecosystems this century, potentially leading to long-term shifts in species composition.

  19. A microarray for assessing transcription from pelagic marine microbial taxa

    PubMed Central

    Shilova, Irina N; Robidart, Julie C; James Tripp, H; Turk-Kubo, Kendra; Wawrik, Boris; Post, Anton F; Thompson, Anne W; Ward, Bess; Hollibaugh, James T; Millard, Andy; Ostrowski, Martin; J Scanlan, David; Paerl, Ryan W; Stuart, Rhona; Zehr, Jonathan P

    2014-01-01

    Metagenomic approaches have revealed unprecedented genetic diversity within microbial communities across vast expanses of the world's oceans. Linking this genetic diversity with key metabolic and cellular activities of microbial assemblages is a fundamental challenge. Here we report on a collaborative effort to design MicroTOOLs (Microbiological Targets for Ocean Observing Laboratories), a high-density oligonucleotide microarray that targets functional genes of diverse taxa in pelagic and coastal marine microbial communities. MicroTOOLs integrates nucleotide sequence information from disparate data types: genomes, PCR-amplicons, metagenomes, and metatranscriptomes. It targets 19 400 unique sequences over 145 different genes that are relevant to stress responses and microbial metabolism across the three domains of life and viruses. MicroTOOLs was used in a proof-of-concept experiment that compared the functional responses of microbial communities following Fe and P enrichments of surface water samples from the North Pacific Subtropical Gyre. We detected transcription of 68% of the gene targets across major taxonomic groups, and the pattern of transcription indicated relief from Fe limitation and transition to N limitation in some taxa. Prochlorococcus (eHLI), Synechococcus (sub-cluster 5.3) and Alphaproteobacteria SAR11 clade (HIMB59) showed the strongest responses to the Fe enrichment. In addition, members of uncharacterized lineages also responded. The MicroTOOLs microarray provides a robust tool for comprehensive characterization of major functional groups of microbes in the open ocean, and the design can be easily amended for specific environments and research questions. PMID:24477198

  20. The evolutionary reality of higher taxa in mammals

    PubMed Central

    Humphreys, Aelys M.; Barraclough, Timothy G.

    2014-01-01

    Species are generally regarded as a fundamental unit of biodiversity. By contrast, higher taxa such as genera and families, while widely used as biodiversity metrics and for classification and communication, are generally not believed to be shaped by shared evolutionary processes in the same way as species. We use simulations to show that processes which are important for emergence of evolutionarily significant units (ESUs) at the species level, namely geographical isolation and ecological divergence, can generate evolutionary independence above the species level and thereby lead to emergence of discrete phylogenetic clusters (higher ESUs). Extending phylogenetic approaches for delimiting evolutionarily significant species to broader phylogenetic scales, we find evidence for the existence of higher ESUs in mammals. In carnivores, euungulates and lagomorphs the hierarchical level of units detected correspond, on average, to the level of family or genus in traditional taxonomy. The units in euungulates are associated with divergent patterns of body mass, consistent with occupation of distinct ecological zones. Our findings demonstrate a new framework for studying biodiversity that unifies approaches at species and higher levels, thus potentially restoring higher taxa to their historical status as natural entities. PMID:24695424

  1. The impact of rare taxa on a fish index of biotic integrity

    USGS Publications Warehouse

    Wan, H.; Chizinski, C.J.; Dolph, C.L.; Vondracek, B.; Wilson, B.N.

    2010-01-01

    The index of biotic integrity (IBI) is a commonly used bioassessment tool that integrates abundance and richness measures to assess water quality. In developing IBIs that are both responsive to human disturbance and resistant to natural variability and sampling error, water managers must decide how to weigh information about rare and abundant taxa, which in turn requires an understanding of the sensitivity of indices to rare taxa. Herein, we investigated the influence of rare fish taxa (within the lower 5% of rank abundance curves) on IBI metric and total scores for stream sites in two of Minnesota's major river basins, the St. Croix (n = 293 site visits) and Upper Mississippi (n = 210 site visits). We artificially removed rare taxa from biological samples by (1) separately excluding each individual taxon that fell within the lower 5% of rank abundance curves; (2) simultaneously excluding all taxa that had an abundance of one (singletons) or two (doubletons); and (3) simultaneously excluding all taxa that fell within the lower 5% of rank abundance curves. We then compared IBI metric and total scores before and after removal of rare taxa using the normalized root mean square error (nRMSE) and regression analysis. The difference in IBI metric and total scores increased as more taxa were removed. Moreover, when multiple rare taxa were removed, the nRMSE was related to sample abundance and to total taxa richness, with greater nRMSE observed in samples with a larger number of taxa or sample abundance. Metrics based on relative abundance of fish taxa were less sensitive to the loss of rare taxa, whereas those based on taxa richness were more sensitive, because taxa richness metrics give more weight to rare taxa compared to the relative abundance metrics. ?? 2010 Elsevier Ltd.

  2. Silurian horseshoe crab illuminates the evolution of arthropod limbs.

    PubMed

    Briggs, Derek E G; Siveter, Derek J; Siveter, David J; Sutton, Mark D; Garwood, Russell J; Legg, David

    2012-09-25

    The basic arrangement of limbs in euarthropods consists of a uniramous head appendage followed by a series of biramous appendages. The body is divided into functional units or tagmata which are usually distinguished by further differentiation of the limbs. The living horseshoe crabs are remnants of a much larger diversity of aquatic chelicerates. The limbs of the anterior and posterior divisions of the body of living horseshoe crabs differ in the loss of the outer and inner ramus, respectively, of an ancestral biramous limb. Here we report a new fossil horseshoe crab from the mid-Silurian Lagerstätte in Herefordshire, United Kingdom (approximately 425 Myr B.P.), a site that has yielded a remarkably preserved assemblage of soft-bodied fossils. The limbs of the new form can be homologized with those of living Limulus, but retain an ancestral biramous morphology. Remarkably, however, the two limb branches originate separately, providing fossil evidence to suggest that repression or loss of gene expression might have given rise to the appendage morphology of Limulus. Both branches of the prosomal limbs of this new fossil are robust and segmented in contrast to their morphology in Cambrian arthropods, revealing that a true biramous limb was once present in chelicerates as well as in the mandibulates. PMID:22967511

  3. Silurian horseshoe crab illuminates the evolution of arthropod limbs

    NASA Astrophysics Data System (ADS)

    Briggs, Derek E. G.; Siveter, Derek J.; Siveter, David J.; Sutton, Mark D.; Garwood, Russell J.; Legg, David

    2012-09-01

    The basic arrangement of limbs in euarthropods consists of a uniramous head appendage followed by a series of biramous appendages. The body is divided into functional units or tagmata which are usually distinguished by further differentiation of the limbs. The living horseshoe crabs are remnants of a much larger diversity of aquatic chelicerates. The limbs of the anterior and posterior divisions of the body of living horseshoe crabs differ in the loss of the outer and inner ramus, respectively, of an ancestral biramous limb. Here we report a new fossil horseshoe crab from the mid-Silurian Lagerstätte in Herefordshire, United Kingdom (approximately 425 Myr B.P.), a site that has yielded a remarkably preserved assemblage of soft-bodied fossils. The limbs of the new form can be homologized with those of living Limulus, but retain an ancestral biramous morphology. Remarkably, however, the two limb branches originate separately, providing fossil evidence to suggest that repression or loss of gene expression might have given rise to the appendage morphology of Limulus. Both branches of the prosomal limbs of this new fossil are robust and segmented in contrast to their morphology in Cambrian arthropods, revealing that a true biramous limb was once present in chelicerates as well as in the mandibulates.

  4. No Accumulation of Transposable Elements in Asexual Arthropods.

    PubMed

    Bast, Jens; Schaefer, Ina; Schwander, Tanja; Maraun, Mark; Scheu, Stefan; Kraaijeveld, Ken

    2016-03-01

    Transposable elements (TEs) and other repetitive DNA can accumulate in the absence of recombination, a process contributing to the degeneration of Y-chromosomes and other nonrecombining genome portions. A similar accumulation of repetitive DNA is expected for asexually reproducing species, given their entire genome is effectively nonrecombining. We tested this expectation by comparing the whole-genome TE loads of five asexual arthropod lineages and their sexual relatives, including asexual and sexual lineages of crustaceans (Daphnia water fleas), insects (Leptopilina wasps), and mites (Oribatida). Surprisingly, there was no evidence for increased TE load in genomes of asexual as compared to sexual lineages, neither for all classes of repetitive elements combined nor for specific TE families. Our study therefore suggests that nonrecombining genomes do not accumulate TEs like nonrecombining genomic regions of sexual lineages. Even if a slight but undetected increase of TEs were caused by asexual reproduction, it appears to be negligible compared to variance between species caused by processes unrelated to reproductive mode. It remains to be determined if molecular mechanisms underlying genome regulation in asexuals hamper TE activity. Alternatively, the differences in TE dynamics between nonrecombining genomes in asexual lineages versus nonrecombining genome portions in sexual species might stem from selection for benign TEs in asexual lineages because of the lack of genetic conflict between TEs and their hosts and/or because asexual lineages may only arise from sexual ancestors with particularly low TE loads. PMID:26560353

  5. Inference on arthropod demographic parameters: computational advances using R.

    PubMed

    Maia, Aline De Holanda Nunes; Pazianotto, Ricardo Antonio De Almeida; Luiz, Alfredo José Barreto; Marinho-Prado, Jeanne Scardini; Pervez, Ahmad

    2014-02-01

    We developed a computer program for life table analysis using the open source, free software programming environment R. It is useful to quantify chronic nonlethal effects of treatments on arthropod populations by summarizing information on their survival and fertility in key population parameters referred to as fertility life table parameters. Statistical inference on fertility life table parameters is not trivial because it requires the use of computationally intensive methods for variance estimation. Our codes present some advantages with respect to a previous program developed in Statistical Analysis System. Additional multiple comparison tests were incorporated for the analysis of qualitative factors; a module for regression analysis was implemented, thus, allowing analysis of quantitative factors such as temperature or agrochemical doses; availability is granted for users, once it was developed using an open source, free software programming environment. To illustrate the descriptive and inferential analysis implemented in lifetable.R, we present and discuss two examples: 1) a study quantifying the influence of the proteinase inhibitor berenil on the eucalyptus defoliator Thyrinteina arnobia (Stoll) and 2) a study investigating the influence of temperature on demographic parameters of a predaceous ladybird, Hippodamia variegata (Goeze). PMID:24665730

  6. No Accumulation of Transposable Elements in Asexual Arthropods

    PubMed Central

    Bast, Jens; Schaefer, Ina; Schwander, Tanja; Maraun, Mark; Scheu, Stefan; Kraaijeveld, Ken

    2016-01-01

    Transposable elements (TEs) and other repetitive DNA can accumulate in the absence of recombination, a process contributing to the degeneration of Y-chromosomes and other nonrecombining genome portions. A similar accumulation of repetitive DNA is expected for asexually reproducing species, given their entire genome is effectively nonrecombining. We tested this expectation by comparing the whole-genome TE loads of five asexual arthropod lineages and their sexual relatives, including asexual and sexual lineages of crustaceans (Daphnia water fleas), insects (Leptopilina wasps), and mites (Oribatida). Surprisingly, there was no evidence for increased TE load in genomes of asexual as compared to sexual lineages, neither for all classes of repetitive elements combined nor for specific TE families. Our study therefore suggests that nonrecombining genomes do not accumulate TEs like nonrecombining genomic regions of sexual lineages. Even if a slight but undetected increase of TEs were caused by asexual reproduction, it appears to be negligible compared to variance between species caused by processes unrelated to reproductive mode. It remains to be determined if molecular mechanisms underlying genome regulation in asexuals hamper TE activity. Alternatively, the differences in TE dynamics between nonrecombining genomes in asexual lineages versus nonrecombining genome portions in sexual species might stem from selection for benign TEs in asexual lineages because of the lack of genetic conflict between TEs and their hosts and/or because asexual lineages may only arise from sexual ancestors with particularly low TE loads. PMID:26560353

  7. Arthropod eye-inspired digital camera with unique imaging characteristics

    NASA Astrophysics Data System (ADS)

    Xiao, Jianliang; Song, Young Min; Xie, Yizhu; Malyarchuk, Viktor; Jung, Inhwa; Choi, Ki-Joong; Liu, Zhuangjian; Park, Hyunsung; Lu, Chaofeng; Kim, Rak-Hwan; Li, Rui; Crozier, Kenneth B.; Huang, Yonggang; Rogers, John A.

    2014-06-01

    In nature, arthropods have a remarkably sophisticated class of imaging systems, with a hemispherical geometry, a wideangle field of view, low aberrations, high acuity to motion and an infinite depth of field. There are great interests in building systems with similar geometries and properties due to numerous potential applications. However, the established semiconductor sensor technologies and optics are essentially planar, which experience great challenges in building such systems with hemispherical, compound apposition layouts. With the recent advancement of stretchable optoelectronics, we have successfully developed strategies to build a fully functional artificial apposition compound eye camera by combining optics, materials and mechanics principles. The strategies start with fabricating stretchable arrays of thin silicon photodetectors and elastomeric optical elements in planar geometries, which are then precisely aligned and integrated, and elastically transformed to hemispherical shapes. This imaging device demonstrates nearly full hemispherical shape (about 160 degrees), with densely packed artificial ommatidia. The number of ommatidia (180) is comparable to those of the eyes of fire ants and bark beetles. We have illustrated key features of operation of compound eyes through experimental imaging results and quantitative ray-tracing-based simulations. The general strategies shown in this development could be applicable to other compound eye devices, such as those inspired by moths and lacewings (refracting superposition eyes), lobster and shrimp (reflecting superposition eyes), and houseflies (neural superposition eyes).

  8. Systemic immediate allergic reactions to arthropod stings and bites.

    PubMed

    Bircher, Andreas J

    2005-01-01

    Most of the encounters with biting and stinging insects result in more or less pronounced localized reactions. Typically, urticarial wheals and papular reactions are observed. Less often local bullous or hemorrhagic or disseminated papular reactions, particularly in children and immunologically naive adults, may be seen. With the exception of bee and wasp venom allergies, immediate-type allergic reactions to arthropod stings and bites are rare. Systemic IgE-mediated hypersensitivity has also been reported from additional hymenoptera species, e.g. hornets, bumble bees and ants. Rare are systemic reactions to mosquitoes, flies or kissing bugs and exceptional from ticks, bed bugs, moths, caterpillars and spiders. A major problem is the often lacking standardization of extracts for skin testing and for the determination of specific IgE. Some of the allergens have been characterized and few of them synthesized using recombinant techniques. Most investigations have been made with whole-body extracts or extracts from salivary glands, while desensitization has rarely been attempted. Currently, primary prevention by avoidance of stings and bites, and adequate instruction of sensitized individuals in the use of emergency drugs are mandatory. PMID:15724094

  9. Death rates reflect accumulating brain damage in arthropods.

    PubMed

    Fonseca, Duane B; Brancato, Carolina L; Prior, Andrew E; Shelton, Peter M J; Sheehy, Matt R J

    2005-09-22

    We present the results of the first quantitative, whole-lifespan study of the relationship between age-specific neurolipofuscin concentration and natural mortality rate in any organism. In a convenient laboratory animal, the African migratory locust, Locusta migratoria, we find an unusual delayed-onset neurolipofuscin accumulation pattern that is highly correlated with exponentially accelerating age-specific Gompertz-Makeham death rates in both males (r=0.93, p=0.0064) and females (r=0.97, p=0.0052). We then test the conservation of this association by aggregating the locust results with available population-specific data for a range of other terrestrial, freshwater, marine, tropical and temperate arthropods whose longevities span three orders of magnitude. This synthesis shows that the strong association between neurolipofuscin deposition and natural mortality is a phylogenetically and environmentally widespread phenomenon (r=0.96, p < 0.0001). These results highlight neurolipofuscin as a unique and outstanding integral biomarker of ageing. They also offer compelling evidence for the proposal that, in vital organs like the brain, either the accumulation of toxic garbage in the form of lipofuscin itself, or the particular molecular reactions underlying lipofuscinogenesis, including free-radical damage, are the primary events in senescence. PMID:16191601

  10. [Structure of parasitic arthropod communities in forest small mammals].

    PubMed

    Balashov, Iu S

    2004-01-01

    Species composition and structure of ectoparasite arthropod communities were examined all year round six years in the bank vole Clethrionomys glareolus, Ural wood mouse Apodemus uralensis and the common shrew Sorex araneus in forests of the Ilmen'-Volkhov depression. In total, 4500 host samples have been examined and all ectoparasites have been collected. The species composition of ectoparasite community in small mammal species are as follows: the bank vole--29 insect, tick and mite species, the common shrew--23 species, the Ural wood mouse--16 species. In forest biotopes, many temporary ectoparasitic species occur on several host species living in the same habitats under a forest canopy and contacting each other. A parasitic supracommunity in the ecosystem examined has a pool of temporary ectoparasites, which is available for all the community of small mammals. A role of different rodent and shrew species are hosts of insects and ticks changes depending on a density of potential host populations and numerous other environment factors. PMID:15656091

  11. Arthropod phylogeny based on eight molecular loci and morphology

    NASA Technical Reports Server (NTRS)

    Giribet, G.; Edgecombe, G. D.; Wheeler, W. C.

    2001-01-01

    The interrelationships of major clades within the Arthropoda remain one of the most contentious issues in systematics, which has traditionally been the domain of morphologists. A growing body of DNA sequences and other types of molecular data has revitalized study of arthropod phylogeny and has inspired new considerations of character evolution. Novel hypotheses such as a crustacean-hexapod affinity were based on analyses of single or few genes and limited taxon sampling, but have received recent support from mitochondrial gene order, and eye and brain ultrastructure and neurogenesis. Here we assess relationships within Arthropoda based on a synthesis of all well sampled molecular loci together with a comprehensive data set of morphological, developmental, ultrastructural and gene-order characters. The molecular data include sequences of three nuclear ribosomal genes, three nuclear protein-coding genes, and two mitochondrial genes (one protein coding, one ribosomal). We devised new optimization procedures and constructed a parallel computer cluster with 256 central processing units to analyse molecular data on a scale not previously possible. The optimal 'total evidence' cladogram supports the crustacean-hexapod clade, recognizes pycnogonids as sister to other euarthropods, and indicates monophyly of Myriapoda and Mandibulata.

  12. A Comparison of the Pitfall Trap, Winkler Extractor and Berlese Funnel for Sampling Ground-Dwelling Arthropods in Tropical Montane Cloud Forests

    PubMed Central

    Sabu, Thomas K.; Shiju, Raj T.; Vinod, KV.; Nithya, S.

    2011-01-01

    Little is known about the ground-dwelling arthropod diversity in tropical montane cloud forests (TMCF). Due to unique habitat conditions in TMCFs with continuously wet substrates and a waterlogged forest floor along with the innate biases of the pitfall trap, Berlese funnel and Winkler extractor are certain to make it difficult to choose the most appropriate method to sample the ground-dwelling arthropods in TMCFs. Among the three methods, the Winkler extractor was the most efficient method for quantitative data and pitfall trapping for qualitative data for most groups. Inclusion of floatation method as a complementary method along with the Winkler extractor would enable a comprehensive quantitative survey of ground-dwelling arthropods. Pitfall trapping is essential for both quantitative and qualitative sampling of Diplopoda, Opiliones, Orthoptera, and Diptera. The Winkler extractor was the best quantitative method for Psocoptera, Araneae, Isopoda, and Formicidae; and the Berlese funnel was best for Collembola and Chilopoda. For larval forms of different insect orders and the Acari, all the three methods were equally effective. PMID:21529148

  13. Do the rich get richer? Varying effects of tree species identity and diversity on the richness of understory taxa

    USGS Publications Warehouse

    Champagne, Juilette; Paine, C. E. Timothy; Schoolmaster, Donald; Stejskal, Robert; Volařík, Daniel; Šebesta, Jan; Trnka, Filip; Koutecký, Tomáš; Švarc, Petr; Svátek, Martin; Hector, Andy; Matula, Radim

    2016-01-01

    Understory herbs and soil invertebrates play key roles in soil formation and nutrient cycling in forests. Studies suggest that diversity in the canopy and in the understory are positively associated, but these studies often confound the effects of tree species diversity with those of tree species identity and abiotic conditions. We combined extensive field sampling with structural equation modeling to evaluate the simultaneous effects of tree diversity on the species diversity of understory herbs, beetles, and earthworms. The diversity of earthworms and saproxylic beetles was directly and positively associated with tree diversity, presumably because species of both these taxa specialize on certain species of trees. Tree identity also strongly affected diversity in the understory, especially for herbs, likely as a result of interspecific differences in canopy light transmittance or litter decomposition rates. Our results suggest that changes in forest management will disproportionately affect certain understory taxa. For instance, changes in canopy diversity will affect the diversity of earthworms and saproxylic beetles more than changes in tree species composition, whereas the converse would be expected for understory herbs and detritivorous beetles. We conclude that the effects of tree diversity on understory taxa can vary from positive to negative and may affect biogeochemical cycling in temperate forests. Thus, maintaining high diversity in temperate forests can promote the diversity of multiple taxa in the understory.

  14. The roles of Lazarus taxa and refugia through the Ordovician-Silurian transition: data from the Brachiopoda

    NASA Astrophysics Data System (ADS)

    Rong, J.-Y.; Boucot, A. J.; Harper, D. A.; Zhan, R.-B.; Neuman, R. B.

    2003-04-01

    Global analyses of nearly 90 families and 275 genera of brachiopods from the middle Ashgill through the Hirnantian (Ordovician) to the lower-middle Rhuddanian (Silurian) suggest that about 60% and 40% of the total number of genera were eliminated at the first and second phases of the end Ordovician extinction event, respectively. Among the 85 surviving genera, about 50 with declining and 10 with proliferating abundances are known from the Hirnantian together with about 20 provisional Lazarus taxa. The Lazarus taxa are essentially survivors and form the extremity of the declining genera. The distributions of declining genera and relicts during the crisis interval shows a random and sporadic pattern, suggesting there was no single, common refugium for end Ordovician brachiopods. In addition to their biological attributes, a markedly decreased population size together with taphonomic failure and poor preservation, and collecting bias have contributed towards the distributional trends apparent during the event. The development of declining genera during the extinction may be linked to their palaeogeographical setting, the phylogenetic history of the taxa, and the ambient environmental conditions. This new global database has significantly reduced the number of Lazarus taxa and minimizes the number of possible locations for collective refugia during the end Ordovician crisis. Nevertheless, the atrypids, athyridids, pentamerids, and spiriferids had more limited distributions during the crisis interval but formed the locus for a Silurian diversification of the phylum into carbonate environments possibly around the Rhuddanian-Aeronian boundary.

  15. Mineral cycling in soil and litter arthropod food chains. Progress report, November 1, 1980-October 31, 1981

    SciTech Connect

    Crossley, D.A. Jr.

    1980-06-15

    Progress and current status are reported for research projects concerned with mineral element and nutrient dynamics in soil arthropod food chains. Research is performed within the larger context of terrestrial decomposition, in which soil arthropods may act as regulators of nutrient dynamics during decomposition. Research is measuring rates of nutrient accumulation and excretion by using radioactive tracer analogs of nutrients. This year, emphasis has been placed on field work in which soil arthropod population size and nutrients inputs were varied experimentally. The presence of microarthropods in field microcosms increased the mineralization of N and P in each case, but rates were not correlated with arthropod densities. Experiments recently started are using both arthropod and microfloral inhibitors, in open systems on the forest floor, with the objective of quantifying arthropod enhancement of microbial immobilization of nutrients.

  16. The effects of global change on the threat of exotic arthropods and arthropod-borne pathogens to livestock in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arthropod-borne diseases are an important part of the group of foreign animal diseases that command attention from federal, state, and local animal health authorities in the United States because of the potential for adverse local and regional animal health impacts, but also because of possible loss...

  17. Extinction, diversity and survivorship of taxa in the fossil record

    PubMed Central

    Newman, M. E. J.; Sibani, P.

    1999-01-01

    Using data drawn from large-scale databases, a number of interesting trends in the fossil record have been observed in recent years. These include the average decline in extinction rates throughout the Phanerozoic, the average increase in standing diversity, correlations between rates of origination and extinction, and simple laws governing the form of survivorship curves and the distribution of the lifetimes of taxa. In this paper we derive a number of mathematical relationships between these quantities and show how these different trends are interrelated. We also derive a variety of constraints on the possible forms of these trends, such as limits on the rate at which extinction may decline and limits on the allowed difference between extinction and origination rates at any given time.

  18. Transposable elements in sexual and ancient asexual taxa

    PubMed Central

    Arkhipova, Irina; Meselson, Matthew

    2000-01-01

    Sexual reproduction allows deleterious transposable elements to proliferate in populations, whereas the loss of sex, by preventing their spread, has been predicted eventually to result in a population free of such elements [Hickey, D. A. (1982) Genetics 101, 519–531]. We tested this expectation by screening representatives of a majority of animal phyla for LINE-like and gypsy-like reverse transcriptases and mariner/Tc1-like transposases. All species tested positive for reverse transcriptases except rotifers of the class Bdelloidea, the largest eukaryotic taxon in which males, hermaphrodites, and meiosis are unknown and for which ancient asexuality is supported by molecular genetic evidence. Mariner-like transposases are distributed sporadically among species and are present in bdelloid rotifers. The remarkable lack of LINE-like and gypsy-like retrotransposons in bdelloids and their ubiquitous presence in other taxa support the view that eukaryotic retrotransposons are sexually transmitted nuclear parasites and that bdelloid rotifers evolved asexually. PMID:11121049

  19. More taxa, more characters: the hoatzin problem is still unresolved.

    PubMed

    Sorenson, Michael D; Oneal, Elen; Garcia-Moreno, Jaime; Mindell, David P

    2003-09-01

    The apparently rapid and ancient diversification of many avian orders complicates the resolution of their relationships using molecular data. Recent studies based on complete mitochondrial DNA (mtDNA) sequences or shorter lengths of nuclear sequence have helped corroborate the basic structure of the avian tree (e.g., a basal split between Paleognathae and Neognathae) but have made relatively little progress in resolving relationships among the many orders within Neoaves. We explored the potential of a moderately sized mtDNA data set ( approximately 5000 bp for each of 41 taxa), supplemented with data from a nuclear intron ( approximately 700 bp per taxon), to resolve relationships among avian orders. Our sampling of taxa addresses two issues: (1). the sister relationship and monophyly, respectively, of Anseriformes and Galliformes and (2). relationships of the enigmatic hoatzin Opisthocomus hoazin. Our analyses support a basal split between Galloanserae and Neoaves within Neognathae and monophyly of both Galliformes and Anseriformes. Within Galliformes, megapodes and then cracids branch basally. Within Anseriformes, mitochondrial data support a screamer (Anhimidae) plus magpie goose (Anseranatidae) clade. This result, however, may be an artifact of divergent base composition in one of the two anatids we sampled. With deletion of the latter taxon, Anseranas is sister to anatids as in traditional arrangements and recent morphological studies. Although our data provide limited resolution of relationships within Neoaves, we find no support for a sister relationship between either cuckoos (Cuculiformes) or turacos (Musophagiformes) and hoatzin. Both mitochondrial and nuclear data are consistent with a relationship between hoatzin and doves (Columbiformes), although this result is weakly supported. We also show that mtDNA sequences reported in another recent study included pervasive errors that biased the analysis towards finding a sister relationship between hoatzin and

  20. Identifying sighting clusters of endangered taxa with historical records.

    PubMed

    Duffy, Karl J

    2011-04-01

    The probability and time of extinction of taxa is often inferred from statistical analyses of historical records. Many of these analyses require the exclusion of multiple records within a unit of time (i.e., a month or a year). Nevertheless, spatially explicit, temporally aggregated data may be useful for identifying clusters of sightings (i.e., sighting clusters) in space and time. Identification of sighting clusters highlights changes in the historical recording of endangered taxa. I used two methods to identify sighting clusters in historical records: the Ederer-Myers-Mantel (EMM) test and the space-time permutation scan (STPS). I applied these methods to the spatially explicit sighting records of three species of orchids that are listed as endangered in the Republic of Ireland under the Wildlife Act (1976): Cephalanthera longifolia, Hammarbya paludosa, and Pseudorchis albida. Results with the EMM test were strongly affected by the choice of the time interval, and thus the number of temporal samples, used to examine the records. For example, sightings of P. albida clustered when the records were partitioned into 20-year temporal samples, but not when they were partitioned into 22-year temporal samples. Because the statistical power of EMM was low, it will not be useful when data are sparse. Nevertheless, the STPS identified regions that contained sighting clusters because it uses a flexible scanning window (defined by cylinders of varying size that move over the study area and evaluate the likelihood of clustering) to detect them, and it identified regions with high and regions with low rates of orchid sightings. The STPS analyses can be used to detect sighting clusters of endangered species that may be related to regions of extirpation and may assist in the categorization of threat status. PMID:21129031

  1. Fossil preservation and the stratigraphic ranges of taxa

    NASA Technical Reports Server (NTRS)

    Foote, M.; Raup, D. M.

    1996-01-01

    The incompleteness of the fossil record hinders the inference of evolutionary rates and patterns. Here, we derive relationships among true taxonomic durations, preservation probability, and observed taxonomic ranges. We use these relationships to estimate original distributions of taxonomic durations, preservation probability, and completeness (proportion of taxa preserved), given only the observed ranges. No data on occurrences within the ranges of taxa are required. When preservation is random and the original distribution of durations is exponential, the inference of durations, preservability, and completeness is exact. However, reasonable approximations are possible given non-exponential duration distributions and temporal and taxonomic variation in preservability. Thus, the approaches we describe have great potential in studies of taphonomy, evolutionary rates and patterns, and genealogy. Analyses of Upper Cambrian-Lower Ordovician trilobite species, Paleozoic crinoid genera, Jurassic bivalve species, and Cenozoic mammal species yield the following results: (1) The preservation probability inferred from stratigraphic ranges alone agrees with that inferred from the analysis of stratigraphic gaps when data on the latter are available. (2) Whereas median durations based on simple tabulations of observed ranges are biased by stratigraphic resolution, our estimates of median duration, extinction rate, and completeness are not biased.(3) The shorter geologic ranges of mammalian species relative to those of bivalves cannot be attributed to a difference in preservation potential. However, we cannot rule out the contribution of taxonomic practice to this difference. (4) In the groups studied, completeness (proportion of species [trilobites, bivalves, mammals] or genera [crinoids] preserved) ranges from 60% to 90%. The higher estimates of completeness at smaller geographic scales support previous suggestions that the incompleteness of the fossil record reflects loss of

  2. Mineral cycling in soil and litter arthropod food chains. Three-year progress report, February 1, 1984-January 31, 1987

    SciTech Connect

    Crossley, D.A. Jr.

    1986-08-29

    This report summarizes progress in a three-year research project on the influence of soil arthropods (mites, collembolans, insects, millipedes and others) upon decomposition rates and nutrient dynamics in decaying vegetable matter. Research has concentrated on two aspects of elemental dynamics in decomposing organic matter: Effects of arthropods on rates of decomposition and nutrient loss (mineralization of carbon and other elements), and arthropod stimulation of microbial immobilization of nutrient elements during decomposition.

  3. Large-scale experimental landscapes reveal distinctive effects of patch shape and connectivity on arthropod communities.

    SciTech Connect

    Orrock, John, L.; Curler, Gregory, R.; Danielson, Brent, J.; Coyle, David. R.

    2011-09-14

    The size, shape, and isolation of habitat patches can affect organism behavior and population dynamics, but little is known about the relative role of shape and connectivity in affecting ecological communities at large spatial scales. Using six sampling sessions from July 2001 until August 2002, we collected 33,685 arthropods throughout seven 12-ha experimental landscapes consisting of clear-cut patches surrounded by a matrix of mature pine forest. Patches were explicitly designed to manipulate connectivity (via habitat corridors) independently of area and edge effects. We found that patch shape, rather than connectivity, affected ground-dwelling arthropod richness and beta diversity (i.e. turnover of genera among patches). Arthropod communities contained fewer genera and exhibited less turnover in high-edge connected and high-edge unconnected patches relative to low-edge unconnected patches of similar area. Connectivity, rather than patch shape, affected the evenness of ground-dwelling arthropod communities; regardless of patch shape, high-edge connected patches had lower evenness than low- or high-edge unconnected patches. Among the most abundant arthropod orders, increased richness in low-edge unconnected patches was largely due to increased richness of Coleoptera, whereas Hymenoptera played an important role in the lower evenness in connected patches and patterns of turnover. These findings suggest that anthropogenic habitat alteration can have distinct effects on ground-dwelling arthropod communities that arise due to changes in shape and connectivity. Moreover, this work suggests that corridors, which are common conservation tools that change both patch shape and connectivity, can have multiple effects on arthropod communities via different mechanisms, and each effect may alter components of community structure.

  4. Possible effects of global environmental changes on Antarctic benthos: a synthesis across five major taxa.

    PubMed

    Ingels, Jeroen; Vanreusel, Ann; Brandt, Angelika; Catarino, Ana I; David, Bruno; De Ridder, Chantal; Dubois, Philippe; Gooday, Andrew J; Martin, Patrick; Pasotti, Francesca; Robert, Henri

    2012-02-01

    Because of the unique conditions that exist around the Antarctic continent, Southern Ocean (SO) ecosystems are very susceptible to the growing impact of global climate change and other anthropogenic influences. Consequently, there is an urgent need to understand how SO marine life will cope with expected future changes in the environment. Studies of Antarctic organisms have shown that individual species and higher taxa display different degrees of sensitivity to environmental shifts, making it difficult to predict overall community or ecosystem responses. This emphasizes the need for an improved understanding of the Antarctic benthic ecosystem response to global climate change using a multitaxon approach with consideration of different levels of biological organization. Here, we provide a synthesis of the ability of five important Antarctic benthic taxa (Foraminifera, Nematoda, Amphipoda, Isopoda, and Echinoidea) to cope with changes in the environment (temperature, pH, ice cover, ice scouring, food quantity, and quality) that are linked to climatic changes. Responses from individual to the taxon-specific community level to these drivers will vary with taxon but will include local species extinctions, invasions of warmer-water species, shifts in diversity, dominance, and trophic group composition, all with likely consequences for ecosystem functioning. Limitations in our current knowledge and understanding of climate change effects on the different levels are discussed. PMID:22423336

  5. Possible effects of global environmental changes on Antarctic benthos: a synthesis across five major taxa

    PubMed Central

    Ingels, Jeroen; Vanreusel, Ann; Brandt, Angelika; Catarino, Ana I; David, Bruno; De Ridder, Chantal; Dubois, Philippe; Gooday, Andrew J; Martin, Patrick; Pasotti, Francesca; Robert, Henri

    2012-01-01

    Because of the unique conditions that exist around the Antarctic continent, Southern Ocean (SO) ecosystems are very susceptible to the growing impact of global climate change and other anthropogenic influences. Consequently, there is an urgent need to understand how SO marine life will cope with expected future changes in the environment. Studies of Antarctic organisms have shown that individual species and higher taxa display different degrees of sensitivity to environmental shifts, making it difficult to predict overall community or ecosystem responses. This emphasizes the need for an improved understanding of the Antarctic benthic ecosystem response to global climate change using a multitaxon approach with consideration of different levels of biological organization. Here, we provide a synthesis of the ability of five important Antarctic benthic taxa (Foraminifera, Nematoda, Amphipoda, Isopoda, and Echinoidea) to cope with changes in the environment (temperature, pH, ice cover, ice scouring, food quantity, and quality) that are linked to climatic changes. Responses from individual to the taxon-specific community level to these drivers will vary with taxon but will include local species extinctions, invasions of warmer-water species, shifts in diversity, dominance, and trophic group composition, all with likely consequences for ecosystem functioning. Limitations in our current knowledge and understanding of climate change effects on the different levels are discussed. PMID:22423336

  6. Pollinator sharing and gene flow among closely related sympatric dioecious fig taxa.

    PubMed

    Wang, Gang; Cannon, Charles H; Chen, Jin

    2016-04-13

    Hybridization and insect pollination are widely believed to increase rates of plant diversification. The extreme diversity of figs (Ficus) and their obligate pollinators, fig wasps (Agaonidae), provides an opportunity to examine the possible role of pollinator-mediated hybridization in plant diversification. Increasing evidence suggests that pollinator sharing and hybridization occurs among fig taxa, despite relatively strict coevolution with the pollinating wasp. Using five sympatric dioecious fig taxa and their pollinators, we examine the degree of pollinator sharing and inter-taxa gene flow. We experimentally test pollinator preference for floral volatiles, the main host recognition signal, from different figs. All five fig taxa shared pollinators with other taxa, and gene flow occurred between fig taxa within and between sections. Floral volatiles of each taxon attracted more than one pollinator species. Floral volatiles were more similar between closely related figs, which experienced higher levels of pollinator sharing and inter-taxa gene flow. This study demonstrates that pollinator sharing and inter-taxa gene flow occurs among closely related sympatric dioecious fig taxa and that pollinators choose the floral volatiles of multiple fig taxa. The implications of pollinator sharing and inter-taxa gene flow on diversification, occurring even in this highly specialized obligate pollination system, require further study. PMID:27075252

  7. Indirect suppression of photosynthesis on individual leaves by arthropod herbivory

    PubMed Central

    Nabity, Paul D.; Zavala, Jorge A.; DeLucia, Evan H.

    2009-01-01

    Background Herbivory reduces leaf area, disrupts the function of leaves, and ultimately alters yield and productivity. Herbivore damage to foliage typically is assessed in the field by measuring the amount of leaf tissue removed and disrupted. This approach assumes the remaining tissues are unaltered, and plant photosynthesis and water balance function normally. However, recent application of thermal and fluorescent imaging technologies revealed that alterations to photosynthesis and transpiration propagate into remaining undamaged leaf tissue. Scope and Conclusions This review briefly examines the indirect effects of herbivory on photosynthesis, measured by gas exchange or chlorophyll fluorescence, and identifies four mechanisms contributing to the indirect suppression of photosynthesis in remaining leaf tissues: severed vasculature, altered sink demand, defence-induced autotoxicity, and defence-induced down-regulation of photosynthesis. We review the chlorophyll fluorescence and thermal imaging techniques used to gather layers of spatial data and discuss methods for compiling these layers to achieve greater insight into mechanisms contributing to the indirect suppression of photosynthesis. We also elaborate on a few herbivore-induced gene-regulating mechanisms which modulate photosynthesis and discuss the difficult nature of measuring spatial heterogeneity when combining fluorescence imaging and gas exchange technology. Although few studies have characterized herbivore-induced indirect effects on photosynthesis at the leaf level, an emerging literature suggests that the loss of photosynthetic capacity following herbivory may be greater than direct loss of photosynthetic tissues. Depending on the damage guild, ignoring the indirect suppression of photosynthesis by arthropods and other organisms may lead to an underestimate of their physiological and ecological impacts. PMID:18660492

  8. Desiccation as a mitigation tool to manage biofouling risks: trials on temperate taxa to elucidate factors influencing mortality rates.

    PubMed

    Hopkins, Grant A; Prince, Madeleine; Cahill, Patrick L; Fletcher, Lauren M; Atalah, Javier

    2016-01-01

    The desiccation tolerance of biofouling taxa (adults and early life-stages) was determined under both controlled and 'realistic' field conditions. Adults of the ascidian Ciona spp. died within 24 h. Mortality in the adult blue mussel Mytilus galloprovincialis occurred within 11 d under controlled conditions, compared with 7 d when held outside. The Pacific oyster Crassostrea gigas was the most desiccation-tolerant taxon tested (up to 34 d under controlled conditions). Biofouling orientated to direct sunlight showed faster mortality rates for all the taxa tested. Mortality in Mytilus juveniles took up to 24 h, compared with 8 h for Ciona, with greater survival at the higher temperature (18.5°C) and humidity (~95% RH) treatment combination. This study demonstrated that desiccation can be an effective mitigation method for a broad range of fouling taxa, especially their early life-stages. Further work is necessary to assess risks from other high-risk species such as algae and cyst forming species. PMID:26691450

  9. Disturbance and recovery of salt marsh arthropod communities following BP Deepwater Horizon oil spill.

    PubMed

    McCall, Brittany D; Pennings, Steven C

    2012-01-01

    Oil spills represent a major environmental threat to coastal wetlands, which provide a variety of critical ecosystem services to humanity. The U.S. Gulf of Mexico is a hub of oil and gas exploration activities that historically have impacted intertidal habitats such as salt marsh. Following the BP Deepwater Horizon oil spill, we sampled the terrestrial arthropod community and marine invertebrates found in stands of Spartina alterniflora, the most abundant plant in coastal salt marshes. Sampling occurred in 2010 as oil was washing ashore and a year later in 2011. In 2010, intertidal crabs and terrestrial arthropods (insects and spiders) were suppressed by oil exposure even in seemingly unaffected stands of plants; however, Littoraria snails were unaffected. One year later, crab and arthropods had largely recovered. Our work is the first attempt that we know of assessing vulnerability of the salt marsh arthropod community to oil exposure, and it suggests that arthropods are both quite vulnerable to oil exposure and quite resilient, able to recover from exposure within a year if host plants remain healthy. PMID:22412916

  10. Oak tree canker disease supports arthropod diversity in a natural ecosystem.

    PubMed

    Lee, Yong-Bok; An, Su Jung; Park, Chung Gyoo; Kim, Jinwoo; Han, Sangjo; Kwak, Youn-Sig

    2014-03-01

    Microorganisms have many roles in nature. They may act as decomposers that obtain nutrients from dead materials, while some are pathogens that cause diseases in animals, insects, and plants. Some are symbionts that enhance plant growth, such as arbuscular mycorrhizae and nitrogen fixation bacteria. However, roles of plant pathogens and diseases in natural ecosystems are still poorly understood. Thus, the current study addressed this deficiency by investigating possible roles of plant diseases in natural ecosystems, particularly, their positive effects on arthropod diversity. In this study, the model system was the oak tree (Quercus spp.) and the canker disease caused by Annulohypoxylon truncatum, and its effects on arthropod diversity. The oak tree site contained 44 oak trees; 31 had canker disease symptoms while 13 were disease-free. A total of 370 individual arthropods were detected at the site during the survey period. The arthropods belonged to 25 species, 17 families, and seven orders. Interestingly, the cankered trees had significantly higher biodiversity and richness compared with the canker-free trees. This study clearly demonstrated that arthropod diversity was supported by the oak tree canker disease. PMID:25288984

  11. Oak Tree Canker Disease Supports Arthropod Diversity in a Natural Ecosystem

    PubMed Central

    Lee, Yong-Bok; An, Su Jung; Park, Chung Gyoo; Kim, Jinwoo; Han, Sangjo; Kwak, Youn-Sig

    2014-01-01

    Microorganisms have many roles in nature. They may act as decomposers that obtain nutrients from dead materials, while some are pathogens that cause diseases in animals, insects, and plants. Some are symbionts that enhance plant growth, such as arbuscular mycorrhizae and nitrogen fixation bacteria. However, roles of plant pathogens and diseases in natural ecosystems are still poorly understood. Thus, the current study addressed this deficiency by investigating possible roles of plant diseases in natural ecosystems, particularly, their positive effects on arthropod diversity. In this study, the model system was the oak tree (Quercus spp.) and the canker disease caused by Annulohypoxylon truncatum, and its effects on arthropod diversity. The oak tree site contained 44 oak trees; 31 had canker disease symptoms while 13 were disease-free. A total of 370 individual arthropods were detected at the site during the survey period. The arthropods belonged to 25 species, 17 families, and seven orders. Interestingly, the cankered trees had significantly higher biodiversity and richness compared with the canker-free trees. This study clearly demonstrated that arthropod diversity was supported by the oak tree canker disease. PMID:25288984

  12. Surviving in a frozen desert: environmental stress physiology of terrestrial Antarctic arthropods.

    PubMed

    Teets, Nicholas M; Denlinger, David L

    2014-01-01

    Abiotic stress is one of the primary constraints limiting the range and success of arthropods, and nowhere is this more apparent than Antarctica. Antarctic arthropods have evolved a suite of adaptations to cope with extremes in temperature and water availability. Here, we review the current state of knowledge regarding the environmental physiology of terrestrial arthropods in Antarctica. To survive low temperatures, mites and Collembola are freeze-intolerant and rely on deep supercooling, in some cases supercooling below -30°C. Also, some of these microarthropods are capable of cryoprotective dehydration to extend their supercooling capacity and reduce the risk of freezing. In contrast, the two best-studied Antarctic insects, the midges Belgica antarctica and Eretmoptera murphyi, are freeze-tolerant year-round and rely on both seasonal and rapid cold-hardening to cope with decreases in temperature. A common theme among Antarctic arthropods is extreme tolerance of dehydration; some accomplish this by cuticular mechanisms to minimize water loss across their cuticle, while a majority have highly permeable cuticles but tolerate upwards of 50-70% loss of body water. Molecular studies of Antarctic arthropod stress physiology are still in their infancy, but several recent studies are beginning to shed light on the underlying mechanisms that govern extreme stress tolerance. Some common themes that are emerging include the importance of cuticular and cytoskeletal rearrangements, heat shock proteins, metabolic restructuring and cell recycling pathways as key mediators of cold and water stress in the Antarctic. PMID:24353207

  13. Incidence of a new sex-ratio-distorting endosymbiotic bacterium among arthropods.

    PubMed Central

    Weeks, Andrew R; Velten, Robert; Stouthamer, Richard

    2003-01-01

    Many intracellular micro-organisms are now known to cause reproductive abnormalities and other phenomena in their hosts. The endosymbiont Wolbachia is the best known of these reproductive manipulators owing to its extremely high incidence among arthropods and the diverse host effects it has been implicated as causing. However, recent evidence suggests that another intracellular bacterium, a Cytophaga-like organism (CLO), may also induce several reproductive effects in its hosts. Here, we present the first survey of arthropod hosts for infection by the CLO. We use a sensitive hemi-nested polymerase chain reaction method to screen 223 species from 20 arthropod orders for infection by the CLO and Wolbachia. The results indicate that, although not as prevalent as Wolbachia, the CLO infects a significant number of arthropod hosts (ca. 7.2%). In addition, double infections of the CLO and Wolbachia were found in individuals of seven arthropod species. Sequencing analysis of the 16S rDNA region of the CLO indicates evidence for horizontal transmission of the CLO strains. We discuss these results with reference to future studies on host effects induced by intracellular micro-organisms. PMID:12964989

  14. Modification and Application of a Leaf Blower-vac for Field Sampling of Arthropods.

    PubMed

    Zou, Yi; van Telgen, Mario D; Chen, Junhui; Xiao, Haijun; de Kraker, Joop; Bianchi, Felix J J A; van der Werf, Wopke

    2016-01-01

    Rice fields host a large diversity of arthropods, but investigating their population dynamics and interactions is challenging. Here we describe the modification and application of a leaf blower-vac for suction sampling of arthropod populations in rice. When used in combination with an enclosure, application of this sampling device provides absolute estimates of the populations of arthropods as numbers per standardized sampling area. The sampling efficiency depends critically on the sampling duration. In a mature rice crop, a two-minute sampling in an enclosure of 0.13 m(2) yields more than 90% of the arthropod population. The device also allows sampling of arthropods dwelling on the water surface or the soil in rice paddies, but it is not suitable for sampling fast flying insects, such as predatory Odonata or larger hymenopterous parasitoids. The modified blower-vac is simple to construct, and cheaper and easier to handle than traditional suction sampling devices, such as D-vac. The low cost makes the modified blower-vac also accessible to researchers in developing countries. PMID:27584040

  15. Tuning the white light spectrum of light emitting diode lamps to reduce attraction of nocturnal arthropods.

    PubMed

    Longcore, Travis; Aldern, Hannah L; Eggers, John F; Flores, Steve; Franco, Lesly; Hirshfield-Yamanishi, Eric; Petrinec, Laina N; Yan, Wilson A; Barroso, André M

    2015-05-01

    Artificial lighting allows humans to be active at night, but has many unintended consequences, including interference with ecological processes, disruption of circadian rhythms and increased exposure to insect vectors of diseases. Although ultraviolet and blue light are usually most attractive to arthropods, degree of attraction varies among orders. With a focus on future indoor lighting applications, we manipulated the spectrum of white lamps to investigate the influence of spectral composition on number of arthropods attracted. We compared numbers of arthropods captured at three customizable light-emitting diode (LED) lamps (3510, 2704 and 2728 K), two commercial LED lamps (2700 K), two commercial compact fluorescent lamps (CFLs; 2700 K) and a control. We configured the three custom LEDs to minimize invertebrate attraction based on published attraction curves for honeybees and moths. Lamps were placed with pan traps at an urban and two rural study sites in Los Angeles, California. For all invertebrate orders combined, our custom LED configurations were less attractive than the commercial LED lamps or CFLs of similar colour temperatures. Thus, adjusting spectral composition of white light to minimize attracting nocturnal arthropods is feasible; not all lights with the same colour temperature are equally attractive to arthropods. PMID:25780237

  16. Tuning the white light spectrum of light emitting diode lamps to reduce attraction of nocturnal arthropods

    PubMed Central

    Longcore, Travis; Aldern, Hannah L.; Eggers, John F.; Flores, Steve; Franco, Lesly; Hirshfield-Yamanishi, Eric; Petrinec, Laina N.; Yan, Wilson A.; Barroso, André M.

    2015-01-01

    Artificial lighting allows humans to be active at night, but has many unintended consequences, including interference with ecological processes, disruption of circadian rhythms and increased exposure to insect vectors of diseases. Although ultraviolet and blue light are usually most attractive to arthropods, degree of attraction varies among orders. With a focus on future indoor lighting applications, we manipulated the spectrum of white lamps to investigate the influence of spectral composition on number of arthropods attracted. We compared numbers of arthropods captured at three customizable light-emitting diode (LED) lamps (3510, 2704 and 2728 K), two commercial LED lamps (2700 K), two commercial compact fluorescent lamps (CFLs; 2700 K) and a control. We configured the three custom LEDs to minimize invertebrate attraction based on published attraction curves for honeybees and moths. Lamps were placed with pan traps at an urban and two rural study sites in Los Angeles, California. For all invertebrate orders combined, our custom LED configurations were less attractive than the commercial LED lamps or CFLs of similar colour temperatures. Thus, adjusting spectral composition of white light to minimize attracting nocturnal arthropods is feasible; not all lights with the same colour temperature are equally attractive to arthropods. PMID:25780237

  17. The origins of the arthropod nervous system: insights from the Onychophora.

    PubMed

    Whitington, Paul M; Mayer, Georg

    2011-05-01

    A revision of evolutionary relationships of the Arthropoda has provided fresh impetus to tracing the origins of the nervous system of this group of animals: other members of the Ecdysozoa possess a markedly different type of nervous system from both the arthropods and the annelid worms, with which they were previously grouped. Given their status as favoured sister taxon of the arthropods, Onychophora (velvet worms) are a key group for understanding the evolutionary changes that have taken place in the panarthropod (Arthropoda + Onychophora + Tardigrada) lineage. This article reviews our current knowledge of the structure and development of the onychophoran nervous system. The picture that emerges from these studies is that the nervous system of the panarthropod ancestor was substantially different from that of modern arthropods: this animal probably possessed a bipartite, rather than a tripartite brain; its nerve cord displayed only a limited degree of segmentation; and neurons were more numerous but more uniform in morphology than in living arthropods. These observations suggest an evolutionary scenario, by which the arthropod nervous system evolved from a system of orthogonally crossing nerve tracts present in both a presumed protostome ancestor and many extant worm-like invertebrates, including the onychophorans. PMID:21315833

  18. Non-repeatable science: assessing the frequency of voucher specimen deposition reveals that most arthropod research cannot be verified

    PubMed Central

    2015-01-01

    Scientific findings need to be verifiable and grounded in repeatability. With specimen-level research this is in part achieved with the deposition of voucher specimens. These are labeled, curated, data-based specimens that have been deposited in a collection or museum, available for verification of the work and to ensure researchers are calling the same taxa by the same names. Voucher specimens themselves are the subject of research, from the discovery of new species by taxonomists to ecologists documenting historical records of invasive species. Our objective was to quantify the frequency of voucher specimen deposition in biodiversity and community ecology research through a survey of the peer-reviewed literature about arthropods, from 1989 until 2014. Overall rates of voucher deposition were alarmingly low, at under 25%. This rate increased significantly over time, with 35% of papers reporting on vouchers in 2014. Relative to the global mean, entomological research had a significantly higher rate of voucher deposition (46%), whereas researchers studying crustaceans deposited vouchers less than 6% of the time, significantly less than the mean. Researchers working in museums had a significantly higher frequency of voucher deposition. Our results suggest a significant culture shift about the process of vouchering specimens is required. There must be more education and mentoring about voucher specimens within laboratories and across different fields of study. Principal investigators and granting agencies need a proactive approach to ensuring specimen-level data are properly, long-term curated. Editorial boards and journals can also adopt policies to ensure papers are published only if explicit statements about the deposition of voucher specimens is provided. Although the gap is significant, achieving a higher rate of voucher specimen deposition is a worthy goal to ensure all research efforts are preserved for future generations. PMID:26339546

  19. Further use of nearly complete 28S and 18S rRNA genes to classify Ecdysozoa: 37 more arthropods and a kinorhynch.

    PubMed

    Mallatt, Jon; Giribet, Gonzalo

    2006-09-01

    This work expands on a study from 2004 by Mallatt, Garey, and Shultz [Mallatt, J.M., Garey, J.R., Shultz, J.W., 2004. Ecdysozoan phylogeny and Bayesian inference: first use of nearly complete 28S and 18S rRNA gene sequences to classify the arthropods and their kin. Mol. Phylogenet. Evol. 31, 178-191] that evaluated the phylogenetic relationships in Ecdysozoa (molting animals), especially arthropods. Here, the number of rRNA gene-sequences was effectively doubled for each major group of arthropods, and sequences from the phylum Kinorhyncha (mud dragons) were also included, bringing the number of ecdysozoan taxa to over 80. The methods emphasized maximum likelihood, Bayesian inference and statistical testing with parametric bootstrapping, but also included parsimony and minimum evolution. Prominent findings from our combined analysis of both genes are as follows. The fundamental subdivisions of Hexapoda (insects and relatives) are Insecta and Entognatha, with the latter consisting of collembolans (springtails) and a clade of proturans plus diplurans. Our rRNA-gene data provide the strongest evidence to date that the sister group of Hexapoda is Branchiopoda (fairy shrimps, tadpole shrimps, etc.), not Malacostraca. The large, Pancrustacea clade (hexapods within a paraphyletic Crustacea) divided into a few basic subclades: hexapods plus branchiopods; cirripedes (barnacles) plus malacostracans (lobsters, crabs, true shrimps, isopods, etc.); and the basally located clades of (a) ostracods (seed shrimps) and (b) branchiurans (fish lice) plus the bizarre pentastomids (tongue worms). These findings about Pancrustacea agree with a recent study by Regier, Shultz, and Kambic that used entirely different genes [Regier, J.C., Shultz, J.W., Kambic, R.E., 2005a. Pancrustacean phylogeny: hexapods are terrestrial crustaceans and maxillopods are not monophyletic. Proc. R. Soc. B 272, 395-401]. In Malacostraca, the stomatopod (mantis shrimp) was not at the base of the eumalacostracans

  20. Seasonal Distribution and Diversity of Ground Arthropods in Microhabitats Following a Shrub Plantation Age Sequence in Desertified Steppe

    PubMed Central

    Liu, Rentao; Zhu, Fan; Song, Naiping; Yang, Xinguo; Chai, Yongqing

    2013-01-01

    In desertified regions, shrub-dominated patches are important microhabitats for ground arthropod assemblages. As shrub age increases, soil, vegetation and microbiological properties can change remarkably and spontaneously across seasons. However, relatively few studies have analyzed how ground arthropods respond to the microhabitats created by shrubs of different plantation ages across seasons. Using 6, 15, 24 and 36 year-old plantations of re-vegetated shrubs (Caragana koushinskii) in the desert steppe of northwestern China as a model system, we sampled ground arthropod communities using a pitfall trapping method in the microhabitats under shrubs and in the open areas between shrubs, during the spring, summer and autumn. The total ground arthropod assemblage was dominated by Carabidae, Melolonthidae, Curculionidae, Tenebrionidae and Formicidae that were affected by plantation age, seasonal changes, or the interaction between these factors, with the later two groups also influenced by microhabitat. Overall, a facilitative effect was observed, with more arthropods and a greater diversity found under shrubs as compared to open areas, but this was markedly affected by seasonal changes. There was a high degree of similarity in arthropod assemblages and diversity between microhabitats in summer and autumn. Shrub plantation age significantly influenced the distribution of the most abundant groups, and also the diversity indices of the ground arthropods. However, there was not an overall positive relationship between shrub age and arthropod abundance, richness or diversity index. The influence of plantation age on arthropod communities was also affected by seasonal changes. From spring through summer to autumn, community indices of ground arthropods tended to decline, and a high degree of similarity in these indices (with fluctuation) was observed among different ages of shrub plantation in autumn. Altogether the recovery of arthropod communities was markedly affected by

  1. Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic

    PubMed Central

    Svobodová, Zdeňka; Skoková Habuštová, Oxana; Hutchison, William D.; Hussein, Hany M.; Sehnal, František

    2015-01-01

    Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009–2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G) and two non-Bt reference hybrids (KIPOUS and PR38N86). Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05). Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017) and non-Bt (DK315) untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability. PMID:26083254

  2. Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic.

    PubMed

    Svobodová, Zdeňka; Skoková Habuštová, Oxana; Hutchison, William D; Hussein, Hany M; Sehnal, František

    2015-01-01

    Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009-2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G) and two non-Bt reference hybrids (KIPOUS and PR38N86). Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05). Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017) and non-Bt (DK315) untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability. PMID:26083254

  3. Firmicutes dominate the bacterial taxa within sugar-cane processing plants.

    PubMed

    Sharmin, Farhana; Wakelin, Steve; Huygens, Flavia; Hargreaves, Megan

    2013-01-01

    Sugar cane processing sites are characterised by high sugar/hemicellulose levels, available moisture and warm conditions, and are relatively unexplored unique microbial environments. The PhyloChip microarray was used to investigate bacterial diversity and community composition in three Australian sugar cane processing plants. These ecosystems were highly complex and dominated by four main Phyla, Firmicutes (the most dominant), followed by Proteobacteria, Bacteroidetes, and Chloroflexi. Significant variation (p < 0.05) in community structure occurred between samples collected from 'floor dump sediment', 'cooling tower water', and 'bagasse leachate'. Many bacterial Classes contributed to these differences, however most were of low numerical abundance. Separation in community composition was also linked to Classes of Firmicutes, particularly Bacillales, Lactobacillales and Clostridiales, whose dominance is likely to be linked to their physiology as 'lactic acid bacteria', capable of fermenting the sugars present. This process may help displace other bacterial taxa, providing a competitive advantage for Firmicutes bacteria. PMID:24177592

  4. DNA barcoding and taxonomy: dark taxa and dark texts.

    PubMed

    Page, Roderic D M

    2016-09-01

    Both classical taxonomy and DNA barcoding are engaged in the task of digitizing the living world. Much of the taxonomic literature remains undigitized. The rise of open access publishing this century and the freeing of older literature from the shackles of copyright have greatly increased the online availability of taxonomic descriptions, but much of the literature of the mid- to late-twentieth century remains offline ('dark texts'). DNA barcoding is generating a wealth of computable data that in many ways are much easier to work with than classical taxonomic descriptions, but many of the sequences are not identified to species level. These 'dark taxa' hamper the classical method of integrating biodiversity data, using shared taxonomic names. Voucher specimens are a potential common currency of both the taxonomic literature and sequence databases, and could be used to help link names, literature and sequences. An obstacle to this approach is the lack of stable, resolvable specimen identifiers. The paper concludes with an appeal for a global 'digital dashboard' to assess the extent to which biodiversity data are available online.This article is part of the themed issue 'From DNA barcodes to biomes'. PMID:27481786

  5. Nested taxa-area curves for eastern United States floras

    USGS Publications Warehouse

    Bennett, J.P.

    1997-01-01

    The slopes of log-log species-area curves have been studied extensively and found to be influenced by the range of areas under study. Two such studies of eastern United States floras have yielded species-area curve slopes which differ by more than 100%: 0.251 and 0.113. The first slope may be too steep because the flora of the world was included, and both may be too steep because noncontiguous areas were used. These two hypotheses were tested using a set of nested floras centered in Ohio and continuing up to the flora of the world. The results suggest that this set of eastern United States floras produces a log-log species-area curve with a slope of approximately 0.20 with the flora of the world excluded, and regardless of whether or not the floras are from nested areas. Genera- and family-area curves are less steep than species-area curves and show similar patterns. Taxa ratio curves also increase with area, with the species/family ratio showing the steepest slope.

  6. Comparing mechanisms of host manipulation across host and parasite taxa

    USGS Publications Warehouse

    Lafferty, Kevin D.; Shaw, Jenny C.

    2013-01-01

    Parasites affect host behavior in several ways. They can alter activity, microhabitats or both. For trophically transmitted parasites (the focus of our study), decreased activity might impair the ability of hosts to respond to final-host predators, and increased activity and altered microhabitat choice might increase contact rates between hosts and final-host predators. In an analysis of trophically transmitted parasites, more parasite groups altered activity than altered microhabitat choice. Parasites that infected vertebrates were more likely to impair the host’s reaction to predators, whereas parasites that infected invertebrates were more likely to increase the host’s contact with predators. The site of infection might affect how parasites manipulate their hosts. For instance, parasites in the central nervous system seem particularly suited to manipulating host behavior. Manipulative parasites commonly occupy the body cavity, muscles and central nervous systems of their hosts. Acanthocephalans in the data set differed from other taxa in that they occurred exclusively in the body cavity of invertebrates. In addition, they were more likely to alter microhabitat choice than activity. Parasites in the body cavity (across parasite types) were more likely to be associated with increased host contact with predators. Parasites can manipulate the host through energetic drain, but most parasites use more sophisticated means. For instance, parasites target four physiological systems that shape behavior in both invertebrates and vertebrates: neural, endocrine, neuromodulatory and immunomodulatory. The interconnections between these systems make it difficult to isolate specific mechanisms of host behavioral manipulation.

  7. Biogeography of Heterotrophic Flagellate Populations Indicates the Presence of Generalist and Specialist Taxa in the Arctic Ocean

    PubMed Central

    Thaler, Mary

    2015-01-01

    Heterotrophic marine flagellates (HF) are ubiquitous in the world's oceans and represented in nearly all branches of the domain Eukaryota. However, the factors determining distributions of major taxonomic groups are poorly known. The Arctic Ocean is a good model environment for examining the distribution of functionally similar but phylogenetically diverse HF because the physical oceanography and annual ice cycles result in distinct environments that could select for microbial communities or favor specific taxa. We reanalyzed new and previously published high-throughput sequencing data from multiple studies in the Arctic Ocean to identify broad patterns in the distribution of individual taxa. HF accounted for fewer than 2% to over one-half of the reads from the water column and for up to 60% of reads from ice, which was dominated by Cryothecomonas. In the water column, many HF phylotypes belonging to Telonemia and Picozoa, uncultured marine stramenopiles (MAST), and choanoflagellates were geographically widely distributed. However, for two groups in particular, Telonemia and Cryothecomonas, some species level taxa showed more restricted distributions. For example, several phylotypes of Telonemia favored open waters with lower nutrients such as the Canada Basin and offshore of the Mackenzie Shelf. In summary, we found that while some Arctic HF were successful over a range of conditions, others could be specialists that occur under particular conditions. We conclude that tracking species level diversity in HF not only is feasible but also provides a potential tool for understanding the responses of marine microbial ecosystems to rapidly changing ice regimes. PMID:25595764

  8. Seasonal relationships between birds and arthropods in bottomland forest canopy gaps.

    SciTech Connect

    Bowen, Liessa, Thomas

    2004-12-31

    Bowen, Liessa, Thomas. 2004. Seasonal relationships between birds and arthropods in bottomland forest canopy gaps. PhD Dissertation. North Carolina State University. Raleigh, North Carolina. 98pp. I investigated the influence of arthropod availability and vegetation structure on avian habitat use at the center, edge, and adjacent to forest canopy gaps in 2001 and 2002. I used mist-netting and plot counts to estimate abundance of birds using three sizes (0.13, 0.26, and 0.5 ha) of 7-8 year old group-selection timber harvest openings during four seasons (spring migration, breeding, post-breeding, and fall migration) in a bottomland hardwood forest in the Upper Coastal Plain of South Carolina. I used foliage clipping, Malaise trapping, and pitfall trapping to determine arthropod abundance within each habitat, and I used a warm water crop-flush on captured birds to gather information about arthropods eaten. I observed more birds, including forest interior species, forest-edge spedge species, and several individual species, in early-successional canopy gap and gap-edge habitats than in surrounding mature forest during all seasons. I found a significant interaction between season and habitat type for several groups and individual species, suggesting a seasonal shift in habitat use. Captures of all birds, insectivorous birds, foliage- gleaners, ground-gleaners, aerial salliers, Hooded Warbler (Wilsonia citrina), Northern Cardinal (Cardinalis cardinalis), White-eyed Vireo (Vireo griseus), and Black-throated Blue Warbler (Dendroica caerulescens) were positively correlated with understory vegetation density during two or more seasons. I found relationships between insectivorous birds and leaf-dwelling Lepidoptera, insectivorous birds and ground-dwelling arthropods, foliage-gleaning birds and foliage-dwelling arthropods, and aerial salliers and flying arthropods, as well as between individual bird species and arthropods. Relationships were inconsistent, however, with many

  9. Spatial dynamics of understorey insectivorous birds and arthropods in a southeastern Brazilian Atlantic woodlot.

    PubMed

    Manhães, M A; Dias, M M

    2011-02-01

    Spatial distribution and spatial relationships in capture rates of understorey insectivorous birds and density of arthropods were investigated in a patch of upper montane rain forest in Minas Gerais state, southeastern Brazil, from January to December 2004. The composition of the arthropod fauna collected was similar to that reported for other tropical forests, with predominance of Araneae, Coleoptera, Hymenoptera and Hemiptera non-Heteroptera. A total of 26 bird species were captured, among which the more common were Dysithamnus mentalis, Conopophaga lineata, Platyrinchus mystaceus, Basileuterus culicivorus and Sclerurus scansor. Variation in the bird capture rates among sampling net lines were not correlated with arthropod density. Rather, individual analyses of some bird species suggest that spatial distribution of understorey insectivorous birds is better explained by habitat type. PMID:21437393

  10. Molecular methods for arthropod bloodmeal identification and applications to ecological and vector-borne disease studies.

    PubMed

    Kent, Rebekah J

    2009-01-01

    DNA-based methods have greatly enhanced the sensitivity and specificity of hematophagous arthropod bloodmeal identification. A variety of methods have been applied to study the blood-feeding behaviour of mosquitoes, ticks, black flies and other blood-feeding arthropods as it relates to host-parasite interactions and pathogen transmission. Overviews of the molecular techniques used for bloodmeal identification, their advantages, disadvantages and applications are presented for DNA sequencing, group-specific polymerase chain reaction primers, restriction fragment length polymorphism, real-time polymerase chain reaction, heteroduplex analysis, reverse line-blot hybridization and DNA profiling. Technical challenges to bloodmeal identification including digestion and analysis of mixed bloodmeals are discussed. Analysis of bloodmeal identification results remains a challenge to the field, particularly with regard to incorporation of vertebrate census and ecology data. Future research directions for molecular analysis of arthropod bloodmeals are proposed. PMID:21564560

  11. Preservation of three-dimensional anatomy in phosphatized fossil arthropods enriches evolutionary inference

    PubMed Central

    Schwermann, Achim H; dos Santos Rolo, Tomy; Caterino, Michael S; Bechly, Günter; Schmied, Heiko; Baumbach, Tilo; van de Kamp, Thomas

    2016-01-01

    External and internal morphological characters of extant and fossil organisms are crucial to establishing their systematic position, ecological role and evolutionary trends. The lack of internal characters and soft-tissue preservation in many arthropod fossils, however, impedes comprehensive phylogenetic analyses and species descriptions according to taxonomic standards for Recent organisms. We found well-preserved three-dimensional anatomy in mineralized arthropods from Paleogene fissure fillings and demonstrate the value of these fossils by utilizing digitally reconstructed anatomical structure of a hister beetle. The new anatomical data facilitate a refinement of the species diagnosis and allowed us to reject a previous hypothesis of close phylogenetic relationship to an extant congeneric species. Our findings suggest that mineralized fossils, even those of macroscopically poor preservation, constitute a rich but yet largely unexploited source of anatomical data for fossil arthropods. DOI: http://dx.doi.org/10.7554/eLife.12129.001 PMID:26854367

  12. Function and hydrostatics in the telson of the Burgess Shale arthropod Burgessia

    PubMed Central

    Lin, Jih-Pai

    2009-01-01

    Burgessia bella is a characteristic Burgess Shale arthropod (508 Ma), but the unusual preservation of its telson in both straight and bent modes leads to contradictory interpretations of its function. A reinvestigation of the fossil material, including burial attitudes, combined with a comparison with the decay sequence and mechanics of the telson in living Limulus, demonstrates that the telson of Burgessia was flexible in its relaxed state but could be stiffened in life. Evidence of fluid within the telson indicates that this manoeuvrability was achieved by changes in hydrostatic pressure and muscular control. The dual mode in the Burgessia telson is, to my knowledge, the first documented among fossil arthropods. It indicates that the requirement for a rigid telson, which is resolved by a thick sclerotized cuticle in most arthropods, may first have been achieved by hydrostatic means. PMID:19324649

  13. A framework for assessment and monitoring of arthropods in a lowland tropical forest.

    PubMed

    Finnamore, Albert; Alonso, Alfonso; Santisteban, Jose; Cordova, Saida; Valencia, Gorky; de la Cruz, Alicia; Polo, Roberto

    2002-05-01

    By applying principles of adaptive management, and by using the valuable information that arthropods provide from assessment and monitoring programs, managers can identify and reduce possible impacts on biodiversity in development projects. In 1996, the Smithsonian Institution's Monitoring and Assessment of Biodiversity program worked together with Shell Prospecting and Development Peru to establish an adaptive management program to protect biodiversity in a natural gas exploration project in a Peruvian rainforest. In this paper, we outlined the conceptual steps involved in establishing an assessment and monitoring program for arthropods, including setting objectives, evaluating the results and making decisions. We also present the results of the assessment using some of groups of arthropods, and summarize the steps taken to identify appropriate groups for monitoring. PMID:12125749

  14. Preservation of three-dimensional anatomy in phosphatized fossil arthropods enriches evolutionary inference.

    PubMed

    Schwermann, Achim H; Dos Santos Rolo, Tomy; Caterino, Michael S; Bechly, Günter; Schmied, Heiko; Baumbach, Tilo; van de Kamp, Thomas

    2016-01-01

    External and internal morphological characters of extant and fossil organisms are crucial to establishing their systematic position, ecological role and evolutionary trends. The lack of internal characters and soft-tissue preservation in many arthropod fossils, however, impedes comprehensive phylogenetic analyses and species descriptions according to taxonomic standards for Recent organisms. We found well-preserved three-dimensional anatomy in mineralized arthropods from Paleogene fissure fillings and demonstrate the value of these fossils by utilizing digitally reconstructed anatomical structure of a hister beetle. The new anatomical data facilitate a refinement of the species diagnosis and allowed us to reject a previous hypothesis of close phylogenetic relationship to an extant congeneric species. Our findings suggest that mineralized fossils, even those of macroscopically poor preservation, constitute a rich but yet largely unexploited source of anatomical data for fossil arthropods. PMID:26854367

  15. Elevated atmospheric CO2 alters the arthropod community in a forest understory

    NASA Astrophysics Data System (ADS)

    Hamilton, Jason; Zangerl, Arthur R.; Berenbaum, May R.; Sparks, Jed P.; Elich, Lauren; Eisenstein, Alissa; DeLucia, Evan H.

    2012-08-01

    The objective of this study was to determine the extent to which overall population sizes and community composition of arthropods in a naturally occurring forest understory are altered by elevated CO2. The Free Air Concentration Enrichment (FACE) method was used to fumigate large, replicated plots in the Piedmont region of North Carolina, USA to achieve the CO2 concentration predicted for 2050 (˜580 μl l-1). In addition, the extent to which unrestricted herbivorous arthropods were spatially delimited in their resource acquisition was determined. Stable isotope data for spiders (δ13C and δ15N) were collected in ambient and elevated CO2 plots and analyzed to determine whether their prey species moved among plots. Elevated CO2 had no effect on total arthropod numbers but had a large effect on the composition of the arthropod community. Insects collected in our samples were identified to a level that allowed for an assignment of trophic classification (generally to family). For the groups of insects sensitive to atmospheric gas composition, there was an increase in the numbers of individuals collected in primarily predaceous orders (Araneae and Hymenoptera; from 60% to more than 150%) under elevated CO2 and a decrease in the numbers in primarily herbivorous orders (Lepidoptera and Coleoptera; from -30 to -45%). Isotopic data gave no indication that the treatment plots represented a "boundary" to the movement of insects or that there were distinct and independent insect populations inside and outside the treatment plots. A simple two-ended mixing model estimates 55% of the carbon and nitrogen in spider biomass originated external to the elevated CO2 plots. In addition to changes in insect performance, decreases in herbivorous arthropods and increases in predaceous arthropods may also be factors involved in reduced herbivory under elevated CO2 in this forest.

  16. Habitat Heterogeneity Affects Plant and Arthropod Species Diversity and Turnover in Traditional Cornfields.

    PubMed

    Martínez, Eliana; Rös, Matthias; Bonilla, María Argenis; Dirzo, Rodolfo

    2015-01-01

    The expansion of the agricultural frontier by the clearing of remnant forests has led to human-dominated landscape mosaics. Previous studies have evaluated the effect of these landscape mosaics on arthropod diversity at local spatial scales in temperate and tropical regions, but little is known about fragmentation effects in crop systems, such as the complex tropical traditional crop systems that maintain a high diversity of weeds and arthropods in low-Andean regions. To understand the factors that influence patterns of diversity in human-dominated landscapes, we investigate the effect of land use types on plant and arthropod diversity in traditionally managed cornfields, via surveys of plants and arthropods in twelve traditional cornfields in the Colombian Andes. We estimated alpha and beta diversity to analyze changes in diversity related to land uses within a radius of 100 m to 1 km around each cornfield. We observed that forests influenced alpha diversity of plants, but not of arthropods. Agricultural lands had a positive relationship with plants and herbivores, but a negative relationship with predators. Pastures positively influenced the diversity of plants and arthropods. In addition, forest cover seemed to influence changes in plant species composition and species turnover of herbivore communities among cornfields. The dominant plant species varied among fields, resulting in high differentiation of plant communities. Predator communities also exhibited high turnover among cornfields, but differences in composition arose mainly among rare species. The crop system evaluated in this study represents a widespread situation in the tropics, therefore, our results can be of broad significance. Our findings suggest that traditional agriculture may not homogenize biological communities, but instead could maintain the regional pool of species through high beta diversity. PMID:26197473

  17. Habitat Heterogeneity Affects Plant and Arthropod Species Diversity and Turnover in Traditional Cornfields

    PubMed Central

    Martínez, Eliana; Rös, Matthias; Bonilla, María Argenis; Dirzo, Rodolfo

    2015-01-01

    The expansion of the agricultural frontier by the clearing of remnant forests has led to human-dominated landscape mosaics. Previous studies have evaluated the effect of these landscape mosaics on arthropod diversity at local spatial scales in temperate and tropical regions, but little is known about fragmentation effects in crop systems, such as the complex tropical traditional crop systems that maintain a high diversity of weeds and arthropods in low-Andean regions. To understand the factors that influence patterns of diversity in human-dominated landscapes, we investigate the effect of land use types on plant and arthropod diversity in traditionally managed cornfields, via surveys of plants and arthropods in twelve traditional cornfields in the Colombian Andes. We estimated alpha and beta diversity to analyze changes in diversity related to land uses within a radius of 100 m to 1 km around each cornfield. We observed that forests influenced alpha diversity of plants, but not of arthropods. Agricultural lands had a positive relationship with plants and herbivores, but a negative relationship with predators. Pastures positively influenced the diversity of plants and arthropods. In addition, forest cover seemed to influence changes in plant species composition and species turnover of herbivore communities among cornfields. The dominant plant species varied among fields, resulting in high differentiation of plant communities. Predator communities also exhibited high turnover among cornfields, but differences in composition arose mainly among rare species. The crop system evaluated in this study represents a widespread situation in the tropics, therefore, our results can be of broad significance. Our findings suggest that traditional agriculture may not homogenize biological communities, but instead could maintain the regional pool of species through high beta diversity. PMID:26197473

  18. Rapid mortality of pest arthropods by direct exposure to a dielectric barrier discharge

    NASA Astrophysics Data System (ADS)

    Bures, Brian Lee

    The spread of arthropods due to trade of agricultural commodities and travel of humans is a significant problem in many countries. Limiting the movement of pest species is commonly achieved by the use of chemical pesticides at quarantine facilities. One potential alternative to chemical pesticides is direct exposure of contaminated commodities to ambient pressure electrical discharges. The arthropods are directly exposed to a 5.0 cm helium discharge with power densities on the order of 60 mW/cm3. Direct measurement of chemical species and ambient gas temperature shows the DBD treatment remains effective when the chemically reactive species are suppressed by helium, and when the ambient gas temperature of the discharge is below 40°C. In addition to gas temperature measurements and chemical species identification, the electron temperature and electron density were measured using the neutral bremsstrahlung continuum technique. This study is the first successful implementation of the neutral bremsstrahlung continuum emission diagnostic to a barrier discharge. The primary advantages of the diagnostic for barrier discharges are the measurement is passive and the spatial resolution is only limited by the collimation of the light and the sensitivity of the detector. Although the electron temperature (1.0--1.5 eV) and electron density (˜108 cm-3) are modest, non-chemical dielectric barrier discharge (DBD) treatment of arthropods has proven effective in significantly reducing the population of some arthropods including human body lice, green peach aphids, and western flower thrips. However, the treatment was not universally effective on all arthropod species. German cockroaches and citrus mealy bugs showed substantial resistance to the treatment. The study has shown the treatment does not always induce instant mortality: however, the mortality increases over a 24 hr-period after treatment. Based upon visual observation and the time after treatment to reach maximum

  19. Deriving criteria to select arthropod species for laboratory tests to assess the ecological risks from cultivating transgenic crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arthropods form a major part of the biodiversity in agricultural landscapes. Many species are valued because they provide ecosystem services, including biological control, pollination, and decomposition, or because they are valued for cultural or economic reasons. Some arthropods reduce crop yield a...

  20. Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper provides recommendations on experimental design for early-tier laboratory studies used in the risk assessment process to evaluate potential adverse impacts of arthropod-resistant genetically-engineered plants on non-target arthropods. While we rely heavily on the currently used proteins f...

  1. Relationship between land use pattern and the structure and diversity of soil meso-micro arthropod community.

    PubMed

    Zhang, Limin; Zhang, Xueping; Cui, Wei

    2014-05-01

    Soil arthropod communities can provide valuable information regarding the impacts of human disturbances on ecosystem structure. Our study evaluated the structure, composition and diversity of soil meso-micro arthropod communities, in six different vegetation types and assessed the impacts of human activity. A completely randomized design, including 3 replicates from 6 sites (mowing steppe, natural grassland, severe degradation grassland, farmland, artificial shelter forest, and wetland) was used. Soil samples from the depth of 0 to 20 cm were collected during May, July, and September 2007. Soil meso-micro arthropod were separated using the Tullgren funnels method, and were identified and counted. Soil pH value, organic matter, and total nitrogen were measured in topsoil (0-20 cm) from each site. A total of 5,602 soil meso-micro arthropod individuals were collected, representing 4 classes, 14 orders, and 57 families. Most soil arthropods were widely distributed; however, some species appeared to be influenced by environment variables, and might serve as bioindicators of adverse human impacts. Canonical correspondence analysis indicated the soil arthropod distribution in the severely degraded grassland, mowing steppe, farmland, and shelter forest differed from the natural grassland. Arthropod density and diversity were greatest in May, and the forestland community was the most stable. Because of the vital role soil arthropods have in maintaining a healthy ecosystem, mechanisms to maintain their abundance and diversity should be further evaluated. PMID:24468921

  2. The diversity and abundance of small arthropods in onion, Allium cepa, seed crops, and their potential role in pollination.

    PubMed

    Walker, M K; Howlett, B G; Wallace, A R; McCallum, J A; Teulon, D A J

    2011-01-01

    Onion, Allium cepa L. (Asparagales: Amaryllidaceae), crop fields grown for seed production require arthropod pollination for adequate seed yield. Although many arthropod species visit A. cepa flowers, for most there is little information on their role as pollinators. Small flower visiting arthropods (body width < 3 mm) in particular are rarely assessed. A survey of eight flowering commercial A. cepa seed fields in the North and South Islands of New Zealand using window traps revealed that small arthropods were highly abundant among all except one field. Insects belonging to the orders Diptera and Thysanoptera were the most abundant and Hymenoptera, Collembola, Psocoptera, Hemiptera, and Coleoptera were also present. To test whether small arthropods might contribute to pollination, seed sets from umbels caged within 3 mm diameter mesh cages were compared with similarly caged, hand-pollinated umbels and uncaged umbels. Caged umbels that were not hand-pollinated set significantly fewer seeds (average eight seeds/umbel, n = 10) than caged hand-pollinated umbels (average 146 seeds/umbel) and uncaged umbels (average 481 seeds/umbel). Moreover, sticky traps placed on umbels within cages captured similar numbers of small arthropods as sticky traps placed on uncaged umbels, suggesting cages did not inhibit the movement of small arthropods to umbels. Therefore, despite the high abundance of small arthropods within fields, evidence to support their role as significant pollinators of commercial A. cepa seed crops was not found. PMID:22208869

  3. The Diversity and Abundance of Small Arthropods in Onion, Allium cepa, Seed Crops, and their Potential Role in Pollination

    PubMed Central

    Walker, M. K.; Howlett, B. G.; Wallace, A. R.; Mccallum, J. A.; Teulon, D. A. J.

    2011-01-01

    Onion, Allium cepa L. (Asparagales: Amaryllidaceae), crop fields grown for seed production require arthropod pollination for adequate seed yield. Although many arthropod species visit A. cepa flowers, for most there is little information on their role as pollinators. Small flower visiting arthropods (body width < 3 mm) in particular are rarely assessed. A survey of eight flowering commercial A. cepa seed fields in the North and South Islands of New Zealand using window traps revealed that small arthropods were highly abundant among all except one field. Insects belonging to the orders Diptera and Thysanoptera were the most abundant and Hymenoptera, Collembola, Psocoptera, Hemiptera, and Coleoptera were also present. To test whether small arthropods might contribute to pollination, seed sets from umbels caged within 3 mm diameter mesh cages were compared with similarly caged, hand-pollinated umbels and uncaged umbels. Caged umbels that were not hand-pollinated set significantly fewer seeds (average eight seeds/umbel, n = 10) than caged hand-pollinated umbels (average 146 seeds/umbel) and uncaged umbels (average 481 seeds/umbel). Moreover, sticky traps placed on umbels within cages captured similar numbers of small arthropods as sticky traps placed on uncaged umbels, suggesting cages did not inhibit the movement of small arthropods to umbels. Therefore, despite the high abundance of small arthropods within fields, evidence to support their role as significant pollinators of commercial A. cepa seed crops was not found. PMID:22208869

  4. Interference of boll weevil trapping by spiders (Araneida) and an evaluation of trap modification to reduce unwanted arthropods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our evaluation of a boll weevil trap modified to reduce the number of unwanted arthropods had little effect on reducing spiders, the arthropod species that made up > 95% of the individuals that entered boll weevil (Anthonomus grandis grandis Boheman) traps and interfere with weekly capture of boll w...

  5. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants

    PubMed Central

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

  6. The Multiple Impacts of Tropical Forest Fragmentation on Arthropod Biodiversity and on their Patterns of Interactions with Host Plants.

    PubMed

    Benítez-Malvido, Julieta; Dáttilo, Wesley; Martínez-Falcón, Ana Paola; Durán-Barrón, César; Valenzuela, Jorge; López, Sara; Lombera, Rafael

    2016-01-01

    Tropical rain forest fragmentation affects biotic interactions in distinct ways. Little is known, however, about how fragmentation affects animal trophic guilds and their patterns of interactions with host plants. In this study, we analyzed changes in biotic interactions in forest fragments by using a multitrophic approach. For this, we classified arthropods associated with Heliconia aurantiaca herbs into broad trophic guilds (omnivores, herbivores and predators) and assessed the topological structure of intrapopulation plant-arthropod networks in fragments and continuous forests. Habitat type influenced arthropod species abundance, diversity and composition with greater abundance in fragments but greater diversity in continuous forest. According to trophic guilds, coleopteran herbivores were more abundant in continuous forest and overall omnivores in fragments. Continuous forest showed a greater diversity of interactions than fragments. Only in fragments, however, did the arthropod community associated with H aurantiaca show a nested structure, suggesting novel and/or opportunistic host-arthropod associations. Plants, omnivores and predators contributed more to nestedness than herbivores. Therefore, Heliconia-arthropod network properties do not appear to be maintained in fragments mainly caused by the decrease of herbivores. Our study contributes to the understanding of the impact of fragmentation on the structure and dynamics of multitrophic arthropod communities associated with a particular plant species of the highly biodiverse tropical forests. Nevertheless, further replication of study sites is needed to strengthen the conclusion that forest fragmentation negatively affects arthropod assemblages. PMID:26731271

  7. [Alpha and beta arthropods diversity from the different environments of Parque Nacional Los Cardones, Salta, Argentina].

    PubMed

    Belén Cava, Maria; Antonio Corronca, José; José Echeverría, Alejandro

    2013-12-01

    The essential role of the National Parks is to protect nature, in order to prevent the deterioration and loss of the ecosystem under protection. Very few records about the diversity of arthropods are known from Los Cardones National Park, where three eco-regions are protected: Puna and Monte eco-regions and the High Andean Grassland of the Yungas. Here, we aimed to compare the alpha and beta diversity of arthropods in these eco-regions, and to prove if sites from the same ecoregion, show greater similarity between them in their assemblages, than with sites of the other eco-regions. We also identified arthropod orders with higher species richness, and indicated the families that contribute the most to the registered beta diversity. Three sampling sites were established on each eco-region and the arthropods were sampled using pitfall traps and suction samples. We evaluated the obtained inventory through nonparametric estimators of species richness, and compared diversity among eco-regions through "diversity profiles" and "effective number of species". Beta diversity was assessed by different methods such as the Morisita Index, nonmetric multidimentional scaling analysis, a multiple permutation procedure, and a Similarity Percentage analysis. We recorded 469 spp/morphospecies and recognized three arthropod orders (spiders, dipterans and hymenopterans) that are diverse and abundant in the Park. Besides, the diversity in Los Cardones National Park was found to be high, but it was observed higher in the High Andean Grassland of the Yungas, and lower in the Puna. The inventory obtained was good, reached up to the 81% of the species richness estimated by nonparametric estimators. Each eco-region of the park showed a very particular arthropod community that was tested by a multi-response permutation procedure. The species turnover between eco-regions was high, so that the different environments of the protected area are contributing to the maintenance of the regional

  8. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity

    PubMed Central

    Hertzog, Lionel R.; Meyer, Sebastian T.; Weisser, Wolfgang W.; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas

  9. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity.

    PubMed

    Hertzog, Lionel R; Meyer, Sebastian T; Weisser, Wolfgang W; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas

  10. Production of arthropod pests and vectors in coal strip mine ponds. Program report

    SciTech Connect

    Pickard, E.

    1981-06-01

    The objective of this study was to determine what species of medically important arthropods, particularly mosquitoes, are breeding in coal strip mine ponds, to what extent, and whether these breeding sites will serve as a focus of annoyance or a potential outbreak center of arthropod-borne diseases to surrounding communities. Pond age was compared with physical and chemical characteristics of the water and associated vegetation communities. Various sampling techniques were used to determine the composition and density of all life stages of the aquatic insect fauna.

  11. Onychophoran Hox genes and the evolution of arthropod Hox gene expression

    PubMed Central

    2014-01-01

    Introduction Onychophora is a relatively small phylum within Ecdysozoa, and is considered to be the sister group to Arthropoda. Compared to the arthropods, that have radiated into countless divergent forms, the onychophoran body plan is overall comparably simple and does not display much in-phylum variation. An important component of arthropod morphological diversity consists of variation of tagmosis, i.e. the grouping of segments into functional units (tagmata), and this in turn is correlated with differences in expression patterns of the Hox genes. How these genes are expressed in the simpler onychophorans, the subject of this paper, would therefore be of interest in understanding their subsequent evolution in the arthropods, especially if an argument can be made for the onychophoran system broadly reflecting the ancestral state in the arthropods. Results The sequences and embryonic expression patterns of the complete set of ten Hox genes of an onychophoran (Euperipatoides kanangrensis) are described for the first time. We find that they are all expressed in characteristic patterns that suggest a function as classical Hox genes. The onychophoran Hox genes obey spatial colinearity, and with the exception of Ultrabithorax (Ubx), they all have different and distinct anterior expression borders. Notably, Ubx transcripts form a posterior to anterior gradient in the onychophoran trunk. Expression of all onychophoran Hox genes extends continuously from their anterior border to the rear end of the embryo. Conclusions The spatial expression pattern of the onychophoran Hox genes may contribute to a combinatorial Hox code that is involved in giving each segment its identity. This patterning of segments in the uniform trunk, however, apparently predates the evolution of distinct segmental differences in external morphology seen in arthropods. The gradient-like expression of Ubx may give posterior segments their specific identity, even though they otherwise express the same

  12. Sustaining salmonid populations: A caring understanding of naturalness of taxa

    USGS Publications Warehouse

    Nielsen, J.L.; Regier, H.A.

    2004-01-01

    Species of the family of Salmonidae occur naturally in Northern Hemisphere waters that remain clear and cool to cold in summer. For purposes of reproduction, salmonids generally behaviorally respond to the currents of streams and lakes in recently glaciated areas. For feeding and maturation, many larger species migrate into existing systems of large lakes, seas, and oceans. The subfamilies include Salmoninae, Coregoninae, and Thymallinae. In many locales and regions of the hemisphere, numerous species of these subfamilies evolved and self-organized into species flocks or taxocenes of bewildering complexity. For example, any individual species may play different or unique ecological roles in different taxocenes. The northern Pacific and Atlantic Ocean ecosystems, with their seas and tributaries, each contained a metacomplex of such taxocenes that, in their natural state some centuries ago, resembled each other but differed in many ways. Humans have valued all species of this family for subsistence, ceremonial, naturalist, gustatory, angling, and commercial reasons for centuries. Modern progressive humans (MPHs), whose industrial and commercial enterprises have gradually spread over this hemisphere in recent time, now affect aquatic ecosystems at all scales from local to global. These human effects mingle in complex ways that together induce uniquely natural salmonid taxocenes to disintegrate with the loss of species, including those groups least tolerant to human manipulations, but extending more recently to those taxa more adapted to anthropogenic change. As we leave the modern era, dominated by MPHs, will we find ways to live sustainably with salmonid taxocenes that still exhibit self-organizational integrity, or will only individual, isolated populations of salmonid species, derived from those most tolerant of MPHs, survive? To achieve future sustainability of salmonids, we suggest implementation of a search for intuitive knowledge based on faith in the wisdom of

  13. Experimental infection of ectoparasitic arthropods with Rickettsia prowazekii (GvF-16 strain) and transmission to flying squirrels.

    PubMed

    Bozeman, F M; Sonenshine, D E; Williams, M S; Chadwick, D P; Lauer, D M; Elisberg, B L

    1981-01-01

    Epizootiologic studies conducted during the past few years showed the existence of widespread natural infection of the southern flying squirrel, Glaucomys volans, with epidemic typhus rickettsiae, Rickettsia prowazekii. The ecological findings strongly implicated transmission of the etiologic agent by an arthropod vector. Studies were conducted under controlled laboratory conditions to determine whether ectoparasites naturally associated with flying squirrels (squirrel fleas, lice, mites and ticks) were capable of acquiring, maintaining and transmitting the infection. Also studied were the cat flea, oriental rat flea and the human body louse. Flying squirrels inoculated with the GvF-16 strain of R. prowazekii circulated rickettsiae in their blood for 2-3 weeks, thus providing ample opportunity for arthropods feeding on them to become infected. The results with Dermacentor variabilis ticks indicated that the rickettsiae did not consistently survive in this insect and were not passed to the eggs of adult females that had been infected subcuticularly. Mites became infected by feeding on infectious blood but failed to sustain the infection. Also, mites fed on an infected flying squirrel did not transmit the infection to a normal squirrel. Squirrel, cat, and oriental rat fleas readily became infected by feeding on a rickettsemic host or on infectious blood through membranes, but failed to transmit the infection to susceptible flying squirrels. In the studies with flying squirrel lice, however, transmission of epidemic typhus from infected to uninfected flying squirrels was demonstrated. Infection of the human body louse with the GvF-16 flying squirrel strain of R. prowazekii was similar to that previously observed with classical human strains, viz., multiplication of the rickettsiae and excretion in the feces. PMID:6782900

  14. Production of arthropod pests and vectors in coal-strip-mine ponds

    SciTech Connect

    Pickard, E.

    1982-01-01

    The objective was to determine the species of aquatic arthropod pests, mainly mosquitoes, that were breeding in abandoned coal strip mine ponds, their population densities, and whether these breeding sites would serve as foci for annoyance to surrounding human populations. Nine study ponds were selected in Marion County, Alabama, on the basis of age since formation, with a total of three test ponds in each of three age categories: 1 year old, 5 years old, and 10 years old. These ponds were observed for five successive years; thus, data obtained from surveys depict successional changes in aquatic insect and plant species composition over a period of 14 successive years. Mosquito larvae of four genera including eight species were collected from the strip ponds. Mosquito production was not detected until ponds were at least two years old, and ponds five years old and older were the most productive for mosquitoes. Mosquito production in all ponds was sparse and restricted to narrow vegetated areas along shallow marginal shelves, and the level of mosquito activity was not sufficient to cause severe annoyance to surrounding communities. There was a paucity of insects of medical importance in benthic samples in the nine study ponds; only three genera of public health importance were collected, which consisted of Palpomyia, Chrysops, and Tabanus. Water chemistry of all ponds studied provided very favorable conditions for supporting various fauna and flora. Data obtained during the 5-year study showed no significant change in the pH of the water in the nine study ponds as they increased in age. The dissolved oxygen content of the water in the ponds varied widely with pond age and seasonal changes, ranging from 9.1 to 14.1 ppM.

  15. Regional differences in seasonal timing of rainfall discriminate between genetically distinct East African giraffe taxa.

    PubMed

    Thomassen, Henri A; Freedman, Adam H; Brown, David M; Buermann, Wolfgang; Jacobs, David K

    2013-01-01

    Masai (Giraffa tippelskirchi), Reticulated (G. reticulata) and Rothschild's (G. camelopardalis) giraffe lineages in East Africa are morphologically and genetically distinct, yet in Kenya their ranges abut. This raises the question of how divergence is maintained among populations of a large mammal capable of long-distance travel, and which readily hybridize in zoos. Here we test four hypotheses concerning the maintenance of the phylogeographic boundaries among the three taxa: 1) isolation-by-distance; 2) physical barriers to dispersal; 3) general habitat differences resulting in habitat segregation; or 4) regional differences in the seasonal timing of rainfall, and resultant timing of browse availability. We used satellite remotely sensed and climate data to characterize the environment at the locations of genotyped giraffes. Canonical variate analysis, random forest algorithms, and generalized dissimilarity modelling were employed in a landscape genetics framework to identify the predictor variables that best explained giraffes' genetic divergence. We found that regional differences in the timing of precipitation, and resulting green-up associated with the abundance of browse, effectively discriminate between taxa. Local habitat conditions, topographic and human-induced barriers, and geographic distance did not aid in discriminating among lineages. Our results suggest that selection associated with regional timing of events in the annual climatic cycle may help maintain genetic and phenotypic divergence in giraffes. We discuss potential mechanisms of maintaining divergence, and suggest that synchronization of reproduction with seasonal rainfall cycles that are geographically distinct may contribute to reproductive isolation. Coordination of weaning with green-up cycles could minimize the costs of lactation and predation on the young. Our findings are consistent with theory and empirical results demonstrating the efficacy of seasonal or phenologically dictated

  16. Diverse, rare microbial taxa responded to the Deepwater Horizon deep-sea hydrocarbon plume.

    PubMed

    Kleindienst, Sara; Grim, Sharon; Sogin, Mitchell; Bracco, Annalisa; Crespo-Medina, Melitza; Joye, Samantha B

    2016-02-01

    The Deepwater Horizon (DWH) oil well blowout generated an enormous plume of dispersed hydrocarbons that substantially altered the Gulf of Mexico's deep-sea microbial community. A significant enrichment of distinct microbial populations was observed, yet, little is known about the abundance and richness of specific microbial ecotypes involved in gas, oil and dispersant biodegradation in the wake of oil spills. Here, we document a previously unrecognized diversity of closely related taxa affiliating with Cycloclasticus, Colwellia and Oceanospirillaceae and describe their spatio-temporal distribution in the Gulf's deepwater, in close proximity to the discharge site and at increasing distance from it, before, during and after the discharge. A highly sensitive, computational method (oligotyping) applied to a data set generated from 454-tag pyrosequencing of bacterial 16S ribosomal RNA gene V4-V6 regions, enabled the detection of population dynamics at the sub-operational taxonomic unit level (0.2% sequence similarity). The biogeochemical signature of the deep-sea samples was assessed via total cell counts, concentrations of short-chain alkanes (C1-C5), nutrients, (colored) dissolved organic and inorganic carbon, as well as methane oxidation rates. Statistical analysis elucidated environmental factors that shaped ecologically relevant dynamics of oligotypes, which likely represent distinct ecotypes. Major hydrocarbon degraders, adapted to the slow-diffusive natural hydrocarbon seepage in the Gulf of Mexico, appeared unable to cope with the conditions encountered during the DWH spill or were outcompeted. In contrast, diverse, rare taxa increased rapidly in abundance, underscoring the importance of specialized sub-populations and potential ecotypes during massive deep-sea oil discharges and perhaps other large-scale perturbations. PMID:26230048

  17. Regional Differences in Seasonal Timing of Rainfall Discriminate between Genetically Distinct East African Giraffe Taxa

    PubMed Central

    Thomassen, Henri A.; Freedman, Adam H.; Brown, David M.; Buermann, Wolfgang; Jacobs, David K.

    2013-01-01

    Masai (Giraffa tippelskirchi), Reticulated (G. reticulata) and Rothschild's (G. camelopardalis) giraffe lineages in East Africa are morphologically and genetically distinct, yet in Kenya their ranges abut. This raises the question of how divergence is maintained among populations of a large mammal capable of long-distance travel, and which readily hybridize in zoos. Here we test four hypotheses concerning the maintenance of the phylogeographic boundaries among the three taxa: 1) isolation-by-distance; 2) physical barriers to dispersal; 3) general habitat differences resulting in habitat segregation; or 4) regional differences in the seasonal timing of rainfall, and resultant timing of browse availability. We used satellite remotely sensed and climate data to characterize the environment at the locations of genotyped giraffes. Canonical variate analysis, random forest algorithms, and generalized dissimilarity modelling were employed in a landscape genetics framework to identify the predictor variables that best explained giraffes' genetic divergence. We found that regional differences in the timing of precipitation, and resulting green-up associated with the abundance of browse, effectively discriminate between taxa. Local habitat conditions, topographic and human-induced barriers, and geographic distance did not aid in discriminating among lineages. Our results suggest that selection associated with regional timing of events in the annual climatic cycle may help maintain genetic and phenotypic divergence in giraffes. We discuss potential mechanisms of maintaining divergence, and suggest that synchronization of reproduction with seasonal rainfall cycles that are geographically distinct may contribute to reproductive isolation. Coordination of weaning with green-up cycles could minimize the costs of lactation and predation on the young. Our findings are consistent with theory and empirical results demonstrating the efficacy of seasonal or phenologically dictated

  18. Cambro-ordovician sea-level fluctuations and sequence boundaries: The missing record and the evolution of new taxa

    USGS Publications Warehouse

    Lehnert, O.; Miller, J.F.; Leslie, Stephen A.; Repetski, J.E.; Ethington, Raymond L.

    2005-01-01

    The evolution of early Palaeozoic conodont faunas shows a clear connection to sea-level changes. One way that this connection manifests itself is that thick successions of carbonates are missing beneath major sequence boundaries due to karstification and erosion. From this observation arises the question of how many taxa have been lost from different conodont lineages in these incomplete successions. Although many taxa suffered extinction due to the environmental stresses associated with falling sea-levels, some must have survived in these extreme conditions. The number of taxa missing in the early Palaeozoic tropics always will be unclear, but it will be even more difficult to evaluate the missing record in detrital successions of higher latitudes. A common pattern in the evolution of Cambrian-Ordovician conodont lineages is appearances of new species at sea-level rises and disappearances at sea-level drops. This simple picture can be complicated by intervals that consistently have no representatives of a particular lineage, even after extensive sampling of the most complete sections. Presumably the lineages survived in undocumented refugia. In this paper, we give examples of evolution in Cambrian-Ordovician shallowmarine conodont faunas and highlight problems of undiscovered or truly missing segments of lineages. ?? The Palaeontological Association.

  19. DNA barcode data accurately assign higher spider taxa.

    PubMed

    Coddington, Jonathan A; Agnarsson, Ingi; Cheng, Ren-Chung; Čandek, Klemen; Driskell, Amy; Frick, Holger; Gregorič, Matjaž; Kostanjšek, Rok; Kropf, Christian; Kweskin, Matthew; Lokovšek, Tjaša; Pipan, Miha; Vidergar, Nina; Kuntner, Matjaž

    2016-01-01

    The use of unique DNA sequences as a method for taxonomic identification is no longer fundamentally controversial, even though debate continues on the best markers, methods, and technology to use. Although both existing databanks such as GenBank and BOLD, as well as reference taxonomies, are imperfect, in best case scenarios "barcodes" (whether single or multiple, organelle or nuclear, loci) clearly are an increasingly fast and inexpensive method of identification, especially as compared to manual identification of unknowns by increasingly rare expert taxonomists. Because most species on Earth are undescribed, a complete reference database at the species level is impractical in the near term. The question therefore arises whether unidentified species can, using DNA barcodes, be accurately assigned to more inclusive groups such as genera and families-taxonomic ranks of putatively monophyletic groups for which the global inventory is more complete and stable. We used a carefully chosen test library of CO1 sequences from 49 families, 313 genera, and 816 species of spiders to assess the accuracy of genus and family-level assignment. We used BLAST queries of each sequence against the entire library and got the top ten hits. The percent sequence identity was reported from these hits (PIdent, range 75-100%). Accurate assignment of higher taxa (PIdent above which errors totaled less than 5%) occurred for genera at PIdent values >95 and families at PIdent values ≥ 91, suggesting these as heuristic thresholds for accurate generic and familial identifications in spiders. Accuracy of identification increases with numbers of species/genus and genera/family in the library; above five genera per family and fifteen species per genus all higher taxon assignments were correct. We propose that using percent sequence identity between conventional barcode sequences may be a feasible and reasonably accurate method to identify animals to family/genus. However, the quality of the

  20. DNA barcode data accurately assign higher spider taxa

    PubMed Central

    Coddington, Jonathan A.; Agnarsson, Ingi; Cheng, Ren-Chung; Čandek, Klemen; Driskell, Amy; Frick, Holger; Gregorič, Matjaž; Kostanjšek, Rok; Kropf, Christian; Kweskin, Matthew; Lokovšek, Tjaša; Pipan, Miha; Vidergar, Nina

    2016-01-01

    The use of unique DNA sequences as a method for taxonomic identification is no longer fundamentally controversial, even though debate continues on the best markers, methods, and technology to use. Although both existing databanks such as GenBank and BOLD, as well as reference taxonomies, are imperfect, in best case scenarios “barcodes” (whether single or multiple, organelle or nuclear, loci) clearly are an increasingly fast and inexpensive method of identification, especially as compared to manual identification of unknowns by increasingly rare expert taxonomists. Because most species on Earth are undescribed, a complete reference database at the species level is impractical in the near term. The question therefore arises whether unidentified species can, using DNA barcodes, be accurately assigned to more inclusive groups such as genera and families—taxonomic ranks of putatively monophyletic groups for which the global inventory is more complete and stable. We used a carefully chosen test library of CO1 sequences from 49 families, 313 genera, and 816 species of spiders to assess the accuracy of genus and family-level assignment. We used BLAST queries of each sequence against the entire library and got the top ten hits. The percent sequence identity was reported from these hits (PIdent, range 75–100%). Accurate assignment of higher taxa (PIdent above which errors totaled less than 5%) occurred for genera at PIdent values >95 and families at PIdent values ≥ 91, suggesting these as heuristic thresholds for accurate generic and familial identifications in spiders. Accuracy of identification increases with numbers of species/genus and genera/family in the library; above five genera per family and fifteen species per genus all higher taxon assignments were correct. We propose that using percent sequence identity between conventional barcode sequences may be a feasible and reasonably accurate method to identify animals to family/genus. However, the quality of

  1. NERISK: AN EXPERT SYSTEM TO ENHANCE THE INTEGRATION OF PESTICIDES WITH ARTHROPOD BIOLOGICAL CONTROL

    EPA Science Inventory

    An expert system termed NERISK was developed to evaluate the effects of pesticides on arthropod predators and parasitoids in a variety of agroecosystems. ased on a shell system (RECOG) with minor coding modifications, the system was designed to let even a novice user access the v...

  2. Water deficit stress - host plant nutrient accumulations and associations with phytophagous arthropods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to making otherwise arable regions less, or nonarable, from lack of life-sustaining water, water deficit also affects the extent to which crops are afflicted by arthropod pests. This chapter focuses on the effects of water deficit stress on physical and nutritional aspects of host plants...

  3. A Nod to disease vectors: mitigation of pathogen sensing by arthropod saliva

    PubMed Central

    Sakhon, Olivia S.; Severo, Maiara S.; Kotsyfakis, Michail; Pedra, Joao H. F.

    2013-01-01

    Arthropod saliva possesses anti-hemostatic, anesthetic, and anti-inflammatory properties that facilitate feeding and, inadvertently, dissemination of pathogens. Vector-borne diseases caused by these pathogens affect millions of people each year. Many studies address the impact of arthropod salivary proteins on various immunological components. However, whether and how arthropod saliva counters Nod-like (NLR) sensing remains elusive. NLRs are innate immune pattern recognition molecules involved in detecting microbial molecules and danger signals. Nod1/2 signaling results in activation of the nuclear factor-κB and the mitogen-activated protein kinase pathways. Caspase-1 NLRs regulate the inflammasome~– a protein scaffold that governs the maturation of interleukin (IL)-1β and IL-18. Recently, several vector-borne pathogens have been shown to induce NLR activation in immune cells. Here, we provide a brief overview of NLR signaling and discuss clinically relevant vector-borne pathogens recognized by NLR pathways. We also elaborate on possible anti-inflammatory effects of arthropod saliva on NLR signaling and microbial pathogenesis for the purpose of exchanging research perspectives. PMID:24155744

  4. Disparate effects of plant genotypic diversity on foliage and litter arthropod communities

    SciTech Connect

    Crutsinger, Greg; Reynolds, Nicholas; Classen, Aimee T; Sanders, Dr. Nathan James

    2008-01-01

    Intraspecific diversity within plant species is increasingly recognized as an important influence on the structure of associated arthropod communities, though whether there are congruent responses of above- and belowground communities to intraspecific diversity remains unclear. In this study, we compare the effects of host-plant genotype and genotypic diversity of the perennial plant, Solidago altissima, on the arthropod community associated with living plant tissue (foliage-based community) and microarthropods associated with leaf litter (litter-based community). We found that variation among host-plant genotypes had strong effects on the diversity and composition of foliage-based arthropods, but only weak influence on litter-based microarthropods. Furthermore, host-plant genotypic diversity was positively related to the abundance and diversity of foliage-based arthropods, including herbivore and predator trophic levels. In contrast, there were minimal effects of genotypic diversity in litter on microarthropods. Our study illustrates that incorporating both above- and belowground perspective into community genetics studies leads to very different conclusions about the importance of intraspecific diversity, than when considering aboveground responses in isolation.

  5. PRODUCTION OF ARTHROPOD PESTS AND VECTORS IN COAL STRIP MINE PONDS

    EPA Science Inventory

    The objective of this study was to determine what species of medically important arthropods, particularly mosquitoes, are breeding in coal strip mine ponds, to what extent, and whether these breeding sites will serve as a focus of annoyance or a potential outbreak center of arthr...

  6. Mini-aspirator: A new device for collection and transfer of small arthropods to plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The process of collecting and/or infesting plants with a designated number of small arthropods in biological experiments is tedious and laborious. We developed a modified mini-aspirator, powered with a vacuum pump and fitted with a specially adapted (removeable) collecting vial to reduce the handli...

  7. Reduced use of pesticides for effective controls of arthropod pests and plant diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current label recommendations of pesticides for arthropod pests and plant diseases in the nursery and green industry are vague and frequently result in excessive pesticide use. The objective of this research was to demonstrate that modifications of spray application techniques with existing spray eq...

  8. An overview of arthropod-associated fungi from Argentina and Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arthropod pests in forest and agricultural systems are afflicted by a plethora of pathogenic organisms. Among them, entomopathogenic fungi are the most common control agents that regulate their populations. This review compiles the information available from Argentina and Brazil about the entomopath...

  9. Francisella–Arthropod Vector Interaction and its Role in Patho-Adaptation to Infect Mammals

    PubMed Central

    Akimana, Christine; Kwaik, Yousef Abu

    2011-01-01

    Francisella tularensis is a Gram-negative, intracellular, zoonotic bacterium, and is the causative agent of tularemia with a broad host range. Arthropods such as ticks, mosquitoes, and flies maintain F. tularensis in nature by transmitting the bacteria among small mammals. While the tick is largely believed to be a biological vector of F. tularensis, transmission by mosquitoes and flies is largely believed to be mechanical on the mouthpart through interrupted feedings. However, the mechanism of infection of the vectors by F. tularensis is not well understood. Since F. tularensis has not been localized in the salivary gland of the primary human biting ticks, it is thought that bacterial transmission by ticks is through mechanical inoculation of tick feces containing F. tularensis into the skin wound. Drosophila melanogaster is an established good arthropod model for arthropod vectors of tularemia, where F. tularensis infects hemocytes, and is found in hemolymph, as seen in ticks. In addition, phagosome biogenesis and robust intracellular proliferation of F. tularensis in arthropod-derived cells are similar to that in mammalian macrophages. Furthermore, bacterial factors required for infectivity of mammals are often required for infectivity of the fly by F. tularensis. Several host factors that contribute to F. tularensis intracellular pathogenesis in D. melanogaster have been identified, and F. tularensis targets some of the evolutionarily conserved eukaryotic processes to enable intracellular survival and proliferation in evolutionarily distant hosts. PMID:21687425

  10. Vertical T-maze choice assay for arthropod response to odorants.

    PubMed

    Stelinski, Lukasz; Tiwari, Siddharth

    2013-01-01

    Given the economic importance of insects and arachnids as pests of agricultural crops, urban environments or as vectors of plant and human diseases, various technologies are being developed as control tools. A subset of these tools focuses on modifying the behavior of arthropods by attraction or repulsion. Therefore, arthropods are often the focus of behavioral investigations. Various tools have been developed to measure arthropod behavior, including wind tunnels, flight mills, servospheres, and various types of olfactometers. The purpose of these tools is to measure insect or arachnid response to visual or more often olfactory cues. The vertical T-maze olfactometer described here measures choices performed by insects in response to attractants or repellents. It is a high throughput assay device that takes advantage of the positive phototaxis (attraction to light) and negative geotaxis (tendency to walk or fly upward) exhibited by many arthropods. The olfactometer consists of a 30 cm glass tube that is divided in half with a Teflon strip forming a T-maze. Each half serves as an arm of the olfactometer enabling the test subjects to make a choice between two potential odor fields in assays involving attractants. In assays involving repellents, lack of normal response to known attractants can also be measured as a third variable. PMID:23439130

  11. Natural products from forest resources for use as arthropod and fungal biocides.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural products from Pacific Northwest forest resources can offer alternatives to the use of synthetic pesticides in the control of both arthropods of public health concern and forest fungal pathogens. Tree heartwood extracts with high toxicity (low LC50) in preliminary brine shrimp bioassays were...

  12. Natural Products from Forest Resources for Use as Arthropod and Fungal Biocides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural products from Pacific Northwest forest resources can offer alternatives to the use of synthetic pesticides in the control of both arthropods of public health concern and forest fungal pathogens. Tree heartwood extracts with high toxicity (low LC50) in preliminary brine shrimp bioassays were...

  13. Teaching Students about Biodiversity by Studying the Correlation between Plants & Arthropods

    ERIC Educational Resources Information Center

    Richardson, Matthew L.; Hari, Janice

    2008-01-01

    On Earth there is a huge diversity of arthropods, many of which are highly adaptive and able to exploit virtually every terrestrial habitat. Because of their prevalence even in urban environments, they make an excellent model system for any life science class. Since plants also exploit virtually every terrestrial habitat, studying the relationship…

  14. THE ROLE OF DEAD WOOD IN MAINTAINING ARTHROPOD DIVERSITY ON THE FOREST FLOOR.

    SciTech Connect

    Hanula, James L.; Horn, Scott; Wade, Dale D.

    2006-08-01

    Abstract—Dead wood is a major component of forests and contributes to overall diversity, primarily by supporting insects that feed directly on or in it. Further, a variety of organisms benefit by feeding on those insects. What is not well known is how or whether dead wood influences the composition of the arthropod community that is not solely dependent on it as a food resource, or whether woody debris influences prey available to generalist predators. One group likely to be affected by dead wood is ground-dwelling arthropods. We studied the effect of adding large dead wood to unburned and frequently burned pine stands to determine if dead wood was used more when the litter and understory plant community are removed. We also studied the effect of annual removal of dead wood from large (10-ha) plots over a 5-year period on ground-dwelling arthropods. In related studies, we examined the relationships among an endangered woodpecker that forages for prey on live trees, its prey, and dead wood in the forest. The results of these and other studies show that dead wood can influence the abundance and diversity of the ground-dwelling arthropod community and of prey available to generalist predators not foraging directly on dead trees.

  15. Selected examples of dispersal of arthropods associated with agricultural crop and animal production

    NASA Technical Reports Server (NTRS)

    Henneberry, T. J.

    1979-01-01

    The economic importance of arthropods in agricultural production systems and the possibilities of using dispersal behavior to develop and manipulate control are examined. Examples of long and short distance dispersal of economic insect pests and beneficial species from cool season host reservoirs and overwintering sites are presented. Significant dispersal of these species often occurring during crop and animal production is discussed.

  16. Relationships between dead wood and arthropods in the Southeastern United States.

    SciTech Connect

    Ulyshen, Michael, Darragh

    2009-05-01

    The importance of dead wood to maintaining forest diversity is now widely recognized. However, the habitat associations and sensitivities of many species associated with dead wood remain unknown, making it difficult to develop conservation plans for managed forests. The purpose of this research, conducted on the upper coastal plain of South Carolina, was to better understand the relationships between dead wood and arthropods in the southeastern United States. In a comparison of forest types, more beetle species emerged from logs collected in upland pine-dominated stands than in bottomland hardwood forests. This difference was most pronounced for Quercus nigra L., a species of tree uncommon in upland forests. In a comparison of wood postures, more beetle species emerged from logs than from snags, but a number of species appear to be dependent on snags including several canopy specialists. In a study of saproxylic beetle succession, species richness peaked within the first year of death and declined steadily thereafter. However, a number of species appear to be dependent on highly decayed logs, underscoring the importance of protecting wood at all stages of decay. In a study comparing litter-dwelling arthropod abundance at different distances from dead wood, arthropods were more abundant near dead wood than away from it. In another study, grounddwelling arthropods and saproxylic beetles were little affected by large-scale manipulations of dead wood in upland pine-dominated forests, possibly due to the suitability of the forests surrounding the plots.

  17. Assessment of Risk of Insect-resistant Transgenic Crops to Nontarget Arthropods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An international initiative is developing a scientifically rigorous approach to evaluate potential risks to non-target arthropods (NTA’s) posed by insect-resistant, genetically modified (IRGM) crops. It adapts the tiered approach to risk assessment that is accepted internationally within regulatory ...

  18. Biostable agonists that match or exceed activity of native insect kinins on recombinant arthropod GPCRs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The multifunctional arthropod insect kinins share the evolutionarily conserved C-terminal pentapeptide motif Phe-X1-X2-Trp-Gly-NH2, where X1 = His, Asn, Ser, or Tyr and X2 = Ser, Pro, or Ala. Insect kinins regulate diuresis in many species of insects. Compounds with similar biological activity cou...

  19. Characterization of the Arthropod Community Associated with Switchgrass (Poales: Poaceae) in Nebraska

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass (Panicum virgatum L.) is a perennial warm-season grass, native to the North American Great Plains. Recently, this prairie grass has received increased attention as a potential biomass energy crop. Little is known about the arthropod community affecting switchgrass grown under either mana...

  20. Plant Diversity Impacts Decomposition and Herbivory via Changes in Aboveground Arthropods

    PubMed Central

    Ebeling, Anne; Meyer, Sebastian T.; Abbas, Maike; Eisenhauer, Nico; Hillebrand, Helmut; Lange, Markus; Scherber, Christoph; Vogel, Anja; Weigelt, Alexandra; Weisser, Wolfgang W.

    2014-01-01

    Loss of plant diversity influences essential ecosystem processes as aboveground productivity, and can have cascading effects on the arthropod communities in adjacent trophic levels. However, few studies have examined how those changes in arthropod communities can have additional impacts on ecosystem processes caused by them (e.g. pollination, bioturbation, predation, decomposition, herbivory). Therefore, including arthropod effects in predictions of the impact of plant diversity loss on such ecosystem processes is an important but little studied piece of information. In a grassland biodiversity experiment, we addressed this gap by assessing aboveground decomposer and herbivore communities and linking their abundance and diversity to rates of decomposition and herbivory. Path analyses showed that increasing plant diversity led to higher abundance and diversity of decomposing arthropods through higher plant biomass. Higher species richness of decomposers, in turn, enhanced decomposition. Similarly, species-rich plant communities hosted a higher abundance and diversity of herbivores through elevated plant biomass and C:N ratio, leading to higher herbivory rates. Integrating trophic interactions into the study of biodiversity effects is required to understand the multiple pathways by which biodiversity affects ecosystem functioning. PMID:25226237

  1. Removing external DNA decontamination from arthropod predators destined for molecular gut-content analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molecular gut-content analysis enables detection of arthropod predation with minimal disruption of ecosystem processes. Field and laboratory experiments have demonstrated that mass-collection methods, such as sweep-netting, vacuum sampling, and foliage beating, can lead to contamination of fed pred...

  2. Resistance mechanisms against arthropod herbivores in cotton and their interactions with natural enemies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton plants from the genus Gossypium are grown on more than 30 million hectares worldwide and are a major source of fiber. The plants possess a wide-range of indirect and direct-defense mechanisms against arthropod pests. Direct defense mechanisms include morphological traits such as trichomes and...

  3. ASSESSING PESTICIDE RISK TO ARTHROPOD NATURAL ENEMIES USING EXPERT SYSTEM TECHNOLOGY

    EPA Science Inventory

    A prototype expert system (NERISK) has been developed to help users assess the impact of pesticides on beneficial arthropod predators and parasitoids in agricultural systems. hell program (RECOG) was adapted with minor modifications to allow the encoding of expert opinion on this...

  4. Removing external DNA contamination from arthropod predators destined for molecular gut-content analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molecular gut-content analysis enables detection of arthropod predation with minimal disruption of ecosystem processes. Field and laboratory experiments have demonstrated that mass-collection methods, such as sweep-netting, vacuum sampling, and foliage beating, can lead to contamination of fed pred...

  5. Natural carbon dioxide generation for the attraction of blood feeding arthropods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hematophagous arthropods are attracted to elevated carbon dioxide levels because it is closely associated with host blood meal availability. Bottled gas or frozen (dry ice) carbon dioxide are commonly used in surveillance programs and field collection techniques to increase the number of species and...

  6. Arthropod food web restoration following removal of an invasive wetland plant.

    PubMed

    Gratton, Claudio; Denno, Robert F

    2006-04-01

    Restoration of habitats impacted by invasive plants is becoming an increasingly important tool in the management of native biodiversity, though most studies do not go beyond monitoring the abundance of particular taxonomic groups, such as the return of native vegetation. Yet, the reestablishment of trophic interactions among organisms in restored habitats is equally important if we are to monitor and understand how ecosystems recover. This study examined whether food web interactions among arthropods (as inferred by abundance of naturally occurring stable isotopes of C [delta13C] and N [delta15N]) were reestablished in the restoration of a coastal Spartina alterniflora salt marsh that had been invaded by Phragmites australis. From patterns of C and N stable isotopes we infer that trophic interactions among arthropods in the native salt marsh habitats are characterized by reliance on the dominant marsh plant Spartina as a basal resource. Herbivores such as delphacid planthoppers and mirid bugs have isotope signatures characteristic of Spartina, and predatory arthropods such as dolicopodid flies and spiders likewise have delta13C and delta15N signatures typical of Spartina-derived resources (approximately -13 per thousand and 10 per thousand, respectively). Stable isotope patterns also suggest that the invasion of Phragmites into salt marshes and displacement of Spartina significantly alter arthropod food web interactions. Arthropods in Phragmites-dominated sites have delta13C isotope values between -18 per thousand and -20 per thousand, suggesting reliance on detritus and/or benthic microalgae as basal resources and not on Phragmites, which has a delta13C approximately -26 per thousand. Since most Phragmites herbivores are either feeding internally or are rare transients from nearby Spartina, these resources do not provide significant prey resources for other arthropod consumers. Rather, predator isotope signatures in the invaded habitats indicate dependence on

  7. The colonization of land by animals: molecular phylogeny and divergence times among arthropods

    PubMed Central

    Pisani, Davide; Poling, Laura L; Lyons-Weiler, Maureen; Hedges, S Blair

    2004-01-01

    Background The earliest fossil evidence of terrestrial animal activity is from the Ordovician, ~450 million years ago (Ma). However, there are earlier animal fossils, and most molecular clocks suggest a deep origin of animal phyla in the Precambrian, leaving open the possibility that animals colonized land much earlier than the Ordovician. To further investigate the time of colonization of land by animals, we sequenced two nuclear genes, glyceraldehyde-3-phosphate dehydrogenase and enolase, in representative arthropods and conducted phylogenetic and molecular clock analyses of those and other available DNA and protein sequence data. To assess the robustness of animal molecular clocks, we estimated the deuterostome-arthropod divergence using the arthropod fossil record for calibration and tunicate instead of vertebrate sequences to represent Deuterostomia. Nine nuclear and 15 mitochondrial genes were used in phylogenetic analyses and 61 genes were used in molecular clock analyses. Results Significant support was found for the unconventional pairing of myriapods (millipedes and centipedes) with chelicerates (spiders, scorpions, horseshoe crabs, etc.) using nuclear and mitochondrial genes. Our estimated time for the divergence of millipedes (Diplopoda) and centipedes (Chilopoda) was 442 ± 50 Ma, and the divergence of insects and crustaceans was estimated as 666 ± 58 Ma. Our results also agree with previous studies suggesting a deep divergence (~1100 – 900 Ma) for arthropods and deuterostomes, considerably predating the Cambrian Explosion seen in the animal fossil record. Conclusions The consistent support for a close relationship between myriapods and chelicerates, using mitochondrial and nuclear genes and different methods of analysis, suggests that this unexpected result is not an artefact of analysis. We propose the name Myriochelata for this group of animals, which includes many that immobilize prey with venom. Our molecular clock analyses using arthropod

  8. Registers of family-group and genus-group taxa of Aphidoidea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This “Register of the genus-group taxa of Aphidoidea” corresponds to the proposal approved by the delegates attending the Eighth International Symposium on Aphids with the addition of taxa described since 31 December 2005, the cutoff date for the proposal. The genus-group names included here belong...

  9. Employing citizen science to study defoliation impacts on arthropod communities on tamarisk

    NASA Astrophysics Data System (ADS)

    Kruse, Audrey L.

    The invasive tamarisk tree is widespread across the southwestern landscape of the United States and has been dominant in regulated river reaches, outcompeting native vegetation and impacting trophic webs in riparian ecosystems. The changes in riparian habitat and recreation opportunities along southwestern rivers, like the San Juan River in Utah, led to the implementation of a biocontrol program in the form of the tamarisk leaf beetle (Diorhabda spp.). It is unknown what the long term effects on riparian ecosystems are as a result of the beetles' defoliation of tamarisk each summer. This study sought to identify the current arthropod community composition and abundance over one growing season on the San Juan River between Bluff and Mexican Hat, UT and second, to involve the public in this research through a citizen science component. I found that non-native insects, including the tamarisk leaf beetle, dominated the arboreal arthropod communities within the tamarisk and there are relatively few native arthropods residing in tamarisk throughout the summer season. Foliation levels (the quantity of leaves in the canopy of tamarisk) were inconclusive predictors of arthropod abundances but varied by species and by feeding guild. This may indicate that the defoliation of the tamarisk is not necessarily negatively impacting trophic interactions in tamarisk. I incorporated youth participants on educational river rafting trips to assist in data collection of arthropods from tamarisk trees as a way to educate and bring attention to the issue of invasive species in the Southwest. After completing my own citizen science project and after doing a literature review of other, similar citizen science projects, I found that striving for both rigorous scientific data and quality educational programming is challenging for a small scale project that does not target broad spatial, geographic, or temporal data. Citizen science project developers should clearly identify their objectives

  10. The ABC gene family in arthropods: comparative genomics and role in insecticide transport and resistance.

    PubMed

    Dermauw, Wannes; Van Leeuwen, Thomas

    2014-02-01

    About a 100 years ago, the Drosophila white mutant marked the birth of Drosophila genetics. The white gene turned out to encode the first well studied ABC transporter in arthropods. The ABC gene family is now recognized as one of the largest transporter families in all kingdoms of life. The majority of ABC proteins function as primary-active transporters that bind and hydrolyze ATP while transporting a large diversity of substrates across lipid membranes. Although extremely well studied in vertebrates for their role in drug resistance, less is known about the role of this family in the transport of endogenous and exogenous substances in arthropods. The ABC families of five insect species, a crustacean and a chelicerate have been annotated in some detail. We conducted a thorough phylogenetic analysis of the seven arthropod and human ABC protein subfamilies, to infer orthologous relationships that might suggest conserved function. Most orthologous relationships were found in the ABCB half transporter, ABCD, ABCE and ABCF subfamilies, but specific expansions within species and lineages are frequently observed and discussed. We next surveyed the role of ABC transporters in the transport of xenobiotics/plant allelochemicals and their involvement in insecticide resistance. The involvement of ABC transporters in xenobiotic resistance in arthropods is historically not well documented, but an increasing number of studies using unbiased differential gene expression analysis now points to their importance. We give an overview of methods that can be used to link ABC transporters to resistance. ABC proteins have also recently been implicated in the mode of action and resistance to Bt toxins in Lepidoptera. Given the enormous interest in Bt toxicology in transgenic crops, such findings will provide an impetus to further reveal the role of ABC transporters in arthropods. PMID:24291285

  11. Immunolocalization of serotonin in Onychophora argues against segmental ganglia being an ancestral feature of arthropods

    PubMed Central

    Mayer, Georg; Harzsch, Steffen

    2007-01-01

    Background Onychophora (velvet worms) represent the most basal arthropod group and play a pivotal role in the current discussion on the evolution of nervous systems and segmentation in arthropods. Although there is a wealth of information on the immunolocalization of serotonin (5-hydroxytryptamine, 5-HT) in various euarthropods, as yet no comparable localization data are available for Onychophora. In order to understand how the onychophoran nervous system compares to that of other arthropods, we studied the distribution of serotonin-like immunoreactive neurons and histological characteristics of ventral nerve cords in Metaperipatus blainvillei (Onychophora, Peripatopsidae) and Epiperipatus biolleyi (Onychophora, Peripatidae). Results We demonstrate that paired leg nerves are the only segmental structures associated with the onychophoran nerve cord. Although the median commissures and peripheral nerves show a repeated pattern, their arrangement is independent from body segments characterized by the position of legs and associated structures. Moreover, the somata of serotonin-like immunoreactive neurons do not show any ordered arrangement in both species studied but are instead scattered throughout the entire length of each nerve cord. We observed neither a serially iterated nor a bilaterally symmetric pattern, which is in contrast to the strictly segmental arrangement of serotonergic neurons in other arthropods. Conclusion Our histological findings and immunolocalization experiments highlight the medullary organization of the onychophoran nerve cord and argue against segmental ganglia of the typical euarthropodan type being an ancestral feature of Onychophora. These results contradict a priori assumptions of segmental ganglia being an ancestral feature of arthropods and, thus, weaken the traditional Articulata hypothesis, which proposes a sistergroup relationship of Annelida and Arthropoda. PMID:17629937

  12. Comparative Genomics Reveals the Origins and Diversity of Arthropod Immune Systems.

    PubMed

    Palmer, William J; Jiggins, Francis M

    2015-08-01

    Insects are an important model for the study of innate immune systems, but remarkably little is known about the immune system of other arthropod groups despite their importance as disease vectors, pests, and components of biological diversity. Using comparative genomics, we have characterized the immune system of all the major groups of arthropods beyond insects for the first time--studying five chelicerates, a myriapod, and a crustacean. We found clear traces of an ancient origin of innate immunity, with some arthropods having Toll-like receptors and C3-complement factors that are more closely related in sequence or structure to vertebrates than other arthropods. Across the arthropods some components of the immune system, such as the Toll signaling pathway, are highly conserved. However, there is also remarkable diversity. The chelicerates apparently lack the Imd signaling pathway and beta-1,3 glucan binding proteins--a key class of pathogen recognition receptors. Many genes have large copy number variation across species, and this may sometimes be accompanied by changes in function. For example, we find that peptidoglycan recognition proteins have frequently lost their catalytic activity and switch between secreted and intracellular forms. We also find that there has been widespread and extensive duplication of the cellular immune receptor Dscam (Down syndrome cell adhesion molecule), which may be an alternative way to generate the high diversity produced by alternative splicing in insects. In the antiviral short interfering RNAi pathway Argonaute 2 evolves rapidly and is frequently duplicated, with a highly variable copy number. Our results provide a detailed analysis of the immune systems of several important groups of animals for the first time and lay the foundations for functional work on these groups. PMID:25908671

  13. Comparative Genomics Reveals the Origins and Diversity of Arthropod Immune Systems

    PubMed Central

    Palmer, William J.; Jiggins, Francis M.

    2015-01-01

    Insects are an important model for the study of innate immune systems, but remarkably little is known about the immune system of other arthropod groups despite their importance as disease vectors, pests, and components of biological diversity. Using comparative genomics, we have characterized the immune system of all the major groups of arthropods beyond insects for the first time—studying five chelicerates, a myriapod, and a crustacean. We found clear traces of an ancient origin of innate immunity, with some arthropods having Toll-like receptors and C3-complement factors that are more closely related in sequence or structure to vertebrates than other arthropods. Across the arthropods some components of the immune system, such as the Toll signaling pathway, are highly conserved. However, there is also remarkable diversity. The chelicerates apparently lack the Imd signaling pathway and beta-1,3 glucan binding proteins—a key class of pathogen recognition receptors. Many genes have large copy number variation across species, and this may sometimes be accompanied by changes in function. For example, we find that peptidoglycan recognition proteins have frequently lost their catalytic activity and switch between secreted and intracellular forms. We also find that there has been widespread and extensive duplication of the cellular immune receptor Dscam (Down syndrome cell adhesion molecule), which may be an alternative way to generate the high diversity produced by alternative splicing in insects. In the antiviral short interfering RNAi pathway Argonaute 2 evolves rapidly and is frequently duplicated, with a highly variable copy number. Our results provide a detailed analysis of the immune systems of several important groups of animals for the first time and lay the foundations for functional work on these groups. PMID:25908671

  14. Tyrosine Detoxification Is an Essential Trait in the Life History of Blood-Feeding Arthropods.

    PubMed

    Sterkel, Marcos; Perdomo, Hugo D; Guizzo, Melina G; Barletta, Ana Beatriz F; Nunes, Rodrigo D; Dias, Felipe A; Sorgine, Marcos H F; Oliveira, Pedro L

    2016-08-22

    Blood-feeding arthropods are vectors of infectious diseases such as dengue, Zika, Chagas disease, and malaria [1], and vector control is essential to limiting disease spread. Because these arthropods ingest very large amounts of blood, a protein-rich meal, huge amounts of amino acids are produced during digestion. Previous work on Rhodnius prolixus, a vector of Chagas disease, showed that, among all amino acids, only tyrosine degradation enzymes were overexpressed in the midgut compared to other tissues [2]. Here we demonstrate that tyrosine detoxification is an essential trait in the life history of blood-sucking arthropods. We found that silencing Rhodnius tyrosine aminotransferase (TAT) and 4-hydroxyphenylpyruvate dioxygenase (HPPD), the first two enzymes of the phenylalanine/tyrosine degradation pathway, caused the death of insects after a blood meal. This was confirmed by using the HPPD inhibitor mesotrione, which selectively killed hematophagous arthropods but did not affect non-hematophagous insects. In addition, mosquitoes and kissing bugs died after feeding on mice that had previously received a therapeutic effective oral dose (1 mg/kg) of nitisinone, another HPPD inhibitor used in humans for the treatment of tyrosinemia type I [3]. These findings indicate that HPPD (and TAT) can be a target for the selective control of blood-sucking disease vector populations. Because HPPD inhibitors are extensively used as herbicides and in medicine, these compounds may provide an alternative less toxic to humans and more environmentally friendly than the conventional neurotoxic insecticides that are currently used, with the ability to affect only hematophagous arthropods. PMID:27476595

  15. Arthropod prey for riparian associated birds in headwater forests of the Oregon Coast Range

    USGS Publications Warehouse

    Hagar, Joan C.; Li, Judith; Sobota, Janel; Jenkins, Stephanie

    2012-01-01

    Headwater riparian areas occupy a large proportion of the land base in Pacific Northwest forests, and thus are ecologically and economically important. Although a primary goal of management along small headwater streams is the protection of aquatic resources, streamside habitat also is important for many terrestrial wildlife species. However, mechanisms underlying the riparian associations of some terrestrial species have not been well studied, particularly for headwater drainages. We investigated the diets of and food availability for four bird species associated with riparian habitats in montane coastal forests of western Oregon, USA. We examined variation in the availability of arthropod prey as a function of distance from stream. Specifically, we tested the hypotheses that (1) emergent aquatic insects were a food source for insectivorous birds in headwater riparian areas, and (2) the abundances of aquatic and terrestrial arthropod prey did not differ between streamside and upland areas during the bird breeding season. We found that although adult aquatic insects were available for consumption throughout the study period, they represented a relatively small proportion of available prey abundance and biomass and were present in only 1% of the diet samples from only one of the four riparian-associated bird species. Nonetheless, arthropod prey, comprised primarily of insects of terrestrial origin, was more abundant in streamside than upland samples. We conclude that food resources for birds in headwater riparian areas are primarily associated with terrestrial vegetation, and that bird distributions along the gradient from streamside to upland may be related to variation in arthropod prey availability. Because distinct vegetation may distinguish riparian from upland habitats for riparian-associated birds and their terrestrial arthropod prey, we suggest that understory communities be considered when defining management zones for riparian habitat.

  16. Impact of Location, Cropping History, Tillage, and Chlorpyrifos on Soil Arthropods in Peanut.

    PubMed

    Cardoza, Yasmin J; Drake, Wendy L; Jordan, David L; Schroeder-Moreno, Michelle S; Arellano, Consuelo; Brandenburg, Rick L

    2015-08-01

    Demand for agricultural production systems that are both economically viable and environmentally conscious continues to increase. In recent years, reduced tillage systems, and grass and pasture rotations have been investigated to help maintain or improve soil quality, increase crop yield, and decrease labor requirements for production. However, documentation of the effects of reduced tillage, fescue rotation systems as well as other management practices, including pesticides, on pest damage and soil arthropod activity in peanut production for the Mid-Atlantic US region is still limited. Therefore, this project was implemented to assess impacts of fescue-based rotation systems on pests and other soil organisms when compared with cash crop rotation systems over four locations in eastern North Carolina. In addition, the effects of tillage (strip vs. conventional) and soil chlorpyrifos application on pod damage and soil-dwelling organisms were also evaluated. Soil arthropod populations were assessed by deploying pitfall traps containing 50% ethanol in each of the sampled plots. Results from the present study provide evidence that location significantly impacts pest damage and soil arthropod diversity in peanut fields. Cropping history also influenced arthropod diversity, with higher diversity in fescue compared with cash crop fields. Corn rootworm damage to pods was higher at one of our locations (Rocky Mount) compared with all others. Cropping history (fescue vs. cash crop) did not have an effect on rootworm damage, but increased numbers of hymenopterans, acarina, heteropterans, and collembolans in fescue compared with cash crop fields. Interestingly, there was an overall tendency for higher number of soil arthropods in traps placed in chlorpyrifos-treated plots compared with nontreated controls. PMID:26314040

  17. Vouchering DNA Barcoding Specimens: Test of a Non-Destructive Extraction Protocol for Arthropods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The correct identification of species is essential to the performance of ecological research. Morphology-based keys support accurate identification of many taxa. However, for taxa that are not well studied, or for which distinguishing morphological characters have not been discerned, identification ...

  18. Targeting arthropod subolesin/akirin for the development of a universal vaccine for control of vector infestations and pathogen transmission.

    PubMed

    de la Fuente, José; Moreno-Cid, Juan A; Canales, Mario; Villar, Margarita; de la Lastra, José M Pérez; Kocan, Katherine M; Galindo, Ruth C; Almazán, Consuelo; Blouin, Edmour F

    2011-09-01

    Diseases caused by arthropod-borne pathogens greatly impact on human and animal health. Recent research has provided evidence that tick protective antigens can be used for development of vaccines with the dual target of controlling arthropod infestations and reducing their vector capacity for pathogens. As reviewed herein, protective antigens such as subolesin/akirin, which are highly conserved across vector species, show promise for use in development of a universal vaccine for the control of arthropod infestations and the reduction of pathogen transmission. However, further research is needed in critical areas towards achieving this goal. PMID:21561715

  19. Assessment of available anatomical characters for linking living mammals to fossil taxa in phylogenetic analyses

    PubMed Central

    2016-01-01

    Analyses of living and fossil taxa are crucial for understanding biodiversity through time. The total evidence method allows living and fossil taxa to be combined in phylogenies, using molecular data for living taxa and morphological data for living and fossil taxa. With this method, substantial overlap of coded anatomical characters among living and fossil taxa is vital for accurately inferring topology. However, although molecular data for living species are widely available, scientists generating morphological data mainly focus on fossils. Therefore, there are fewer coded anatomical characters in living taxa, even in well-studied groups such as mammals. We investigated the number of coded anatomical characters available in phylogenetic matrices for living mammals and how these were phylogenetically distributed across orders. Eleven of 28 mammalian orders have less than 25% species with available characters; this has implications for the accurate placement of fossils, although the issue is less pronounced at higher taxonomic levels. In most orders, species with available characters are randomly distributed across the phylogeny, which may reduce the impact of the problem. We suggest that increased morphological data collection efforts for living taxa are needed to produce accurate total evidence phylogenies. PMID:27146442

  20. Assessment of available anatomical characters for linking living mammals to fossil taxa in phylogenetic analyses.

    PubMed

    Guillerme, Thomas; Cooper, Natalie

    2016-05-01

    Analyses of living and fossil taxa are crucial for understanding biodiversity through time. The total evidence method allows living and fossil taxa to be combined in phylogenies, using molecular data for living taxa and morphological data for living and fossil taxa. With this method, substantial overlap of coded anatomical characters among living and fossil taxa is vital for accurately inferring topology. However, although molecular data for living species are widely available, scientists generating morphological data mainly focus on fossils. Therefore, there are fewer coded anatomical characters in living taxa, even in well-studied groups such as mammals. We investigated the number of coded anatomical characters available in phylogenetic matrices for living mammals and how these were phylogenetically distributed across orders. Eleven of 28 mammalian orders have less than 25% species with available characters; this has implications for the accurate placement of fossils, although the issue is less pronounced at higher taxonomic levels. In most orders, species with available characters are randomly distributed across the phylogeny, which may reduce the impact of the problem. We suggest that increased morphological data collection efforts for living taxa are needed to produce accurate total evidence phylogenies. PMID:27146442

  1. SEM characterization of anatomical variation in chitin organization in insect and arthropod cuticles.

    PubMed

    Chandran, Rakkiyappan; Williams, Lee; Hung, Albert; Nowlin, Kyle; LaJeunesse, Dennis

    2016-03-01

    The cuticles of insects and arthropods have some of the most diverse material properties observed in nature, so much so that it is difficult to imagine that all cutciles are primarily composed of the same two materials: a fibrous chitin network and a matrix composed of cuticle proteins. Various factors contribute to the mechanical and optical properties of an insect or arthropod cuticle including the thickness and composition. In this paper, we also identified another factor that may contribute to the optical, surface, and mechanical properties of a cuticle, i.e. the organization of chitin nanofibers and chitin fiber bundles. Self-assembled chitin nanofibers serve as the foundation for all higher order chitin structures in the cuticles of insects and other arthropods via interactions with structural cuticle proteins. Using a technique that enables the characterization of chitin organization in the cuticle of intact insects and arthropod exoskeletons, we demonstrate a structure/function correlation of chitin organization with larger scale anatomical structures. The chitin scaffolds in cuticles display an extraordinarily diverse set of morphologies that may reflect specific mechanical or physical properties. After removal of the proteinaceous and mineral matrix of a cuticle, we observe using SEM diverse nanoscale and micro scale organization of in-situ chitin in the wing, head, eye, leg, and dorsal and ventral thoracic regions of the periodical cicada Magicicada septendecim and in other insects and arthropods. The organization of chitin also appears to have a significant role in the organization of nanoscale surface structures. While microscale bristles and hairs have long been known to be chitin based materials formed as cellular extensions, we have found a nanostructured layer of chitin in the cuticle of the wing of the dog day annual cicada Tibicen tibicens, which may be the scaffold for the nanocone arrays found on the wing. We also use this process to examine

  2. Asexual Endophytes and Associated Alkaloids Alter Arthropod Community Structure and Increase Herbivore Abundances on a Native Grass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dispite their minute biomass, microbial symbionts of plants potentially alter herbivory, diversity and community structure. Infection of grasses by asexual endophytic fungi often decreases herbivore loads and alters arthropod diverisy. However, most studies to date have involved agronomic grasses ...

  3. Mineral cycling in soil and litter arthropod food chains. Progress report, November 1, 1979-October 31, 1980

    SciTech Connect

    Crossley, Jr, D A

    1980-08-01

    Recent progress and current status are reported for research concerned with mineral element dynamics in soil arthropod food chains. Research is performed within the larger context of terrestrial decomposition systems, in which soil arthropods may act as regulators of nutrient dynamics during decomposition. Research is measuring rates of nutrient accumulation and excretion by using radioactive tracer techniques with radioactive analogs of nutrients. Experimental measurement of radioactive tracer excretion and nutrient element pools are reported for soil microarthropods, using new methods of counting and microprobe elemental analysis. Research on arthropod-fungal relations is utilizing high-efficiency extraction followed by dissection of 13 x 13 cm soil blocks. A two-component excretion model is reported for Cobalt-60 in earthworms (Eisenia foetida), demonstrating that no assimilation of cobalt occurs from the mineral soil fraction but is entirely from organic matter. Collection of data sets on soil arthropod communities and abundances is completed.

  4. Comparative studies on the effects of Bt-transgenic and nontransgenic cotton on arthropod diversity, seedcotton yield and bollworms control.

    PubMed

    Dhillon, M K; Sharma, H C

    2013-01-01

    The effectiveness of commercial Bt-cotton in pest management, influence on arthropod diversity, natural enemies, and toxin flow in the insect fauna under field conditions were studied keeping in view the need to assess bioefficacy and biosafety of Bt-transgenic cotton. There were no significant differences in oviposition by Helicoverpa armigera on Bt-transgenic and non-transgenic cottons (9.2 versus 9.6 eggs plants(-100)), while the numbers of H. armigera larvae were significantly more on non-transgenic than on Bt-transgenic (10.4 versus 4.0 larvae plants(-100)) cotton. The Bt-cotton had significantly more number of mature opened bolls (9.6 versus 4.4 bolls plant(-1)), lower bollworm damage (12.8 versus 40.2% bolls damaged), and higher seedcotton yield (667.7 versus 231.7 kg ha 1). Population of cotton leafhopper, Amrasca biguttula biguttula was lower (582.2 versus 732.2 leafhoppers plants(-100)), while that of whitefly, Bemisia tabaci was higher on Bt-transgenic (65.2 versus 45.6 whiteflies plants(-100)) than on non-transgenic cotton. There was no significant influence of Bt-transgenic cotton on abundance of natural enemies of crop pests - chrysopids (9.6 versus 8.4 chrysopids plants(-100), ladybird beetles (16.0 versus 10.8 ladybirds plants(-100)), and spiders (128.4 versus 142.8 spiders plants(-100)). There were no significant differences in H. ormigera egg (19.8 versus 20.9%), larval (7.4 versus 9.6%), and larval-pupal (1.3 versus 2.9%) parasitism on Bt-transgenic and non-transgenic cottons in the farmer's fields. The parasitism in larvae of H. armigera was far lower than that of the eggs, which might be because of early mortality of H. armigera prior to parasitoid development in the host larvae. Although, Cry1Ac Bt toxin was detected in Cheilomenes sexmoculatus, chrysopids, A. bigutulla bigutulla, Thrips taboci, Myllocerus sp., Oxycarenus laetus, Dysdercus koenigii, spiders, bugs, and grasshoppers, no significant differences were observed in their abundance on

  5. Non-Structural Proteins of Arthropod-Borne Bunyaviruses: Roles and Functions

    PubMed Central

    Eifan, Saleh; Schnettler, Esther; Dietrich, Isabelle; Kohl, Alain; Blomström, Anne-Lie

    2013-01-01

    Viruses within the Bunyaviridae family are tri-segmented, negative-stranded RNA viruses. The family includes several emerging and re-emerging viruses of humans, animals and plants, such as Rift Valley fever virus, Crimean-Congo hemorrhagic fever virus, La Crosse virus, Schmallenberg virus and tomato spotted wilt virus. Many bunyaviruses are arthropod-borne, so-called arboviruses. Depending on the genus, bunyaviruses encode, in addition to the RNA-dependent RNA polymerase and the different structural proteins, one or several non-structural proteins. These non-structural proteins are not always essential for virus growth and replication but can play an important role in viral pathogenesis through their interaction with the host innate immune system. In this review, we will summarize current knowledge and understanding of insect-borne bunyavirus non-structural protein function(s) in vertebrate, plant and arthropod. PMID:24100888

  6. [What gene and chromosomes say about the origin and evolution of insects and other arthropods].

    PubMed

    Lukhtanov, V A; Kuznetsova, V G

    2010-09-01

    At the turn of the 21st century, the use of molecular and molecular cytogenetic methods led to revolutionary advances in systematics of insects and other arthropods. Analysis of nuclear and mitochondrial genes, as well as investigation of structural rearrangements in the mitochondrial chromosome convincingly supported the Pancrustacea hypothesis, according to which insects originated directly from crustaceans, whereas myriapods are not closely related to them. The presence of the specific telomeric motif TTAGG confirmed the monophyletic origin of arthropods (Arthropoda) and the assignment of tongue worms (Pentastomida) to this type. Several different types of telomeric sequences have been found within the class of insects. Investigation of the molecular organization of these sequences may shed light on the relationships between the orders Diptera, Siphonaptera, and Mecoptera and on the origin of such enigmatic groups as the orders Strepsiptera, Zoraptera and suborder Coleorrhyncha. PMID:21061630

  7. Ecological structuring of bacterial and archaeal taxa in surface ocean waters.

    PubMed

    Yilmaz, Pelin; Iversen, Morten H; Hankeln, Wolfgang; Kottmann, Renzo; Quast, Christian; Glöckner, Frank O

    2012-08-01

    The Global Ocean Sampling (GOS) expedition is currently the largest and geographically most comprehensive metagenomic dataset, including samples from the Atlantic, Pacific, and Indian Oceans. This study makes use of the wide range of environmental conditions and habitats encompassed within the GOS sites in order to investigate the ecological structuring of bacterial and archaeal taxon ranks. Community structures based on taxonomically classified 16S ribosomal RNA (rRNA) gene fragments at phylum, class, order, family, and genus rank levels were examined using multivariate statistical analysis, and the results were inspected in the context of oceanographic environmental variables and structured habitat classifications. At all taxon rank levels, community structures of neritic, oceanic, estuarine biomes, as well as other exotic biomes (salt marsh, lake, mangrove), were readily distinguishable from each other. A strong structuring of the communities with chlorophyll a concentration and a weaker yet significant structuring with temperature and salinity were observed. Furthermore, there were significant correlations between community structures and habitat classification. These results were used for further investigation of one-to-one relationships between taxa and environment and provided indications for ecological preferences shaped by primary production for both cultured and uncultured bacterial and archaeal clades. PMID:22416918

  8. Campylobacter concisus utilizes blood but not short chain fatty acids despite showing associations with Firmicutes taxa.

    PubMed

    Kaakoush, Nadeem O; Thomas, Donald S; Ruzayqat, Mahmoud M; Lynch, David; Leach, Steven T; Lemberg, Daniel A; Day, Andrew S; Mitchell, Hazel M

    2016-08-01

    Campylobacter concisus is a member of the oral microbiota that has been associated with the development of inflammatory bowel diseases. However, the role of the bacterium in disease aetiology remains poorly understood. Here, we examine optimal conditions for the growth of C. concisus, and the pathogenic potential of this bacterium in human gastrointestinal cells from the upper tract. Further, the presence of C. concisus in the lower tract of Crohn's disease (CD) patients undergoing therapy is observed, and the associations of C. concisus with the abundance of other microbial taxa and compounds they produce are evaluated. C. concisus strains had the ability to tolerate moderate levels of acidity, adhere to and invade esophageal and gastric cells; however, these properties did not correlate with their pathogenic potential in intestinal cells. The presence of the bacterium in the lower gut of CD patients was associated with an increased relative abundance of Faecalibacterium and Lachnospiraceae incertae sedis. Short chain fatty acids that can be produced by these microbial species did not appear to be responsible for this association. However, we identified genetic similarity between C. concisus and Firmicutes, specifically within aspartate and glutamate racemases. The potential pathogenesis of C. concisus in the upper gastrointestinal tract, and the responsiveness of the bacterium to therapy in a subset of CD patients warrant further investigation into whether this bacterium has a causal role in disease or its presence is incidental. PMID:27339421

  9. Firmicutes dominate the bacterial taxa within sugar-cane processing plants

    PubMed Central

    Sharmin, Farhana; Wakelin, Steve; Huygens, Flavia; Hargreaves, Megan

    2013-01-01

    Sugar cane processing sites are characterised by high sugar/hemicellulose levels, available moisture and warm conditions, and are relatively unexplored unique microbial environments. The PhyloChip microarray was used to investigate bacterial diversity and community composition in three Australian sugar cane processing plants. These ecosystems were highly complex and dominated by four main Phyla, Firmicutes (the most dominant), followed by Proteobacteria, Bacteroidetes, and Chloroflexi. Significant variation (p < 0.05) in community structure occurred between samples collected from ‘floor dump sediment’, ‘cooling tower water’, and ‘bagasse leachate’. Many bacterial Classes contributed to these differences, however most were of low numerical abundance. Separation in community composition was also linked to Classes of Firmicutes, particularly Bacillales, Lactobacillales and Clostridiales, whose dominance is likely to be linked to their physiology as ‘lactic acid bacteria’, capable of fermenting the sugars present. This process may help displace other bacterial taxa, providing a competitive advantage for Firmicutes bacteria. PMID:24177592

  10. Multiple taxa in the Phoma-complex associate with black elder (Sambucus nigra L.).

    PubMed

    Walter, Hildrun; Muggia, Lucia; Fritscher, Michael; Holler, Alessandro; Horvat, Deborah; Guttenberger, Helmut; Simon, Uwe K

    2016-01-01

    The fungus Boeremia sambuci-nigrae (formerly Phoma sambuci-nigrae) causes the corymb wilt disease in elder (Sambucus nigra L.). Here, we assessed the genetic diversity of fungi within the Phoma-complex which associate with commercially cultivated elder in Styria (Austria). We sampled leaves, corymb stalks and berries of elder trees in one organically and in four conventionally managed orchards. In each orchard an area was left untreated allowing a sampling of fungicide treated and untreated trees. Nineteen taxa in the Phoma-complex were isolated and identified based on ITS and LSU nucDNA sequences. One isolate is closely related to Chaetosphaeronema, whereas the majority of the strains belong to the genera Epicoccum and Boeremia in Didymellaceae. Six isolates are monophyletic with Boeremia sambuci-nigrae. The results indicate a varying effectiveness of fungicide treatment for the different fungal groups investigated. The diverse distribution of isolates among the sampling sites suggests the influence of treatment effects and possibly also of climatic conditions. PMID:26693683

  11. Avirulence effector discovery in a plant galling and plant parasitic arthropod, the Hessian fly (Mayetiola destructor).

    PubMed

    Aggarwal, Rajat; Subramanyam, Subhashree; Zhao, Chaoyang; Chen, Ming-Shun; Harris, Marion O; Stuart, Jeff J

    2014-01-01

    Highly specialized obligate plant-parasites exist within several groups of arthropods (insects and mites). Many of these are important pests, but the molecular basis of their parasitism and its evolution are poorly understood. One hypothesis is that plant parasitic arthropods use effector proteins to defeat basal plant immunity and modulate plant growth. Because avirulence (Avr) gene discovery is a reliable method of effector identification, we tested this hypothesis using high-resolution molecular genetic mapping of an Avr gene (vH13) in the Hessian fly (HF, Mayetiola destructor), an important gall midge pest of wheat (Triticum spp.). Chromosome walking resolved the position of vH13, and revealed alleles that determine whether HF larvae are virulent (survive) or avirulent (die) on wheat seedlings carrying the wheat H13 resistance gene. Association mapping found three independent insertions in vH13 that appear to be responsible for H13-virulence in field populations. We observed vH13 transcription in H13-avirulent larvae and the salivary glands of H13-avirulent larvae, but not in H13-virulent larvae. RNA-interference-knockdown of vH13 transcripts allowed some H13-avirulent larvae to escape H13-directed resistance. vH13 is the first Avr gene identified in an arthropod. It encodes a small modular protein with no sequence similarities to other proteins in GenBank. These data clearly support the hypothesis that an effector-based strategy has evolved in multiple lineages of plant parasites, including arthropods. PMID:24964065

  12. The Interactive Effects of Pulsed Grazing Disturbance and Patch Size Vary among Wetland Arthropod Guilds

    PubMed Central

    Armitage, Anna R.; Ho, Chuan-Kai; Quigg, Antonietta

    2013-01-01

    Pulse disturbances and habitat patch size can determine community composition independently or in concert, and may be particularly influential on small spatial scales for organisms with low mobility. In a field experiment, we investigated whether the effects of a pulsed disturbance that simulated a grazing event varied with habitat patch size. We focused on the short-term responses of multiple co-occurring emergent salt marsh arthropods with differing levels of mobility and dispersal potential. As part of a marsh restoration project, two types of emergent marsh structures were created: small circular mounds (0.5 m diameter) separated by several meters of aquatic habitat, and larger, elongated terraces (>50 m long). Study plots (0.25 m2) were established on both structures; in a subset of plots, we simulated a pulsed grazing disturbance event by clipping the aboveground tissue of emergent plants, primarily Spartina alterniflora. At the end of the two-month recovery period, Ischnodemus (Hemiptera: Blissidae) density was over 50% lower in disturbed treatments within both large (terrace) and small (mound) patches. Predatory spider treatment responses were similar to Ischnodemus responses, suggesting a trophic relationship between those two arthropod groups. Alternatively, spiders may have been directly affected by the loss of shelter in the disturbed plots. Prokelisia (Homoptera: Delphacidae), which are generally more mobile than Ischnodemus, were not affected by disturbance treatment or by patch size, suggesting the potential for rapid recolonization following disturbance. Larval stem borers decreased by an order of magnitude in disturbed plots, but only in the large patches. In general, the disturbance effects of vegetation removal on arthropod density and community composition were stronger than patch size effects, and there were few interactions between pulsed disturbance and patch size. Rather, emergent marsh arthropod responses to disturbance and habitat area

  13. Avirulence Effector Discovery in a Plant Galling and Plant Parasitic Arthropod, the Hessian Fly (Mayetiola destructor)

    PubMed Central

    Aggarwal, Rajat; Subramanyam, Subhashree; Zhao, Chaoyang; Chen, Ming-Shun; Harris, Marion O.; Stuart, Jeff J.

    2014-01-01

    Highly specialized obligate plant-parasites exist within several groups of arthropods (insects and mites). Many of these are important pests, but the molecular basis of their parasitism and its evolution are poorly understood. One hypothesis is that plant parasitic arthropods use effector proteins to defeat basal plant immunity and modulate plant growth. Because avirulence (Avr) gene discovery is a reliable method of effector identification, we tested this hypothesis using high-resolution molecular genetic mapping of an Avr gene (vH13) in the Hessian fly (HF, Mayetiola destructor), an important gall midge pest of wheat (Triticum spp.). Chromosome walking resolved the position of vH13, and revealed alleles that determine whether HF larvae are virulent (survive) or avirulent (die) on wheat seedlings carrying the wheat H13 resistance gene. Association mapping found three independent insertions in vH13 that appear to be responsible for H13-virulence in field populations. We observed vH13 transcription in H13-avirulent larvae and the salivary glands of H13-avirulent larvae, but not in H13-virulent larvae. RNA-interference-knockdown of vH13 transcripts allowed some H13-avirulent larvae to escape H13-directed resistance. vH13 is the first Avr gene identified in an arthropod. It encodes a small modular protein with no sequence similarities to other proteins in GenBank. These data clearly support the hypothesis that an effector-based strategy has evolved in multiple lineages of plant parasites, including arthropods. PMID:24964065

  14. The Effects of Timing of Grazing on Plant and Arthropod Communities in High-Elevation Grasslands

    PubMed Central

    Davis, Stacy C.; Burkle, Laura A.; Cross, Wyatt F.; Cutting, Kyle A.

    2014-01-01

    Livestock grazing can be used as a key management tool for maintaining healthy ecosystems. However, the effectiveness of using grazing to modify habitat for species of conservation concern depends on how the grazing regime is implemented. Timing of grazing is one grazing regime component that is less understood than grazing intensity and grazer identity, but is predicted to have important implications for plant and higher trophic level responses. We experimentally assessed how timing of cattle grazing affected plant and arthropod communities in high-elevation grasslands of southwest Montana to better evaluate its use as a tool for multi-trophic level management. We manipulated timing of grazing, with one grazing treatment beginning in mid-June and the other in mid-July, in two experiments conducted in different grassland habitat types (i.e., wet meadow and upland) in 2011 and 2012. In the upland grassland experiment, we found that both early and late grazing treatments reduced forb biomass, whereas graminoid biomass was only reduced with late grazing. Grazing earlier in the growing season versus later did not result in greater recovery of graminoid or forb biomass as expected. In addition, the density of the most ubiquitous grassland arthropod order (Hemiptera) was reduced by both grazing treatments in upland grasslands. A comparison of end-of-season plant responses to grazing in upland versus wet meadow grasslands revealed that grazing reduced graminoid biomass in the wet meadow and forb biomass in the upland, irrespective of timing of grazing. Both grazing treatments also reduced end-of-season total arthropod and Hemiptera densities and Hemiptera biomass in both grassland habitat types. Our results indicate that both early and late season herbivory affect many plant and arthropod characteristics in a similar manner, but grazing earlier may negatively impact species of conservation concern requiring forage earlier in the growing season. PMID:25338008

  15. Deep-time patterns of tissue consumption by terrestrial arthropod herbivores.

    PubMed

    Labandeira, Conrad C

    2013-04-01

    A survey of the fossil record of land-plant tissues and their damage by arthropods reveals several results that shed light on trophic trends in host-plant resource use by arthropods. All 14 major plant tissues were present by the end of the Devonian, representing the earliest 20% of the terrestrial biota. During this interval, two types of time lags separate the point between when tissues first originated from their earliest consumption by herbivorous arthropods. For epidermis, parenchyma, collenchyma and xylem, live tissue consumption was rapid, occurring on average 10 m.y. after the earliest tissue records. By contrast, structural tissues (periderm, sclerenchyma), tissues with actively dividing cells (apical, lateral, intercalary meristems), and reproductive tissues (spores, megagametophytes, integuments) experienced approximately a 9-fold (92 m.y.) delay in arthropod herbivory, extending well into the Carboniferous Period. Phloem similarly presents a delay of 85 m.y., but this incongruously long lag-time may be attributed to the lack of preservation of this tissue in early vascular plants. Nevertheless, the presence of phloem can be indicated from planar spaces adjacent well-preserved xylem, or inferred from a known anatomy of the same plant taxon in better preserved material, especially permineralisations. The trophic partitioning of epidermis, parenchyma, phloem and xylem increases considerably to the present, probably a consequence of dietary specialization or consumption of whole leaves by several herbivore functional feeding groups. Structural tissues, meristematic tissues and reproductive tissues minimally have been consumed throughout the fossil record, consistent with their long lags to herbivory during the earlier Paleozoic. Neither angiosperm dominance in floras nor global environmental perturbations had any discernible effect on herbivore trophic partitioning of plant tissues. PMID:23525577

  16. The value of urban vacant land to support arthropod biodiversity and ecosystem services.

    PubMed

    Gardiner, Mary M; Burkman, Caitlin E; Prajzner, Scott P

    2013-12-01

    The expansion of urban areas is occurring globally, but not all city neighborhoods are gaining population. Because of economic decline and the recent foreclosure crisis, many U.S. cities are demolishing abandoned residential structures to create parcels of vacant land. In some cities, weak housing markets have, or will likely, recover in the near term, and these parcels will be redeveloped. However, in other cities, large numbers of abandoned parcels have no significant market value and no likelihood of near-term redevelopment. The creation of these vacated green spaces could offer opportunities to preserve declining species, restore ecosystem functions, and support diverse ecosystem services. Arthropods are an important indicator of the ability of urban vacant land to serve multiple functions, from conservation to food production. Across Europe, vacant lands have been found to support a diversity of rare species, and similar examinations of arthropods within this habitat are underway in the United States. In addition, using vacant land as a resource for local food production is growing rapidly worldwide. Arthropods play key roles in the sustainability of food production in cities, and land conversion to farming has been found to influence their community composition and function. A greater focus on quantifying the current ecological value of vacant land and further assessment of how changes in its ecosystem management affect biodiversity and ecosystem processes is clearly needed. Herein, we specifically focus on the role of arthropods in addressing these priorities to advance our ecological understanding of the functional role of vacant land habitats in cities. PMID:24468552

  17. Deep-time patterns of tissue consumption by terrestrial arthropod herbivores

    NASA Astrophysics Data System (ADS)

    Labandeira, Conrad C.

    2013-04-01

    A survey of the fossil record of land-plant tissues and their damage by arthropods reveals several results that shed light on trophic trends in host-plant resource use by arthropods. All 14 major plant tissues were present by the end of the Devonian, representing the earliest 20 % of the terrestrial biota. During this interval, two types of time lags separate the point between when tissues first originated from their earliest consumption by herbivorous arthropods. For epidermis, parenchyma, collenchyma and xylem, live tissue consumption was rapid, occurring on average 10 m.y. after the earliest tissue records. By contrast, structural tissues (periderm, sclerenchyma), tissues with actively dividing cells (apical, lateral, intercalary meristems), and reproductive tissues (spores, megagametophytes, integuments) experienced approximately a 9-fold (92 m.y.) delay in arthropod herbivory, extending well into the Carboniferous Period. Phloem similarly presents a delay of 85 m.y., but this incongruously long lag-time may be attributed to the lack of preservation of this tissue in early vascular plants. Nevertheless, the presence of phloem can be indicated from planar spaces adjacent well-preserved xylem, or inferred from a known anatomy of the same plant taxon in better preserved material, especially permineralisations. The trophic partitioning of epidermis, parenchyma, phloem and xylem increases considerably to the present, probably a consequence of dietary specialization or consumption of whole leaves by several herbivore functional feeding groups. Structural tissues, meristematic tissues and reproductive tissues minimally have been consumed throughout the fossil record, consistent with their long lags to herbivory during the earlier Paleozoic. Neither angiosperm dominance in floras nor global environmental perturbations had any discernible effect on herbivore trophic partitioning of plant tissues.

  18. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    PubMed

    Lemessa, Debissa; Hambäck, Peter A; Hylander, Kristoffer

    2015-01-01

    Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests. PMID:25961306

  19. Arthropods of Rose Atoll with special reference to ants and Pulvinaria Urbicola Scales (Hempitera Coccidae) on Pisonia Grandis trees

    USGS Publications Warehouse

    Banko, Paul C.; Peck, Robert W.; Pendleton, Frank; Schmaedick, Mark; Ernsberger, Kelsie

    2014-01-01

    Rose Atoll, at the eastern end of the Samoan Archipelago, is a small but important refuge for seabirds, shorebirds, and sea turtles. While the vertebrate community is relatively well-studied, the terrestrial arthropod fauna, and its role in ecosystem function, are poorly known. Arthropods may be influencing the decline of Pisonia grandis, an ecologically important tree that once dominated the 6.6 ha of land on Rose Atoll. Reasons for the decline are not fully understood but a facultative relationship between two invasive arthropods, the soft scale Pulvinaria urbicola and ants, likely has contributed to tree death. The primary objectives of this study were to systematically survey the terrestrial arthropod fauna and identify ant species that tend scales on Pisonia. Using an array of standard arthropod collecting techniques, at least 73 species from 20 orders were identified, including nine ant species. Of the ants collected, only Tetramorium bicarinatum and T. simillimum were observed tending scales on Pisonia. No known natural enemies of Pulvinaria scales were found, suggesting little predation on scale populations. Treatment of Pisonia with the systemic insecticide imidacloprid failed to eliminate Pulvinaria scales, although short-term suppression apparently occurred. The arthropod fauna of Rose Atoll is dominated by exotic species that likely have a significant impact on the structure and function of the island’s ecosystem.

  20. Arthropod but Not Bird Predation in Ethiopian Homegardens Is Higher in Tree-Poor than in Tree-Rich Landscapes

    PubMed Central

    Lemessa, Debissa; Hambäck, Peter A.; Hylander, Kristoffer

    2015-01-01

    Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7–9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests. PMID:25961306

  1. Spatial heterogeneity in the relative impacts of foliar quality and predation pressure on red oak, Quercus rubra, arthropod communities.

    PubMed

    Zehnder, Caralyn B; Stodola, Kirk W; Cooper, Robert J; Hunter, Mark D

    2010-12-01

    Predation pressure and resource availability often interact in structuring herbivore communities, with their relative influence varying in space and time. The operation of multiple ecological pressures and guild-specific herbivore responses may combine to override simple predictions of how the roles of plant quality and predation pressure vary in space. For 2 years at the Coweeta LTER in the Southern Appalachian Mountains, we conducted a bird exclosure experiment on red oak (Quercus rubra) saplings to investigate the effects of bird predation on red oak arthropod communities. We established bird exclosures at six sites along an elevational gradient and estimated variation in foliar nitrogen and bird predation pressure along this gradient. Foliar nitrogen concentrations increased with elevation while our index of bird predation pressure was variable across sites. Greater arthropod densities were detected inside exclosures; however, this result was mainly driven by the response of phloem feeders which were much more prevalent inside exclosures than on control trees. There was little evidence for an effect of bird predation on the other arthropod guilds. Consequently, there was no evidence of a trophic cascade either in terms of leaf damage or tree growth. Finally, we found more variation in arthropod density among trees within sites than variation in arthropod density among sites, indicating the importance of micro-site variation in structuring arthropod communities. PMID:20711610

  2. A nomenclator of extant and fossil taxa of the Valvatidae (Gastropoda, Ectobranchia)

    PubMed Central

    Haszprunar, Gerhard

    2014-01-01

    Abstract A compilation of all supra- and (infra-) specific taxa of extant and fossil Valvatidae, a group of freshwater operculate snails, is provided, including taxa initially described in this family and subsequently classified in other families, as well as names containing errors or misspellings. The extensive reference list is directly linked to the available electronic source (digital view or pdf-download) of the respective papers. PMID:24578604

  3. [Community structure and its dynamics of predatory arthropod in jujube orchards intercropped with different herbage species].

    PubMed

    Shi, Guanglu; Wang, Younian; Miao, Zhenwang; Li, Dengke; Zhang, Tieqiang; Yu, Tongquan; Ji, Qianlong; Dong, Hui

    2006-11-01

    By using community structural characteristic indices and principal component analysis, this paper studied the community structure and its dynamics of predatory arthropod in the jujube orchards intercropped with Astrugalus complanatus, Trifolium repen, Lotus comiculotus, and Medicago sativa. The results showed that in all test jujube orchards, spider and predatory insects were the predominant components of the predatory arthropod community, and their relative abundances were 48.3% - 52.7% and 38.8% - 44.4% , respectively. There were significant differences (P < 0.05) in the mean density, diversity, and evenness of the most common predatory arthropod groups in the jujube orchards intercropped with different herbage species, with the sequence of intercropped with Lotus comiculotus > Medicago sativa > Astrugalus complanatu > Trifolium repens, but for dominant concentration index, the sequence was intercropped with Trifolium repens > Astrugalus complanatu > Medicago sativa > Lotus comiculotus. The average density of predatory spiders was significant higher (P < 0.05) than that of predatory insects in all test jujube orchards. The individuals of Coccinellidae, Pentatomidae, inoccllidae, Chrysopidae, Thomisidae, Araneidae and Phytoseiidae played the dominant role in the community. PMID:17269332

  4. Structural Diversity of Arthropod Biophotonic Nanostructures Spans Amphiphilic Phase-Space

    SciTech Connect

    Saranathan, Vinod Kumar; Seago, Ainsley E.; Sandy, Alec; Narayanan, Suresh; Mochrie, Simon G.J.; Dufresne, Eric R.; Cao, Hui; Osuji, Chinedum O.; Prum, Richard Owen

    2015-05-04

    Many organisms, especially arthropods, produce vivid interference colors using diverse mesoscopic (100-350 nm) integumentary biophotonic nanostructures that are increasingly being investigated for technological applications. Despite a century of interest, precise structural knowledge of many biophotonic nanostructures and the mechanisms controlling their development remain tentative, when such knowledge can open novel biomimetic routes to facilely self-assemble tunable, multifunctional materials. Here, we use synchrotron small-angle X-ray scattering and electron microscopy to characterize the photonic nanostructure of 140 integumentary scales and setae from ~127 species of terrestrial arthropods in 85 genera from 5 orders. We report a rich nanostructural diversity, including triply periodic bicontinuous networks, close-packed spheres, inverse columnar, perforated lamellar, and disordered spongelike morphologies, commonly observed as stable phases of amphiphilic surfactants, block copolymer, and lyotropic lipid-water systems. Diverse arthropod lineages appear to have independently evolved to utilize the self-assembly of infolding lipid-bilayer membranes to develop biophotonic nanostructures that span the phase-space of amphiphilic morphologies, but at optical length scales.

  5. Arthropod visual predators in the early pelagic ecosystem: evidence from the Burgess Shale and Chengjiang biotas.

    PubMed

    Vannier, J; García-Bellido, D C; Hu, S-X; Chen, A-L

    2009-07-22

    Exceptional fossil specimens with preserved soft parts from the Maotianshan Shale (ca 520 Myr ago) and the Burgess Shale (505 Myr ago) biotas indicate that the worldwide distributed bivalved arthropod Isoxys was probably a non-benthic visual predator. New lines of evidence come from the functional morphology of its powerful prehensile frontal appendages that, combined with large spherical eyes, are thought to have played a key role in the recognition and capture of swimming or epibenthic prey. The swimming and steering of this arthropod was achieved by the beating of multiple setose exopods and a flap-like telson. The appendage morphology of Isoxys indicates possible phylogenetical relationships with the megacheirans, a widespread group of assumed predator arthropods characterized by a pre-oral 'great appendage'. Evidence from functional morphology and taphonomy suggests that Isoxys was able to migrate through the water column and was possibly exploiting hyperbenthic niches for food. Although certainly not unique, the case of Isoxys supports the idea that off-bottom animal interactions such as predation, associated with complex feeding strategies and behaviours (e.g. vertical migration and hunting) were established by the Early Cambrian. It also suggests that a prototype of a pelagic food chain had already started to build-up at least in the lower levels of the water column. PMID:19403536

  6. Arthropod visual predators in the early pelagic ecosystem: evidence from the Burgess Shale and Chengjiang biotas

    PubMed Central

    Vannier, J.; García-Bellido, D.C.; Hu, S.-X.; Chen, A.-L.

    2009-01-01

    Exceptional fossil specimens with preserved soft parts from the Maotianshan Shale (ca 520 Myr ago) and the Burgess Shale (505 Myr ago) biotas indicate that the worldwide distributed bivalved arthropod Isoxys was probably a non-benthic visual predator. New lines of evidence come from the functional morphology of its powerful prehensile frontal appendages that, combined with large spherical eyes, are thought to have played a key role in the recognition and capture of swimming or epibenthic prey. The swimming and steering of this arthropod was achieved by the beating of multiple setose exopods and a flap-like telson. The appendage morphology of Isoxys indicates possible phylogenetical relationships with the megacheirans, a widespread group of assumed predator arthropods characterized by a pre-oral ‘great appendage’. Evidence from functional morphology and taphonomy suggests that Isoxys was able to migrate through the water column and was possibly exploiting hyperbenthic niches for food. Although certainly not unique, the case of Isoxys supports the idea that off-bottom animal interactions such as predation, associated with complex feeding strategies and behaviours (e.g. vertical migration and hunting) were established by the Early Cambrian. It also suggests that a prototype of a pelagic food chain had already started to build-up at least in the lower levels of the water column. PMID:19403536

  7. Arthropod phylogeny: onychophoran brain organization suggests an archaic relationship with a chelicerate stem lineage.

    PubMed

    Strausfeld, Nicholas J; Strausfeld, Camilla Mok; Loesel, Rudi; Rowell, David; Stowe, Sally

    2006-08-01

    Neuroanatomical studies have demonstrated that the architecture and organization among neuropils are highly conserved within any order of arthropods. The shapes of nerve cells and their neuropilar arrangements provide robust characters for phylogenetic analyses. Such analyses so far have agreed with molecular phylogenies in demonstrating that entomostracans+malacostracans belong to a clade (Tetraconata) that includes the hexapods. However, relationships among what are considered to be paraphyletic groups or among the stem arthropods have not yet been satisfactorily resolved. The present parsimony analyses of independent neuroarchitectural characters from 27 arthropods and lobopods demonstrate relationships that are congruent with phylogenies derived from molecular studies, except for the status of the Onychophora. The present account describes the brain of the onychophoran Euperipatoides rowelli, demonstrating that the structure and arrangements of its neurons, cerebral neuropils and sensory centres are distinct from arrangements in the brains of mandibulates. Neuroanatomical evidence suggests that the organization of the onychophoran brain is similar to that of the brains of chelicerates. PMID:16822744

  8. Red imported fire ant impacts on upland arthropods in Southern Mississippi

    USGS Publications Warehouse

    Epperson, D.M.; Allen, C.R.

    2010-01-01

    Red imported fire ants (Solenopsis invicta) have negative impacts on a broad array of invertebrate species. We investigated the impacts of fire ants on the upland arthropod community on 20???40 ha study sites in southern Mississippi. Study sites were sampled from 19972000 before, during, and after fire ant bait treatments to reduce fire ant populations. Fire ant abundance was assessed with bait transects on all sites, and fire ant population indices were estimated on a subset of study sites. Species richness and diversity of other ant species was also assessed from bait transects. Insect biomass and diversity was determined from light trap samples. Following treatments, fire ant abundance and population indices were significantly reduced, and ant species diversity and richness were greater on treated sites. Arthropod biomass, species diversity and species richness estimated from light trap samples were negatively correlated with fire ant abundance, but there were no observable treatment effects. Solenopsis invicta has the potential to negatively impact native arthropod communities resulting in a potential loss of both species and function.

  9. Efficient sampling of ground-dwelling arthropods using pitfall traps in arid steppes.

    PubMed

    Cheli, Germán H; Corley, Juan C

    2010-01-01

    Pitfall trapping is probably the most frequently used method for sampling ground-dwelling arthropods. While the capture of specimens in pitfall traps largely depends on the number of individuals in the sampled area, trap design and trapping effort for a given environment, can also affect sampling success. The aim of this study was to determine the best pitfall trapping design for collecting ground-dwelling arthropods in the wind-blown and cold arid steppe areas of Patagonia. We tested four designs of traps, six types of preservative and different times of activation as well as the quantity of traps. Both preservation attributes and sampling efficiency differed between different trap designs and fluids compared. We conclude that in order to obtain reliable data on the structure of a community of ground-dwelling arthropods in Patagonia, at least three pitfall traps per experimental unit are required. In addition, traps should be opened for a minimum of 10 days filled with 300 ml of 30% ethylene glycol. We also suggested the use of a simple trap design (i. e. without funnel or roof). We believe these findings will contribute to more appropriate sampling of the ground dwelling fauna of Patagonia as well as other arid areas, leading to more reliable diversity studies. PMID:21271057

  10. Transinfection: a method to investigate Wolbachia-host interactions and control arthropod-borne disease

    PubMed Central

    Hughes, Grant L.; Rasgon, Jason L.

    2014-01-01

    The bacterial endosymbiont Wolbachia manipulates arthropod host biology in numerous ways including sex ratio distortion and differential offspring survival. These bacteria infect a vast array of arthropods, some of which pose serious agricultural and human health threats. Wolbachia-mediated phenotypes such as cytoplasmic incompatibility and/or pathogen interference can be utilized for vector and disease control. However, many medically important vectors and important agricultural species are uninfected or are infected with strains of Wolbachia that do not elicit phenotypes desirable for disease or pest control. The ability to transfer strains of Wolbachia into new hosts (transinfection) can create novel Wolbachia-host associations. Transinfection has two primary benefits. First, Wolbachia-host interactions can be examined to tease apart the influence of the host and bacteria on phenotypes. Secondly, desirable phenotypes induced by Wolbachia in a particular insect can be transferred to another recipient host. This can allow for manipulation of insect populations that transmit pathogens or detrimentally affect agriculture. As such, transinfection is a valuable tool to explore Wolbachia biology and control arthropod-borne disease. This review summarizes what is currently known about Wolbachia transinfection methods and applications. We also provide a comprehensive list of published successful and unsuccessful Wolbachia transinfection attempts. PMID:24329998

  11. Pesticide-Induced Stress in Arthropod Pests for Optimized Integrated Pest Management Programs.

    PubMed

    Guedes, R N C; Smagghe, G; Stark, J D; Desneux, N

    2016-03-11

    More than six decades after the onset of wide-scale commercial use of synthetic pesticides and more than fifty years after Rachel Carson's Silent Spring, pesticides, particularly insecticides, arguably remain the most influential pest management tool around the globe. Nevertheless, pesticide use is still a controversial issue and is at the regulatory forefront in most countries. The older generation of insecticide groups has been largely replaced by a plethora of novel molecules that exhibit improved human and environmental safety profiles. However, the use of such compounds is guided by their short-term efficacy; the indirect and subtler effects on their target species, namely arthropod pest species, have been neglected. Curiously, comprehensive risk assessments have increasingly explored effects on nontarget species, contrasting with the majority of efforts focused on the target arthropod pest species. The present review mitigates this shortcoming by hierarchically exploring within an ecotoxicology framework applied to integrated pest management the myriad effects of insecticide use on arthropod pest species. PMID:26473315

  12. The diversity of reproductive parasites among arthropods: Wolbachia do not walk alone

    PubMed Central

    Duron, Olivier; Bouchon, Didier; Boutin, Sébastien; Bellamy, Lawrence; Zhou, Liqin; Engelstädter, Jan; Hurst, Gregory D

    2008-01-01

    Background Inherited bacteria have come to be recognised as important components of arthropod biology. In addition to mutualistic symbioses, a range of other inherited bacteria are known to act either as reproductive parasites or as secondary symbionts. Whilst the incidence of the α-proteobacterium Wolbachia is relatively well established, the current knowledge of other inherited bacteria is much weaker. Here, we tested 136 arthropod species for a range of inherited bacteria known to demonstrate reproductive parasitism, sampling each species more intensively than in past surveys. Results The inclusion of inherited bacteria other than Wolbachia increased the number of infections recorded in our sample from 33 to 57, and the proportion of species infected from 22.8% to 32.4%. Thus, whilst Wolbachia remained the dominant inherited bacterium, it alone was responsible for around half of all inherited infections of the bacteria sampled, with members of the Cardinium, Arsenophonus and Spiroplasma ixodetis clades each occurring in 4% to 7% of all species. The observation that infection was sometimes rare within host populations, and that there was variation in presence of symbionts between populations indicates that our survey will itself underscore incidence. Conclusion This extensive survey demonstrates that at least a third of arthropod species are infected by a diverse assemblage of maternally inherited bacteria that are likely to strongly influence their hosts' biology, and indicates an urgent need to establish the nature of the interaction between non-Wolbachia bacteria and their hosts. PMID:18577218

  13. Fungal metabolic plasticity and sexual development mediate induced resistance to arthropod fungivory.

    PubMed

    Döll, Katharina; Chatterjee, Subhankar; Scheu, Stefan; Karlovsky, Petr; Rohlfs, Marko

    2013-11-22

    Prey organisms do not tolerate predator attack passively but react with a multitude of inducible defensive strategies. Although inducible defence strategies are well known in plants attacked by herbivorous insects, induced resistance of fungi against fungivorous animals is largely unknown. Resistance to fungivory is thought to be mediated by chemical properties of fungal tissue, i.e. by production of toxic secondary metabolites. However, whether fungi change their secondary metabolite composition to increase resistance against arthropod fungivory is unknown. We demonstrate that grazing by a soil arthropod, Folsomia candida, on the filamentous fungus Aspergillus nidulans induces a phenotype that repels future fungivores and retards fungivore growth. Arthropod-exposed colonies produced significantly higher amounts of toxic secondary metabolites and invested more in sexual reproduction relative to unchallenged fungi. Compared with vegetative tissue and asexual conidiospores, sexual fruiting bodies turned out to be highly resistant against fungivory in facultative sexual A. nidulans. This indicates that fungivore grazing triggers co-regulated allocation of resources to sexual reproduction and chemical defence in A. nidulans. Plastic investment in facultative sex and chemical defence may have evolved as a fungal strategy to escape from predation. PMID:24068353

  14. Structure and development of onychophoran eyes: what is the ancestral visual organ in arthropods?

    PubMed

    Mayer, Georg

    2006-12-01

    Scarce and controversial information on visual organs and their innervation in Onychophora currently do not allow a thorough comparison with Euarthropoda. Therefore, this study sets out to provide additional data on the architecture and morphogenesis of the onychophoran visual system and to explore similarities and differences between the visual organs of onychophorans and other arthropods. Based on the new data for Epiperipatus biolleyi (Peripatidae) and Metaperipatus blainvillei (Peripatopsidae), it is suggested that the compound eyes represent an autapomorphy of Euarthropoda since similarities with the onychophoran eyes are weak or absent. Instead, the innervation from a central rather than lateral part of the brain, the presence of only one (paired or unpaired) visual center, and a similar ontogenetic origin from an ectodermal groove rather than a proliferation zone suggest homology between the onychophoran eyes and the median ocelli of euarthropods. In conclusion, I suggest that the last common ancestor of arthropods bore only one pair of ocellus-like visual organs that were modified in several arthropod lineages. This hypothesis is supported by recent paleontological data. PMID:18089073

  15. Importance of terrestrial arthropods as subsidies in lowland Neotropical rain forest stream ecosystems

    USGS Publications Warehouse

    Small, Gaston E.; Torres, Pedro J.; Schwizer, Lauren M.; Duff, John H.; Pringle, Catherine M.

    2013-01-01

    The importance of terrestrial arthropods has been documented in temperate stream ecosystems, but little is known about the magnitude of these inputs in tropical streams. Terrestrial arthropods falling from the canopy of tropical forests may be an important subsidy to tropical stream food webs and could also represent an important flux of nitrogen (N) and phosphorus (P) in nutrient-poor headwater streams. We quantified input rates of terrestrial insects in eight streams draining lowland tropical wet forest in Costa Rica. In two focal headwater streams, we also measured capture efficiency by the fish assemblage and quantified terrestrially derived N- and P-excretion relative to stream nutrient uptake rates. Average input rates of terrestrial insects ranged from 5 to 41 mg dry mass/m2/d, exceeding previous measurements of aquatic invertebrate secondary production in these study streams, and were relatively consistent year-round, in contrast to values reported in temperate streams. Terrestrial insects accounted for half of the diet of the dominant fish species, Priapicthys annectens. Although terrestrially derived fish excretion was found to be a small flux relative to measured nutrient uptake rates in the focal streams, the efficient capture and processing of terrestrial arthropods by fish made these nutrients available to the local stream ecosystem. This aquatic-terrestrial linkage is likely being decoupled by deforestation in many tropical regions, with largely unknown but potentially important ecological consequences.

  16. A novel approach to the measurement of surfactant parameters in arthropod digestive juices.

    PubMed

    Romih, Tea; Kogej, Ksenija; Drobne, Damjana

    2016-05-01

    In arthropods, the determination of two important parameters of digestive juices, i.e. the total surfactant concentration and the critical micelle concentration (CMC), is challenging due to small sample volumes and low surfactant concentrations. In this work, we report a successful implementation of potentiometric titrations using the surfactant ion-selective electrode (SISE) and the pyrene fluorescence method (PFM) for the determination of the total surfactant concentration and CMC in the digestive juice of terrestrial isopod crustaceans Porcellio scaber. Pooled digestive juice extracts of four (SISE) or two (PFM) animals were used per measurement run. In both cases, digestive juice extracts in 100μL of deionized water were sufficient for one measurement run. The total surfactant concentration of P. scaber digestive juice was determined to be 9.2±3.5mM and the CMC was approximately 90μM. Our work presents an important improvement towards easy CMC determination in small volume samples in comparison with the commonly used stalagmometric technique, where much larger sample volumes are usually needed. To date, the total surfactant concentration was not measured in the digestive juices of arthropods other than Homarus vulgaris, Astacus leptodactylus and Cancer pagurus, for which complex separation and analytical techniques were required. Our results obtained by SISE and PFM therefore present the first successful quantification of surfactants and their CMC in small volumes of arthropod digestive juice without prior separation or purification techniques. PMID:26969560

  17. Control of multiple arthropod vector infestations with subolesin/akirin vaccines.

    PubMed

    Moreno-Cid, Juan A; Pérez de la Lastra, José M; Villar, Margarita; Jiménez, Maribel; Pinal, Rocío; Estrada-Peña, Agustín; Molina, Ricardo; Lucientes, Javier; Gortázar, Christian; de la Fuente, José

    2013-02-01

    Diseases transmitted by arthropod vectors such as mosquitoes, ticks and sand flies greatly impact human and animal health and thus their control is important for the eradication of vector-borne diseases (VBD). Vaccination is an environmentally friendly alternative for vector control that allows control of several VBD by targeting their common vector. Recent results have suggested that subolesin/akirin (SUB/AKR) is good candidate antigens for the control of arthropod vector infestations. Here we describe the comparative effect of vaccination with SUB, AKR and Q38 and Q41 chimeras containing SUB/AKR conserved protective epitopes on tick, mosquitoes and sand flies vector mortality, molting, oviposition and/or fertility. We demonstrated that SUB vaccination had the highest efficacy (E) across all vector species (54-92%), Q41 vaccination had the highest vaccine E in mosquitoes (99%) by reducing female survival and fertility, and Q38 vaccination had the highest effect on reducing mosquito (28%) and sand fly (26%) oviposition. The effect of vaccination on different developmental processes in several important arthropod vectors encourages the development of SUB/AKR universal vaccines for the control of multiple vector infestations and reduction of VBD. PMID:23291476

  18. Subolesin/Akirin vaccines for the control of arthropod vectors and vectorborne pathogens.

    PubMed

    de la Fuente, J; Moreno-Cid, J A; Galindo, R C; Almazan, C; Kocan, K M; Merino, O; Perez de la Lastra, J M; Estrada-Peña, A; Blouin, E F

    2013-11-01

    Diseases transmitted by arthropod vectors such as mosquitoes, ticks and sand flies greatly impact human and animal health, and therefore, their control is important for the eradication of vectorborne diseases (VBD). Vaccination is an environmentally friendly alternative for vector control that allows control of several VBD by targeting their common vector. Recent results have suggested that subolesin (SUB) and its orthologue in insects, akirin (AKR) are good candidate antigens for the control of arthropod vector infestations and pathogen infection. SUB was discovered as a tick-protective antigen in Ixodes scapularis. Vaccination trials with recombinant SUB/AKR demonstrated effective control of arthropod vector infestations in various hard and soft tick species, mosquitoes, sand flies, poultry red mites and sea lice by reducing their numbers, weight, oviposition, fertility and/or moulting. SUB/AKR vaccination also reduced tick infection with tickborne pathogens, Anaplasma phagocytophilum, A. marginale, Babesia bigemina and Borrelia burgdorferi. The effect of vaccination on different hosts, vector species, developmental stages and vectorborne pathogen infections demonstrated the feasibility of SUB/AKR universal vaccines for the control of multiple vector infestations and for reduction in VBD. PMID:24589118

  19. Effects of land management strategies on the dispersal pattern of a beneficial arthropod.

    PubMed

    Marchi, Chiara; Andersen, Liselotte Wesley; Loeschcke, Volker

    2013-01-01

    Several arthropods are known to be highly beneficial to agricultural production. Consequently it is of great relevance to study the importance of land management and land composition for the conservation of beneficial aphid-predator arthropod species in agricultural areas. Therefore our study focusing on the beneficial arthropod Bembidion lampros had two main purposes: I) identifying the physical barriers to the species' dispersal in the agricultural landscape, and II) assessing the effect of different land management strategies (i.e. use of pesticides and intensiveness) on the dispersal patterns. The study was conducted using genetic analysis (microsatellite markers) applied to samples from two agricultural areas (in Denmark) with different agricultural intensity. Land management effects on dispersal patterns were investigated with particular focus on: physical barriers, use of pesticide and intensity of cultivation. The results showed that Bembidion lampros disperse preferably through hedges rather than fields, which act as physical barriers to gene flow. Moreover the results support the hypothesis that organic fields act as reservoirs for the re-colonization of conventional fields, but only when cultivation intensity is low. These results show the importance of non-cultivated areas and of low intensity organic managed areas within the agricultural landscape as corridors for dispersal (also for a species typically found within fields). Hence, the hypothesis that pesticide use cannot be used as the sole predictor of agriculture's effect on wild species is supported as land structure and agricultural intensity can be just as important. PMID:23776633

  20. Genetic and Ontogenetic Variation in an Endangered Tree Structures Dependent Arthropod and Fungal Communities

    PubMed Central

    Gosney, Benjamin J.; O′Reilly-Wapstra, Julianne M.; Forster, Lynne G.; Barbour, Robert C.; Iason, Glenn R.; Potts, Brad M.

    2014-01-01

    Plant genetic and ontogenetic variation can significantly impact dependent fungal and arthropod communities. However, little is known of the relative importance of these extended genetic and ontogenetic effects within a species. Using a common garden trial, we compared the dependent arthropod and fungal community on 222 progeny from two highly differentiated populations of the endangered heteroblastic tree species, Eucalyptus morrisbyi. We assessed arthropod and fungal communities on both juvenile and adult foliage. The community variation was related to previous levels of marsupial browsing, as well as the variation in the physicochemical properties of leaves using near-infrared spectroscopy. We found highly significant differences in community composition, abundance and diversity parameters between eucalypt source populations in the common garden, and these were comparable to differences between the distinctive juvenile and adult foliage. The physicochemical properties assessed accounted for a significant percentage of the community variation but did not explain fully the community differences between populations and foliage types. Similarly, while differences in population susceptibility to a major marsupial herbivore may result in diffuse genetic effects on the dependent community, this still did not account for the large genetic-based differences in dependent communities between populations. Our results emphasize the importance of maintaining the populations of this rare species as separate management units, as not only are the populations highly genetically structured, this variation may alter the trajectory of biotic colonization of conservation plantings. PMID:25469641

  1. Genetic and ontogenetic variation in an endangered tree structures dependent arthropod and fungal communities.

    PubMed

    Gosney, Benjamin J; O Reilly-Wapstra, Julianne M; Forster, Lynne G; Barbour, Robert C; Iason, Glenn R; Potts, Brad M

    2014-01-01

    Plant genetic and ontogenetic variation can significantly impact dependent fungal and arthropod communities. However, little is known of the relative importance of these extended genetic and ontogenetic effects within a species. Using a common garden trial, we compared the dependent arthropod and fungal community on 222 progeny from two highly differentiated populations of the endangered heteroblastic tree species, Eucalyptus morrisbyi. We assessed arthropod and fungal communities on both juvenile and adult foliage. The community variation was related to previous levels of marsupial browsing, as well as the variation in the physicochemical properties of leaves using near-infrared spectroscopy. We found highly significant differences in community composition, abundance and diversity parameters between eucalypt source populations in the common garden, and these were comparable to differences between the distinctive juvenile and adult foliage. The physicochemical properties assessed accounted for a significant percentage of the community variation but did not explain fully the community differences between populations and foliage types. Similarly, while differences in population susceptibility to a major marsupial herbivore may result in diffuse genetic effects on the dependent community, this still did not account for the large genetic-based differences in dependent communities between populations. Our results emphasize the importance of maintaining the populations of this rare species as separate management units, as not only are the populations highly genetically structured, this variation may alter the trajectory of biotic colonization of conservation plantings. PMID:25469641

  2. Global diversity patterns and cross-taxa convergence in freshwater systems.

    PubMed

    Tisseuil, Clement; Cornu, Jean-François; Beauchard, Olivier; Brosse, Sebastien; Darwall, William; Holland, Robert; Hugueny, Bernard; Tedesco, Pablo A; Oberdorff, Thierry

    2013-03-01

    Whereas global patterns and predictors of species diversity are well known for numerous terrestrial taxa, our understanding of freshwater diversity patterns and their predictors is much more limited. Here, we examine spatial concordance in global diversity patterns for five freshwater taxa (i.e. aquatic mammals, aquatic birds, fishes, crayfish and aquatic amphibians) and investigate the environmental factors driving these patterns at the river drainage basin grain. We find that species richness and endemism patterns are significantly correlated among taxa. We also show that cross-taxon congruence patterns are often induced by common responses of taxa to their contemporary and historical environments (i.e. convergent patterns). Apart from some taxa distinctiveness (i.e. fishes), the 'climate/productivity' hypothesis is found to explain the greatest variance in species richness and endemism patterns, followed by factors related to the 'history/dispersion' and 'area/environmental heterogeneity' hypotheses. As aquatic amphibians display the highest levels of congruency with other taxa, this taxon appears to be a good 'surrogate' candidate for developing global freshwater conservation planning at the river drainage basin grain. PMID:23173605

  3. MyTaxa: an advanced taxonomic classifier for genomic and metagenomic sequences

    PubMed Central

    Luo, Chengwei; Rodriguez-R, Luis M.; Konstantinidis, Konstantinos T.

    2014-01-01

    Determining the taxonomic affiliation of sequences assembled from metagenomes remains a major bottleneck that affects research across the fields of environmental, clinical and evolutionary microbiology. Here, we introduce MyTaxa, a homology-based bioinformatics framework to classify metagenomic and genomic sequences with unprecedented accuracy. The distinguishing aspect of MyTaxa is that it employs all genes present in an unknown sequence as classifiers, weighting each gene based on its (predetermined) classifying power at a given taxonomic level and frequency of horizontal gene transfer. MyTaxa also implements a novel classification scheme based on the genome-aggregate average amino acid identity concept to determine the degree of novelty of sequences representing uncharacterized taxa, i.e. whether they represent novel species, genera or phyla. Application of MyTaxa on in silico generated (mock) and real metagenomes of varied read length (100–2000 bp) revealed that it correctly classified at least 5% more sequences than any other tool. The analysis also showed that ∼10% of the assembled sequences from human gut metagenomes represent novel species with no sequenced representatives, several of which were highly abundant in situ such as members of the Prevotella genus. Thus, MyTaxa can find several important applications in microbial identification and diversity studies. PMID:24589583

  4. A swainsonine survey of North American Astragalus and Oxytropis taxa implicated as locoweeds.

    PubMed

    Cook, Daniel; Gardner, Dale R; Lee, Stephen T; Pfister, James A; Stonecipher, Clinton A; Welsh, Stanley L

    2016-08-01

    Swainsonine, an indolizidine alkaloid with significant physiological activity, is an α-mannosidase and mannosidase II inhibitor that causes lysosomal storage disease and alters glycoprotein processing. Swainsonine is found in a number of plant species worldwide, and causes severe toxicosis in livestock grazing these plants, leading to a chronic wasting disease characterized by weight loss, depression, altered behavior, decreased libido, infertility, and death. Swainsonine has been detected in 19 Astragalus and 2 Oxytropis species in North America by thin layer chromatography, gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry and a jack bean α-mannosidase inhibition assay. In addition, 5 species in North America are presumed to contain swainsonine based upon reports from field cases. Many of these plant species have not been analyzed for swainsonine using modern instrumentation such as gas or liquid chromatography coupled with mass spectrometry. To provide clarification, 22 Astragalus species representing 93 taxa and 4 Oxytropis species representing 18 taxa were screened for swainsonine using both liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. Swainsonine was detected in 48 Astragalus taxa representing 13 species and 5 Oxytropis taxa representing 4 species. Forty of the fifty-three swainsonine-positive taxa had not been determined to contain swainsonine previously using liquid or gas chromatography coupled with mass spectrometry. The list of swainsonine-containing taxa reported here will serve as a reference for risk assessment and diagnostic purposes. PMID:27085305

  5. Oxygen as a Driver of Early Arthropod Micro-Benthos Evolution

    PubMed Central

    Williams, Mark; Vannier, Jean; Corbari, Laure; Massabuau, Jean-Charles

    2011-01-01

    Background We examine the physiological and lifestyle adaptations which facilitated the emergence of ostracods as the numerically dominant Phanerozoic bivalve arthropod micro-benthos. Methodology/Principal Findings The PO2 of modern normoxic seawater is 21 kPa (air-equilibrated water), a level that would cause cellular damage if found in the tissues of ostracods and much other marine fauna. The PO2 of most aquatic breathers at the cellular level is much lower, between 1 and 3 kPa. Ostracods avoid oxygen toxicity by migrating to waters which are hypoxic, or by developing metabolisms which generate high consumption of O2. Interrogation of the Cambrian record of bivalve arthropod micro-benthos suggests a strong control on ecosystem evolution exerted by changing seawater O2 levels. The PO2 of air-equilibrated Cambrian-seawater is predicted to have varied between 10 and 30 kPa. Three groups of marine shelf-dwelling bivalve arthropods adopted different responses to Cambrian seawater O2. Bradoriida evolved cardiovascular systems that favoured colonization of oxygenated marine waters. Their biodiversity declined during intervals associated with black shale deposition and marine shelf anoxia and their diversity may also have been curtailed by elevated late Cambrian (Furongian) oxygen-levels that increased the PO2 gradient between seawater and bradoriid tissues. Phosphatocopida responded to Cambrian anoxia differently, reaching their peak during widespread seabed dysoxia of the SPICE event. They lacked a cardiovascular system and appear to have been adapted to seawater hypoxia. As latest Cambrian marine shelf waters became well oxygenated, phosphatocopids went extinct. Changing seawater oxygen-levels and the demise of much of the seabed bradoriid micro-benthos favoured a third group of arthropod micro-benthos, the ostracods. These animals adopted lifestyles that made them tolerant of changes in seawater O2. Ostracods became the numerically dominant arthropod micro-benthos of

  6. Near-future ocean acidification causes differences in microbial associations within diverse coral reef taxa.

    PubMed

    Webster, N S; Negri, A P; Flores, F; Humphrey, C; Soo, R; Botté, E S; Vogel, N; Uthicke, S

    2013-04-01

    Microorganisms form symbiotic partnerships with a diverse range of marine organisms and can be critical to the health and survival of their hosts. Despite the importance of these relationships, the sensitivity of symbiotic microbes to ocean acidification (OA) is largely unknown and this needs to be redressed to adequately predict marine ecosystem resilience in a changing climate. We adopted a profiling approach to explore the sensitivity of microbes associated with coral reef biofilms and representatives of three ecologically important calcifying invertebrate phyla [corals, foraminifera and crustose coralline algae (CCA)] to OA. The experimental design for this study comprised four pHs consistent with current IPCC predictions for the next few centuries (pHNIST 8.1, 7.9, 7.7, 7.5); these pH/pCO₂ conditions were produced in flow-through aquaria using CO₂ bubbling. All reduced pH/increased pCO₂ treatments caused clear differences in the microbial communities associated with coral, foraminifera, CCA and reef biofilms over 6 weeks, while no visible signs of host stress were detected over this period. The microbial communities of coral, foraminifera, CCA and biofilms were significantly different between pH 8.1 (pCO₂ = 464 μatm) and pH 7.9 (pCO₂ = 822 μatm), a concentration likely to be exceeded by the end of the present century. This trend continued at lower pHs/higher pCO₂. 16S rRNA gene sequencing revealed variable and species-specific changes in the microbial communities with no microbial taxa consistently present or absent from specific pH treatments. The high sensitivity of coral, foraminifera, CCA and biofilm microbes to OA conditions projected to occur by 2100 is a concern for reef ecosystems and highlights the need for urgent research to assess the implications of microbial shifts for host health and coral reef processes. PMID:23584968

  7. Micro-PIXE study of Ag in digestive glands of a nano-Ag fed arthropod ( Porcellio scaber, Isopoda, Crustacea)

    NASA Astrophysics Data System (ADS)

    Tkalec, Živa Pipan; Drobne, Damjana; Vogel-Mikuš, Katarina; Pongrac, Paula; Regvar, Marjana; Štrus, Jasna; Pelicon, Primož; Vavpetič, Primož; Grlj, Nataša; Remškar, Maja

    2011-10-01

    Micro-proton induced X-ray emission (micro-PIXE) method was applied to study the micro-localization of silver (Ag) in digestive glands of a terrestrial arthropod (Porcellio scaber) after feeding on silver nanoparticles (nano-Ag) dosed food. The aim of our work was to assess whether feeding on nano-Ag results in the assimilation of silver (Ag) in digestive gland cells. To study micro-localization and elemental distribution of Ag, the animals were fed on food dosed with nanoparticles for 14 days under controlled laboratory conditions. At the end of the feeding exposure, the animals were dissected and digestive glands prepared for micro-PIXE analyses and TEM investigation. The results obtained by micro-PIXE documented high amounts of Ag inside S-cells of the digestive gland epithelium; however, TEM investigation did not show particle aggregates inside digestive gland cells. Also no adverse effect on feeding behavior was recorded what is a measure of toxic effects. We explain the presence of Ag inside the cells as a result of the assimilation of dissoluted Ag ions from ingested nano-Ag particles. Assimilation of excessive amounts of ingested metal ions in S-cells is a well known metal detoxification mechanism in isopods. We discuss the advantages of using micro-PIXE for the micro-localization of elements in biological tissue in studies of interactions between nanoparticles and biological systems.

  8. Fungus gnats, Bradysia spp. (Diptera: Sciaridae), and other arthropods in commercial bagged soilless growing media and rooted plant plugs.

    PubMed

    Cloyd, Raymond A; Zaborski, Edmond R

    2004-04-01

    Fungus gnats, Bradysia spp., in greenhouses cause economic losses to horticultural producers by damaging young root systems during plant propagation, by spreading soilborne diseases, and by reducing the marketability of the crop. In a greenhouse cage study, our observations suggested that bagged soilless growing media or rooted plant plugs from wholesale distributors may be sources for the introduction of fungus gnats into commercial greenhouse facilities. To evaluate these possibilities, carefully collected samples of bagged soilless growing media stored in the greenhouse, as well as bagged soilless growing media and rooted plant plugs delivered from midwestern wholesale distributors, were incubated under controlled conditions in the laboratory. Fungus gnats emerged from soilless media stored in the greenhouse, soilless media delivered from wholesale distributors, and from rooted plant plugs delivered from wholesale distributors. These results demonstrate that pasteurization of even bagged soilless media may be essential to effectively managing greenhouse populations of fungus gnats. However, pasteurization is not an option for responding to contamination of rooted plant plugs. Preliminary evidence is provided that application of entomopathogenic nematodes may offer potential as a method for managing fungus gnats in plant plugs, so long as treatment is early. Other arthropods found contaminating soilless media and rooted plant plugs included the western flower thrips, Frankliniella occidentalis (Pergande), Collembola, Acari, Formicidae, Staphylinidae, Psychodidae, and other Diptera. PMID:15154474

  9. Populational survey of arthropods on transgenic common bean expressing the rep gene from Bean golden mosaic virus.

    PubMed

    Pinheiro, Patrícia V; Quintela, Eliane D; Junqueira, Ana Maria R; Aragão, Francisco J L; Faria, Josias C

    2014-01-01

    Genetically modified (GM) crops is considered the fastest adopted crop technology in the history of modern agriculture. However, possible undesirable and unintended effects must be considered during the research steps toward development of a commercial product. In this report we evaluated effects of a common bean virus resistant line on arthropod populations, considered as non-target organisms. This GM bean line (named M1/4) was modified for resistance against Bean golden mosaic virus (BGMV) by expressing a mutated REP protein, which is essential for virus replication. Biosafety studies were performed for a period of three years under field conditions. The abundance of some species was significantly higher in specific treatments in a particular year, but not consistently different in other years. A regular pattern was not observed in the distribution of insects between genetically modified and conventional treatments. Data analyses showed that minor differences observed can be attributed to random variation and were not consistent enough to conclude that the treatments were different. Therefore the present study indicates that the relative abundance of species are similar in transgenic and non-transgenic fields. PMID:24922280

  10. Reconstructing the Genomic Content of Microbiome Taxa through Shotgun Metagenomic Deconvolution

    PubMed Central

    Carr, Rogan; Shen-Orr, Shai S.; Borenstein, Elhanan

    2013-01-01

    Metagenomics has transformed our understanding of the microbial world, allowing researchers to bypass the need to isolate and culture individual taxa and to directly characterize both the taxonomic and gene compositions of environmental samples. However, associating the genes found in a metagenomic sample with the specific taxa of origin remains a critical challenge. Existing binning methods, based on nucleotide composition or alignment to reference genomes allow only a coarse-grained classification and rely heavily on the availability of sequenced genomes from closely related taxa. Here, we introduce a novel computational framework, integrating variation in gene abundances across multiple samples with taxonomic abundance data to deconvolve metagenomic samples into taxa-specific gene profiles and to reconstruct the genomic content of community members. This assembly-free method is not bounded by various factors limiting previously described methods of metagenomic binning or metagenomic assembly and represents a fundamentally different approach to metagenomic-based genome reconstruction. An implementation of this framework is available at http://elbo.gs.washington.edu/software.html. We first describe the mathematical foundations of our framework and discuss considerations for implementing its various components. We demonstrate the ability of this framework to accurately deconvolve a set of metagenomic samples and to recover the gene content of individual taxa using synthetic metage