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1

Opium poppy and Madagascar periwinkle: model non-model systems to investigate alkaloid biosynthesis in plants.  

PubMed

Alkaloids represent a large and diverse group of compounds that are related by the occurrence of a nitrogen atom within a heterocyclic backbone. Unlike other types of secondary metabolites, the various structural categories of alkaloids are unrelated in terms of biosynthesis and evolution. Although the biology of each group is unique, common patterns have become apparent. Opium poppy (Papaver somniferum), which produces several benzylisoquinoline alkaloids, and Madagascar periwinkle (Catharanthus roseus), which accumulates an array of monoterpenoid indole alkaloids, have emerged as the premier organisms used to study plant alkaloid metabolism. The status of these species as model systems results from decades of research on the chemistry, enzymology and molecular biology responsible for the biosynthesis of valuable pharmaceutical alkaloids. Opium poppy remains the only commercial source for morphine, codeine and semi-synthetic analgesics, such as oxycodone, derived from thebaine. Catharanthus roseus is the only source for the anti-cancer drugs vinblastine and vincristine. Impressive collections of cDNAs encoding biosynthetic enzymes and regulatory proteins involved in the formation of benzylisoquinoline and monoterpenoid indole alkaloids are now available, and the rate of gene discovery has accelerated with the application of genomics. Such tools have allowed the establishment of models that describe the complex cell biology of alkaloid metabolism in these important medicinal plants. A suite of biotechnological resources, including genetic transformation protocols, has allowed the application of metabolic engineering to modify the alkaloid content of these and related species. An overview of recent progress on benzylisoquinoline and monoterpenoid indole alkaloid biosynthesis in opium poppy and C. roseus is presented. PMID:18476877

Facchini, Peter J; De Luca, Vincenzo

2008-05-01

2

Expression patterns of genes involved in the defense and stress response of Spiroplasma citri infected Madagascar Periwinkle Catharanthus roseus.  

PubMed

Madagascar periwinkle is an ornamental and a medicinal plant, and is also an indicator plant that is highly susceptible to phytoplasma and spiroplasma infections from different crops. Periwinkle lethal yellows, caused by Spiroplasma citri, is one of the most devastating diseases of periwinkle. The response of plants to S. citri infection is very little known at the transcriptome level. In this study, quantitative real-time PCR (RT-qPCR) was used to investigate the expression levels of four selected genes involved in defense and stress responses in naturally and experimentally Spiroplasma citri infected periwinkles. Strictosidine ?-glucosidase involved in terpenoid indole alkaloids (TIAs) biosynthesis pathway showed significant upregulation in experimentally and naturally infected periwinkles. The transcript level of extensin increased in leaves of periwinkles experimentally infected by S. citri in comparison to healthy ones. A similar level of heat shock protein 90 and metallothionein expression was observed in healthy, naturally and experimentally spiroplasma-diseased periwinkles. Overexpression of Strictosidine ?-glucosidase demonstrates the potential utility of this gene as a host biomarker to increase the fidelity of S. citri detection and can also be used in breeding programs to develop stable disease-resistance varieties. PMID:22408455

Nejat, Naghmeh; Vadamalai, Ganesan; Dickinson, Matthew

2012-01-01

3

Expression Patterns of Genes Involved in the Defense and Stress Response of Spiroplasma citri Infected Madagascar Periwinkle Catharanthus roseus  

PubMed Central

Madagascar periwinkle is an ornamental and a medicinal plant, and is also an indicator plant that is highly susceptible to phytoplasma and spiroplasma infections from different crops. Periwinkle lethal yellows, caused by Spiroplasma citri, is one of the most devastating diseases of periwinkle. The response of plants to S. citri infection is very little known at the transcriptome level. In this study, quantitative real-time PCR (RT-qPCR) was used to investigate the expression levels of four selected genes involved in defense and stress responses in naturally and experimentally Spiroplasma citri infected periwinkles. Strictosidine ?-glucosidase involved in terpenoid indole alkaloids (TIAs) biosynthesis pathway showed significant upregulation in experimentally and naturally infected periwinkles. The transcript level of extensin increased in leaves of periwinkles experimentally infected by S. citri in comparison to healthy ones. A similar level of heat shock protein 90 and metallothionein expression was observed in healthy, naturally and experimentally spiroplasma-diseased periwinkles. Overexpression of Strictosidine ?-glucosidase demonstrates the potential utility of this gene as a host biomarker to increase the fidelity of S. citri detection and can also be used in breeding programs to develop stable disease-resistance varieties. PMID:22408455

Nejat, Naghmeh; Vadamalai, Ganesan; Dickinson, Matthew

2012-01-01

4

Ornamental Exterior versus Therapeutic Interior of Madagascar Periwinkle (Catharanthus roseus): The Two Faces of a Versatile Herb  

PubMed Central

Catharanthus roseus (L.) known as Madagascar periwinkle (MP) is a legendary medicinal plant mostly because of possessing two invaluable antitumor terpenoid indole alkaloids (TIAs), vincristine and vinblastine. The plant has also high aesthetic value as an evergreen ornamental that yields prolific blooms of splendid colors. The plant possesses yet another unique characteristic as an amiable experimental host for the maintenance of the smallest bacteria found on earth, the phytoplasmas and spiroplasmas, and serves as a model for their study. Botanical information with respect to synonyms, vernacular names, cultivars, floral morphology, and reproduction adds to understanding of the plant while the geography and ecology of periwinkle illustrate the organism's ubiquity. Good agronomic practices ensure generous propagation of healthy plants that serve as a source of bioactive compounds and multitudinous horticultural applications. The correlation between genetic diversity, variants, and TIA production exists. MP is afflicted with a whole range of diseases that have to be properly managed. The ethnobotanical significance of MP is exemplified by its international usage as a traditional remedy for abundant ailments and not only for cancer. TIAs are present only in micro quantities in the plant and are highly poisonous per se rendering a challenge for researchers to increase yield and reduce toxicity. PMID:25667940

Valdiani, Alireza; Cahill, David; Tan, Yee-How; Maziah, Mahmood; Abiri, Rambod

2015-01-01

5

Ornamental exterior versus therapeutic interior of Madagascar periwinkle (Catharanthus roseus): the two faces of a versatile herb.  

PubMed

Catharanthus roseus (L.) known as Madagascar periwinkle (MP) is a legendary medicinal plant mostly because of possessing two invaluable antitumor terpenoid indole alkaloids (TIAs), vincristine and vinblastine. The plant has also high aesthetic value as an evergreen ornamental that yields prolific blooms of splendid colors. The plant possesses yet another unique characteristic as an amiable experimental host for the maintenance of the smallest bacteria found on earth, the phytoplasmas and spiroplasmas, and serves as a model for their study. Botanical information with respect to synonyms, vernacular names, cultivars, floral morphology, and reproduction adds to understanding of the plant while the geography and ecology of periwinkle illustrate the organism's ubiquity. Good agronomic practices ensure generous propagation of healthy plants that serve as a source of bioactive compounds and multitudinous horticultural applications. The correlation between genetic diversity, variants, and TIA production exists. MP is afflicted with a whole range of diseases that have to be properly managed. The ethnobotanical significance of MP is exemplified by its international usage as a traditional remedy for abundant ailments and not only for cancer. TIAs are present only in micro quantities in the plant and are highly poisonous per se rendering a challenge for researchers to increase yield and reduce toxicity. PMID:25667940

Nejat, Naghmeh; Valdiani, Alireza; Cahill, David; Tan, Yee-How; Maziah, Mahmood; Abiri, Rambod

2015-01-01

6

A 7-Deoxyloganetic Acid Glucosyltransferase Contributes a Key Step in Secologanin Biosynthesis in Madagascar Periwinkle[C][W][OPEN  

PubMed Central

Iridoids form a broad and versatile class of biologically active molecules found in thousands of plant species. In addition to the many hundreds of iridoids occurring in plants, some iridoids, such as secologanin, serve as key building blocks in the biosynthesis of thousands of monoterpene indole alkaloids (MIAs) and many quinoline alkaloids. This study describes the molecular cloning and functional characterization of three iridoid glucosyltransfeases (UDP-SUGAR GLYCOSYLTRANSFERASE6 [UGT6], UGT7, and UGT8) from Madagascar periwinkle (Catharanthus roseus) with remarkably different catalytic efficiencies. Biochemical analyses reveal that UGT8 possessed a high catalytic efficiency toward its exclusive iridoid substrate, 7-deoxyloganetic acid, making it better suited for the biosynthesis of iridoids in periwinkle than the other two iridoid glucosyltransfeases. The role of UGT8 in the fourth to last step in secologanin biosynthesis was confirmed by virus-induced gene silencing in periwinkle plants, which reduced expression of this gene and resulted in a large decline in secologanin and MIA accumulation within silenced plants. Localization studies of UGT8 using a carborundum abrasion method for RNA extraction show that its expression occurs preferentially within periwinkle leaves rather than in epidermal cells, and in situ hybridization studies confirm that UGT8 is preferentially expressed in internal phloem associated parenchyma cells of periwinkle species. PMID:24104568

Asada, Keisuke; Salim, Vonny; Masada-Atsumi, Sayaka; Edmunds, Elizabeth; Nagatoshi, Mai; Terasaka, Kazuyoshi; Mizukami, Hajime; De Luca, Vincenzo

2013-01-01

7

Molecular and Biochemical Analysis of a Madagascar Periwinkle Root-Specific Minovincinine-19-Hydroxy-O-Acetyltransferase1  

PubMed Central

The terminal steps in the biosynthesis of the monoterpenoid indole alkaloids vindoline and minovincinine are catalyzed by separate acetyl coenzyme A-dependent O-acetyltransferases in Madagascar periwinkle (Catharanthus roseus G. Don). Two genes were isolated that had 63% nucleic acid identity and whose deduced amino acid sequences were 78% identical. Active enzymes that were expressed as recombinant His-tagged proteins in Escherichia coli were named minovincinine-19-O-acetyltransferase (MAT) and deacetylvindoline-4-O-acetyltransferase (DAT) because they catalyzed the 19-O-acetylation of indole alkaloids such as minovincinine and hörhammericine and the 4-O-acetylation of deacetylvindoline, respectively. Kinetic studies showed that the catalytic efficiency of recombinant MAT (rMAT) was very poor compared with that of recombinant DAT (rDAT), whose turnover rates for Acetyl-coenzyme A and deacetylvindoline were approximately 240- and 10,000-fold greater than those of rMAT. Northern-blot analyses showed that MAT is expressed in cortical cells of the root tip, whereas DAT is only expressed in specialized idioblast and laticifer cells within light exposed tissues like leaves and stems. The coincident expression of trytophan decarboxylase, strictosidine synthase, and MAT within root cortical cells suggests that the entire pathway for the biosynthesis of tabersonine and its substituted analogs occurs within these cells. The ability of MAT to catalyze the 4-O-acetylation of deacetylvindoline with low efficiency suggests that this enzyme, rather than DAT, is involved in vindoline biosynthesis within transformed cell and root cultures, which accumulate low levels of this alkaloid under certain circumstances. PMID:11154328

Laflamme, Pierre; St-Pierre, Benoit; De Luca, Vincenzo

2001-01-01

8

Nuclear factors GT1 and 3AF1 interact with multiple sequences within the promoter of the Tdc gene from Madagascar periwinkle: GT1 is involved in UV light-induced expression  

Microsoft Academic Search

Plant secondary metabolites of the terpenoid indole alkaloid (TIA) class comprise several compounds with pharmaceutical applications.\\u000a A key step in the TIA biosynthetic pathway is catalysed by the enzyme tryptophan decarboxylase (TDC), which channels the primary\\u000a metabolite tryptophan into TIA metabolism. In Catharanthus roseus (Madagascar periwinkle), the Tdc gene is expressed throughout plant development. Moreover, Tdc gene expression is induced

P. B. F. Ouwerkerk; T. O. Trimborn; F. Hilliou; J. Memelink

1999-01-01

9

The Complete Plastid Genome Sequence of Madagascar Periwinkle Catharanthus roseus (L.) G. Don: Plastid Genome Evolution, Molecular Marker Identification, and Phylogenetic Implications in Asterids  

PubMed Central

The Madagascar periwinkle (Catharanthusroseus in the family Apocynaceae) is an important medicinal plant and is the source of several widely marketed chemotherapeutic drugs. It is also commonly grown for its ornamental values and, due to ease of infection and distinctiveness of symptoms, is often used as the host for studies on phytoplasmas, an important group of uncultivated plant pathogens. To gain insights into the characteristics of apocynaceous plastid genomes (plastomes), we used a reference-assisted approach to assemble the complete plastome of C. roseus, which could be applied to other C. roseus-related studies. The C. roseus plastome is the second completely sequenced plastome in the asterid order Gentianales. We performed comparative analyses with two other representative sequences in the same order, including the complete plastome of Coffeaarabica (from the basal Gentianales family Rubiaceae) and the nearly complete plastome of Asclepiassyriaca (Apocynaceae). The results demonstrated considerable variations in gene content and plastome organization within Apocynaceae, including the presence/absence of three essential genes (i.e., accD, clpP, and ycf1) and large size changes in non-coding regions (e.g., rps2-rpoC2 and IRb-ndhF). To find plastome markers of potential utility for Catharanthus breeding and phylogenetic analyses, we identified 41 C. roseus-specific simple sequence repeats. Furthermore, five intergenic regions with high divergence between C. roseus and three other euasterids I taxa were identified as candidate markers. To resolve the euasterids I interordinal relationships, 82 plastome genes were used for phylogenetic inference. With the addition of representatives from Apocynaceae and sampling of most other asterid orders, a sister relationship between Gentianales and Solanales is supported. PMID:23825699

Ku, Chuan; Chung, Wan-Chia; Chen, Ling-Ling; Kuo, Chih-Horng

2013-01-01

10

Madagascar 1  

NSDL National Science Digital Library

You will follow the directions of your teacher as you move through these different maps. Here is a link to the explanation of the project for teachers: Madagascar Explanation 1 You should have two copies of this map: Blank madagascar map to complete the exercise. Here's how you add a document from MyUEN to your IA project: Using UEN to link to a document from the IA Watch this movie about Madagascar. Think about where on this ...

Brooke Robertshaw

2010-02-17

11

Madagascar 2  

NSDL National Science Digital Library

You will follow the directions of your teacher as you move through these different maps. Here is a link to the explanation of the project for teachers: Madagascar explanation You should have two copies of this map: Blank madagascar map to complete the exercise. Here's how you add a document from MyUEN to your IA project: Using UEN to link to a document from the IA Watch this movie about Madagascar. Think about where on this ...

Mr. Olsen

2010-02-23

12

Pattern of diversity for morphological and alkaloid yield related traits among the periwinkle Catharanthus roseus accessions collected from in and around Indian subcontinent  

Microsoft Academic Search

Thirty two accessions of periwinkle Catharanthus roseus collected from different semitemperate to tropical geographical areas of Indian subcontinent, Madagascar, Singapore and Malaysia were characterized under field conditions for 53 growth, development, morphogenesis and alkaloid yield related characters over a few seasons at Lucknow, India. Large differences were observed among the accessions for each of the characters examined. The differences among

Parul Mishra; G. C. Uniyal; S. Sharma; Sushil Kumar

2001-01-01

13

Does Diversity Matter In Modeling? Testing A New Version Of The FORMIX3 Growth Model For Madagascar Rainforests  

NASA Astrophysics Data System (ADS)

Ecological forecasting has become an essential tool used by ecologists to understand the dynamics of growth and disturbance response in threatened ecosystems such as the rainforests of Madagascar. In the species rich tropics, forest conservation is often eclipsed by anthropogenic factors, resulting in a heightened need for accurate assessment of biomass before these ecosystems disappear. The objective of this study was to test a new Madagascar rainforest specific version of the FORMIX3 growth model (Huth and Ditzer, 2000; Huth et al 1998) to assess how accurately biomass can be simulated in high biodiversity forests using a method of functional type aggregation in an individual-based model framework. Rainforest survey data collected over three growing seasons, including 265 tree species, was aggregated into 12 plant functional types based on size and light requirements. Findings indicated that the forest study site compared best when the simulated forest reached mature successional status. Multiple level comparisons between model simulation data and survey plot data found that though some features, such as the dominance of canopy emergent species and relative absence of small woody treelets are captured by the model, other forest attributes were not well reflected. Overall, the ability to accurately simulate the Madagascar rainforest was slightly diminished by the aggregation of tree species into size and light requirement functional type groupings.

Armstrong, A. H.; Fischer, R.; Shugart, H. H.; Huth, A.

2012-12-01

14

Rapid Identification of Enzyme Variants for Reengineered Alkaloid Biosynthesis in Periwinkle  

PubMed Central

Summary Monoterpene indole alkaloids from Catharanthus roseus (Madagascar periwinkle), such as the anticancer agents vinblastine and vincristine, have important pharmacological activities. Metabolic engineering of alkaloid biosynthesis can provide an efficient and environmentally friendly route to analogs of these synthetically challenging and pharmaceutically valuable natural products. However, the narrow substrate scope of strictosidine synthase, the enzyme at the entry point of the pathway, limits a pathway engineering approach. We demonstrate that with a new expression system and screening method it is possible to rapidly identify strictosidine synthase variants that accept tryptamine analogs not turned over by the wild-type enzyme. The variants are used in stereoselective synthesis of ?-carboline analogs and assessed for biosynthetic competence within the terpene indole alkaloid pathway. These results present an opportunity to explore metabolic engineering of “unnatural” product production in the plant periwinkle. PMID:17719488

Bernhardt, Peter; McCoy, Elizabeth; O’Connor, Sarah E.

2009-01-01

15

A necessarily complex model to explain the biogeography of the amphibians and reptiles of Madagascar.  

PubMed

Pattern and process are inextricably linked in biogeographic analyses, though we can observe pattern, we must infer process. Inferences of process are often based on ad hoc comparisons using a single spatial predictor. Here, we present an alternative approach that uses mixed-spatial models to measure the predictive potential of combinations of hypotheses. Biodiversity patterns are estimated from 8,362 occurrence records from 745 species of Malagasy amphibians and reptiles. By incorporating 18 spatially explicit predictions of 12 major biogeographic hypotheses, we show that mixed models greatly improve our ability to explain the observed biodiversity patterns. We conclude that patterns are influenced by a combination of diversification processes rather than by a single predominant mechanism. A 'one-size-fits-all' model does not exist. By developing a novel method for examining and synthesizing spatial parameters such as species richness, endemism and community similarity, we demonstrate the potential of these analyses for understanding the diversification history of Madagascar's biota. PMID:25297804

Brown, Jason L; Cameron, Alison; Yoder, Anne D; Vences, Miguel

2014-01-01

16

Deforestation and Rice: Using Methods in Modeling and Remote Sensing to Project Patterns of Forest Change in Eastern Madagascar  

NASA Astrophysics Data System (ADS)

In the species rich tropics, forest conservation is often eclipsed by anthropogenic disturbance, resulting in a heightened need for an accurate assessment of biomass and the gaining of predictive capability before these ecosystems disappear. The combination of multi-temporal remote sensing data, field data and forest growth modeling to quantify carbon stocks and flux is therefore of great importance. In this study, we utilize these methods to (1) improve forest biomass and carbon flux estimates for the study region in Eastern Madagascar, and (2) initialize an individual-based growth model that incorporates the anthropogenic factors causing deforestation to project ecosystem response to future environmental change. Recent studies have shown that there is a direct correlation between the international rice market and rates of deforestation in tropical countries such as Madagascar (see Minten et al., 2006). Further, although law protects the remaining forest areas, dictatorships and recent political unrest have lead to poor or non-existent enforcement of precious wood and forest protection over the past 35 years. Our approach combined multi-temporal remote sensing analysis and ecological modeling using a theoretical and mathematical approach to assess biomass change and to understand how tree growth and life history (growth response patterns) relate to past and present economic variability in Madagascar forests of the eastern Toamasina region. We measured rates of change of deforestation with respect to politics and the price of rice by classifying and comparing biomass using 30m Landsat during 5 political regime time periods (1985-1992, 1993-1996, 1997-2001, 2002-2008, 2009 to present). Forest biomass estimations were calibrated using forest inventory data collected over 3 growing seasons over the study region (130 small circular plots in primary forest). This information was then built into the previously parameterized (Armstrong et al., in prep and Fischer et al in review) Madagascar FORMIX3 Model (see Huth and Ditzer, 2000) by incorporating rice economy, selective logging and political stability modules into the model to control certain species groups (i.e. selective harvest) and fire frequency (encroachment). The improved FORMIX3 model was then used to investigate and project forest growth response to a variety of impact scenarios ranging from an increase in overall deforestation to a decrease in deforestation and increase in protection enforcement. Our findings showed a significant positive correlation between increasing deforestation rates and higher local rice prices due to political regime and international market factors. This research resulted in the first quantitative analysis of the relationship between the international rice market and local land-use in terms of slash and burn agriculture, illegal logging of precious hardwood in Madagascar.

Armstrong, A. H.; Fatoyinbo, T. E.; Fischer, R.; Huth, A.; Shugart, H. H.

2013-12-01

17

Stone tools and foraging in northern Madagascar challenge Holocene extinction models  

PubMed Central

Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar’s known occupational history, and thus the time during which people exploited Madagascar’s environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. 14C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton’i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050–1350, by 14C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. 14C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact. PMID:23858456

Dewar, Robert E.; Radimilahy, Chantal; Wright, Henry T.; Jacobs, Zenobia; Kelly, Gwendolyn O.; Berna, Francesco

2013-01-01

18

Phase equilibrium modeling of Pan-African incipient charnockite from southern Madagascar  

NASA Astrophysics Data System (ADS)

Dark brownish patches and/or veins of coarse-grained orthopyroxene-bearing felsic granulite (charnockite) within foliated amphibolite-facies gneiss/migmatite, are considered as examples of 'metamorphic' charnockite, and represent the transformation of amphibolite-facies rocks to dry granulites on a local scale. Such 'incipient' charnockites have been reported so far from many localities in southern India and Sri Lanka which corresponds to the central part of the East African - Antarctic Orogenic Belt related to the assembly of the Gondwana Supercontinent. Detailed petrological investigations of incipient charnockites therefore provide important insights into granulite-forming processes in the lower crust during Neoproterozoic to Cambrian. Here, we report the first occurrence of incipient charnockite from Ihosy area in southern Madagascar, and discuss the petrogenesis of granulite formation in an arrested stage on the basis of petrography, geothermobarometry, fluid inclusion study, and mineral equilibrium modeling. In the study area, patches of brownish charnockite (Pl+ Qtz + Kfs + Bt + Grt + Opx + Ilm + Mag) of about 20 to 50 cm in length occur within host orthopyroxene-free garnet-biotite gneiss (Pl + Qtz + Kfs + Bt + Grt + Ilm + Mag). The application of mineral equilibrium modeling on charnockite assemblage in NCKFMASHTO system to constrain the conditions of charnockitization defines a P - T range of 8-10.5 kbar and 820-880° C, which is broadly consistent with the results from the conventional geothermobarometry (820-880° C at 9 kbar) on Grt-Bt gneiss. The result of T versus mole H2O (M(H2O)) modeling demonstrated that orthopyroxene-free assemblage in Grt-Bt gneiss is stable only at M(H2O) >0.1 mol.%, while orthopyroxene in charnockite occurs as a stable mineral at very low M(H2O) condition of

Tsunogae, Toshiaki; Endo, Takahiro; Santosh, Mw; Thierry Rakotonandrasana, N. O.; Shaji, Erath; Rambeloson, Roger A.

2013-04-01

19

Stone tools and foraging in northern Madagascar challenge Holocene extinction models.  

PubMed

Past research on Madagascar indicates that village communities were established about AD 500 by people of both Indonesian and East African heritage. Evidence of earlier visits is scattered and contentious. Recent archaeological excavations in northern Madagascar provide evidence of occupational sites with microlithic stone technologies related to foraging for forest and coastal resources. A forager occupation of one site dates to earlier than 2000 B.C., doubling the length of Madagascar's known occupational history, and thus the time during which people exploited Madagascar's environments. We detail stratigraphy, chronology, and artifacts from two rock shelters. Ambohiposa near Iharana (Vohémar) on the northeast coast, yielded a stratified assemblage with small flakes, microblades, and retouched crescentic and trapezoidal tools, probably projectile elements, made on cherts and obsidian, some brought more that 200 km. (14)C dates are contemporary with the earliest villages. No food remains are preserved. Lakaton'i Anja near Antsiranana in the north yielded several stratified assemblages. The latest assemblage is well dated to A.D. 1050-1350, by (14)C and optically stimulated luminescence dating and pottery imported from the Near East and China. Below is a series of stratified assemblages similar to Ambohiposa. (14)C and optically stimulated luminescence dates indicate occupation from at least 2000 B.C. Faunal remains indicate a foraging pattern. Our evidence shows that foragers with a microlithic technology were active in Madagascar long before the arrival of farmers and herders and before many Late Holocene faunal extinctions. The differing effects of historically distinct economies must be identified and understood to reconstruct Holocene histories of human environmental impact. PMID:23858456

Dewar, Robert E; Radimilahy, Chantal; Wright, Henry T; Jacobs, Zenobia; Kelly, Gwendolyn O; Berna, Francesco

2013-07-30

20

Cryopreservation of periwinkle, Catharanthus roseus cells cultured in vitro  

Microsoft Academic Search

A procedure for prolonged cryogenic storage of periwinkle cell cultures is described. Cells derived from periwinkle, Catharanthus roseus (L.) G. Don, and subcultured as suspension in 1-B5C nutrient medium have been frozen, stored in liquid nitrogen (-196°C) for 11 weeks, thawed and recultured. Maximal survival was achieved when 3–4 day-old cells precultured for 24 h in nutrient medium with 5%

K. K. Kartha; N. L. Leung; P. Gaudet-LaPrairie; F. Constabel

1982-01-01

21

The possibility of using photogrammetric and remote sensing techniques to model lavaka (gully erosion) development in Madagascar  

NASA Astrophysics Data System (ADS)

Gully erosion is a worldwide problem for it has a number of undesirable effects and their development is hard to follow. Madagascar is one of the most affected countries for its highlands are densely covered with gullies named lavakas. Lavaka formation and development seems to be triggered by many regional and local causes but the actual reasons are still poorly understood. Furthermore lavakas differ from normal gullies due to their enormous size and special shape. Field surveys are time consuming and data from two-dimensional measurements and pictures (even aerial) might lack major information for morphologic studies. Therefore close range surveying technologies should be used to get three-dimensional information about these unusual and complex features. This contribution discusses which remote sensing and photogrammetric techniques are adequate to survey the development of lavakas, their volume change and sediment budget. Depending on the types and properties (such as volume, depth, shape, vegetation) of the lavaka different methods will be proposed showing pros and cons of each one of them. Our goal is to review techniques to model, survey and analyze lavakas development to better understand the cause of their formation, special size and shape. Different methods are evaluated and compared from field survey through data processing, analyzing cost-effectiveness, potential errors and accuracy for each one of them. For this purpose we will also consider time- and cost-effectiveness of the softwares able to render the images into 3D model as well as the resolution and accuracy of the outputs. Further studies will concentrate on using the three dimensional models of lavakas which will be later on used for geomorphological studies in order to understand their special shape and size. This is ILARG-contribution #07.

Raveloson, Andrea; Székely, Balázs; Molnár, Gábor; Rasztovits, Sascha

2013-04-01

22

A null model for species richness gradients: bounded range overlap of butterflies and other rainforest endemics in Madagascar  

Microsoft Academic Search

Species richness has classically been thought to increase from the poles towards the Equator, and from high elevations down to sea-level. However, the largest radiation of butterflies in Madagascar, the subtribe Mycalesina (c. 67 spp.) does not exhibit such a monotonic pattern, either for empirical records or for interpolated species ranges. Instead, summation of mycalesine ranges generates a domed curve

DAVID C LEES; CLAIRE KREMEN; LANTO ANDRIAMAMPIANINA

1999-01-01

23

A spatially explicit metapopulation model and cattle trade analysis suggests key determinants for the recurrent circulation of rift valley Fever virus in a pilot area of madagascar highlands.  

PubMed

Rift Valley fever (RVF) is a vector-borne zoonotic disease that causes high morbidity and mortality in ruminants. In 2008-2009, a RVF outbreak affected the whole Madagascar island, including the Anjozorobe district located in Madagascar highlands. An entomological survey showed the absence of Aedes among the potential RVF virus (RVFV) vector species identified in this area, and an overall low abundance of mosquitoes due to unfavorable climatic conditions during winter. No serological nor virological sign of infection was observed in wild terrestrial mammals of the area, suggesting an absence of wild RVF virus (RVFV) reservoir. However, a three years serological and virological follow-up in cattle showed a recurrent RVFV circulation. The objective of this study was to understand the key determinants of this unexpected recurrent transmission. To achieve this goal, a spatial deterministic discrete-time metapopulation model combined with cattle trade network was designed and parameterized to reproduce the local conditions using observational data collected in the area. Three scenarios that could explain the RVFV recurrent circulation in the area were analyzed: (i) RVFV overwintering thanks to a direct transmission between cattle when viraemic cows calve, vectors being absent during the winter, (ii) a low level vector-based circulation during winter thanks to a residual vector population, without direct transmission between cattle, (iii) combination of both above mentioned mechanisms. Multi-model inference methods resulted in a model incorporating both a low level RVFV winter vector-borne transmission and a direct transmission between animals when viraemic cows calve. Predictions satisfactorily reproduced field observations, 84% of cattle infections being attributed to vector-borne transmission, and 16% to direct transmission. These results appeared robust according to the sensitivity analysis. Interweaving between agricultural works in rice fields, seasonality of vector proliferation, and cattle exchange practices could be a key element for understanding RVFV circulation in this area of Madagascar highlands. PMID:25474116

Nicolas, Gaëlle; Chevalier, Véronique; Tantely, Luciano Michaël; Fontenille, Didier; Durand, Benoît

2014-12-01

24

A Spatially Explicit Metapopulation Model and Cattle Trade Analysis Suggests Key Determinants for the Recurrent Circulation of Rift Valley Fever Virus in a Pilot Area of Madagascar Highlands  

PubMed Central

Rift Valley fever (RVF) is a vector-borne zoonotic disease that causes high morbidity and mortality in ruminants. In 2008–2009, a RVF outbreak affected the whole Madagascar island, including the Anjozorobe district located in Madagascar highlands. An entomological survey showed the absence of Aedes among the potential RVF virus (RVFV) vector species identified in this area, and an overall low abundance of mosquitoes due to unfavorable climatic conditions during winter. No serological nor virological sign of infection was observed in wild terrestrial mammals of the area, suggesting an absence of wild RVF virus (RVFV) reservoir. However, a three years serological and virological follow-up in cattle showed a recurrent RVFV circulation. The objective of this study was to understand the key determinants of this unexpected recurrent transmission. To achieve this goal, a spatial deterministic discrete-time metapopulation model combined with cattle trade network was designed and parameterized to reproduce the local conditions using observational data collected in the area. Three scenarios that could explain the RVFV recurrent circulation in the area were analyzed: (i) RVFV overwintering thanks to a direct transmission between cattle when viraemic cows calve, vectors being absent during the winter, (ii) a low level vector-based circulation during winter thanks to a residual vector population, without direct transmission between cattle, (iii) combination of both above mentioned mechanisms. Multi-model inference methods resulted in a model incorporating both a low level RVFV winter vector-borne transmission and a direct transmission between animals when viraemic cows calve. Predictions satisfactorily reproduced field observations, 84% of cattle infections being attributed to vector-borne transmission, and 16% to direct transmission. These results appeared robust according to the sensitivity analysis. Interweaving between agricultural works in rice fields, seasonality of vector proliferation, and cattle exchange practices could be a key element for understanding RVFV circulation in this area of Madagascar highlands. PMID:25474116

Nicolas, Gaëlle; Chevalier, Véronique; Tantely, Luciano Michaël; Fontenille, Didier; Durand, Benoît

2014-01-01

25

Madagascar Fauna Group  

NSDL National Science Digital Library

This is the homepage of the Madagascar Fauna Group, an "international consortium of zoos and related organizations that pool their talents and resources to work together in one of the world's most endangered places." Readers will find loads of information about the island and its diverse assortment of animal species, many of which are "bizarrely beautiful" and found nowhere else. The site also offers a number of Web links for general information about Madagascar, educational sites about lemurs and other animals, and links geared towards kids.

26

Investigating the Lithospheric Structure of Southern Madagascar  

NASA Astrophysics Data System (ADS)

The island of Madagascar occupies a key region in both the assembly and the multi-stage breakup of Gondwanaland, itself part of the super-continent Pangaea. Madagascar consists of an amalgamation of continental material, with the oldest rocks being of Archaean age. Its ancient fabric is characterised by several shear zones, some of them running oblique to the N-S trend, in particular in the south of the island. More recently during the Neogene, moderate volcanism has occurred in the Central and Northern part of the island, and there are indications of uplift throughout Eastern Madagascar over the last 10 Ma. Although Madagascar is now located within the interior of the African plate and far away from major plate boundaries (> 1000 km from the East African rift system and even further from the Central and South-West Indian Ridges), its seismic activity indicates that some deformation is taking place, and present-day kinematic models based on geodetic data and earthquake moment tensors in the global catalogues identify a diffuse N-S-oriented minor boundary separating two microplates, which appears to pass through Madagascar. In spite of the presence of Archaean and Proterozoic rocks continent-wide scale studies indicate a thin lithosphere (<120 km) throughout Madagascar, but are based on sparse data and cannot resolve the difference between eastern and western Madagascar. We are operating a ENE-WSW oriented linear array of 25 broadband stations in southern Madagascar, extending from coast to coast and sampling the sedimentary basins in the west as well as the metamorphic rocks in the East, cutting geological boundaries seen at the surface at high angle. The array crosses the prominent Bongolava-Ranotsara shear zone which is thought to have been formed during Gondwanaland assembly. The array recorded the magnitude 5.3 earthquake of January 25, 2013 which occurred just off its western edge. In addition, in May 2013 we have deployed 25 short period sensors in the eastern part of the study area, where there is some so-far poorly characterised seismicity. We will present preliminary results on the lithospheric crust and mantle structure based on surface wave dispersion and waveform modelling, focussing on the contrast between the metamorphic areas in the east and the presumably stretched regions in the west. Station distribution Red diamonds: Temporary Broadband Light red squares: Short period Green: permanent stations Other temporary experiments: Open dark blue boxes: RHUM-RUM stations Open light blue boxes: MACOMO stations

Tilmann, F. J.; Yuan, X.; Rumpker, G.; Heit, B.; Rambolamana, G.; Rindraharisaona, E.; Priestley, K. F.

2013-12-01

27

Responses of Mud Snails and Periwinkles to Environmental Odors and Disaccharide Mimics of Fish Odor  

Microsoft Academic Search

Estuarine snails, periwinkles (Littoraria irorata), and mud snails (Ilyanassa obsoleta) were tested for behavioral responses to aqueous extracts of tissue macerates, odors of living intact organisms, and to disaccharides derived from heparin. Extracts included salt-marsh cordgrass (Spartina alterniflora), pink shrimp (Penaeus duorarum), crushed periwinkles, and crushed mud snails. Odors included live periwinkles, mud snails, stone crab (Menippe mercenaria), striped hermit

Yasmin J. Rahman; Richard B. Forward; Dan Rittschof

2000-01-01

28

Trigonalidae (Hymenoptera) of Madagascar  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seven species of the primarily hyperparasitoid family Trigonalidae are reported from Madagascar: Orthogonalys brevis Smith and Tripotin, sp. n., Orthogonalys gigantea Benoit, 1951; O. hova Bischoff, 1933; O. maculata Bischoff, 1933; Orthogonalys parahova Smith and Tripotin, sp. n., O. seyrigi Bisch...

29

Mammalian biodiversity on Madagascar controlled by ocean currents.  

PubMed

Madagascar hosts one of the world's most unusual, endemic, diverse and threatened concentrations of fauna. To explain its unique, imbalanced biological diversity, G. G. Simpson proposed the 'sweepstakes hypothesis', according to which the ancestors of Madagascar's present-day mammal stock rafted there from Africa. This is an important hypothesis in biogeography and evolutionary theory for how animals colonize new frontiers, but its validity is questioned. Studies suggest that currents were inconsistent with rafting to Madagascar and that land bridges provided the migrants' passage. Here we show that currents could have transported the animals to the island and highlight evidence inconsistent with the land-bridge hypothesis. Using palaeogeographic reconstructions and palaeo-oceanographic modelling, we find that strong surface currents flowed from northeast Mozambique and Tanzania eastward towards Madagascar during the Palaeogene period, exactly as required by the 'sweepstakes process'. Subsequently, Madagascar advanced north towards the equatorial gyre and the regional current system evolved into its modern configuration with flows westward from Madagascar to Africa. This may explain why no fully non-aquatic land mammals have colonized Madagascar since the arrival of the rodents and carnivorans during the early-Miocene epoch. One implication is that rafting may be the dominant means of overseas dispersal in the Cenozoic era when palaeocurrent directions are properly considered. PMID:20090678

Ali, Jason R; Huber, Matthew

2010-02-01

30

The Madagascar Hissing Cockroach: A New Model for Learning Insect Anatomy  

ERIC Educational Resources Information Center

Teaching and learning animal anatomy has a long history in the biology classroom. As in many fields of biology, decades of experience teaching anatomy have led to the unofficial selection of model species. However, in some cases the model may not be the best choice for our students. Our struggle to find an appropriate model for teaching and…

Heyborne, William H.; Fast, Maggie; Goodding, Daniel D.

2012-01-01

31

Exploiting alkaloid biosynthesis in Madagascar periwinkle to obtain natural product derivatives and new biocatalysts  

E-print Network

Plant alkaloid biosynthesis produces many natural products with medicinal value. For example, vinblastine and vincristine from Catharanthus roseus monoterpene indole alkaloid biosynthesis, and camptothecin derivatives from ...

Bernhardt, Peter, Ph. D. Massachusetts Institute of Technology

2010-01-01

32

Onilahy River, Madagascar  

NASA Technical Reports Server (NTRS)

Near the southern tip of Madagascar, the Onilahy River (23.5S, 44E) drains a near barren landscape, the result of rapid deforestation for quick profits from the lumber industry with no regard to the environmental impact. At the turn of the century, the island was a lush tropical paradise with about 90 percent of the surface forested. Now, at the close of the century, only about 10 percent of the forests remain in inaccessible rugged terrain.

1982-01-01

33

Madagascar Hissing Cockroaches: Information and Care  

E-print Network

Madagascar Hissing Cockroaches: Information and Care L-278 The Madagascar hissing cockroach or classroom project information on the biology and care of the Madagascar hissing cockroach. Description and Biology The Madagascar hissing cockroach (MHC) is approximately 2 to 4 inches long and weighs 1/4 to 7

Balasundaram, Balabhaskar "Baski"

34

A Habit of the Common Periwinkle (littorina littorea Linn.)  

Microsoft Academic Search

AN interesting habit of the common periwinkle, Littorina littorea Linnæus, which does not appear to have been recorded by previous writers, is worthy of some attention. On boulder-strewn shores, such as that at Penrhyn Bay, North Wales, where these observations were made, this species may occur in enormous numbers at and below the half-tide level in situations devoid of the

D. P. Wilson

1929-01-01

35

Digestive enzymes of the saltmarsh periwinkle Littorina irrorata (Mollusca: Gastropoda)  

Microsoft Academic Search

The saltmarsh periwinkleLittorina irrorata is well adapted for the digestion of a wide range of polysaccharides. Enzyme extracts attacked cellulose, pectin, xylan, bean gum and mannan (common in cell walls of higher plants), as well as starch and laminarin (representative of major polysaccharide classes in fungal, algal, and animal tissues). Activities were generally highes at a ph of 5 or

Felix Bärlocher; Thomas L. Arsuffi; Steven Y. Newell

1989-01-01

36

Effects of barnacle epibionts on the periwinkle Littorina littorea (L.)  

Microsoft Academic Search

In a sandy bay with mussel beds in the Wadden Sea (Island of Sylt, eastern North Sea), periwinkles Littorina littorea (L.) were often strongly overgrown with the barnacle Balanus crenatus Bruguière in the lower intertidal zone. Consequences of this epibiosis on mobility, reproduction and mortalityof the snail\\u000a were examined. B. crenatus growing on L. littorea increased snail volume up to

C. Buschbaum; K. Reise

1999-01-01

37

Pathogenicity of Aster Yellows Phytoplasma and Spiroplasma citri on Periwinkle.  

PubMed

ABSTRACT Using Murashige and Skoog (MS) as a basal medium, the effects of varying levels and combinations of plant growth regulators required for shoot tip and root proliferation in healthy and aster yellows phytoplasma (AYP)- and Spiroplasma citri-infected periwinkle (Catharanthus roseus) shoots were studied. Number of shoots and fresh and dry mass of healthy and AYP-infected shoots increased when benzyladenine (BA) concentrations were increased from 0.5 to 4 mg/liter. The maximum number of shoots for both healthy and AYP-infected plants was obtained when grown in MS medium supplemented with BA at 4 mg/liter and indole-3-acetic acid (IAA) at 0.5 mg/liter. S. citri-infected shoots proliferated the most when grown in MS medium containing BA at 2 mg/liter and IAA at 0.5 mg/liter. The best medium for root production in healthy periwinkle shoots contained alpha-naphthaleneacetic acid (NAA) at 0.5 mg/liter, whereas the best medium for AYP-infected shoots contained indole-3-butyric acid (IBA) at 2.5 mg/liter, both in combination with kinetin at 0.1 mg/liter. S. citri-infected shoots had the best root growth when grown in medium supplemented with IBA at 5.0 mg/liter and kinetin at 0.1 mg/liter. The concentration of cytokinin and auxin needed for maximum shoot proliferation differed between AYP- and S. citri-infected shoot tips, strongly indicating that the two mollicutes may cause different changes in endogenous cytokinin and auxin levels. The concentrations of NAA and IBA needed for root growth of S. citri-infected shoots were two- to fivefold higher than the concentrations needed for healthy and AYP-infected shoots, clearly demonstrating that S. citri infection caused a shortage of auxins that resulted in retardation of secondary root growth. Chlorophyll content was markedly reduced in periwinkles infected with AYP or S. citri compared with chlorophyll in healthy periwinkles. AYP caused a decrease in carotenoid in leaves 6 weeks after graft-inoculation, but carotenoid content was unchanged in S. citri-infected leaves throughout the test period. Anthocyanin content in periwinkles infected with AYP decreased significantly by 4 weeks postinoculation, whereas anthocyanin content in periwinkles infected with S. citri increased. Anthocyanin content in leaf tissues, however, was reduced as a result of AYP and S. citri infection. Pigment changes induced by AYP and S. citri, whether similar or different compared with those of healthy periwinkle shoots, provide important information for interpreting pathogenesis when linked with plant growth regulators. PMID:18944838

Chang, C J

1998-12-01

38

Oceanography of West Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Along selected hydrographical transects, a total of 182 CTD stations were conducted and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, along the west and south coast of Madagascar, the shelf is narrow and widen slightly along the north-west coast. In all ten transects the isotherms showed stratified waters from the coast to offshore. A maximum salinity layer was observed at subsurface in all transects. Dissolved oxygen had a maximum at around 500 m depth in all transects. Low fluorescence values were observed in the upper 150-200 m, with maximum values in the range of 0.14-0.22 µg/l at intermediate layers. The conditions were consistent along and between the transects, with more variation observed at transect 9. No upwelling was observed along the western coast. The surface temperature (5 m depth) increased from 22°C in the south to 26°C in the north. The horizontal distribution of surface salinities showed homogenous conditions with values between 35.4psu (south) and 35.0 psu (north). Also starting from the coast to offshore, both the surface temperatures and surface salinities showed homogenous patterns.

John, Bemiasa

2014-05-01

39

The amino acid and stable isotope biogeochemistry of elephant bird (Aepyornis) eggshells from southern Madagascar  

Microsoft Academic Search

A diverse suite of animals became extinct on Madagascar during the Late Holocene. As observed on landmasses elsewhere, the extinction process broadly coincided with the arrival of people. Our research on the amino acid racemisation and the carbon and oxygen isotope biogeochemistry of elephant bird (Aepyornis) eggshells from southern Madagascar refines models that attempt to explain the extinction process. A

Simon J. Clarke; Gifford H. Miller; Marilyn L. Fogel; Allan R. Chivas; Colin V. Murray-Wallace

2006-01-01

40

The amino acid and stable isotope biogeochemistry of elephant bird ( Aepyornis) eggshells from southern Madagascar  

Microsoft Academic Search

A diverse suite of animals became extinct on Madagascar during the Late Holocene. As observed on landmasses elsewhere, the extinction process broadly coincided with the arrival of people. Our research on the amino acid racemisation and the carbon and oxygen isotope biogeochemistry of elephant bird (Aepyornis) eggshells from southern Madagascar refines models that attempt to explain the extinction process. A

Simon J. Clarke; Gifford H. Miller; Marilyn L. Fogel; Allan R. Chivas; Colin V. Murray-Wallace

2006-01-01

41

Un cadre de modlisation dynamique multiniveau pour la peste bubonique des Hautes Terres de Madagascar  

E-print Network

persistance enzootique de la peste. Keywords Bubonic plague ­ Madagascar ­ Dynamic Modeling ­ Multi applied to the bubonic plague of the Highlands of Madagascar, which incorporates the heterogeneity of plague epizootic invasion and enzootic persistence. Introduction La peste bubonique est une zoonose

Boyer, Edmond

42

Annual report 2005 Baobabs, Madagascar  

E-print Network

and service units 58-59 IRD establishments around the world 60Rice terraces #12;Other assignments Distribution'Ivoire South Africa La Réunion Madagascar Kenya Indonesia New Caledonia Thailand Vietnam Laos Cameroon Egypt

43

Zooplankton of West Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - October 2009) in Western and Northern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. Zooplankton samples were collected with Hydrobios Multinet at all environmental stations ranging from 200 m depth to the surface. The Multinet was equipped with 5 nets for depth-stratified sampling. The nets were fitted with 180 µm mesh size and the water flow through the nets was measured. The Multinet was deployed and retrieved at a rate of ~ 1.5 m per second and was obliquely hauled. The five nets were triggered at the pre-selected depth intervals 0-25m, 25-50m, 50-80m, 80-120m and 120-200m. All samples were stored in marked bottles and preserved with buffered formaldehyde of 4% for further analysis. As results,the zooplankton abundance was influenced by physico-chemical factors. During the study period 34 Family of zooplankton were identified which are dominated by Copepoda (58,69%) followed by Radiolaria (12,06%), Appendicularia (6,47%), Sagitta (5,11%), Larvae (4,57%), Ostracoda (3,13%), pelagic Foraminifera (2,15%). Family of zooplankton with abundance <1% were also recorded, namely Salpidae (0,94%), Euphausiacea (0,44%), Tintinnidae (0,39%), Annélidae Polychètes (0,34%), Mysidacea (0,21%), Ptéropodae (0,13%). Highest number of zooplankton were found at the depth below the maximum of fluorescence during the day. Copepods distribution depends on site and depth. During this study, the number of identified species is always superior to 50 for all sampling sites. The findings of the present study will help to improve the scientific knowledge of the marine ecosystem of the west coast of Madagascar.

Bemiasa, John; Remanevy, Sitraka

2014-05-01

44

Microgeographical shell variation in Littorina striata , a planktonic developing periwinkle  

Microsoft Academic Search

Littorina striata is a strictly Macaronesian, intertidal periwinkle with planktonic development. The species produces both nodulose and smooth\\u000a shells, which co-occur at Ilheu de Vila Franca do Campo, a drowned crater situated about 1000?m off the south coast of So\\u000a Miguel, Azores. The present work describes and analyzes the shell variation, temporal change and ecological distribution of\\u000a the two shell

H. De Wolf; T. Backeljau; R. Medeiros; R. Verhagen

1997-01-01

45

Effect of Seafoods (Periwinkle, Bonkafish and Crayfish) and Vegetable Oils Enriched Meal on Cardiovascular Disease  

Microsoft Academic Search

Periwinkle (Tympanotonus fustcatus), Crayfish (cambarellus diminutus) and Bonka fish (Ethimalosa fimbriata) are local marine food sources of omega-3 fatty acid. Groundnut oil, corn oil and soybean oil are notably high in omega-6 fatty acids. The present study compared changes in haematological and biochemical indices in rats fed with local marine foods (periwinkle, bonka fish and crayfish) and vegetable oils (groundnut,

J. I. Ndem; M. I. Akpanabiatu; E. U. Essien

2008-01-01

46

Investigating the Lithospheric Structure of Southern Madagascar  

NASA Astrophysics Data System (ADS)

The island of Madagascar occupies a key region in both the assembly and the multi-stage breakup of Gondwanaland, itself part of the super-continent Pangaea. Madagascar consists of an amalgamation of continental material, with the oldest rocks being of Archaean age. Its ancient fabric is characterised by several shear zones, some of them running oblique to the N-S trend, in particular in the south of the island. More recently during the Neogene, moderate volcanism has occurred in the Central and Northern part of the island, and there are indications of uplift throughout Eastern Madagascar over the last 10 Ma. Although Madagascar is now located within the interior of the African plate and far away from major plate boundaries (> 1000 km from the East African rift system and even further from the Central and South-West Indian Ridges), its seismic activity indicates that some deformation is taking place, and present-day kinematic models based on geodetic data and earthquake moment tensors in the global catalogues identify a diffuse N-S-oriented minor boundary separating two microplates, which appears to pass through Madagascar. In spite of the presence of Archaean and Proterozoic rocks continent-wide scale studies indicate a thin lithosphere (<120 km) throughout Madagascar, but are based on sparse data. We are operating a ENE-WSW oriented linear array of 25 broadband stations in southern Madagascar, extending from coast to coast and sampling the sedimentary basins in the west as well as the metamorphic rocks in the East, cutting geological boundaries seen at the surface at high angle. The array crosses the prominent Bongolava-Ranotsara shear zone which is thought to have been formed during Gondwanaland assembly, although this interpretation has recently been questioned. The array recorded the magnitude 5.3 earthquake of January 25, 2013 which occurred just off its western edge. In addition, in May 2013 we have deployed 25 short period sensors in the eastern part of the study area, where there is some so-far poorly characterised seismicity. We present preliminary results on the lithospheric crust and mantle structure based on surface wave dispersion and waveform modelling, focussing on the contrast between the metamorphic areas in the east and the presumably stretched regions in the west. Interstation Green's functions have been obtained from all pairs of vertical broadband records, with coherent Rayleigh waves being identifiable for periods of 3-40 s. In addition, two-station phase dispersion measurements have allowed us to determine phase dispersion between 25 and 60 s. The ambient noise and earthquake data both indicate a slow-down of surface propagation in the western part of the array for periods < 40-45 s, but faster propagation in the western part for periods >45 s.

Tilmann, Frederik; Yuan, Xiaohui; Rümpker, Georg; Gerard, Rambolamana; Elisa, Rindraharisaona; Priestley, Keith

2014-05-01

47

Madagascar: Heads It's a Continent, Tails It's an Island  

NASA Astrophysics Data System (ADS)

Neither geologists nor biologists have a definition that is capable of classifying Madagascar unambiguously as an island or a continent; nor can they incorporate Malagasy natural history into a single model rooted in Africa or Asia. Madagascar is a microcosm of the larger continents, with a rock record that spans more than 3000 million years (Ma), during which it has been united episodically with, and divorced from, Asian and African connections. This is reflected in its Precambrian history of deep crustal tectonics and a Phanerozoic history of biodiversity that fluctuated between cosmopolitanism and parochialism. Both vicariance and dispersal events over the past 90 Ma have blended a unique endemism on Madagascar, now in decline following rapid extinctions that started about 2000 years ago.

de Wit, Maarten J.

48

Oceanography of East Madagascar  

NASA Astrophysics Data System (ADS)

During six week survey (August - September 2008) in Southern and Eastern coast of Madagascar, the R/V 'Dr. Fridtjof Nansen' has carried out a study of the pelagic ecosystem. In collaboration with Agulhas & Somali Current Large Marine Ecosystems project (ASCLME) and South West Indian Ocean Fisheries Project (SWIOFP), the aim of the survey was to establish the physical, chemical and biological characteristics of the Western Madagascar shelf region as a whole. A total of 102 CTD stations were conducted along selected hydrographical transects and ranged to a maximum of 3000 m depth. Water samples were also collected with Niskin bottles at predefined depths. A Seabird 911plus CTD was used to obtain vertical profiles of temperature, salinity and oxygen. As results, the first section between latitude 25o-26oS showed sea surface temperature values ranging between 25oC to 15oC upper 250m depth. As part of the south-west, the shelf is narrow and widen slightly along the tip south of the Island coast. In contrast of the west coast, in all transects performed along the south and the east coast, in most cases, the isotherms showed non stratified waters from the coast to offshore. The presence of the upwelling system in the south-east coast modifies drastically the patterns of all measured parameters. Fluorescence had a maximum values (0.25 µg/l) at surface near the coast in 2nd to 5th transects. Inversely, low temperature values were observed along the south and south-east with minimum values in the range of 18. 5oC-11oC at 50-250 m depth. These conditions were consistent along and between the 2nd to 5th transects, with more variation observed at transect 5. The salinity values (5 m depth) decreased from 35.7 psu in the south to 34.5 psu in the east. The horizontal distribution of oxygen showed non homogenous conditions with values between 5 ml/l (south) and 2.5 ml/l (south-east). Also starting from the coast to offshore, surface temperatures and surface salinities, surface fluorescence and dissolved oxygen showed non homogenous patterns.

Bemiasa, John

2014-05-01

49

Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009  

E-print Network

Viral Etiology of Influenza-Like Illnesses in Antananarivo, Madagascar, July 2008 to June 2009 Influenza Centre, Institut Pasteur de Madagascar (IPM), Antananarivo, Madagascar, 2 Epidemiology Unit, IPM, Antananarivo, Madagascar Abstract Background: In Madagascar, despite an influenza surveillance established

Paris-Sud XI, Université de

50

Resistances et initiatives a Madagascar (Resistance and Initiatives in Madagascar).  

ERIC Educational Resources Information Center

Discusses the cultural, political, and institutional barriers to population education in Madagascar and the strategies and initiatives that have been adopted to overcome them, including emphasizing the national character of a project, accommodating the values and ideals of the people involved, and assuring teachers of their classroom autonomy.…

Georges, Claude

1993-01-01

51

Ecological Effects of the Invasive Giant Madagascar Day Gecko on Endemic Mauritian Geckos: Applications of Binomial-Mixture and Species Distribution Models  

PubMed Central

The invasion of the giant Madagascar day gecko Phelsuma grandis has increased the threats to the four endemic Mauritian day geckos (Phelsuma spp.) that have survived on mainland Mauritius. We had two main aims: (i) to predict the spatial distribution and overlap of P. grandis and the endemic geckos at a landscape level; and (ii) to investigate the effects of P. grandis on the abundance and risks of extinction of the endemic geckos at a local scale. An ensemble forecasting approach was used to predict the spatial distribution and overlap of P. grandis and the endemic geckos. We used hierarchical binomial mixture models and repeated visual estimate surveys to calculate the abundance of the endemic geckos in sites with and without P. grandis. The predicted range of each species varied from 85 km2 to 376 km2. Sixty percent of the predicted range of P. grandis overlapped with the combined predicted ranges of the four endemic geckos; 15% of the combined predicted ranges of the four endemic geckos overlapped with P. grandis. Levin's niche breadth varied from 0.140 to 0.652 between P. grandis and the four endemic geckos. The abundance of endemic geckos was 89% lower in sites with P. grandis compared to sites without P. grandis, and the endemic geckos had been extirpated at four of ten sites we surveyed with P. grandis. Species Distribution Modelling, together with the breadth metrics, predicted that P. grandis can partly share the equivalent niche with endemic species and survive in a range of environmental conditions. We provide strong evidence that smaller endemic geckos are unlikely to survive in sympatry with P. grandis. This is a cause of concern in both Mauritius and other countries with endemic species of Phelsuma. PMID:24785293

Buckland, Steeves; Cole, Nik C.; Aguirre-Gutiérrez, Jesús; Gallagher, Laura E.; Henshaw, Sion M.; Besnard, Aurélien; Tucker, Rachel M.; Bachraz, Vishnu; Ruhomaun, Kevin; Harris, Stephen

2014-01-01

52

Ecological effects of the invasive giant madagascar day gecko on endemic mauritian geckos: applications of binomial-mixture and species distribution models.  

PubMed

The invasion of the giant Madagascar day gecko Phelsuma grandis has increased the threats to the four endemic Mauritian day geckos (Phelsuma spp.) that have survived on mainland Mauritius. We had two main aims: (i) to predict the spatial distribution and overlap of P. grandis and the endemic geckos at a landscape level; and (ii) to investigate the effects of P. grandis on the abundance and risks of extinction of the endemic geckos at a local scale. An ensemble forecasting approach was used to predict the spatial distribution and overlap of P. grandis and the endemic geckos. We used hierarchical binomial mixture models and repeated visual estimate surveys to calculate the abundance of the endemic geckos in sites with and without P. grandis. The predicted range of each species varied from 85 km2 to 376 km2. Sixty percent of the predicted range of P. grandis overlapped with the combined predicted ranges of the four endemic geckos; 15% of the combined predicted ranges of the four endemic geckos overlapped with P. grandis. Levin's niche breadth varied from 0.140 to 0.652 between P. grandis and the four endemic geckos. The abundance of endemic geckos was 89% lower in sites with P. grandis compared to sites without P. grandis, and the endemic geckos had been extirpated at four of ten sites we surveyed with P. grandis. Species Distribution Modelling, together with the breadth metrics, predicted that P. grandis can partly share the equivalent niche with endemic species and survive in a range of environmental conditions. We provide strong evidence that smaller endemic geckos are unlikely to survive in sympatry with P. grandis. This is a cause of concern in both Mauritius and other countries with endemic species of Phelsuma. PMID:24785293

Buckland, Steeves; Cole, Nik C; Aguirre-Gutiérrez, Jesús; Gallagher, Laura E; Henshaw, Sion M; Besnard, Aurélien; Tucker, Rachel M; Bachraz, Vishnu; Ruhomaun, Kevin; Harris, Stephen

2014-01-01

53

The culture history of Madagascar  

Microsoft Academic Search

Madagascar's culture is a unique fusion of elements drawn from the western, northern, and eastern shores of the Indian Ocean, and its past has fascinated many scholars, yet systematic archaeological research is relatively recent on the island. The oldest traces of visitors are from the first century AD. Coastal settlements, with clear evidence of ties to the western Indian Ocean

Robert E. Dewar; Henry T. Wright

1993-01-01

54

Effects of barnacle epibionts on the periwinkle Littorina littorea (L.)  

NASA Astrophysics Data System (ADS)

In a sandy bay with mussel beds in the Wadden Sea (Island of Sylt, eastern North Sea), periwinkles Littorina littorea (L.) were often strongly overgrown with the barnacle Balanus crenatus Bruguière in the lower intertidal zone. Consequences of this epibiosis on mobility, reproduction and mortalityof the snail were examined. B. crenatus growing on L. littorea increased snail volume up to 4-fold and weight up to 3.5-fold and crawling speed of fouled L. littorea was significantly slowed down. The epibiotic structure also caused a decrease in reproductive output. In laboratory experiments, egg production of fouled L. littorea was significantly lower than in snails free of barnacles. Presumably, copulation of the periwinkles is hampered by the voluminous and prickly cover of barnacles. Field studies demonstrated an increased mortality of overgrown L. littorea. A decrease in reproductive output and a lower survival of snails with a cover of barnacles suggest that B. crenatus epibionts may have a significant impact on the population of L. littorea.

Buschbaum, C.; Reise, K.

55

Growth of the salt marsh periwinkle Littoraria irrorata on fungal and cordgrass diets  

Microsoft Academic Search

The growth of the salt marsh periwinkleLittoraria irrorata (collected from Sapelo Island, Georgia in 1991, initial shell length 6.2 to 11.5 mm) on various diets was measured. Growth was highest on a diet of standing-dead leaves ofSpartina alterniflora. Periwinkles provided with marsh sediment, yellow-green, sterile, or bacteria-colonized leaves lost organic mass. Fungal-colonized leaves and pure mycelia of fungi common on

F. Bärlocher; S. Y. Newell

1994-01-01

56

Habitat-specific size structure variations in periwinkle populations ( Littorina littorea) caused by biotic factors  

Microsoft Academic Search

Shell size distribution patterns of marine gastropod populations may vary considerably across different environments. We investigated\\u000a the size and density structure of genetically continuous periwinkle populations (Littorina littorea) on an exposed rocky and a sheltered sedimentary environment on two nearby islands in the south-eastern North Sea (German\\u000a Bight). On the sedimentary shore, periwinkle density (917 ± 722 individuals m?2) was about three

Nina Eschweiler; Markus Molis; Christian Buschbaum

2009-01-01

57

Effect of periwinkles shell particle size on the wear behavior of asbestos free brake pad  

NASA Astrophysics Data System (ADS)

The effect of periwinkle shell particle size on the wear behavior of asbestos free brake pad has been investigated. The asbestos free brake pad produced by varying the periwinkle shell particles was from +125 to +710 ?m with phenolic resin as the binder. The wear test was performed using pin on disk machine by varying the sliding speed, applied load, temperatures and periwinkle shell particle size. Full factorial design of four factor-two levels and analysis of variance were used in the study of the wear test. The results shown that wear rate increases with increasing the sliding speed, load, temperatures and periwinkle particle size. The co-efficient of friction obtained is within the recommended standard for automobile brake pad. The +125 ?m particles of periwinkles gave the best wear resistance. Factorial design of the experiment can be successfully employed to describe the wear behavior of the samples and developed linear equation for predicting wear rate within selected experimental conditions. The results of this research indicate that periwinkle shell particles can be effectively used as a replacement for asbestos in brake pad manufacture.

Amaren, S. G.; Yawas, D. S.; Aku, S. Y.

58

Ionic alkylleads in salt marsh periwinkles (Littorina irrorata)  

SciTech Connect

Salt marsh periwinkles (Littorina irrorata), from six sites in Maryland and Virginia, were examined to determine ionic alkyllead concentrations and possible alkyllead sources in lower Chesapeake Bay. Different sources of ethylleads and trimethyllead to this species were demonstrated by statistical comparisons of the concentrations of individual analytes from different sites. These comparisons also indicated (1) that environmentally mediated methylation of Pb/sup 2 +/ contributes appreciably to Me/sub 3/Pb/sup +/ concentrations in snails and (2) that the relative concentrations of individual analytes were consistent with an environmental methylation of ethyllead salts. Compared to females, males were characterized by significantly higher concentrations of several of the alkyllead analytes. In addition, an unknown lead-containing compound was present in all samples.

Krishnan, K.; Marshall, W.D.; Hatch, W.I.

1988-07-01

59

Leptospirosis after a stay in madagascar.  

PubMed

We report a case of polymerase chain reaction (PCR)-confirmed leptospirosis in a patient who recently traveled to Madagascar, a country where only two cases have been reported since 1955. Although laboratory and clinical presentations were atypical and despite leptospirosis not being a documented disease in Madagascar, blood and urine tests for leptospirosis enabled retrospective confirmation of the diagnosis. PMID:25319525

Pagès, Frédéric; Kuli, Barbara; Moiton, Marie-Pierre; Goarant, Cyrille; Jaffar-Bandjee, Marie-Christine

2015-03-01

60

Discovery, characterization, and rational design of the enzymes involved in monoterpene indole alkaloid biosynthesis in Madagascar periwinkle  

E-print Network

The chemical diversity found in plants has served as a major source of inspiration to many synthetic and biological chemists. Nature has evolved enzyme active sites to catalyze the synthesis of structurally complex compounds ...

Giddings, Lesley-Ann

2011-01-01

61

Seed transmission of Candidatus Liberibacter asiaticus in periwinkle and dodder resulted in low bacterial titer and very mild disease in periwinkle  

Technology Transfer Automated Retrieval System (TEKTRAN)

Canadidatus Liberibacter asiaticus (Las) is the most widely-distributed of three species of Liberibacter that are associated with citrus Huanglongbing (HLB), a lethal disease of citrus worldwide. In addition to citrus, periwinkle (Catharanthus roseus) and dodder (Cuscuta pentagona) are two experime...

62

Large scale population structure and gene flow in the planktonic developing periwinkle, Littorina striata, in Macaronesia (Mollusca: Gastropoda)  

Microsoft Academic Search

Allozymes were used to investigate the genetic structure of 42 populations of the planktonic developing, Macaronesian periwinkle Littorina striata, throughout its entire geographic range (Azores, Madeira, Canary Islands and Cape Verde Islands). This periwinkle is presumed to have a high dispersal and gene flow potential, because it has a planktonic development. It is therefore expected to show little population genetic

Hans De Wolf; Ron Verhagen; Thierry Backeljau

2000-01-01

63

Effect of cytokinin on alkaloid accumulation in periwinkle callus cultures transformed with a light-inducible ipt gene  

Microsoft Academic Search

The effect of cytokinins on accumulation of indole alkaloids in periwinkle callus cultures was investigated. Firstly, it was found that exogenously-applied cytokinin increased the ajmalicine and serpentine content of untransformed callus culture obtained from cotyledons. Secondly, periwinkle cotyledons were transformed with the isopentenyl transferase (ipt) gene under the control of a light-inducible promoter and two transformed callus lines were used

Frédérique Garnier; Sabine Carpin; Philippe Label; Joel Crèche; Marc Rideau; Saïd Hamdi

1996-01-01

64

Imperfect Isolation: Factors and Filters Shaping Madagascar’s Extant Vertebrate Fauna  

PubMed Central

Analyses of phylogenetic topology and estimates of divergence timing have facilitated a reconstruction of Madagascar’s colonization events by vertebrate animals, but that information alone does not reveal the major factors shaping the island’s biogeographic history. Here, we examine profiles of Malagasy vertebrate clades through time within the context of the island’s paleogeographical evolution to determine how particular events influenced the arrival of the island’s extant groups. First we compare vertebrate profiles on Madagascar before and after selected events; then we compare tetrapod profiles on Madagascar to contemporary tetrapod compositions globally. We show that changes from the Mesozoic to the Cenozoic in the proportions of Madagascar’s tetrapod clades (particularly its increase in the representation of birds and mammals) are tied to changes in their relative proportions elsewhere on the globe. Differences in the representation of vertebrate classes from the Mesozoic to the Cenozoic reflect the effects of extinction (i.e., the non-random susceptibility of the different vertebrate clades to purported catastrophic global events 65 million years ago), and new evolutionary opportunities for a subset of vertebrates with the relatively high potential for transoceanic dispersal potential. In comparison, changes in vertebrate class representation during the Cenozoic are minor. Despite the fact that the island’s isolation has resulted in high vertebrate endemism and a unique and taxonomically imbalanced extant vertebrate assemblage (both hailed as testimony to its long isolation), that isolation was never complete. Indeed, Madagascar’s extant tetrapod fauna owes more to colonization during the Cenozoic than to earlier arrivals. Madagascar’s unusual vertebrate assemblage needs to be understood with reference to the basal character of clades originating prior to the K-T extinction, as well as to the differential transoceanic dispersal advantage of other, more recently arriving clades. Thus, the composition of Madagascar’s endemic vertebrate assemblage itself provides evidence of the island's paleogeographic history. PMID:23626770

Samonds, Karen E.; Godfrey, Laurie R.; Ali, Jason R.; Goodman, Steven M.; Vences, Miguel; Sutherland, Michael R.; Irwin, Mitchell T.; Krause, David W.

2013-01-01

65

Dipoles of the South East Madagascar Current  

NASA Astrophysics Data System (ADS)

Satellite altimetry data covering 18 years together with hydrographic observations around south Madagascar show that after separation from the coast, the South East Madagascar Current (SEMC) propagates southwestward and breaks up into a regular series of symmetric counter-rotating vortex pairs. Most of them split and propagate into the Agulhas retroflection system. Interannual variability of the dipole formation is related to the El Nino-Southern Oscillation. In the observation period two "early" Agulhas retroflection events appeared both related to strong Madagascar dipoles. The symmetry of the dipoles may originate from the boundary current where negative vorticity on the inshore side is adjacent to positive vorticity further offshore.

Ridderinkhof, W.; Le Bars, D.; Heydt, A. S.; Ruijter, W. P. M.

2013-02-01

66

Eating the dead in Madagascar.  

PubMed

Cannibalism has been poorly understood and has seldom been studied, since it was often suppressed by missionaries and colonial administrators, and very few societies still practise it. Cannibalistic practices are more complex than was originally thought. They may be supported in societies under stress or in times of famine, to reflect aggression and antisocial behaviour (in cases where the bodies of enemies killed in battle or people who have harmed the family are eaten), or to honour a dead kinsman. It was, for example, noted in Madagascar during the imperial campaigns of Ranavalona I in the period 1829 - 1853. Two types of cannibalism have been described: exocannibalism, where enemies were consumed, and endocannibalism, where dead relatives were eaten to assist their passing to the world of the ancestors, or to prolong contact with beloved and admired family members and absorb their good qualities. This article reviews some of the beliefs and motivations that surrounded the cannibalistic practices of the people of Madagascar in the 19th century.  PMID:24300654

Campbell, Gwyn

2013-12-01

67

Habitat-specific size structure variations in periwinkle populations ( Littorina littorea) caused by biotic factors  

NASA Astrophysics Data System (ADS)

Shell size distribution patterns of marine gastropod populations may vary considerably across different environments. We investigated the size and density structure of genetically continuous periwinkle populations ( Littorina littorea) on an exposed rocky and a sheltered sedimentary environment on two nearby islands in the south-eastern North Sea (German Bight). On the sedimentary shore, periwinkle density (917 ± 722 individuals m-2) was about three times higher than on the rocky shore (296 ± 168 individuals m-2). Mean (9.8 ± 3.9 mm) and maximum (22 mm) shell size of L. littorea on the sedimentary shore were smaller than on the rocky shore (21.5 ± 4.2 and 32 mm, respectively), where only few small snails were found. Additionally, periwinkle shells were thicker and stronger on the rocky than on the sedimentary shore. To ascertain mechanisms responsible for differences in population structures, we examined periwinkles in both environments for growth rate, predation pressure, infection with a shell boring polychaete ( Polydora ciliata) and parasitic infestation by trematodes. A crosswise transplantation experiment revealed better growth conditions on the sedimentary than on the rocky shore. However, crab abundance and prevalence of parasites and P. ciliata in adult snails were higher on the sedimentary shore. Previous investigations showed that crabs prefer large periwinkles infested with P. ciliata. Thus, we suggest that parasites and shell boring P. ciliata in conjunction with an increased crab predation pressure are responsible for low abundances of large periwinkles on the sedimentary shore while high wave exposure may explain low densities of juvenile L. littorea on the rocky shore. We conclude that biotic factors may strongly contribute to observed differences in size structure of the L. littorea populations studied on rocky and sedimentary shores.

Eschweiler, Nina; Molis, Markus; Buschbaum, Christian

2009-06-01

68

Micro-spatial distribution of two sibling periwinkle species across the intertidal indicates hybrdization.  

PubMed

Populations of periwinkles Littorina saxatilis (Olivi 1792) and L. arcana Hannaford Ellis, 1978 are well suited for microevolutionary studies, being at the same time closely related and intraspecifically diverse. The divergence between these two sibling species, sympatric over large parts of their distribution areas, is small, the only morphological difference being the pallial gland complex structure in females. Molecular identification is possible with the use of a RAPD nuclear marker (cloned A2.8 DNA fragment) typical for L. arcana. However, in some individuals from sympatric populations molecular and morphological criteria suggest conflicting species affiliation, which may be explained either by hybridization or by shared ancestral polymorphism. We tested the hybridization hypotheses examining the micro-spatial distribution of these two species across the intertidal zone in two distant sites at the Barents Sea. We found that (a) the frequency of putative hybrids in sympatric populations was proportional to the frequency of L. arcana; (b) L. saxatilis bearing A2.8 DNA fragment were almost absent in the lower part of the intertidal zone, where L. arcana was absent too; (c) there was a close positive correlation between the distribution of potential parent molluscs and putative hybrids. Moreover, logistic regression models showed a good agreement between the distribution of putative hybrid frequencies and that of parental species frequencies. All our observations taken together support the hypothesis of hybridization between L. saxatilis and L. arcana. Elucidating the mechanisms that support the species status of these sympatric populations is necessary. PMID:23887893

Granovitch, Andrei I; Maximovich, Alexei N; Avanesyan, Alina V; Starunova, Zinaida I; Mikhailova, Natalia A

2013-09-01

69

Barnacles, limpets and periwinkles: the effects of direct and indirect interactions on cyprid settlement and success  

NASA Astrophysics Data System (ADS)

Conventionally, direct interactions between species are considered to be the most important biological factors determining community composition, structure and stability. However, it has been suggested that the indirect interactions occurring between species may be as important. One area of ecology where the direct effects of one species on another have been well studied is in the rocky intertidal. Examination of the effect of the presence of P. vulgata (limpets) and L. littorea (periwinkles) on the settlement and development of S. balanoides (cyprids/barnacles), over a cyprid settlement season and some six months later, in four different treatments (limpets only, limpets and periwinkles combined, periwinkles only and control (no animals)) revealed the following: (1) that the presence of limpets increased cyprid settlement and recruitment success above treatments containing no limpets; (2) that cyprid settlement and success were greatest on the limpets-only treatment, followed by the limpets-and-periwinkles treatment, then by the control treatment and then by the periwinkles-only treatment; (3) that the initial effects observed in the treatments were reflected in the long-term community structure; (4) that the effects of the treatments were independent of variations in algal biomass between treatments, i.e. the effects were not indirectly mediated through a second species (host); (5) that cyprid mortality was greatest on the periwinkles-only treatment; (6) that the source of the effect of limpets on cyprid settlement appeared to originate indirectly through the action of their residual pedal mucus trails. It is concluded that periwinkles can affect the settlement and success of barnacles directly through biological disturbance (i.e. surface ablation). However, although limpets may have a direct negative effect on barnacle settlement and success, at low to medium densities, limpets can positively indirectly influence the cyprid settlement and success. This effect operates at a factor greater than that afforded by the direct negative effects of periwinkles in a mixed-species treatment. These results illustrate how the indirect effects of one species on another can have a more important structuring effect than those derived from direct effects alone.

Holmes, Sebastian P.; Walker, Graham; van der Meer, Jaap

2005-02-01

70

Madagascar basalts: tracking oceanic and continental sources  

Microsoft Academic Search

Extensive Upper Cretaceous volcanism in southern Madagascar was fed in part by mantle sources resembling those expressed today in the Indian Ocean at Marion and Prince Edward islands and on the central Southwest Indian Ridge. In addition, very low ?Nd(T) (to -17.4), high (87Sr\\/86Sr)T (to 0.72126) tholeiites in southwestern Madagascar were variably but highly contaminated by ancient continental material broadly

J. Mahoney; C. Nicollet; C. Dupuy

1991-01-01

71

Provenance and tectonic significance of the Palaeoproterozoic metasedimentary successions of central and nothern Madagascar  

USGS Publications Warehouse

New detrital zircon U–Pb age data obtained from various quartzite units of three spatially separated supracrustal packages in central and northern Madagascar, show that these units were deposited between 1.8 and 0.8 Ga and have similar aged provenances. The distribution of detrital zircon ages indicates an overwhelming contribution of sources with ages between 2.5 and 1.8 Ga. Possible source rocks with an age of 2.5 Ga are present in abundance in the crustal segments (Antananarivo, Antongil and Masora Domains) either side of a purported Neoproterozoic suture ("Betsimisaraka Suture Zone"). Recently, possible source rocks for the 1.8 Ga age peak have been recognised in southern Madagascar. All three supracrustal successions, as well as the Archaean blocks onto which they were emplaced, are intruded by mid-Neoproterozoic magmatic suites placing a minimum age on their deposition. The similarities in detrital pattern, maximum and minimum age of deposition in the three successions, lend some support to a model in which all of Madagascar's Archaean blocks form a coherent crustal entity (the Greater Dharwar Craton), rather than an amalgamate of disparate crustal blocks brought together only during Neoproterozoic convergence. However, potential source terranes exist outside Madagascar and on either side of the Neoproterozoic sutures, so that a model including a Neoproterozoic suture in Madagascar cannot be dispelled outright.

De Waele, B.; Thomas, Ronald J.; Macey, P.H.; Horstwood, M.S.A.; Tucker, R.D.; Pitfield, P.E.J.; Schofield, D.I.; Goodenough, K.M.; Bauer, W.; Key, R.M.; Potter, C.J.; Armstrong, R.A.; Miller, J.A.; Randriamananjara, T.; Ralison, V.; Rafahatelo, J.-M.; Rabarimanana, M.; Bejoma, M.

2011-01-01

72

The odd man out in Sub-Saharan Africa: understanding the tobacco use prevalence in Madagascar  

PubMed Central

Background The tobacco industry has globalized and tobacco use continues to increase in low- and middle-income countries. Yet, the data and research to inform policy initiatives for addressing this phenomenon is sparse. This study aims to estimate the prevalence of adult tobacco use in 17 Sub-Saharan Africa (SSA) countries, and to identify key factors associated with adult tobacco consumption choices (smoked, smokeless tobacco and dual use) in Madagascar. Methods We used Demographic Health Survey for estimating tobacco use prevalence among adults in SSA. A multinomial logistic regression model was used to identify key determinants of adult tobacco consumption choices in Madagascar. Results While differences in tobacco use exist in SSA, Madagascar has exceptionally higher prevalence rates (48.9% of males; 10.3% of females). The regression analyses showed complexity of tobacco use in Madagascar and identified age, education, wealth, employment, marriage, religion and place of residence as factors significantly associated with the choice of tobacco use among males, while age, wealth, and employment were significantly associated with that of females. The effects, however, differ across the three choices of tobacco use compared to non-use. Conclusions Tobacco use in Madagascar was higher than the other 16 SSA countries. Although the government continues to enact policies to address the problem, there is a need for effective implementation and enforcement. There is also the need for health education to modify social norms and denormalize tobacco use. PMID:24044737

2013-01-01

73

A Preliminary Investigation of Heavy Metals in Periwinkles from Warri River, Nigeria  

Microsoft Academic Search

Periwinkles samples (Tympanostomus fuscatus) bought from different major markets in Warri Township were investigated for elemental contaminants. The total levels of iron, copper, barium, lead, cadmium, chromium, nickel and cobalt were determined by atomic absorption spectrophotometry. All the metals except Cr ands Co were present in appreciable quantities in the samples. In descending order of predominance, the overall mean levels

J. G. Ayenimo; C. E. Adeeyinwo; I. A. Amoo; F. B. Odukudu

2005-01-01

74

Adsorption of methylene blue onto activated carbon derived from periwinkle shells: kinetics and equilibrium studies  

Microsoft Academic Search

Periwinkle shell, an abundant and inexpensive natural resource, was used to prepare activated carbon by physicochemical activation with potassium hydroxide (KOH) and carbon dioxide (CO2) as the activating agents at 850 °C for 2 h. The adsorption equilibrium and kinetics of methylene blue dye on such carbon were then examined at 25 °C. Adsorption isotherm of the methylene blue (MB) on the

Olugbenga Solomon Bello; Idowu Abideen Adeogun; John Chijioke Ajaelu; Ezekiel Oluwaseun Fehintola

2008-01-01

75

Stimulated Biodegradation of Crude Oil in Soil Amended with Periwinkle Shells  

Microsoft Academic Search

The potential of periwinkle shell (PS) in enhancing the microbial break down of crude oil spilled in soil were studied. The results revealed that the counts of crude oil degrading bacteria in oil-polluted soil fortified with PS were higher than the counts in unfortified soil. The rates and total extent of crude oil biodegradation in the soil were stimulated by

U. J. J. Ijah; M. Ndana

2003-01-01

76

An anomalous form of mycoplasma-like bodies in periwinkle infected with the sandal spike agent  

Microsoft Academic Search

An anomalous form of mycoplasma-like bodies was found in ‘necrotic’ cells in the sieve elements of periwinkle stem after infection with the sandal spike disease agent. These bodies, 50–160 nm in diameter, were strongly osmiophilic and bounded by a unit membrane. It is suggested that these anomalous bodies represent a naturally degenerated form of the mycoplasma-like bodies.

C. Hiruki; Jeanne Dijkstra

1973-01-01

77

Observations on the tidal activity rhythm of the periwinkle Littorina nigrolineata (Gray)  

Microsoft Academic Search

The spontaneous activity pattern of the periwinkle L. nigrolineata has been studied by direct observation in the field and under controlled conditions in the laboratory. In the laboratory the animals are induced to crawl by both immersion and exposure under simulated tidal conditions, and the increased activity following emersion has been confirmed by field observations. Animals kept submerged under constant

Saran Petpiroon; Elfed Morgan

1983-01-01

78

Heavy metal accumulation in the periwinkle Littorina littorea, along a pollution gradient in the Scheldt estuary  

Microsoft Academic Search

Inductively coupled plasma atomic emission spectrophotometry (ICP-AES) was used to determine heavy metal concentrations in the shells and soft tissues of the periwinkle Littorina littorea, collected at seven sites along the Scheldt estuary. Several metals accumulate in the animals soft body parts, and are related to the seawards decreasing pollution gradient. No clear correlation with a previously detected shell size

H De Wolf; T Backeljau; R Blust

2000-01-01

79

Mitochondrial DNA CoI haplotype variation in sibling species of rough periwinkles  

Microsoft Academic Search

Three sibling species of rough periwinkles are currently recognized: Littorina arcana, L. compressa and L. saxatilis. Certain forms of L. saxatilis are also argued by some to deserve species status, such as the barnacle-dwelling ‘L. neglecta’ and the lagoonal ‘L. tenebrosa’. Relationships between these taxa, and between and within representative populations, are investigated using sequence analysis and restriction fragment length

C S Wilding; J Grahame; P J Mill

2000-01-01

80

Biochemical Differences Between Trail Mucus and Adhesive Mucus From Marsh Periwinkle Snails  

Microsoft Academic Search

The composition of the adhesive form of marsh periwinkle mucus was compared to the trail mucus used during locomotion. The trail mucus consists primarily of large, carbohydrate-rich molecules with some relatively small proteins. In contrast, the adhesive mucus has 2.7 times as much protein with no significant difference in carbohy- drate concentration. The resulting gel has roughly equal amounts of

ANDREW M. SMITH; MARTHA C. MORIN

2002-01-01

81

Adaptive and non-adaptive variation in two species of rough periwinkle (Littorina) on British shores  

Microsoft Academic Search

Rough periwinkles are notoriously variable in shell characters. There are many reports of substantial local variation on single shores which not only make identification difficult but also may be difficult to understand in terms of likely selective pressures. We show that despite local variation in southern Britain there is evidence of a broader scale of change which is likely to

J. Grahame; P. J. Mill; A. C. Brown

1990-01-01

82

TWO NEW EIMERIANS (APICOMPLEXA) FROM INSECTIVOROUS MAMMALS IN MADAGASCAR  

E-print Network

TWO NEW EIMERIANS (APICOMPLEXA) FROM INSECTIVOROUS MAMMALS IN MADAGASCAR Lee Couch, Juha Laakkonen The Journal of #12;#12;TWO NEW EIMERIANS (APICOMPLEXA) FROM INSECTIVOROUS MAMMALS IN MADAGASCAR Lee Couch insectivorous mammals in Madagascar were collected between spring 1999 and fall 2001. In the Afrosoricida, 21

Jernvall, Jukka

83

Status of the Madagascar Fish Eagle Haliaeetus vociferoides in 1995  

Microsoft Academic Search

Rabarisoa, R., Watson, R.T., Thorstrom, R., & Berkelman, J. 1997. Status of the Madagascar Fish Eagle Haliaeetus vociferoides in 1995. Ostrich 68 (1): 8–12.Surveys for the Madagascar Fish Eagle Haliaeetus vociferoides were conducted each breeding season (May through October) from 1991 through 1995 between Morondava and Antsiranana, western to northwestern Madagascar, to estimate the population size of this endangered species.

Rivo Rabarisoa; Richard T. Watson; Russell Thorstrom; James Berkelman

1997-01-01

84

Pneumonic plague outbreak, Northern Madagascar, 2011.  

PubMed

Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Madagascar-specific 1.ORI3-k single-nucleotide polymorphism genotype and 4 clustered regularly interspaced short palindromic repeat patterns. This outbreak had a case-fatality rate of 100% for nontreated patients. The Y. pestis 1.ORI3-k single-nucleotide polymorphism genotype might cause larger epidemics. Multidrug-resistant strains and persistence of the pathogen in natural foci near human settlements pose severe risks to populations in plague-endemic regions and require outbreak response strategies. PMID:25530466

Richard, Vincent; Riehm, Julia M; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Scholz, Holger C; Rajerison, Minoarisoa

2015-01-01

85

Pneumonic Plague Outbreak, Northern Madagascar, 2011  

PubMed Central

Yersinia pestis, the causative agent of plague, is endemic to Madagascar, particularly to the central highlands. Although plague has not been previously reported in northern Madagascar, an outbreak of pneumonic plague occurred in this remote area in 2011. Over a 27-day period, 17 suspected, 2 presumptive, and 3 confirmed human cases were identified, and all 15 untreated 20 patients died. Molecular typing of Y. pestis isolated from 2 survivors and 5 Rattus rattus rat samples identified the Madagascar-specific 1.ORI3-k single-nucleotide polymorphism genotype and 4 clustered regularly interspaced short palindromic repeat patterns. This outbreak had a case-fatality rate of 100% for nontreated patients. The Y. pestis 1.ORI3-k single-nucleotide polymorphism genotype might cause larger epidemics. Multidrug-resistant strains and persistence of the pathogen in natural foci near human settlements pose severe risks to populations in plague-endemic regions and require outbreak response strategies. PMID:25530466

Richard, Vincent; Herindrainy, Perlinot; Soanandrasana, Rahelinirina; Ratsitoharina, Maherisoa; Rakotomanana, Fanjasoa; Andrianalimanana, Samuel; Scholz, Holger C.; Rajerison, Minoarisoa

2015-01-01

86

Receiver function analysis and preliminary body wave tomography of the MACOMO network in Madagascar  

NASA Astrophysics Data System (ADS)

We present results from a set of seismological studies of the continental island of Madagascar using new seismic data from the NSF-funded MACOMO (MAdagascar, COmores, and MOzambique) IRIS PASSCAL broadband seismometer array. MACOMO involved the deployment during 2011-2013 of 26 broadband seismometers in Madagascar and 6 seismometers in Mozambique, providing the first seismic imaging across the world's 4th-largest island. We present preliminary crustal structure variations from receiver function analyses and body wave tomography results. We calculate radial receiver functions for all Madagascar stations and use the weighted linear regression methodology of Herrmann and Ammon [2002] to invert for shear velocity. Upper mantle and crustal structures from the receiver function analyses are used to help determine starting models for the teleseismic travel-time tomography. The tectonic structure of Madagascar is generally divided into four crustal blocks. Initial seismic imaging shows that the Archean Antongil block that runs along the east of the island has the thickest crust (>40 km) and three Proterozoic terranes that make up the central highlands and are bounded by fault and shear zones are closer to the average crustal thickness (35 km). There has been late Cenozoic intraplate volcanism in northern and central Madagascar (as recently as 1 million years ago), and different hypotheses for its origin will be evaluated by the preliminary results from the three different seismic studies. Complete analyses will be done incorporating seismic data from simultaneous and complementary array of both land- and ocean-based seismometers from French and German deployments.

Pratt, M. J.; Wysession, M. E.; Wiens, D. A.; Nyblade, A.; Aleqabi, G. I.; Shore, P.; Rambolamana, G.; Sy Tanjona Andriampenomanana ny Ony, F.; Rakotondraibe, T.

2013-12-01

87

Geological evolution of the Neoproterozoic Bemarivo Belt, northern Madagascar  

USGS Publications Warehouse

The broadly east-west trending, Late Neoproterozoic Bemarivo Belt in northern Madagascar has been re-surveyed at 1:100 000 scale as part of a large multi-disciplinary World Bank-sponsored project. The work included acquisition of 14 U-Pb zircon dates and whole-rock major and trace element geochemical data of representative rocks. The belt has previously been modelled as a juvenile Neoproterozoic arc and our findings broadly support that model. The integrated datasets indicate that the Bemarivo Belt is separated by a major ductile shear zone into northern and southern "terranes", each with different lithostratigraphy and ages. However, both formed as Neoproterozoic arc/marginal basin assemblages that were translated southwards over the north-south trending domains of "cratonic" Madagascar, during the main collisional phase of the East African Orogeny at ca. 540 Ma. The older, southern terrane consists of a sequence of high-grade paragneisses (Sahantaha Group), which were derived from a Palaeoproterozoic source and formed a marginal sequence to the Archaean cratons to the south. These rocks are intruded by an extensive suite of arc-generated metamorphosed plutonic rocks, known as the Antsirabe Nord Suite. Four samples from this suite yielded U-Pb SHRIMP ages at ca. 750 Ma. The northern terrane consists of three groups of metamorphosed supracrustal rocks, including a possible Archaean sequence (Betsiaka Group: maximum depositional age approximately 2477 Ma) and two volcano-sedimentary sequences (high-grade Milanoa Group: maximum depositional age approximately 750 Ma; low grade Daraina Group: extrusive age = 720-740 Ma). These supracrustal rocks are intruded by another suite of arc-generated metamorphosed plutonic rocks, known as the Manambato Suite, 4 samples of which gave U-Pb SHRIMP ages between 705 and 718 Ma. Whole-rock geochemical data confirm the calc-alkaline, arc-related nature of the plutonic rocks. The volcanic rocks of the Daraina and Milanoa groups also show characteristics of arc-related magmatism, but include both calc-alkaline and tholeiitic compositions. It is not certain when the two Bemarivo terranes were juxtaposed, but ages from metamorphic rims on zircon suggest that both the northern and southern terranes were accreted to the northern cratonic margin of Madagascar at about 540-530 Ma. Terrane accretion included the assembly of the Archaean Antongil and Antananarivo cratons and the high-grade Neoproterozoic Anaboriana Belt. Late- to post-tectonic granitoids of the Maevarano Suite, the youngest plutons of which gave ca. 520 Ma ages, intrude all terranes in northern Madagascar showing that terrane accretion was completed by this time. ?? 2009 Natural Environment Research Council (NERC).

Thomas, Ronald J.; De Waele, B.; Schofield, D.I.; Goodenough, K.M.; Horstwood, M.; Tucker, R.; Bauer, W.; Annells, R.; Howard, K. J.; Walsh, G.; Rabarimanana, M.; Rafahatelo, J.-M.; Ralison, A.V.; Randriamananjara, T.

2009-01-01

88

Earth structure and instrumental seismicity of Madagascar: Implications on the seismotectonics  

NASA Astrophysics Data System (ADS)

The aim of this study is to improve the knowledge of the seismotectonics of Madagascar. We first investigate the structure of the Earth beneath Madagascar through the joint inversion of receiver functions and Rayleigh wave group velocities. Then we use the obtained velocity models to relocate local earthquakes in order to analyse the distribution of seismicity. Finally, we use structural models and earthquake coordinates to compute focal mechanisms. Our retrieved Earth structure models confirm a thin lithosphere beneath Madagascar when compared to the nearby East African Rift. The High Plateau in the Central region coincides with the thinnest lithosphere over the slowest asthenosphere. Our results are in good agreement with the gravity anomalies and likely confirm a localised asthenospheric upwelling beneath the central part of Madagascar. The surface expression of the asthenospheric upwelling consists in a horst-graben structure. The moderate seismicity is localised along pre-existing structures reflecting an E-W extension that is mostly accommodated in the lower crust.

Rindraharisaona, Elisa Josiane; Guidarelli, Mariangela; Aoudia, Abdlkarim; Rambolamanana, Gérard

2013-05-01

89

The Ranotsara Zone in southern Madagascar - a \\  

Microsoft Academic Search

During amalgamation of Gondwana in Neoproterozoic to early Paleozoic times, the Precambrian basement of southern Madagascar was incorporated into the East African Orogen (EAO after Stern 1994) and deformed at high-grade metamorphic conditions. Before breakup of Gondwana, its general position is thought to be in between eastern Africa and India. Very often tight-fit Gondwana reconstructions are based on similarities of

Giese Jörg; Schreurs Guido; Berger Alfons; Gnos Edwin

90

New Primates Discovered in Madagascar and Brazil  

NSDL National Science Digital Library

Nine lemur and two marmoset species native to the forests of Madagascar and Brazil, and new to (Western) science, were described earlier this month. Despite the excitement associated with this discovery, the forest habitats of most of these species appear to be already at risk from development pressures. This news brief from Environment News Service gives an overview of the discovery.

Lazaroff, Cat

2001-01-01

91

Purification and characterization of a copper-binding protein from Asian periwinkle Littorina brevicula  

Microsoft Academic Search

The Asian periwinkle, Littorina brevicula, is highly resistant to a wide range of heavy metal concentrations and its metal-binding protein(s) are induced in the presence of cadmium (Cd) and zinc (Zn). In this study, we isolated and characterized a novel copper-binding protein (Cu-BP). Following purification by Sephacryl S-100 chromatography, Cu-BP contained an equal amount of Zn in non-exposed physiological conditions.

Soo-Kyung Ryu; Jin-Sung Park; In-Sook Lee

2003-01-01

92

Microgeographical variation in shell strength in the flat periwinkles Littorina obtusata and Littorina mariae  

Microsoft Academic Search

The strength of molluscan shells has been shown to vary in adaptive ways in a number of species and one of the main factors\\u000a thought to be involved is shell-crushing by predators. A recent study found that the sibling species of flat periwinkle Littorina obtusata and Littorina mariae showed significant differences in the rates at which shell strength increased with

C. R. Fletcher

1995-01-01

93

Palatability and Chemical Defense of Phragmites australis to the Marsh Periwinkle Snail Littoraria irrorata  

Microsoft Academic Search

Coastal marsh habitats are impacted by many disturbances, including habitat destruction, pollution, and the introduction of\\u000a invasive species. The common reed, Phragmites australis, has been particularly invasive in the mesohaline regions of the Chesapeake Bay, but few studies have investigated its role\\u000a in trophic interactions with North American marsh consumers. The marsh periwinkle snail Littoraria irrorata is a common grazer

Lindsey G. Hendricks; Hannah E. Mossop; Cynthia E. Kicklighter

2011-01-01

94

EFFECT OF NON - MONETARY INPUTS ON THE YIEDLING PERFORMANCE OF PERIWINKLE (Catharanthus sp.).  

PubMed

An experiment to study the effect of inter and intra row spacing on the yielding performance of periwinkle species was conducted at Nagarjun Medicinal and Aromatic Plants Research Scheme, P. K. V., Akola (M. S.) during 1980 - 81 to 82 - 83. Three species viz., Catharanthus roseus, Catharanthus alba and Catharanthus oscillatus did not differ significantly in respect of dried foliage and root yields. Inter and intra row spacing of 30 and 20 cm. respectively produced the highest foliage and root yields. PMID:22557502

Dahatonde, B N

1985-07-01

95

Grazing on green algae by the periwinkle Littorina littorea in the Wadden Sea  

Microsoft Academic Search

On sedimentary tidal flats in the Wadden Sea near the Island of Sylt, the periwinkleLittorina littorea occurred preferentially on clusters and beds of mussels and on shell beds (100 to 350 m?2), achieved moderate densities on green algal patches or mats (20 to 50 m?2), and remained rare on bare sediments (?2). Green algae covering>10% of sediment surface appeared in

U. Wilhelmsen; K. Reise

1994-01-01

96

COMPETITIVE DISPLACEMENT OF NATIVE MUD SNAILS BY INTRODUCED PERIWINKLES IN THE NEW ENGLAND INTERTIDAL ZONE  

Microsoft Academic Search

During the nineteenth century the mud snail Ilyanassa obsoleta was abundant on sand and mud flats,wood works,sea walls, salt marshes,eel grassbeds, and cobble beaches in New England. With the exception of sand and mud flats, these habitats arenowlargely occupied bytheintroduced periwinkle, Littorina littorea. Todetermine whetherLittorina competitively displaces Ilyanassa, anexperimental studywascon ducted at a site in BarnstableHarbor,Massachusettswherethe observeddistributions overlapped by3% byMonsita's

G. A. BRENCHLEY; J. T. CARLTON

97

A geographically-based study of shell shape in small rough periwinkles  

Microsoft Academic Search

A study using principal component analysis and discriminant analysis was carried out on shell shape variation in 3093 specimens\\u000a of rough periwinkles, 2500 of which were below 5.5 mm in columella length, from around the North Atlantic. Using a combination\\u000a of colour plus sculpture, and life history trait, the snails were classified by inspection and examination into Littorina nigrolineata, L.

K. J. Caley; J. Grahame; Peter J. Mill

1995-01-01

98

Uptake and depuration of 131I by the edible periwinkle Littorina littorea: uptake from seawater  

Microsoft Academic Search

Uptake and depuration experiments for the edible periwinkle Littorina littorea have been performed using 131I-labelled seawater. Throughout the experimental phase the winkles were fed on unlabelled Chondrus crispus. 131I concentrations in winkles during uptake followed linear first-order kinetics with an uptake half-time of 11 days, whereas for depuration a triphasic sequence with biological half-lives of 4, 23 and 56 days

J. Vives i Batlle; R. C. Wilson; P. McDonald; T. G. Parker

2004-01-01

99

Dispersion of the salt-marsh periwinkle Littoraria irrorata : Effects of water level, size, and season  

Microsoft Academic Search

This paper documents horizontal and vertical dispersion patterns of a Texas population of the saltmarsh periwinkle, Littoraria irrorata, over a 15-month period. The study was conducted within a tidal marsh on the Anahuac National Wildlife Refuge in Galveston\\u000a Bay. Two mark-recapture experiments demonstrated that L. irrorata rarely move more than 2 m from their release point over long periods of

Caryn C. Vaughn; Frank M. Fisher

1992-01-01

100

Chemical Composition and Pharmacological Activity of Alkaloids from the Common Periwinkle Cultured in Georgia  

Microsoft Academic Search

periwinkle to the field of the Experimental Center of Medicinal Plants (Shiraki, East Kakhetia) was successful, leading to an increase in the alkaloid content. The total alkaloid yield reached up to 1 and 0.8%, in which the vincamine content amounted to 0.06 and 0.04%, in the blooming and fruitage stages, respectively. The purpose of this study was to refine the

V. Yu. Vachnadze; É. Z. Dzhakeli; Z. V. Robakidze; G. V. Chkhikvadze; M. M. Mudzhiri; G. V. Abuladze; N. A. Chuchulashvili

2001-01-01

101

This composite image reveals the typical habitat for the periwinkle snail which colonises the tidal splash zone of the upper rock wall, where the grey rock surface is blackened by biofilm  

E-print Network

This composite image reveals the typical habitat for the periwinkle snail which colonises the tidal Doncaster's team is investigating responses by rocky-shore periwinkle snails to the depletion is applying this concept to the slow moving ­ and thus easily examined ­ periwinkle snail Melaraphe neritoides

Anderson, Jim

102

Low-temperature evolution of the Morondava rift shoulder in western Madagascar  

NASA Astrophysics Data System (ADS)

Separation of Madagascar from eastern Africa resulted in the development of sedimentary basins covering the west coast of Madagascar. The largest and oldest of these basins, the Morondava basin, is bound to the east by crystalline basement of Precambrian age and stretches into the Mozambique Channel to the west. The evolution of the sedimentary sequence is mainly influenced by (I) a Permo-Triassic continental failed rift (e.g. Clark, 1998), also referred to as the Karroo rift (e.g., Montenat et al., 1996) and (II) the early Jurassic separation of Madagascar from eastern Africa (Geiger et al., 2004). Deposits related to the Karroo rift are restricted to a narrow corridor along the basement-basin contact. The rift locus shifted to the west before final separation and relative southward displacement of Madagascar commenced in early Jurassic times (Geiger et al., 2004). In the central part of the basin, the basement-basin contact features a steep escarpment with an altitude difference of greater than 1000 m from the sedimentary plains to the crystalline basement. Here, apatite fission-track analysis of a series of both basement and sediment samples across the escarpment provides the possibility to study the low temperature evolution of the exhuming Precambrian basement in the rift basin shoulder and the associated thermal evolution of the sedimentary succession. The timing of basement surface exposure is constrained by the stratigraphic ages of the overlying sediments and modelling of the thermal evolution indicates post-depositional thermal overprinting of basement and Karroo age sediments with partial annealing of fission tracks related to burial by Mesozoic sediments. The temperatures of this heating / reheating of the basin shoulder increase towards the west in the presently exposed sequences. The westernmost sample experienced almost complete resetting of the detrital apatite grains. The general younging of the apparent apatite fission-track ages towards the west indicates activity of faults, re-activating inherited Precambrian structures along the present basin-basement contact during Karroo sedimentation. Furthermore, our data show that onset of final exhumation can be correlated with (I) the end of Madagascar's drift southward relative to Africa along the Davie Ridge in the Mozambique Channel during the Early Cretaceous (Coffin and Rabinowitz, 1988), (II) activity of the Marion hot spot beneath southern Madagascar and associated Late Cretaceous break-up between Madagascar and India (Storey et al., 1995), and (III) the collision of India with Eurasia and subsequent re-organization of transform faults and spreading ridges. References Clark, D.N. (1998): Review of the exploration potential of Madagascar. Houston Geological Society Bulletin, p. 23-29. Coffin, M.F. and Rabinowitz, P.D. (1988): Evolution of the conjugate east African-Madagascan Margins and the western Somali basins. GSA Special Paper 226, pp. 78. Geiger, M., Clark, D.N. and Mette, W. (2004): Reappraisal of the timing of the breakup of Gondwana based on sedimentological and seismic evidence from the Morondava Basin, Madagascar. Journal of African Earth Sciences, v. 38, p. 363-381. Montenat, C., Ramahavory, L. and Croisile, M. (1996): Tectonic and sedimentary evolution of the Western Madagascan margin during the Jurassic in the Morondava basin, Madagascar. Bulletin des centres de recherches Exploration-Production Elf Aquitaine, v. 20, p. 323-340. Storey, M., Mahoney, J.J., Saunders, A.D., Duncan, R.A., Kelley, S.P. and Coffin, M.F. (1995): Timing of hot spot-related volcanism and the break-up of Madagascar and India. Science, v. 267, p. 852-855.

Giese, Jörg; Seward, Diane; Schreurs, Guido

2010-05-01

103

AMS 14C Dates for Extinct Lemurs from Caves in the Ankarana Massif, Northern Madagascar  

NASA Astrophysics Data System (ADS)

An extensive late Quaternary fauna, including many extinct giant lemurs, has been collected recently in a 110+-km system of caves in the Ankarana Massif of northern Madagascar. AMS 14C dates for the acid-insoluble (collagen/gelatin) fraction of bones of the giant lemur Megaladapis (26,150 ± 400 and 12,760 ± 70 yr B.P.) confirm its presence in the area during the late Pleistocene and provide the first Pleistocene 14 C ages from bones of the extinct megafauna of the island. The first date from bones of the recently described extinct Babakotia radofilai (4400 ± 60 yr B.P.) shows that it was present in northern Madagascar in mid-Holocene times. A comparatively recent age of 1020 ± 50 yr B.P. for the extinct Archaeolemur indicates survival of this genus for at least a millennium after the first direct evidence for humans in Madagascar. This suggests that the island's "extinction window" may have represented a longer time span than would have been expected under the Blitzkrieg model of late Quaternary extinctions. A mid-Holocene age (4560 ± 70 yr B.P.) for a bone sample of the small extant lemur Hapalemur simus indicates that the disappearance of this now-restricted species from the Ankarana occurred after this date. New data from the Ankarana and other sites on the island add to the consensus that major biotic changes occurred on Madagascar in the late Holocene.

Simons, Elwyn L.; Burney, David A.; Chatrath, Prithijit S.; Godfrey, Laurie R.; Jungers, William L.; Rakotosamimanana, Berthe

1995-03-01

104

Vicious circle in the intertidal: Facilitation between barnacle epibionts, a shell boring polychaete and trematode parasites in the periwinkle Littorina littorea  

Microsoft Academic Search

We studied interactions between three organisms associated with a common gastropod of northern Atlantic shores, the periwinkle Littorina littorea: barnacle epibionts Balanus crenatus, a shell boring polychaete Polydora ciliata, and tissue invading trematodes which use the periwinkles as first intermediate host. Snails collected shortly after barnacle settlement with >50% cover of barnacles had significantly higher infestation of shell boring worms

David W. Thieltges; Christian Buschbaum

2007-01-01

105

Rifting between India and Madagascar - mechanism and isostasy  

NASA Astrophysics Data System (ADS)

The nature of isostasy along the Western Continental Margin of India (WCMI) and the Eastern Continental Margin of Madagascar (ECMM) and their conjugate nature are examined. The first part of the study deals with the estimation of effective elastic thickness ( Te) of the lithosphere for the two margins through cross-spectral analysis of gravity and bathymetry data. The results bring out comparable Te values of 8-15 km for the WCMI and 10-13 km for the ECMM, despite the WCMI having been traversed along strike by a hotspot trace. We have also compared topographic profiles across the two margins extending inland, to examine the rift-flank uplift experienced by the two landmasses abutting the margins, which bear a striking similarity. These results establish the symmetrical rifting mechanism resulting in the formation of the two margins, and indicate that despite the presence of a hotspot trace along one margin (i.e. the WCMI), the two margins have comparable isostatic compensation mechanisms with low Te values. In the second part of the study we have examined the possible mechanism for the rift-flank uplifts using a process-oriented approach of backstripping the sediments along a traverse across the WCMI and reconstructing the original rift flank topography by flexurally backstacking the amount of eroded material on the present-day topography of the Western Ghats. The backstack load configuration is taken from the amount of erosion that took place over the Western Ghats, obtained from AFTA (Apatite Fission Track Analysis) studies. The reconstructed rift time topography and bathymetry are used to get the Moho configuration, which was used to calculate the gravity anomaly, and is compared with the observed anomaly to derive a possible evolution model for the region. We have tried to examine the observed gravity anomaly through two different processes. In the first process, a Te=15 km for backstripping and backstacking, and a compensated underplating for the topography give a best fit model to the observed gravity. In the second process, a necking model with a deep level of necking (20 km) with Te=15 km and without any underplating explains the topography as well as the observed gravity. The nature and amount of the Western Ghat topography and cratonic age (Archaen) of the pre-rifted crust of western India and eastern Madagascar are more in favor of the rifting mechanism (necking model) rather than due to the passage of the Reunion hotspot (underplating model). This is evidenced by the observed increase in topography away from the influence of the Reunion hotspot trace as well as the presence of a similar topography in Madagascar.

Chand, Shyam; Subrahmanyam, C.

2003-05-01

106

A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar  

PubMed Central

Background Current models propose that mitochondrial DNA macrohaplogroups M and N evolved from haplogroup L3 soon after modern humans left Africa. Increasingly, however, analysis of isolated populations is filling in the details of, and in some cases challenging, aspects of this general model. Results Here, we present the first comprehensive study of three such isolated populations from Madagascar: the Mikea hunter-gatherers, the neighbouring Vezo fishermen, and the Merina central highlanders (n = 266). Complete mitochondrial DNA genome sequences reveal several unresolved lineages, and a new, deep branch of the out-of-Africa founder clade M has been identified. This new haplogroup, M23, has a limited global distribution, and is restricted to Madagascar and a limited range of African and Southwest Asian groups. Conclusions The geographic distribution, phylogenetic placement and molecular age of M23 suggest that the colonization of Madagascar was more complex than previously thought. PMID:20003445

2009-01-01

107

Agro-environmental determinants of avian influenza circulation: a multisite study in Thailand, Vietnam and Madagascar.  

PubMed

Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 2004-2005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced. PMID:25029441

Paul, Mathilde C; Gilbert, Marius; Desvaux, Stéphanie; Andriamanivo, Harena Rasamoelina; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Véronique

2014-01-01

108

Agro-Environmental Determinants of Avian Influenza Circulation: A Multisite Study in Thailand, Vietnam and Madagascar  

PubMed Central

Outbreaks of highly pathogenic avian influenza have occurred and have been studied in a variety of ecological systems. However, differences in the spatial resolution, geographical extent, units of analysis and risk factors examined in these studies prevent their quantitative comparison. This study aimed to develop a high-resolution, comparative study of a common set of agro-environmental determinants of avian influenza viruses (AIV) in domestic poultry in four different environments: (1) lower-Northern Thailand, where H5N1 circulated in 2004–2005, (2) the Red River Delta in Vietnam, where H5N1 is circulating widely, (3) the Vietnam highlands, where sporadic H5N1 outbreaks have occurred, and (4) the Lake Alaotra region in Madagascar, which features remarkable similarities with Asian agro-ecosystems and where low pathogenic avian influenza viruses have been found. We analyzed H5N1 outbreak data in Thailand in parallel with serological data collected on the H5 subtype in Vietnam and on low pathogenic AIV in Madagascar. Several agro-environmental covariates were examined: poultry densities, landscape dominated by rice cultivation, proximity to a water body or major road, and human population density. Relationships between covariates and AIV circulation were explored using spatial generalized linear models. We found that AIV prevalence was negatively associated with distance to the closest water body in the Red River Delta, Vietnam highlands and Madagascar. We also found a positive association between AIV and duck density in the Vietnam highlands and Thailand, and with rice landscapes in Thailand and Madagascar. Our findings confirm the important role of wetlands-rice-ducks ecosystems in the epidemiology of AI in diverse settings. Variables influencing circulation of the H5 subtype in Southeast Asia played a similar role for low pathogenic AIV in Madagascar, indicating that this area may be at risk if a highly virulent strain is introduced. PMID:25029441

Paul, Mathilde C.; Gilbert, Marius; Desvaux, Stéphanie; Rasamoelina Andriamanivo, Harena; Peyre, Marisa; Khong, Nguyen Viet; Thanapongtharm, Weerapong; Chevalier, Véronique

2014-01-01

109

Development of Environmental Education Programs for Protected Areas in Madagascar  

ERIC Educational Resources Information Center

Environmental education programs for schools in the peripheral zone of protected areas in Madagascar are still needed in numerous locations. My research investigated the status of environmental education and communication (EE&C) programs at Masoala National Park, Madagascar, as well as the attitudes of local residents toward the park and park…

Ormsby, Alison

2007-01-01

110

A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar  

Microsoft Academic Search

BACKGROUND: Current models propose that mitochondrial DNA macrohaplogroups M and N evolved from haplogroup L3 soon after modern humans left Africa. Increasingly, however, analysis of isolated populations is filling in the details of, and in some cases challenging, aspects of this general model. RESULTS: Here, we present the first comprehensive study of three such isolated populations from Madagascar: the Mikea

François-X Ricaut; Harilanto Razafindrazaka; Murray P Cox; Jean-M Dugoujon; Evelyne Guitard; Clement Sambo; Maru Mormina; Marta Mirazon-Lahr; Bertrand Ludes; Eric Crubézy

2009-01-01

111

An Abelisauroid Theropod Dinosaur from the Turonian of Madagascar  

PubMed Central

Geophysical evidence strongly supports the complete isolation of India and Madagascar (Indo-Madagascar) by ?100 million years ago, though sparse terrestrial fossil records from these regions prior to ?70 million years ago have limited insights into their biogeographic history during the Cretaceous. A new theropod dinosaur, Dahalokely tokana, from Turonian-aged (?90 million years old) strata of northernmost Madagascar is represented by a partial axial column. Autapomorphies include a prominently convex prezygoepipophyseal lamina on cervical vertebrae and a divided infraprezygapophyseal fossa through the mid-dorsal region, among others. Phylogenetic analysis definitively recovers the species as an abelisauroid theropod and weakly as a noasaurid. Dahalokely is the only known dinosaur from the interval during which Indo-Madagascar likely existed as a distinct landmass, but more complete material is needed to evaluate whether or not it is more closely related to later abelisauroids of Indo-Madagascar or those known elsewhere in Gondwana. PMID:23637961

Farke, Andrew A.; Sertich, Joseph J. W.

2013-01-01

112

A Conservation Strategy for the Amphibians of Madagascar Une Stratgie de Conservation pour les Amphibiens de Madagascar  

E-print Network

1 A Conservation Strategy for the Amphibians of Madagascar Une Stratégie de Conservation pour les A conservation strategy for amphibians of Madagascar 08.30-09.00 Accueil des participants Welcome le Ministre The Minister La crise des amphibiens The amphibian crisis 09.30-09.50 Talk La

Andreone, Franco

113

Economie et enseignement a Madagascar. (Economy and Education in Madagascar.) Financement des systemes educatifs: etudes de cas Nationales 8.  

ERIC Educational Resources Information Center

The purpose of this volume is to analyze the problems of school finance in Madagascar, including those that have arisen in the past decade and those anticipated in the present decade (through 1980). More generally, this book examines past and future connections between the economic and educational systems in Madagascar. The author examines the…

Hugon, Philippe

114

Recent seawater temperature histories, status, and predictions for Madagascar’s coral reefs  

Microsoft Academic Search

Recent temperature histories and benthic surveys of Madagascar's coral reefs are pre- sented from 3 disparate regions in order to develop an understanding of the relationship between sea surface temperature (SST) and benthic cover, coral diversity, and community structure. Results indi- cate the presence of distinct temperature zones influenced by windward and seaward positions, lati- tude, intra- and inter-annual cycles,

Tim R. McClanahan; Mebrahtu Ateweberhan; Johnstone Omukoto; Louis Pearson

2009-01-01

115

[Epidemiological data on the plague in Madagascar].  

PubMed

The first case of plague was introduced in Madagascar in 1898 in the east coast by way of boat from India. In 1921, plague reach the highlands and a large epidemic over the next twenty years. Until the beginning of the 80's, only of few case were identified, notified mostly in rural setting. However gradually it has re-emerged as a public health problem. Urban plague is located in the city of Antananarivo (resurgence in 1978 after 28 years of apparent silence) and in Mahajanga port (resurgence in 1991 after 63 years of silence). The reactivation of the Plague National Control Program from 1994 will allow better surveillance. The aim of this analysis is to update the epidemiological data on human plague in Madagascar based on reported cases obtained from the Central Lab of the Pasteur Institute of Madagascar from 1980 to 2001 (16,928 suspected cases of which 3,500 are likely positives or confirmed positives). The Plague season runs from October to March on the central highlands and July to November on the north-western coast. Sex-ratio male/female is 1.3/1, and the age-group of 5 to 25 years is more affected. The case fatality rate was 40% in the beginning of the 1980's, and decreased to 20% by the end of the 1990's. The percentage of case with pulmonary plague decrease from 15% to less than 5%. However, geographical extension is demonstrated: 4 districts in 1980, 30 districts in 1999 and 21 districts in 2001. In 2002, the diffusion of a new rapid test (reagent strip) in the primary health centres (CSB) in 42 endemic districts may help to decrease the morbidity and the letality due to plague and improve its control at the national level. PMID:12643093

Ratsitorahina, M; Chanteau, S; Rosso, M L; Randriambelosoa, J; Ratsifasoamanana, L; Rabarijaona, L P; Mauclère, P; Migliani, R

2002-01-01

116

Electrophoretic heterogeneity within and between flat periwinkles (Mollusca: Gastropoda) along an intertidal transect at Ria Ferrol, northwest Spain  

Microsoft Academic Search

Using isoelectric focusing of esterases (EST), general proteins (GP) and myoglobin (Mb), we surveyed intra- and interspecific differentiation in flat periwinkles along a vertical intertidal transect in the Ensenada do Baño at Ria Ferrol, N.W. Spain. In this region, L. obtusata occurs in four algal belts, although it is rare in the lowest zone defined by Fucus serratus. L. fabalis

C. Olabarria; J.-M. Timmermans; T. Backeljau

1998-01-01

117

Increasing the content of leaf and root alkaloids of high alkaloid content mutants of periwinkle through nitrogen fertilization  

Microsoft Academic Search

In industrial plants such as medicinal plants, the content of the economically important metabolite is more important than the yield of the plant part containing the metabolite, as it determines the cost of extraction of the metabolite. Two high alkaloid content mutants of periwinkle (Catharanthus roseus, a medicinal plant yielding anti-cancer and anti-hypertension alkaloids) were developed through induced mutagenesis. Since

Y. Sreevalli; R. N. Kulkarni; K. Baskaran; R. S. Chandrashekara

2004-01-01

118

Effect of phytoplasmal infection on concentration and translocation of carbohydrates and amino acids in periwinkle and tobacco  

Microsoft Academic Search

Source and sink tissue of Catharanthus roseus (periwinkle) infected with the grapevine yellows (GY), apple proliferation (AP), or ash yellows (ASHY) phytoplasma and of Nicotiana tabacum (tobacco) infected with the AP phytoplasma, were examined for concentrations of glucose, fructose, sucrose, starch and total amino acids. Phytoplasmal infection caused growth inhibition and severe yellowing in both plants, the GY phytoplasma being

P LEPKA; M STITT; E MOLL; E SEEMÜLLER

1999-01-01

119

The effect of trail?following on the locomotion of the marsh periwinkle Littorina irrorata (mesogastropoda: Littorinidae)  

Microsoft Academic Search

The marsh periwinkle, Littorina irrorata, like many gastropods, can detect conspecific mucous trails and often follows them with polarity. Although trail?following is a common component of L. irrorata's behavioral repertoire, the adaptive significance of this behavior is not evident. This study examined some of the biomechanical and energetic advantages of tracking in L. irrorata.Mean crawling speeds of L. irrorata on

Richard A. Tankersley

1989-01-01

120

Integrated laboratory and field assessments of heavy metals accumulation in edible periwinkle, Tympanotonus fuscatus var radula (L.)  

Microsoft Academic Search

Laboratory and field bioaccumulation experiments were employed in assessing the impact of metal-laden effluents on the tissue concentrations of heavy metals in edible periwinkle, Tympanotonus fuscatus, in Lagos Lagoon. The field experiments showed that Zn and Pb accumulated in T. fuscatus collected from impacted stations were found to be about 10 times higher than the concentrations detected in control animals.

A. A Otitoloju; K. N Don-Pedro

2004-01-01

121

Periwinkle (Littorina littorea) as a sentinel species: a field study integrating chemical and biological analyses.  

PubMed

The gastropod Littorina littorea (common periwinkle) is an abundant and widespread North Atlantic species. The characteristic development of Intersex in L. littorea has been widely applied as a biomarker for tributyltin (TBT) contamination. Here, we assess the potential of L. littorea as a novel sentinel species for evaluating the sublethal effects in wild populations of widely distributed contaminants. We collected animals from six sites across the South coast of England. Tissue concentrations of polycyclic aromatic hydrocarbons (PAHs), organotin compounds (OTCs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were measured and compared with biomarkers of damage to DNA (Comet assay), lysosomal stability (NRR assay), and endocrine disruption (Intersex development). There was a strong correlation between DNA damage and PAH bioaccumulation (n=6, r=0.84, p<0.05), as well as that between Intersex development and OTC pollution (n=6, r=0.91, p<0.05). The relationship between PAH bioaccumulation and DNA strand breaks was nonlinear, highlighting the need to consider the role of adaptive mechanisms in the interpretation of field results. These results illustrate the potential use of periwinkles for monitoring a wide range of priority pollutants. PMID:21401085

Noventa, Seta; Pavoni, Bruno; Galloway, Tamara S

2011-04-01

122

Age-dependent zonation of the periwinkle Littorina littorea (L.) in the Wadden Sea  

NASA Astrophysics Data System (ADS)

On sedimentary tidal flats near the island of Sylt (German Bight, North Sea) abundance and size distribution of periwinkles, Littorina littorea L., were studied in low intertidal and in shallow and deep subtidal mussel beds ( Mytilus edulis L.). In low intertidal mussel beds, surveys revealed that high densities (1,369±571 m-2) of juvenile snails (?13 mm) were positively correlated with strong barnacle epigrowth ( Semibalanus balanoides L. and Balanus crenatus Bruguière) on mussels. A subsequent field experiment showed that recruitment of L. littorea was restricted to the intertidal zone. Abundances of periwinkles (213±114 m-2) and barnacles abruptly decreased in the adjacent shallow subtidal zone, which served as a habitat for older snails (>13 mm). L. littorea was completely absent from disjunct deep (5 m) subtidal mussel beds. Snail abundance varied seasonally with maxima of >4,000 m-2 in low intertidal mussel beds in October and minima in July, just before the onset of new recruitment. I suggest that the presence of cracks and crevices among the dense barnacle overgrowth in intertidal mussel beds favoured recruitment and survival of juvenile snails. Larger (older) specimens are assumed to actively migrate to the less favourable adjacent subtidal. Therefore, intertidal mussel beds are considered as nurseries for the population of L. littorea in the Wadden Sea.

Saier, Bettina

2000-12-01

123

Grazing on green algae by the periwinkle Littorina littorea in the Wadden Sea  

NASA Astrophysics Data System (ADS)

On sedimentary tidal flats in the Wadden Sea near the Island of Sylt, the periwinkle Littorina littorea occurred preferentially on clusters and beds of mussels and on shell beds (100 to 350 m-2), achieved moderate densities on green algal patches or mats (20 to 50 m-2), and remained rare on bare sediments (<5 m-2). Green algae covering>10% of sediment surface appeared in summer on approximately one third of the tidal zone, mainly in the upper and sheltered parts and almost never on mussel and shell beds. In feeding experiments, L. littorea ingested more of the dominant alge, Enteromorpha, than of Ulva, irrespective of whether or not algae were fresh or decaying. The tough thalli of Chaetomorpha were hardly consumed. Snails feeding on Enteromorpha produced fecal pellets from which new growth of Enteromorpha started. In the absence of periwinkles, Enteromorpha developed on mussels and the attached fucoids. Experimentally increased snail densities on sediments prevented green algal development, but the snails were unable to graze down established algal mats. It is concluded that natural densities of L. littorea hardly affect the ephemeral mass development of green algae on sediments. However, where the snails occur at high densities, i.e. on mussel beds, green algal development may be prevented.

Wilhelmsen, U.; Reise, K.

1994-06-01

124

The Madagascar Bloom: A serendipitous study  

NASA Astrophysics Data System (ADS)

The late austral summer (February-April) phytoplankton bloom that occurs east of Madagascar exhibits significant interannual variability and at its largest extent covers ~1% of the world's ocean surface area. The bloom raises many intriguing questions about how it begins, is sustained, propagates to the east, exports carbon, and ends. It has been observed and studied using satellite ocean color observations, but the lack of in situ data makes it difficult to address these questions. Here we describe observations that were made serendipitously on a cruise in February 2005. These show clearly for the first time the simultaneous existence of a deep chlorophyll maximum at ~70-110 m depths (seen in SeaSoar fluorimeter data) and a surface chlorophyll signature [seen in Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite ocean color data]. The observations also show the modulation of the biological signature at the surface by the eddy field but not of the deep chlorophyll maximum. Trichodesmium dominates the bloom nearer to Madagascar, while the diatom Rhizosolenia clevei (and its symbiont Richelia intracellularis) dominates further from the island. The surface bloom seen in the SeaWiFS data is confined to the shallow (~30 m) mixed layer. It is hypothesized that the interannual variability in bloom intensity may be due to variations in coastal upwelling and thus the supply of iron, which is a micronutrient that can limit diazotroph growth.

Srokosz, M. A.; Quartly, G. D.

2013-01-01

125

Origin of birefringence in andradite from Arizona, Madagascar, and Iran  

NASA Astrophysics Data System (ADS)

The crystal structure of four birefringent andradite samples (two from Arizona, one from Madagascar, and one from Iran) was refined with the Rietveld method, space group Iaoverline{3} d, and monochromatic synchrotron high-resolution powder X-ray diffraction (HRPXRD) data. Each sample contains an assemblage of three different cubic phases. From the electron-microprobe (EMPA) results, fine-scale intergrowths in the Arizona-2 and Madagascar samples appear homogeneous with nearly identical compositions of {Ca2.99Mg0.01}?3[{{Fe}}_{1.99}^{3 + } {{Mn}}_{0.01}^{3 + }]?2(Si2.95Al0.03 {{Fe}}_{0.02}^{3 + })?3O12, Adr98 (Arizona-2), and Adr97 (Madagascar). Both samples are near-end-member andradite, ideally {Ca3}[{{Fe}}2^{3 + }](Si3)O12, so cation ordering in the X, Y, or Z sites is not possible. Because of the large-scale intergrowths, the Arizona-1 and Iran samples contain three different compositions. Arizona-1 has compositions Adr97 (phase-1), Adr93Grs4 (phase-2), and Adr87Grs11 (phase-3). Iran sample has compositions Adr86Uv12 (phase-1), Adr69Uv30 (phase-2), and Adr76Uv22 (phase-3). The crystal structure of the three phases within each sample was modeled quite well as indicated by the Rietveld refinement statistics of reduced ?2 and overall R ( F 2) values of, respectively, 1.980 and 0.0291 (Arizona-1); 1.091 and 0.0305 (Arizona-2); 1.362 and 0.0231 (Madagascar); and 1.681 and 0.0304 (Iran). The dominant phase for each sample has the following unit-cell parameters (Å) and weight fractions (%): a = 12.06314(1), 51.93(9) (Arizona-1); 12.04889(1), 52.47(1) (Arizona-2); 12.06276(1), 52.21(8) (Madagascar); and 12.05962(2), 63.3(1) (Iran). For these dominant phases, the distances and site occupancy factors ( sofs) in terms of neutral atoms at the Ca(X), Fe(Y), and Si(Z) sites are as follows: = 2.4348, Fe-O = 2.0121(6), Si-O = 1.6508(6) Å; Ca( sof) = 0.955(2), Fe( sof) = 0.930(2), and Si( sof) = 0.917(2) (Arizona-1); = 2.4288, Fe-O = 2.0148(7), Si-O = 1.6476(7) Å; Ca( sof) = 0.953(2), Fe( sof) = 0.891(2), and Si( sof) = 0.927(2) (Arizona-2); = 2.4319, Fe-O = 2.0220(6), Si-O = 1.6460(6) Å; Ca( sof) = 0.955(2), Fe( sof) = 0.941(2), and Si( sof) = 0.939(2) (Madagascar); and = 2.4344, Fe-O = 2.0156(8), Si-O = 1.6468(8) Å; Ca( sof) = 0.928(2), Fe( sof) = 0.908(2), and Si( sof) = 0.932(3) (Iran). The sofs based on the EMPA results are similar to those obtained from the Rietveld refinement. Each phase in the HRPXRD results can be correlated with a specific chemical composition. For example, the Iran sample composition Adr63Uv30 corresponds to phase-3 that has the smallest unit-cell parameter; Adr76Uv22 corresponds to phase-1 that has the intermediate cell value; and Adr86Uv13 corresponds to phase-2 that has the largest unit-cell parameter. The bond distances compare well with those obtained from radii sum. The three different cubic phases in each sample cause strain that arises from the mismatch of the cubic unit-cell parameters and give rise to birefringence.

Antao, Sytle M.; Klincker, Allison M.

2013-07-01

126

HSP90 homologue from Madagascar periwinkle (Catharanthus roseus): cDNA sequence, regulation of protein expression and location in the endoplasmic reticulum  

Microsoft Academic Search

We describe cDNAs for a HSP90 homologue from Catharanthus roseus and studies on the regulation of expression. The largest cDNA (2670 bp) coded for a protein of 817 amino acids with a calculated size of 93 491 Da and a pI of 4.61. It contained a eucaryotic secretory signal, the endoplasmic reticulum (ER) targeting and retention signal (Lys-Asp-Glu-Leu), and the

Gudrun Schröder; Markus Beck; Johannes Eichel; Hans-Peter Vetter; Joachim Schröder

1993-01-01

127

Carbon biogeochemistry of the Betsiboka estuary (north-western Madagascar)  

Microsoft Academic Search

Madagascar’s largest estuary (Betsiboka) was sampled along the salinity gradient during the dry season to document the distribution and sources of particulate and dissolved organic carbon (POC, DOC) as well as dissolved inorganic carbon (DIC). The Betsiboka was characterized by a relatively high suspended matter load, and in line with this, low DOC\\/POC ratios (?0.4–2.5). The partial pressure of CO2

Olivier Harifidy Ralison; Alberto Vieira Borges; Frank Dehairs; J. J. Middelburg; Steven Bouillon

2008-01-01

128

Palatability and chemical defense of Phragmites australis to the marsh periwinkle snail Littoraria irrorata.  

PubMed

Coastal marsh habitats are impacted by many disturbances, including habitat destruction, pollution, and the introduction of invasive species. The common reed, Phragmites australis, has been particularly invasive in the mesohaline regions of the Chesapeake Bay, but few studies have investigated its role in trophic interactions with North American marsh consumers. The marsh periwinkle snail Littoraria irrorata is a common grazer in marshes and grazes on the native grass Spartina alterniflora. Whether this snail grazes on Phragmites has not been addressed. We found Spartina leaves to be tougher than those of Phragmites, but despite this, snails consumed significantly more Spartina than Phragmites. Subsequent experiments demonstrated that Phragmites is chemically deterrent to snails by an unknown, moderately polar, compound. Further studies are required to more fully understand the interactions between Phragmites, herbivores, and Spartina, and how they may impact marsh ecosystems. PMID:21691807

Hendricks, Lindsey G; Mossop, Hannah E; Kicklighter, Cynthia E

2011-08-01

129

Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region  

PubMed Central

The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species’ habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed. PMID:22826244

Quéméré, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Lounès

2012-01-01

130

Genetic data suggest a natural prehuman origin of open habitats in northern Madagascar and question the deforestation narrative in this region.  

PubMed

The impact of climate change and anthropogenic deforestation on biodiversity is of growing concern worldwide. Disentangling how past anthropogenic and natural factors contributed to current biome distribution is thus a crucial issue to understand their complex interactions on wider time scales and to improve predictions and conservation strategies. This is particularly important in biodiversity hotspots, such as Madagascar, dominated by large open habitats whose origins are increasingly debated. Although a dominant narrative argues that Madagascar was originally entirely covered by woodlands, which were destroyed by humans, a number of recent studies have suggested that past climatic fluctuations played a major role in shaping current biome distributions well before humans arrived. Here, we address the question of the origin of open habitats in the Daraina region in northern Madagascar, using a multiproxy approach combining population genetics modeling and remote-sensing analyses. We show that (i) contrary to most regions of Madagascar, the forest cover in Daraina remained remarkably stable over the past 60 y, and (ii) the golden-crowned sifaka (Propithecus tattersalli), a forest-dwelling lemur, underwent a strong population contraction before the arrival of the first humans, hence excluding an anthropogenic cause. Prehuman Holocene droughts may have led to a significant increase of grasslands and a reduction in the species' habitat. This contradicts the prevailing narrative that land cover changes are necessarily anthropogenic in Madagascar but does not preclude the later role played by humans in other regions in which recent lemur bottlenecks have been observed. PMID:22826244

Quéméré, Erwan; Amelot, Xavier; Pierson, Julie; Crouau-Roy, Brigitte; Chikhi, Lounès

2012-08-01

131

Himasthla elongata: Effect of infection on expression of the LUSTR-like receptor mRNA in common periwinkle haemocytes  

Microsoft Academic Search

The first mollusc mRNA coding G-protein-coupled transmembrane receptor (GP?R), homologous to human receptors LUSTR 1 (GPR107) and LUSTR 2 (GPR108), was isolated from haemocytes of common periwinkle Littorina littorea. The analyses showed that the full-length cDNA is 1935bp long and is predicted to encode a 614 amino acid protein (named Lit-LUSTR) with a calculated molecular mass of 69.6kDa and theoretical

A. M. Gorbushin; A. V. Klimovich; N. V. Iakovleva

2009-01-01

132

Congruence between allozyme and RAPD data in assessing macrogeographical genetic variation in the periwinkle Littorina striata (Mollusca, Gastropoda)  

Microsoft Academic Search

The population genetic structure of the Macaronesian planktonic-developing periwinkle Littorina striata was analysed, using random amplified polymorphic DNA analysis (RAPD). Two primers, yielding six polymorphic loci, were surveyed to infer the population genetic structure of five geographically separated populations (i.e. 10–2000 km). Biased and unbiased allele frequency and heterozygosity levels were estimated and were found to be highly similar. As

H de Wolf; T Backeljau; R Verhagen

1998-01-01

133

Large-scale patterns of shell variation in Littorina striata , a planktonic developing periwinkle from Macaronesia (Mollusca: Prosobranchia)  

Microsoft Academic Search

Littorina striata King and Broderip, 1832 is a strictly Macaronesian, intertidal periwinkle with planktonic development. The species displays\\u000a a high degree of shell variation involving size and sculpture (nodulose vs smooth shells). The present work provides a preliminary\\u000a account of some aspects of this shell variation on wave-exposed shores over the entire geographical range of the species.\\u000a Based on morphological

H. De Wolf; T. Backeljau; S. Van Dongen; R. Verhagen

1998-01-01

134

When Madagascar produced natural rubber: a brief, forgotten yet informative history.  

E-print Network

1 When Madagascar produced natural rubber: a brief, forgotten yet informative history. P. Danthu (1, Madagascar, like other western African countries, was a production zone for forest rubber destined for export Madagascar occupies a modest position on the world rubber market at that time, the exploitation of rubber

Boyer, Edmond

135

Immune Responses to Plague Infection in Wild Rattus rattus, in Madagascar: A Role in Foci Persistence?  

E-print Network

Immune Responses to Plague Infection in Wild Rattus rattus, in Madagascar: A Role in Foci, Antananarivo, Madagascar Abstract Background: Plague is endemic within the central highlands of Madagascar susceptible to plague, rapidly dying after infection inducing the spread of infected fleas and, therefore

Paris-Sud XI, Université de

136

The Spread of Influenza A(H1N1)pdm09 Virus in Madagascar Described by a Sentinel Surveillance  

E-print Network

The Spread of Influenza A(H1N1)pdm09 Virus in Madagascar Described by a Sentinel Surveillance Virology Unit, National Influenza Center, Institut Pasteur de Madagascar, Antananarivo, Madagascar, 3 Malagasy Ministry of Health, Antananarivo, Madagascar Abstract Background: The influenza A(H1N1)pdm09 virus

Paris-Sud XI, Université de

137

Insatiable demands: Income, energy and environmental policy in Madagascar  

SciTech Connect

The island nation of Madagascar is suffering the collision of three distinct trends: economic stagnation, a rapidly expanding population and a severely threatened natural resource base. Demands for growth, new energy reserves and environmental conservation, especially of forest resources, are creating a policy dilemma for both government officials and donors. This study seeks to bring new evidence to bear on this policy dilemma. Primary data on urban household income, family size and consumption of various energy types are used to test two main hypothesis (1) that charcoal, which constitutes the fuel of choice for a vast majority of the sample, is a normal rather than an inferior good, and (2) that demand for wood-fuels constitutes a genuine threat to the viability of the forest resource. The data indicate that income elasticities of demand for charcoal are positive over a broad range of per capita income levels, revealing that charcoal is, indeed a normal good for a large portion of the population represented by the sample. A model of forest degradation is built which establishes a clear link between wood-fuel demand and forest degradation. Together, these findings make clear that under current income patterns, and for the forseeable future, charcoal is a normal good and its consumption by urban residents constitutes a serious threat to the natural forest resource. The study concludes with a policy analysis which identifies existing market failures due to government policies and recommends changes based on tested policy prescriptions in other parts of the developing world.

Shaw, C.L.

1993-01-01

138

Malagasy dialects and the peopling of Madagascar  

PubMed Central

The origin of Malagasy DNA is half African and half Indonesian, nevertheless the Malagasy language, spoken by the entire population, belongs to the Austronesian family. The language most closely related to Malagasy is Maanyan (Greater Barito East group of the Austronesian family), but related languages are also in Sulawesi, Malaysia and Sumatra. For this reason, and because Maanyan is spoken by a population which lives along the Barito river in Kalimantan and which does not possess the necessary skill for long maritime navigation, the ethnic composition of the Indonesian colonizers is still unclear. There is a general consensus that Indonesian sailors reached Madagascar by a maritime trek, but the time, the path and the landing area of the first colonization are all disputed. In this research, we try to answer these problems together with other ones, such as the historical configuration of Malagasy dialects, by types of analysis related to lexicostatistics and glottochronology that draw upon the automated method recently proposed by the authors. The data were collected by the first author at the beginning of 2010 with the invaluable help of Joselinà Soafara Néré and consist of Swadesh lists of 200 items for 23 dialects covering all areas of the island. PMID:21632612

Serva, Maurizio; Petroni, Filippo; Volchenkov, Dima; Wichmann, Søren

2012-01-01

139

Understanding the Persistence of Plague Foci in Madagascar  

PubMed Central

Plague, a zoonosis caused by Yersinia pestis, is still found in Africa, Asia, and the Americas. Madagascar reports almost one third of the cases worldwide. Y. pestis can be encountered in three very different types of foci: urban, rural, and sylvatic. Flea vector and wild rodent host population dynamics are tightly correlated with modulation of climatic conditions, an association that could be crucial for both the maintenance of foci and human plague epidemics. The black rat Rattus rattus, the main host of Y. pestis in Madagascar, is found to exhibit high resistance to plague in endemic areas, opposing the concept of high mortality rates among rats exposed to the infection. Also, endemic fleas could play an essential role in maintenance of the foci. This review discusses recent advances in the understanding of the role of these factors as well as human behavior in the persistence of plague in Madagascar. PMID:24244760

Andrianaivoarimanana, Voahangy; Kreppel, Katharina; Elissa, Nohal; Duplantier, Jean-Marc; Carniel, Elisabeth; Rajerison, Minoarisoa; Jambou, Ronan

2013-01-01

140

Tropical Cyclone Kesiny northeast of Madagascar, Indian Ocean  

NASA Technical Reports Server (NTRS)

Tropical Cyclone Kesiny can be seen over the Indian Ocean in this true color image taken on May 6, 2002, at 6:45 UTC by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. When this image was taken, the cyclone was several hundred miles east of northern Madagascar and packing winds of up to 120 kilometers (75 miles) per hour. As the cyclone continues its approach southwest into Madagascar, it is forecast to increase in intensity and generate sustained winds of up to 139 kilometers (86 miles) per hour. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

2002-01-01

141

Holocene Indian Ocean Cosmic Impacts: The Megatsunami Chevron Evidence From Madagascar  

NASA Astrophysics Data System (ADS)

The 2.6 million year Quaternary period terrestrial physical record lacks definitive crater evidence for major regional catastrophic impacts by asteroids and comets other than the 10.5-km diameter Botsumtwi structure in Ghana and the 14.0-km diameter Zhamanshin structure in Kazakhstan [1] dating between about 900 and 1100 kya. Current cosmic impact rate models suggest that an average of between 3-6 globally catastrophic impacts should have occurred on the Earth during the Quaternary, along with several additional significant regional impacts in addition to Zhamanshin and Botsumtwi. These models and data indicate that the great majority of the "missing" major impact locations would likely have occurred in poorly studied oceanic settings. Only recently have Late Quaternary and Holocene period coastal paleo-megatsunami chevron deposits been defined in the Caribbean and along the western coasts of Australia, along with the suggestion that some may have been created by oceanic cosmic impacts in distinction to those caused by landslips, eruptions, and seismic events. We investigate the possibility that many or most megatsunami chevrons occurring along the southern coast of Madagascar were caused by two or more major Holocene Indian Ocean cosmic impacts. This hypothesis is based on an initial study of the worldwide archaeological and anthropological record, and the preliminary study of satellite images of the chevrons, selected Indian Ocean deep-sea cores, sea-floor bathymetry, and physical examination of the Madagascar deposits themselves. Candidate Indian Ocean impact structures are identified and correlated with the southern Madagascar megatsunami chevron deposits. [1] Masse, W.B. 2007 The Archaeology and Anthropology of Quaternary Period Cosmic Impact. In Bobrowsky, P.T. & Rickman, H. (eds.)Comets/Asteroid Impacts and Human Society. Springer, Berlin (in press).

Masse, W.; Bryant, E.; Gusiakov, V.; Abbott, D.; Rambolamana, G.; Raza, H.; Courty, M.; Breger, D.; Gerard-Little, P.; Burckle, L.

2006-12-01

142

Predicting Plant Diversity Patterns in Madagascar: Understanding the Effects of Climate and Land Cover Change in a Biodiversity Hotspot  

PubMed Central

Climate and land cover change are driving a major reorganization of terrestrial biotic communities in tropical ecosystems. In an effort to understand how biodiversity patterns in the tropics will respond to individual and combined effects of these two drivers of environmental change, we use species distribution models (SDMs) calibrated for recent climate and land cover variables and projected to future scenarios to predict changes in diversity patterns in Madagascar. We collected occurrence records for 828 plant genera and 2186 plant species. We developed three scenarios, (i.e., climate only, land cover only and combined climate-land cover) based on recent and future climate and land cover variables. We used this modelling framework to investigate how the impacts of changes to climate and land cover influenced biodiversity across ecoregions and elevation bands. There were large-scale climate- and land cover-driven changes in plant biodiversity across Madagascar, including both losses and gains in diversity. The sharpest declines in biodiversity were projected for the eastern escarpment and high elevation ecosystems. Sharp declines in diversity were driven by the combined climate-land cover scenarios; however, there were subtle, region-specific differences in model outputs for each scenario, where certain regions experienced relatively higher species loss under climate or land cover only models. We strongly caution that predicted future gains in plant diversity will depend on the development and maintenance of dispersal pathways that connect current and future suitable habitats. The forecast for Madagascar’s plant diversity in the face of future environmental change is worrying: regional diversity will continue to decrease in response to the combined effects of climate and land cover change, with habitats such as ericoid thickets and eastern lowland and sub-humid forests particularly vulnerable into the future. PMID:25856241

Brown, Kerry A.; Parks, Katherine E.; Bethell, Colin A.; Johnson, Steig E.; Mulligan, Mark

2015-01-01

143

The structure of the lithosphere and asthenosphere beneath Mozambique and Madagascar from combined surface wave and ambient noise tomography  

NASA Astrophysics Data System (ADS)

We present results based on applying the two-plane wave method to the observed amplitude and phase of fundamental mode surface waves from the NSF-funded MACOMO IRIS PASSCAL broadband seismometer deployment in Madagascar and Mozambique. The two-plane wave method (Forsyth and Li, 2005) involves modeling arriving surface waves by a two-plane-wave field. Combining this method with ambient noise will allow the joint inversion of phase velocities from 5 to 180 s, to generate a high-resolution 3-D shear wave velocity model from the surface to a depth of ~200 km beneath Madagascar, Mozambique and the surrounding regions. Using the two-plane wave method, the phase and amplitude of fundamental mode Rayleigh waves from distant earthquakes recorded at MACOMO are inverted for 2-D phase velocity maps at periods from 18 to 180 s. The ambient noise method (a separate study) is limited to short periods and therefore it is sensitive only to the crust and uppermost mantle structure. The 3-D shear-wave velocity structure beneath East Africa (Mozambique and Madagascar) where the East African Orogeny was instrumental in the amalgamation of Gondwana (~540 Ma) is investigated by using the implicit relation between phase-velocity dispersion and shear-wave structure. The phase velocities, at selected periods and at each node of the phase velocity maps, are inverted for a 1-D structure; the 1-D models at each node form the 3-D shear-wave model. Phase-velocity tomographic images show 2-D lateral variations in phase velocities at each period. Preliminary results show that above periods of 124 sec we noticed a rapid vertical transition to low phase velocities beneath southern Madagascar.

Shore, P.; Aleqabi, G. I.; Wysession, M. E.; Pratt, M. J.; Wiens, D. A.; Nyblade, A.; Rambolamana, G.; Rakotondraibe, T.; Sy Tanjona Andriampenomanana ny Ony, F.

2013-12-01

144

Arsenic species extraction of biological marine samples (Periwinkles, Littorina littorea) from a highly contaminated site.  

PubMed

Arsenic is ubiquitous in the tissues of marine organisms and in uncontaminated environments it is dominantly present as the highly soluble and easily extractable non-toxic arsenical, arsenobetaine. However in contaminated environments, higher proportions of inorganic arsenic, which is much less soluble, are accumulated into the tissues of marine organisms, resulting in lower extraction efficiencies (defined as the percent extracted arsenic of the total arsenic). This study carried out a comparative analysis between three different two-step arsenic extraction methods based on Foster et al. [27] from highly contaminated tissue of the marine periwinkle, Littorina littorea. The first extraction step used 100% water, 1:1 methanol-water, or a 9:1 methanol-water as the extraction solvent and the second step consisted of a gently heated dilute nitric acid extraction. The optimized two step extraction method was 1:1 methanol-water extraction followed by a 2% HNO(3) extraction, based on maximum amounts of extracted species, including organoarsenic species. PMID:22265486

Whaley-Martin, K J; Koch, I; Reimer, K J

2012-01-15

145

Cryopreservation of Alkaloid-Producing Cell Cultures of Periwinkle (Catharanthus roseus) 1  

PubMed Central

A procedure for cryogenic storage of alkaloid producing cell lines of periwinkle, Catharanthus roseus (L.) G. Don., has been developed. The procedure differs from established cryopreservation protocols in several aspects. Specifically, 4-day-old suspension subcultures of three cell lines were precultured in nutrient media supplemented with 1 molar sorbitol for 6 to 20 hours. The cells were then incubated in nutrient media with 1 molar sorbitol plus 5% DMSO in an ice bath for 1 hour and, thereafter, were frozen in this solution at a cooling rate of 0.5°C per minute to ?40°C prior to immersion in liquid nitrogen (LN). After rapid thawing in a 40°C water bath, the regrowth of LN stored cells was achieved by transferring them without washing onto filter paper discs over nutrient media solidified with agar for a period of 4 to 5 hours. The filter paper discs with the cells were then transferred to fresh media of the same composition for regrowth. The viability immediately after thawing as evaluated by the 2,3,5-triphenyl tetrazolium chloride method was about 60% of controls. Suspension cultures established from LN stored cells retained the capability for alkaloid synthesis and accumulation. Images Fig. 8 PMID:16663695

Chen, Tony H. H.; Kartha, Kutty K.; Leung, Nicholas L.; Kurz, Wolfgang G. W.; Chatson, Kenneth B.; Constabel, Friedrich

1984-01-01

146

Structural mapping and analysis of a Madagascar Precambrian shear zone using enhanced Landsat Thematic Mapper Data  

SciTech Connect

Recently, the west coast of Madagascar has become a frontier region for petroleum exploration. Major structures in the Precambrian shield of Madagascar may have a strong control on the development of sedimentary basins, as has been documented in the Morondava basin. The 2.5-3.0+ Ga shield of Madagascar is an amphibolite- to granulite-grade metamorphic gneiss terrain, intruded by anorthosites and 550-Ma granites and pegmatites. Landsat Thematic Mapper data provides a cost-effective method for regional-scale structural mapping of this poorly known terrain. A five-component linear mixing model has been used to enhance the lithologic information in this six-band data. Lithologic component images thus produced utilize the full geologic spectral range of the data. A preliminary structural geologic map compiled from the component images has greater detail than existing maps at 1:100,000 scale, to which it has been compared. The Ankafotra-Saririaky shear zone has been identified as a north-northeast-trending, 15- to 20-km-wide region of appressed folds, attenuated layering, and subparallel faults on the western side of the shield. Two anorthosite massifs that occur within this shear zone have the structural characteristics of boudins in a ductile matrix. The shear deformed a preexisting terrain of poly-phase folding, characterized by tight folds and complex fold interference structures displayed by basins and domes on a scale of 10 km. Enhanced remote sensing data can be used to characterize the nature and mechanism of shear deformation in such zones.

Kilmer, D.S.; Duncan, I.J. (Washington Univ., St. Louis, MO (USA))

1990-05-01

147

A Conservation Strategy for the Amphibians of Madagascar  

E-print Network

A Conservation Strategy for the Amphibians of Madagascar Monografie del Museo Regionale di Scienze of Braunschweig, Braunschweig. Ché WELDON1 , Louis DU PREEZ1 , Miguel VENCES2 Lack of detection of the amphibian chytridiomycosis can have catastrophic effects on amphibian populations leading to declines and even extinctions

Vences, Miguel

148

Satellite imagery, human ecology, anthropology, and deforestation in Madagascar  

Microsoft Academic Search

Satellite images were used to determine rates of deforestation over the past 35 years and to identify current deforestation hotspots in the eastern rainforests and in the dry endemic forests of southern Madagascar. The analysis of population trends, topography, and coincident ethnographic research points to a number of different factors influencing deforestation in these regions. Each of these factors generates

Robert W. Sussman; Glen M. Green; Linda K. Sussman

1994-01-01

149

Has Madagascar Lost Its Exceptional Leptospirosis Free-Like Status?  

PubMed Central

Background Leptospirosis is a widespread but underreported cause of morbidity and mortality. It has rarely been reported in either humans or animals in Madagascar. Methods We conducted a cross-sectional survey of the inhabitants in Moramanga, Madagascar, in June 2011, to estimate the prevalence of human infection using the microscopic agglutination test (MAT). This activity was carried out as part of a workshop implemented by the Pasteur Institute of Madagascar, focusing on surveillance with a one week field study and targeting the health staff of the district level. Results In total, we sampled 678 inhabitants from 263 households. The sex ratio (M/F) was 0.65 and the mean age 26.7 years. We obtained a value of 2.9% for the first recorded seroprevalence of this disease in the human community of Moramanga. Questionnaire responses revealed frequent contacts between humans and rodents in Moramanga. However, activities involving cattle were identified as a risk factor significantly associated with seropositivity (OR=3). Conclusion Leptospirosis remains a neglected disease in Madagascar. This study highlights the need to quantify the public health impact of this neglected disease in a more large scale, in all the country and to establish point-of-care laboratories in remote areas. PMID:25874381

Ratsitorahina, Maherisoa; Rahelinirina, Soanandrasana; Michault, Alain; Rajerison, Minoarisoa; Rajatonirina, Soatiana; Richard, Vincent

2015-01-01

150

Sauropod dinosaur osteoderms from the Late Cretaceous of Madagascar  

Microsoft Academic Search

Osteoderms are bones embedded within the dermis, and are common to select members of most major tetrapod lineages. The largest known animals that bear osteoderms are members of Titanosauria, a diverse clade of sauropod dinosaurs. Here we report on two titanosaur osteoderms recovered from the Upper Cretaceous Maevarano Formation of Madagascar. Each osteoderm was discovered in association with a partial

Michael D'Emic; Raymond Rogers; Matthew Vickaryous; Amanda Cagan; Kristina Curry Rogers

2011-01-01

151

Family Background, School Characteristics, and Children's Cognitive Achievement in Madagascar  

ERIC Educational Resources Information Center

This paper uses linked household, school, and test score data from Madagascar to investigate the relation of household characteristics and school factors to the cognitive skills of children ages 8-10 and 14-16. In contrast to most achievement test studies in developing countries, the study uses representative rather than school-based samples of…

Glick, Peter; Randrianarisoa, Jean Claude; Sahn, David E.

2011-01-01

152

Phylogeography and Molecular Epidemiology of Yersinia pestis in Madagascar  

E-print Network

Environmental Research Institute, University College Cork, Cork, Ireland Abstract Background: Plague of plague in Madagascar. We find relatively high levels of VNTR diversity in addition to several SNP. Such transfers have resulted in the reintroduction and establishment of plague in the port city of Mahajanga

Boyer, Edmond

153

An old adaptive radiation of forest dung beetles in Madagascar  

Microsoft Academic Search

Adaptive radiations of mammals have contributed to the exceptionally high levels of biodiversity and endemism in Madagascar. Here we examine the evolutionary history of the endemic dung beetle tribe Helictopleurini (Scarabaeidae) and its relationship to the widely distributed Oniticellini and Onthophagini. Helictopleurini species are dependent on mammals for their resources. We date the single origin of the tribe at 37

Helena Wirta; Luisa Orsini; Ilkka Hanski

2008-01-01

154

Cyclopoid copepods associated with antipatharian coelenterates in Madagascar  

Microsoft Academic Search

Previous work (in i960) at Nosy Bé, in northwestern Madagascar, resulted in the collection by dredging of the antipatharian Stichopathes echinulata Brook parasitized by the copepod Vahinius petax Humes, 1967. More recently (in 1964 and 1967) I have obtained by SCUBA diving several other antipatharians with which the copepods described below were associated. The collection in 1964 was made as

A. G. Humes

1969-01-01

155

Autochthonous Melioidosis in Humans, Madagascar, 2012 and 2013  

PubMed Central

Melioidosis is an often fatal infectious disease affecting humans and animals in the tropics. Only sporadic cases have been reported from Africa and the Indian Ocean region. We describe 2 confirmed autochthonous cases of human melioidosis in Madagascar, both from novel genotypes of Burkholderia pseudomallei. PMID:25272365

Djaomazala, Innocente; Dubois-Cauwelaert, Natasha; Raharimanga, Vaomalala; Ralison, Fidiarivony; Herindrainy, Perlinot; Andriamalala, Nivosoa C.; Sarovich, Derek S.; Mayo, Mark; Kaestli, Mirjam; Currie, Bart J.

2014-01-01

156

Corps de la Paix Madagascar Livre du Formateur. Langue: Sakalava (Peace Corps Madagascar Teacher's Manual. Language: Sakalava).  

ERIC Educational Resources Information Center

This teacher's manual for Sakalava, a dialect of Malagasy, is designed for the specific language instruction needs of Peace Corps personnel in Madagascar. It is written primarily in French and Sakalava, with some titles in English. It consists of 29 topical lessons, each geared to a specific domain and competency and containing information on…

Tshiangale, Mupemba Wa

157

Corps de la Paix Madagascar Livre du Stagiare. Langue: Malagasy Ofisialy (Peace Corps Madagascar Volunteer Manual. Language: Official Malagasy).  

ERIC Educational Resources Information Center

This manual for Malagasy is designed for the specific language instruction needs of Peace Corps personnel working in Madagascar. It is written primarily in English and Malagasy, with introductory sections in French. It consists of 29 topical lessons, each geared to a specific domain and competency and containing information on needed materials,…

Tshiangale, Mupemba Wa

158

IDiversite et Endemisme a Madagascar pp : 229-242 Aout 2000 ISBN 2-903700-04-4 \\ POLYPHYLY OF TOMOPTERNA (AMPHIBIA: RANIDAE) BASED ON  

E-print Network

of Tomopterna are not informative regarding continental drift and biogeographic Madagascar-India relationships, Molecular phylogeny, Madagascar, India, South Africa, Continental drift, Reproductive modes RESUME.- Les

159

The Application of TOMS Ozone, Aerosol and UV-B Data to Madagascar Air Quality Determination  

NASA Technical Reports Server (NTRS)

Total Ozone Mapping Spectrometer (TOMS) data products for the area of Madagascar are presented. In addition to total ozone, aerosols and UV-B tropospheric ozone results are shown from 1979 to the present. Tropospheric ozone over Africa and Madagascar is enhanced by 10 to 15 DU in October. This maximum coincides with the time of maximum biomass area burning in Africa and Madagascar. Ozone observations were made from 1979 to 1999 using the TOMS tropospheric ozone convective cloud differential method. As a result of easterly trade winds, ozone originating on Madagascar is transported to the west over the Mozambique Channel. In El Nino years higher level westerly winds descend to transport low level ozone easterly. This results in African continental ozone being transported east of Madagascar. Long range transport of African ozone is observed during El Nino periods. The potential of TOMS and other space data for use in public education and research on Madagascar air quality is demonstrated.

Aikin, A.C.; Einaudi, Franco (Technical Monitor)

2000-01-01

160

Mesoscale eddy variability in the southern extension of the East Madagascar Current: Seasonal cycle, energy conversion terms, and eddy mean properties  

NASA Astrophysics Data System (ADS)

In this study, we used more than 17 years of satellite altimetry observations and output from an ocean model to investigate the mesoscale eddy variability and forcing mechanisms to the south of Madagascar. Analysis of energy conversion terms in the model has shown seasonality on eddy formation, both by barotropic and baroclinic instabilities: maximum in winter (JJA) and minimum in summer (DJF). The eddies were mainly formed in the upper ocean (0-300 m) and at intermediate depths (800-2000 m) by barotropic and baroclinic instabilities, respectively. The former dominated in the southeastern margin of Madagascar, and the latter to the southwest, where the South-East Madagascar Current (SEMC) separates from the continental shelf. Seasonality of the eddy formation appeared linked with the seasonal intensification of the SEMC. The energy conversion terms indicated that the eddies have a significant contribution to the large-scale circulation, but not being persistent throughout the year, occurring mainly during the fall season (MAM). Eddy demography from altimetry and model provided information on eddy preferential sites for birth, annual occurrence (6-13 per year), eddy mean diameter (124-178 km), mean amplitude (9-28 cm), life-time (90-183 days), and maximum traveling distances (325-1052 km). Eddies formed to the southwest of Madagascar exhibited distinct characteristics from those formed in the southeast. Nevertheless, all eddies were highly nonlinear, suggesting that they are potential vectors of connectivity between Madagascar and Africa. This may have a significant impact on the ecology of this region.

Halo, Issufo; Penven, Pierrick; Backeberg, Björn; Ansorge, Isabelle; Shillington, Frank; Roman, Raymond

2014-10-01

161

VARIATION IN THE SHELL MORPHOMETRICS OF THE COMMON PERIWINKLE, LITTORINA LITTOREA AND THE DOGWHELK, NUCELLA LAPILLUS, ON THE NORTH-EAST COAST OF THE BRITISH ISLES  

Microsoft Academic Search

The common periwinkle, Littorina littorea, and the dogwhelk, Nucella Lapillus, are both gastropods that reproduce in very different ways. L. littorea is a pelagic disperser, a method resulting in little or no genetic relation of proximal populations and N. lapillus develop and hatch in the same area from whence their parents came resulting in high degrees of genetic relatedness in

R. M. EDKINS

162

Modulation of mitogen-activated protein kinases (MAPK) activity in response to different immune stimuli in haemocytes of the common periwinkle Littorina littorea  

Microsoft Academic Search

The modulation of mitogen-activated protein kinase (MAPK) activity in haemocytes of the common periwinkle (Littorina littorea) in response to immune challenges by lipopolysaccharide from Echerichia coli (LPS), mannan from baker's yeast Saccharomyces cerevisiae and secretory-excretory products (SEP) of trematodes Himasthla elongata (Echinostomatidae) or after the treatment with phorbol ester (PMA) has been studied by Western blotting using affinity purified rabbit

Nadya V. Iakovleva; Alexander M. Gorbushin; Kenneth B. Storey

2006-01-01

163

The role of demography and markets in determining deforestation rates near Ranomafana National Park, Madagascar.  

PubMed

The highland forests of Madagascar are home to some of the world's most unique and diverse flora and fauna and to some of its poorest people. This juxtaposition of poverty and biodiversity is continually reinforced by rapid population growth, which results in increasing pressure on the remaining forest habitat in the highland region, and the biodiversity therein. Here we derive a mathematical expression for the subsistence of households to assess the role of markets and household demography on deforestation near Ranomafana National Park. In villages closest to urban rice markets, households were likely to clear less land than our model predicted, presumably because they were purchasing food at market. This effect was offset by the large number of migrant households who cleared significantly more land between 1989-2003 than did residents throughout the region. Deforestation by migrant households typically occurred after a mean time lag of 9 years. Analyses suggest that while local conservation efforts in Madagascar have been successful at reducing the footprint of individual households, large-scale conservation must rely on policies that can reduce the establishment of new households in remaining forested areas. PMID:19536282

Brooks, Christopher P; Holmes, Christopher; Kramer, Karen; Barnett, Barry; Keitt, Timothy H

2009-01-01

164

Rural livelihoods and access to natural capital: Differences between migrants and non-migrants in Madagascar  

PubMed Central

BACKGROUND Although natural resources play a central role in rural livelihoods across the globe, little research has explored the relationship between migration and natural capital use, particularly in combination with other livelihood capitals (i.e., human, social, financial and physical). OBJECTIVE Grounded in the rural livelihood framework, this paper explores the association between the livelihood capital availability, especially natural capital, for migrants and non-migrants in rural Madagascar. METHODS Data from the 2008/2009 Demographic and Health Survey are used in combination with satellite imagery of vegetation coverage (Normalized Difference Vegetation Index, NDVI) to proxy natural resources. Hierarchical multilevel models allow for inclusion of cross-level interactions between migrant status and proximate natural resources as determinants of the status of livelihood assets. RESULTS Three key findings emerge. First, higher levels of proximate natural resources are associated with greater financial, human, and social capital for both migrants and non-migrants. Second, migrants have, on average, greater financial, physical, human, and social capital than non-migrants, and urban-to-rural migrants do exceptionally well on all capital asset categories. Third, migrants residing in areas with higher levels of natural capital tend to have significantly higher levels of human capital (education). CONCLUSION Although we cannot examine livelihood strategies per se, the results suggest variation in livelihood potential among migrants and non-migrants in rural Madagascar, with migrants tending to have greater capital assets. In addition, access to natural resources is a central livelihood strategy. PMID:25364297

Nawrotzki, Raphael J.; Hunter, Lori M.; Dickinson, Thomas W.

2013-01-01

165

Himasthla elongata: effect of infection on expression of the LUSTR-like receptor mRNA in common periwinkle haemocytes.  

PubMed

The first mollusc mRNA coding G-protein-coupled transmembrane receptor (GPcapital ES, CyrillicR), homologous to human receptors LUSTR 1 (GPR107) and LUSTR 2 (GPR108), was isolated from haemocytes of common periwinkle Littorina littorea. The analyses showed that the full-length cDNA is 1935 bp long and is predicted to encode a 614 amino acid protein (named Lit-LUSTR) with a calculated molecular mass of 69.6 kDa and theoretical isoelectric point 7.59. Pair-wise comparisons between Lit-LUSTR and LUSTR proteins from human or mouse have approximately 38% identity and 56% similarity. Lit-LUSTR clusters with LUSTR-A sub-family proteins and is a first characterization of proteins containing Lung7TM-R domain in Mollusca. Significant differences were found between the Lit-LUSTR mRNA levels in haemocytes of healthy periwinkles and those naturally infected with the echinostome trematode Himasthla elongata. Down regulated expression of the LUSTR-like receptor caused by infection illustrates modification of the haemocyte receptor system and may be attributed to the previously demonstrated greater numbers of "immature" haemocytes in the circulation of infected snails. PMID:19460375

Gorbushin, A M; Klimovich, A V; Iakovleva, N V

2009-09-01

166

Immunological and physiological responses of the periwinkle Littorina littorea during and after exposure to the toxic dinoflagellate Alexandrium minutum.  

PubMed

Species of the dinoflagellate genus Alexandrium produce phycotoxins responsible for paralytic shellfish poisoning. Blooms of Alexandrium minutum reach very high concentrations of vegetative cells in the water column; and when these blooms occur, large numbers of toxic cysts can be produced and deposited on sediments becoming available to benthic species. The present study investigated the potential effect of exposure to toxic cysts of A. minutum on the periwinkle Littorinalittorea. Snails were exposed for nine days to pellicle cysts of toxic and non-toxic dinoflagellates, A. minutum and Heterocapsa triquetra, respectively, followed by six days of depuration while they were fed only H. triquetra. Toxin accumulation, condition index, immune and histopathological responses were analyzed. Histological alterations were also monitored in snails exposed to a harmful A. minutum bloom, which naturally occurred in the Bay of Brest. Snails exposed to toxic cysts showed abnormal behavior that seems to be toxin-induced and possibly related to muscle paralysis. Periwinkles accumulated toxins by preying on toxic cysts and accumulation appeared dependent on the time of exposure, increasing during intoxication period but tending to stabilize during depuration period. Toxic exposure also seemed to negatively affect hemocyte viability and functions, as ROS production and phagocytosis. Histological analyses revealed that toxic exposure induced damages on digestive organs of snails, both in laboratory and natural systems. This study demonstrates that an exposure to the toxic dinoflagellate A. minutum leads to sublethal effects on L. littorea, which may alter individual fitness and increase the susceptibility of snails to pathogens and diseases. PMID:25621399

Neves, Raquel A F; Figueiredo, Gisela M; Valentin, Jean Louis; da Silva Scardua, Patricia Mirella; Hégaret, Hélène

2015-03-01

167

Possible Fruit Protein Effects on Primate Communities in Madagascar and the Neotropics  

PubMed Central

Background The ecological factors contributing to the evolution of tropical vertebrate communities are still poorly understood. Primate communities of the tropical Americas have fewer folivorous but more frugivorous genera than tropical regions of the Old World and especially many more frugivorous genera than Madagascar. Reasons for this phenomenon are largely unexplored. We developed the hypothesis that Neotropical fruits have higher protein concentrations than fruits from Madagascar and that the higher representation of frugivorous genera in the Neotropics is linked to high protein concentrations in fruits. Low fruit protein concentrations in Madagascar would restrict the evolution of frugivores in Malagasy communities. Methodology/Principal Findings We reviewed the literature for nitrogen concentrations in fruits from the Neotropics and from Madagascar, and analyzed fruits from an additional six sites in the Neotropics and six sites in Madagascar. Fruits from the Neotropical sites contain significantly more nitrogen than fruits from the Madagascar sites. Nitrogen concentrations in New World fruits are above the concentrations to satisfy nitrogen requirements of primates, while they are at the lower end or below the concentrations to cover primate protein needs in Madagascar. Conclusions/Significance Fruits at most sites in the Neotropics contain enough protein to satisfy the protein needs of primates. Thus, selection pressure to develop new adaptations for foods that are difficult to digest (such as leaves) may have been lower in the Neotropics than in Madagascar. The low nitrogen concentrations in fruits from Madagascar may contribute to the almost complete absence of frugivorous primate species on this island. PMID:20016841

Ganzhorn, Jörg U.; Arrigo-Nelson, Summer; Boinski, Sue; Bollen, An; Carrai, Valentina; Derby, Abigail; Donati, Giuseppe; Koenig, Andreas; Kowalewski, Martin; Lahann, Petra; Norscia, Ivan; Polowinsky, Sandra Y.; Schwitzer, Christoph; Stevenson, Pablo R.; Talebi, Mauricio G.; Tan, Chia; Vogel, Erin R.; Wright, Patricia C.

2009-01-01

168

Satellite Observations of Enhanced Tropospheric Ozone Associated with Biomass Burning in Africa and Madagascar  

NASA Technical Reports Server (NTRS)

Tropospheric ozone over Africa and Madagascar is enhanced by 10 to 15 DU in October. This maximum coincides with the time of maximum biomass area burning in Africa and Madagascar. Ozone observations were made from 1979 to 1999 using the TOMS tropospheric ozone convective cloud differential method. As a result of easterly trade winds, ozone originating on Madagascar is transported to the west over the Mozambique Channel. In El Nino years higher level westerly winds descend to transport low level ozone easterly. This results in African continental ozone being transported east of Madagascar. Long range transport of African ozone is observed during El Nino periods.

Aikin, A. C.; Ziemke, J. R.; Thorpe, A.; Einaudi, Franco (Technical Monitor)

2000-01-01

169

Women's knowledge in Madagascar: a health needs assessment study.  

PubMed

Nutritional and hygienic practices contribute to high morbidity and mortality rates related to malnutrition in Madagascar. This study, a research effort that brought together charitable organisations, non-governmental organisations (NGOs) and university collaborators, investigates women's health knowledge in the Anosy region of Madagascar. The needs assessment sought to characterise women's knowledge and understanding of nutrition and hygiene. Eight focus groups of 13-60 women each were conducted in the seven most impoverished communes of the Anosy region (n=373). Participants were recruited with the aid of a UK-Malagasy partnered NGO, Azafady. Study findings show that women fully understand the interplay between poor nutrition, hygiene and malnutrition but are unable to change everyday practices because the barriers to better nutrition and hygiene seem beyond their control. These findings may be used to prioritise projects and research seeking to improve nutrition and hygiene, thus reducing malnutrition in the Anosy region. PMID:21416417

Dell, Evelyn M; Erikson, S L; Andrianirina, E; Smith, Gabrielle

2012-01-01

170

Seismic Control on Location of Lavakas (Midslope Gullies) in Madagascar  

Microsoft Academic Search

Madagascar's central highlands are deeply weathered, with 1-2 m of laterite overlying 10s of metres of saprolite. These unstable materials sit at altitudes on the order of 1000m in recently uplifted, steep terrain characterised by convex hills with slopes averaging 25 degrees and local ridge-valley elevation changes of 100- 500 m. In many areas these slopes bear numerous erosional features

F. Rasoazanamparan; R. Cox; S. J. Macklin; A. Rakotondrazafy

2006-01-01

171

Octocorallia from North-Western Madagascar (Part I)  

Microsoft Academic Search

INTRODUCTION During the years 1960, 1963, 1964 and 1967 Dr. Arthur G. Humes, Boston University, Massachusetts, U.S.A., collected a number of octocorals in the waters north-west of Madagascar, near the islands Nosy Bé, Nosy Komba, Ambariobe (a small island nearly between Nosy Komba and Nosy Bé), Tany Kely (a small island to the south of Nosy Bé), Nosy Faly, Isles

J. Verseveldt

1969-01-01

172

Chapelieriamagna, a new species of Rubiaceae from eastern Madagascar.  

PubMed

A new species of Chapelieria was discovered during a recent field trip to the Masoala National Park in eastern Madagascar, and is described here as Chapelieriamagna Kainul., sp. nov. This species is readily distinguishable from previously described species of the genus by its quadrangular shoots, triangular-calyptrate stipules, sessile leaves, pubescent styles, and ridged fruits. It also differs in the larger number of ovules and the much larger size of leaves and fruits. PMID:25698895

Kainulainen, Kent; Razafimandimbison, Sylvain G

2015-01-01

173

Field Museum Researchers Help Trace Origin of Madagascar's Mammals  

NSDL National Science Digital Library

Chicago's Field Museum of Natural History (FMNH) Web site currently features museum-sponsored research on the phylogeny of Madagascar's living Carnivora. Previously thought to represent two to four separate lineages, the island's carnivores are now known to have descended from a single species. These findings, recently published in the journal Nature, are presented in the FMNH Web site as a 4-page press release that should appeal to general readers as well as interested researchers.

2003-01-01

174

Chapelieria magna, a new species of Rubiaceae from eastern Madagascar  

PubMed Central

Abstract A new species of Chapelieria was discovered during a recent field trip to the Masoala National Park in eastern Madagascar, and is described here as Chapelieria magna Kainul., sp. nov. This species is readily distinguishable from previously described species of the genus by its quadrangular shoots, triangular-calyptrate stipules, sessile leaves, pubescent styles, and ridged fruits. It also differs in the larger number of ovules and the much larger size of leaves and fruits. PMID:25698895

Kainulainen, Kent; Razafimandimbison, Sylvain G.

2015-01-01

175

Extinction Risks and the Conservation of Madagascar's Reptiles  

PubMed Central

Background An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises. Methodology/Principal Findings Species range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas. Conclusions/Significance With a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of these arid regions to conserving the island's biodiversity. PMID:25111137

Jenkins, Richard K. B.; Tognelli, Marcelo F.; Bowles, Philip; Cox, Neil; Brown, Jason L.; Chan, Lauren; Andreone, Franco; Andriamazava, Alain; Andriantsimanarilafy, Raphali R.; Anjeriniaina, Mirana; Bora, Parfait; Brady, Lee D.; Hantalalaina, Elisoa F.; Glaw, Frank; Griffiths, Richard A.; Hilton-Taylor, Craig; Hoffmann, Michael; Katariya, Vineet; Rabibisoa, Nirhy H.; Rafanomezantsoa, Jeannot; Rakotomalala, Domoina; Rakotondravony, Hery; Rakotondrazafy, Ny A.; Ralambonirainy, Johans; Ramanamanjato, Jean-Baptiste; Randriamahazo, Herilala; Randrianantoandro, J. Christian; Randrianasolo, Harison H.; Randrianirina, Jasmin E.; Randrianizahana, Hiarinirina; Raselimanana, Achille P.; Rasolohery, Andriambolantsoa; Ratsoavina, Fanomezana M.; Raxworthy, Christopher J.; Robsomanitrandrasana, Eric; Rollande, Finoana; van Dijk, Peter P.; Yoder, Anne D.; Vences, Miguel

2014-01-01

176

Xenopsylla cheopis (Siphonaptera: Pulicidae) Susceptibility to Deltamethrin in Madagascar  

PubMed Central

The incidence of bubonic plague in Madagascar is high. This study reports the susceptibility of 32 different populations of a vector, the flea Xenopsylla cheopis (Siphonaptera: Pulicidae), to the insecticide Deltamethrin. Despite the use of Deltamethrin against fleas, plague epidemics have re-emerged in Madagascar. The majority of the study sites were located in the Malagasy highlands where most plague cases have occurred over the last 10 years. X. cheopis fleas were tested for susceptibility to Deltamethrin (0.05%): only two populations were susceptible to Deltamethrin, four populations were tolerant and 26 populations were resistant. KD50 (50% Knock-Down) and KD90 (90% Knock-Down) times were determined, and differed substantially from 9.4 to 592.4 minutes for KD50 and 10.4 min to 854.3 minutes for KD90. Susceptibility was correlated with latitude, but not with longitude, history of insecticide use nor date of sampling. Combined with the number of bubonic plague cases, our results suggest that an immediate switch to an insecticide other than Deltamethrin is required for plague vector control in Madagascar. PMID:25369291

Elissa, Nohal

2014-01-01

177

Madagascar corals reveal Pacific multidecadal modulation of rainfall since 1708  

NASA Astrophysics Data System (ADS)

The Pacific Ocean modulates Australian and North American rainfall variability on multidecadal timescales, in concert with the Pacific Decadal Oscillation (PDO). It has been suggested that Pacific decadal variability may also influence Indian Ocean surface temperature and rainfall in a far-field response, similar to the El Niño Southern Oscillation (ENSO) on interannual timescales. However, instrumental records of rainfall are too short and too sparse to confidently assess such multidecadal climatic teleconnections. Here, we present four climate archives spanning the past 300 yr from giant Madagascar corals. We decouple 20th century human deforestation effects from rainfall induced soil erosion using spectral luminescence scanning and geochemistry. The corals provide the first evidence for Pacific decadal modulation of rainfall over the Western Indian Ocean. We find that positive PDO phases are associated with increased Indian Ocean temperatures and rainfall in Eastern Madagascar, while precipitation in Southern Africa and Eastern Australia declines. Consequently, the negative PDO phase that started in 1998 should lead to reduced rainfall over Eastern Madagascar and increased precipitation in Southern Africa and Eastern Australia. We conclude that the PDO has important implications for future multidecadal variability of African rainfall, where water resource management is increasingly important under the warming climate.

Grove, C. A.; Zinke, J.; Peeters, F.; Park, W.; Scheufen, T.; Kasper, S.; Randriamanantsoa, B.; McCulloch, M. T.; Brummer, G.-J. A.

2012-03-01

178

Sarandibrinus, a new genus of Saprininae subfamily from Madagascar (Coleoptera, Histeridae) (Second contribution to the knowledge of the Histeridae of Madagascar)  

PubMed Central

Abstract Sarandibrinus araceliae, a new genus and species of the Saprininae subfamily is described from southern Madagascar. The new taxon exhibits autapomorphic characters for the Saprininae subfamily and is unusual especially for its large and deep prosternal foveae and the shape of spiculum gastrale. The description is accompanied by color habitus images, SEM micrographs, mouthparts and antenna line drawings and drawings of the male genitalia. Key to the genera of the Saprininae of Madagascar and the adjacent archipelagos is given. Hypocaccus (Baeckmanniolus) rubiciliae (Lewis, 1899) is newly reported from Madagascar and Hypocaccus (Nessus) perparvulus (Desbordes, 1916) is new to Mauritius. PMID:25147466

Lackner, Tomáš; Gomy, Yves

2014-01-01

179

A geological synthesis of the Precambrian shield in Madagascar  

USGS Publications Warehouse

Available U–Pb geochronology of the Precambrian shield of Madagascar is summarized and integrated into a synthesis of the region’s geological history. The shield is described in terms of six geodynamic domains, from northeast to southwest, the Bemarivo, Antongil–Masora, Antananarivo, Ikalamavony, Androyan–Anosyan, and Vohibory domains. Each domain is defined by distinctive suites of metaigneous rocks and metasedimentary groups, and a unique history of Archean (?2.5 Ga) and Proterozoic (?1.0 Ga, ?0.80 Ga, and ?0.55 Ga) reworking. Superimposed within and across these domains are scores of Neoproterozoic granitic stocks and batholiths as well as kilometer long zones of steeply dipping, highly strained rocks that record the effects of Gondwana’s amalgamation and shortening in latest Neoproterozoic time (0.560–0.520 Ga). The present-day shield of Madagascar is best viewed as part of the Greater Dharwar Craton, of Archean age, to which three exotic terranes were added in Proterozoic time. The domains in Madagascar representing the Greater Dharwar Craton include the Antongil–Masora domain, a fragment of the Western Dharwar of India, and the Neoarchean Antananarivo domain (with its Tsaratanana Complex) which is broadly analogous to the Eastern Dharwar of India. In its reconstructed position, the Greater Dharwar Craton consists of a central nucleus of Paleo-Mesoarchean age (>3.1 Ga), the combined Western Dharwar and Antongil–Masora domain, flanked by mostly juvenile “granite–greenstone belts” of Neoarchean age (2.70–2.56 Ga). The age of the accretionary event that formed this craton is approximately 2.5–2.45 Ga. The three domains in Madagascar exotic to the Greater Dharwar Craton are the Androyan–Anosyan, Vohibory, and Bemarivo. The basement to the Androyan–Anosyan domain is a continental terrane of Paleoproterozoic age (2.0–1.78 Ga) that was accreted to the southern margin (present-day direction) of the Greater Dharwar Craton in pre-Stratherian time (>1.6 Ga), and rejuvenated at 1.03–0.93 Ga with the creation of the Ikalamavony domain. The Vohibory domain, an oceanic terrane of Neoproterozoic age was accreted to the Androyan–Anosyan domain in Cryogenian time (?0.63–0.60 Ga). The Bemarivo domain of north Madagascar is a terrane of Cryogenian igneous rocks, with a cryptic Paleoproterozoic basement, that was accreted to the Greater Dharwar Craton in latest Ediacaran to earliest Cambrian time (0.53–0.51 Ga).

Tucker, Robert D.; Roig, J.Y.; Moine, B.; Delor, C.; Peters, S.G.

2014-01-01

180

Genome assembly and annotation of a Drosophila simulans strain from Madagascar.  

PubMed

Drosophila simulans is a close relative of the genetic model D. melanogaster. Its worldwide distribution in combination with the absence of segregating chromosomal inversions makes this species an increasingly attractive model to study the molecular signatures of adaptation in natural and experimental populations. In an effort to improve the genomic resources for D. simulans, we assembled and annotated the genome of a strain originating from Madagascar (M252), the ancestral range of D. simulans. The comparison of the M252 genome to other available D. simulans assemblies confirmed its high quality, but also highlighted genomic regions that are difficult to assemble with NGS data. The annotation of M252 provides a clear improvement with alternative splicing for 52% of the multiple-exon genes, UTRs for 70% of the genes, 225 novel genes and 781 pseudogenes being reported. We anticipate that the M252 genome will be a valuable resource for many research questions. PMID:24961367

Palmieri, Nicola; Nolte, Viola; Chen, Jun; Schlötterer, Christian

2015-03-01

181

Genome assembly and annotation of a Drosophila simulans strain from Madagascar  

PubMed Central

Drosophila simulans is a close relative of the genetic model D. melanogaster. Its worldwide distribution in combination with the absence of segregating chromosomal inversions makes this species an increasingly attractive model to study the molecular signatures of adaptation in natural and experimental populations. In an effort to improve the genomic resources for D. simulans, we assembled and annotated the genome of a strain originating from Madagascar (M252), the ancestral range of D. simulans. The comparison of the M252 genome to other available D. simulans assemblies confirmed its high quality, but also highlighted genomic regions that are difficult to assemble with NGS data. The annotation of M252 provides a clear improvement with alternative splicing for 52% of the multiple-exon genes, UTRs for 70% of the genes, 225 novel genes and 781 pseudogenes being reported. We anticipate that the M252 genome will be a valuable resource for many research questions. PMID:24961367

PALMIERI, NICOLA; NOLTE, VIOLA; CHEN, JUN; SCHLÖTTERER, CHRISTIAN

2015-01-01

182

Role of elements and physiologically active compounds in the regulation of synthesis and accumulation of indole alkaloids in Catharanthus roseus L  

Microsoft Academic Search

Effects of various elements (Co, Ni, Zn, W, Mn, Cr, B, Mo, Fe, and V), natural and synthetic auxins, cytokinins, and gibberellin on biosynthesis and accumulation of indole alkaloids was studied at increasing concentrations in the model system of Madagascar periwinkle seedlings (Catharanthus roseus L.). The main types of concentration dependences for the effect of physiologically active compounds under study

M. Ya. Lovkova; G. N. Buzuk; S. M. Sokolova; L. N. Buzuk

2005-01-01

183

The antiquity of Madagascar's grasslands and the rise of C4 grassy biomes  

E-print Network

ORIGINAL ARTICLE The antiquity of Madagascar's grasslands and the rise of C4 grassy biomes William ­ that the grasslands are an insular example of the post-Miocene spread of C4 grassy biomes world-wide. Location with species endemic to Madagascar. Plant and animal species endemic to C4 grassy biomes would not be expected

Silander Jr., John A.

184

Chow Down! Using Madagascar Hissing Cockroaches to Explore Basic Nutrition Concepts  

ERIC Educational Resources Information Center

The Madagascar hissing cockroach ("Gromphadorhina portentosa") is one of the most exciting and enjoyable animals to incorporate into your science curriculum. Madagascar hissing cockroaches (MHCs) do not bite, are easy to handle, produce little odor compared to many terrarium animals, have a fascinating social structure, are easy to breed, teach…

Wagler, Ron

2009-01-01

185

Deforestation history of the eastern rain forests of Madagascar from satellite images  

Microsoft Academic Search

Madagascar is biologically one of the richest areas on Earth, and its plants and animals are among the most endangered. Satellite images and vegetation maps based on earlier aerial photographs were used to determine the extent of eastern rain forests in Madagascar and to monitor the rate of deforestation over a 35-year period. In 1985, 3.8 million hectares of rain

G. M. Green; R. W. Sussman

1990-01-01

186

Sustainable livelihoods and forest resources in Madagascar: a multi-scale analysis using remote sensing  

Microsoft Academic Search

Madagascar, as much of sub-Saharan Africa, suffers from highly variable and unpredictable climate, and human societies, as well as the natural ecosystems upon which they depend, have evolved and adapted to cope with this to some degree since humans populated the island some 2000 years BP. In Madagascar, humans are an integral component of most landscapes and, thus, may be

Terence P. Dawson; J. Carter Ingram

2008-01-01

187

Springs and wire plants: anachronistic defences against Madagascar's extinct elephant birds  

E-print Network

vertebrates have become extinct as humans settled new lands from the Late Pleistocene to the last millennium birds (Aepyornithidae) in Madagascar. Madagascar had a very unusual fauna prior to human settlement some 2000 years ago (Burney et al. 2004). Terrestrial herbivores included elephant birds, giant lemurs

Silander Jr., John A.

188

Predicting plant diversity patterns in madagascar: understanding the effects of climate and land cover change in a biodiversity hotspot.  

PubMed

Climate and land cover change are driving a major reorganization of terrestrial biotic communities in tropical ecosystems. In an effort to understand how biodiversity patterns in the tropics will respond to individual and combined effects of these two drivers of environmental change, we use species distribution models (SDMs) calibrated for recent climate and land cover variables and projected to future scenarios to predict changes in diversity patterns in Madagascar. We collected occurrence records for 828 plant genera and 2186 plant species. We developed three scenarios, (i.e., climate only, land cover only and combined climate-land cover) based on recent and future climate and land cover variables. We used this modelling framework to investigate how the impacts of changes to climate and land cover influenced biodiversity across ecoregions and elevation bands. There were large-scale climate- and land cover-driven changes in plant biodiversity across Madagascar, including both losses and gains in diversity. The sharpest declines in biodiversity were projected for the eastern escarpment and high elevation ecosystems. Sharp declines in diversity were driven by the combined climate-land cover scenarios; however, there were subtle, region-specific differences in model outputs for each scenario, where certain regions experienced relatively higher species loss under climate or land cover only models. We strongly caution that predicted future gains in plant diversity will depend on the development and maintenance of dispersal pathways that connect current and future suitable habitats. The forecast for Madagascar's plant diversity in the face of future environmental change is worrying: regional diversity will continue to decrease in response to the combined effects of climate and land cover change, with habitats such as ericoid thickets and eastern lowland and sub-humid forests particularly vulnerable into the future. PMID:25856241

Brown, Kerry A; Parks, Katherine E; Bethell, Colin A; Johnson, Steig E; Mulligan, Mark

2015-01-01

189

[Plants regeneration from genetically transformed root and callus cultures of periwinkle Vinca minor L. and foxglove purple Digitalis purpurea L].  

PubMed

Plants regenerated from hairy roots and calluses of foxglove purple and periwinkle have been obtained. It was found that organogenesis in hairy root culture occurs spontaneously on hormone-free medium but with different efficiencies. The frequency of direct shoot formation from root cultures was up to 60% in Digitalis and 3.7% in Vinca. Addition of 1 mg/l BA, 0.1 mg/l NAA and 5% sucrose to B5 medium increased regenerative capacity of Vinca roots up to 19.1%. Regenerated plants showed morphological features typically seen in Ri-transgenic plants. They include growth and plagiotropism of the root system, increased shoot formation, changed leaf morphology and short internodes. PMID:25318175

Leshina, L G; Bulko, O V

2014-01-01

190

Lower and Middle Cenomanian ammonites from the Morondava Basin, Madagascar  

NASA Astrophysics Data System (ADS)

Kennedy, W.J., Walaszczyk, I., Gale, A.S., Dembicz, K. and Praszkier, T. 2013. Lower and Midle Cenomanian ammonites from the Morondava Basin, Madagascar. Acta Geologica Polonica, 63(4), 625-655. Warszawa. Lower and Middle Cenomanian ammonite assemblages have been collected on a bed-by-bed basis from localities at Vohipaly and Mahaboboka, Madagascar, as well as from outcrops around Berekata, all in the Morondava Basin, southwest Madagascar. These collections demonstrate the presence of the upper Lower Cenomanian Mantelliceras dixoni Zone and the lower Middle Cenomanian Cunningtoniceras inerme Zone of the north-western European standard sequence. These records indicate that the striking anomalies in the zonal assemblages of the classic divisions of the Madagascan Cenomanian are based on mixed assemblages, rather than a succession that differs radically from that elsewhere in the world. The dixoni Zone fauna is: Desmoceras cf. latidorsatum (Michelin, 1838), Pachydesmoceras kossmati Matsumoto, 1987, Forbesiceras sp., F. baylissiWright & Kennedy, 1984, F. largilliertianum (d'Orbigny, 1841), Mantelliceras cantianum Spath, 1926a, M. dixoni Spath, 1926b, M. mantelli (J. Sowerby, 1814), M. picteti Hyatt, 1903, M. saxbii (Sharpe, 1857), Sharpeiceras sp., S. falloti (Collignon, 1931), S. mocambiquense (Choffat, 1903), S. cf. florencae Spath, 1925, Acompsoceras renevieri (Sharpe, 1857), A. tenue Collignon, 1964, Calycoceras sp., Mrhiliceras lapparenti (Pervinquière, 1907), Mariella (Mariella) stolizcai (Collignon, 1964), Hypoturrilites taxyfabreae (Collignon, 1964), Turrilites scheuchzerianus Bosc, 1801, Sciponoceras cucullatum Collignon, 1964, and Sciponoceras antanimangaensis (Collignon, 1964). The presence of Calycoceras in a Lower Cenomanian association represents a precocious appearance of a genus typically Middle and Upper Cenomanian in occurrence, and matches records from Tunisia. The inerme Zone yields a more restricted assemblage: Pachydesmoceras kossmati, Forbesiceras baylissi, Acanthoceras sp. juv., Cunningtoniceras cunningtoni (Sharpe, 1855) and Hypoturrilites taxyfabreae.

Kennedy, William James; Walaszczyk, Ireneusz; Gale, Andrew S.; Dembicz, Krzysztof; Praszkier, Tomasz

2013-12-01

191

Molecular characterization of a cytokinin-inducible periwinkle protein showing sequence homology with pathogenesis-related proteins and the Bet v 1 allergen family  

Microsoft Academic Search

Cytokinin treatment of periwinkle callus cultures increased the accumulation of a protein, designated T1, in two-dimensional separated protein extracts. The first 30 NH2-terminal amino acids were determined by Edman degradation and showed significant sequence homology with intracellular pathogenesis-related (IPR) plant proteins and the Bet v 1 allergen family. The deduced amino acid sequence of cDNAs coding for T1, isolated by

Sabine Carpin; Sylvia Laffer; Françoise Schoentgen; Rudolf Valenta; Jean-Claude Chénieux; Marc Rideau; Saïd Hamdi

1998-01-01

192

Grazing of the invasive alga Codium fragile ssp. tomentosoides by the common periwinkle Littorina littorea: Effects of thallus size, age and condition  

Microsoft Academic Search

We examined the potential of herbivory by the common periwinkle Littorina littorea to limit recruitment and vegetative re-growth of the invasive green alga Codium fragile ssp. tomentosoides in a series of manipulative field experiments in tidepools on a wave-exposed rocky shore in Nova Scotia, Canada. Snails were excluded or included from circular plots (14 to 20 cm diameter) with cages to

Robert E. Scheibling; Devin A. Lyons; Catherine B. T. Sumi

2008-01-01

193

Physiological consequences of the supralittoral fringe: microhabitat temperature profiles and stress protein levels in the tropical periwinkle Cenchritis muricatus (Linneaus, 1758)  

Microsoft Academic Search

Habitat selection by marine snails is profoundly affected by variations in biotic and abiotic factors. In the supralittoral\\u000a fringe of Caribbean rocky shores, the littorinid Cenchritis muricatus endures a near-terrestrial existence through a combination of active microhabitat choice and, during dry periods, repose.\\u000a In this study, we sought to compare knobby periwinkle body size, thermal load, water loss, and stress

Michael L. JudgeMark; Mark L. Botton; Mary G. Hamilton

194

Evaluation of the joint-action toxicity of binary mixtures of heavy metals against the mangrove periwinkle Tympanotonus fuscatus var radula (L.)  

Microsoft Academic Search

The joint-action toxicity of binary mixtures of heavy metal compounds prepared in predefined ratios of 4:1, 3:2, 1:1, 2:3, and 1:4 (wt\\/wt) of Zn:Cu, Zn:Cd, and Cd:Cu, respectively, and tested against the mangrove periwinkle Tympanotonus fuscatus were carried out in laboratory bioassays. The interactions between binary mixtures showed significant departures from the action of the individual constituent metals when acting

Adebayo Akeem Otitoloju

2002-01-01

195

Predator-induced alarm responses in the common periwinkle, Littorina littorea: dependence on season, light conditions, and chemical labelling of predators  

Microsoft Academic Search

Chemically mediated alarm reactions of the common periwinkle, Littorina littorea (L.), were studied in laboratory experiments during two consecutive summers, and one intermediate autumn season. Responses\\u000a to chemical stimuli were detected as crawl-out responses, i.e. movements of snails out of the water. Snails were exposed to\\u000a extracts of injured conspecifics, extracts of the mussel Modiolus modiolus (L.), and water conditioned

H. P. Jacobsen; O. B. Stabell

1999-01-01

196

Occurrence of 210Po in periwinkle (Littorina undulata, Gray, 1839) collected from Kudankulam (Gulf of Mannar (GOM), Southeast coast of India).  

PubMed

Polonium-210 activity concentration was analysed in the whole body tissue of periwinkle Littorina undulata collected from intertidal rocky shore along Kudankulam coast. We carried out the study for a period of 12 months (2011-2012) focusing on three seasons. (210)Po was found non-uniformly distributed among the periwinkles depending on the allometry. The (210)Po accumulation showed a significant difference between seasons (p<0.05). Smaller sized winkles registered higher activity of (210)Po compared to larger ones (p<0.05). The overall activity range of (210)Po varied from 13.5 to 58.9 Bq/kg (wet). The activity of (210)Po was also quantified in seawater and intertidal sediments to calculate the biological concentration factor (BCF) and radiation dose rate. The dose rate to the winkles was performed using ERICA Assessment Tool and it was within the prescribed limit. The intake of (210)Po through periwinkles delivered an effective dose in the range of 2.2-9.6 ?Sv/y to human beings. PMID:23871576

Sunith Shine, S R; Feroz Khan, M; Godwin Wesley, S

2013-10-15

197

Proterozoic tectonostratigraphy and paleogeography of central Madagascar derived from detrital zircon U-Pb age populations  

USGS Publications Warehouse

Detrital zircon U-Pb ages determined by SHRIMP distinguish two clastic sequences among Proterozoic metasedimentary rocks from central Madagascar. The Itremo Group is older: zircon data, stromatolite characteristics, and carbon isotope data all point to a depositional age around 1500-1700 Ma. The Molo Group is younger, deposited between ???620 Ma (the age of the youngest zircon) and ???560 Ma (the age of metamorphic overgrowths on detrital cores). Geochronologic provenance analysis of the Itremo Group points to sources in East Africa as well as local sources in central and southern Madagascar but provides no evidence for a detrital contribution from northern and eastern Madagascar nor from southern India. Detrital zircon and sedimentologic similarities between rocks of the Itremo Group and the Zambian Muva Supergroup suggest a lithostratigraphic correlation between the two. The Molo Group has a strong 1000-1100 Ma detrital signature that also indicates an east African provenance and suggests a Neoproterozoic geographic connection with Sri Lanka but shows no indication of input from the Dharwar craton and eastern Madagascar. Central Madagascar was probably juxtaposed with the Tanzanian craton in the Paleo- and Mesoproterozoic, whereas northern and eastern Madagascar were connected to India. Internal assembly of Madagascar postdates Neoproterozoic Molo Group sedimentation and is likely to have occurred at about 560 Ma. ?? 2004 by The University of Chicago. All rights reserved.

Cox, R.; Coleman, D.S.; Chokel, C.B.; DeOreo, S.B.; Wooden, J.L.; Collins, A.S.; De Waele, B.; Kroner, A.

2004-01-01

198

Defining and explaining tropical deforestation: shifting cultivation and population growth in colonial Madagascar (1896-1940).  

PubMed

The case study of deforestation in Madagascar demonstrated how deforestation is a complex phenomenon that reflects interconnections between land-based resources, human groups, and global political economy; specifically, there is a link between changing land use practices affecting shifting cultivation and tropical deforestation. The general development model of exponential population growth and shifting cultivation causing deforestation and environmental degradation is too simplified, places undue blame on the victims, and isolates shifting cultivation practices from the reality of land use patterns in specific places at specific times. Problematic also is the way definition, delimitation, and discussion of environmental problems shapes possible solutions. This analysis suggests a theoretical view that links reconstructed regional geography with political ecology. The assertion is that deforestation is historically based on multiple social processes within Madagascar. Land use practices and resource access decisions during the colonial period affected land management and degradation. The colonial state policy played a role in the destruction of tropical flora by fire, shifting cultivation, and grazing, and the responses of Europeans and Malagasys. Context and multiplicity of motivations and practices were key. A review was presented of reconstructed regional geography and political ecology and global tropical deforestation. The description of the political economy of deforestation during colonial times focused on the movement of population into the forests after 1896 and French annexation. Famine resulted. Shifting cultivation laws were passed between 1881 and 1913, due to the desire for rational forest resource management. Ecologically and socially these rules were difficult to enforce; there were resistance due to the threat of the elimination of subsistence living for wage work. Destructive logging practices and forest product extraction after 1921 are described. During 1900-1941, population was below or at replacement level, but the government still blamed Malagasys. Shifting cultivation meant different things to the subsistence farmers, the state, and international agencies. Denial of context promotes an ideology of repression, fuels fear and prejudice, and promotes the wrong solutions. PMID:12318844

Jarosz, L

1993-10-01

199

Madagascar: A continental fragment of the paleo-super Dharwar craton of India  

NASA Astrophysics Data System (ADS)

The morphological kinship of Madagascar to its immediate neighbors on the west (African continent) and east (Indian subcontinent) during the Early and middle Cretaceous has been debated for the past two decades on the basis of available geologic, tectonic, and paleomagnetic information. Most of the paleoreconstructions of Madagascar have shown its attachment to the east African continent. We present magnetic satelite and gravity data, and morphological, geophysical, and geotectonic similarities to hypothesize that in the period before the breakup of Gondwana, Madagascar was a continental fragment of the paleo-super Dharwar craton of India.

Agrawal, P. K.; Pandey, O. P.; Negi, J. G.

1992-06-01

200

Statut familial et inégalités face à la scolarisation à Madagascar  

NASA Astrophysics Data System (ADS)

The impact of family status in Madagascar on inequalities in schooling - In this article, in the context of generalised access to primary education and parity between girls and boys, we analyse data from the Demographic and Health Survey (DHS) 2009 in Madagascar to examine inequalities in schooling related to children's status in the family. The results confirm the protective benefit for children of living with their biological parents. Fostered children are disadvantaged, especially and increasingly so depending on whether they live with an uncle or aunt, with a distant relative or a non-relative. Conversely, children who reside in the home of a brother or sister are not disadvantaged, a result which reflects the role of elder children in family education strategies. Grandparents play a moderately positive role in schooling. The death of the father is an important factor in dropping out. Finally, children whose parent or parents are not household heads are disadvantaged in terms of schooling compared to children of household heads.

Delaunay, Valérie; Gastineau, Bénédicte; Andriamaro, Frédérique

2013-12-01

201

Austronesian genetic signature in East African Madagascar and Polynesia.  

PubMed

The dispersal of the Austronesian language family from Southeast Asia represents the last major diaspora leading to the peopling of Oceania to the East and the Indian Ocean to the West. Several theories have been proposed to explain the current locations, and the linguistic and cultural diversity of Austronesian populations. However, the existing data do not support unequivocally any given migrational scenario. In the current study, the genetic profile of 15 autosomal STR loci is reported for the first time for two populations from opposite poles of the Austronesian range, Madagascar at the West and Tonga to the East. These collections are also compared to geographically targeted reference populations of Austronesian descent in order to investigate their current relationships and potential source population(s) within Southeast Asia. Our results indicate that while Madagascar derives 66.3% of its genetic makeup from Africa, a clear connection between the East African island and Southeast Asia can be discerned. The data suggest that although geographic location has influenced the phylogenetic relationships between Austronesian populations, a genetic connection that binds them beyond geographical divides is apparent. PMID:18080086

Regueiro, M; Mirabal, S; Lacau, H; Caeiro, J L; Garcia-Bertrand, R L; Herrera, R J

2008-01-01

202

Mangrove forest distributions and dynamics in Madagascar (1975-2005)  

USGS Publications Warehouse

Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of ?? one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ???2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km 2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%). ?? 2008 by MDPI.

Giri, C.; Muhlhausen, J.

2008-01-01

203

Mangrove Forest Distributions and Dynamics in Madagascar (1975–2005)  

PubMed Central

Mangrove forests of Madagascar are declining, albeit at a much slower rate than the global average. The forests are declining due to conversion to other land uses and forest degradation. However, accurate and reliable information on their present distribution and their rates, causes, and consequences of change have not been available. Earlier studies used remotely sensed data to map and, in some cases, to monitor mangrove forests at a local scale. Nonetheless, a comprehensive national assessment and synthesis was lacking. We interpreted time-series satellite data of 1975, 1990, 2000, and 2005 using a hybrid supervised and unsupervised classification approach. Landsat data were geometrically corrected to an accuracy of ± one-half pixel, an accuracy necessary for change analysis. We used a postclassification change detection approach. Our results showed that Madagascar lost 7% of mangrove forests from 1975 to 2005, to a present extent of ?2,797 km2. Deforestation rates and causes varied both spatially and temporally. The forests increased by 5.6% (212 km2) from 1975 to 1990, decreased by 14.3% (455 km2) from 1990 to 2000, and decreased by 2.6% (73 km2) from 2000 to 2005. Similarly, major changes occurred in Bombekota Bay, Mahajamba Bay, the coast of Ambanja, the Tsiribihina River, and Cap St Vincent. The main factors responsible for mangrove deforestation include conversion to agriculture (35%), logging (16%), conversion to aquaculture (3%), and urban development (1%).

Giri, Chandra; Muhlhausen, Joseph

2008-01-01

204

Mountain Refugia Play a Role in Soil Arthropod Speciation on Madagascar: A Case Study of the Endemic Giant Fire-Millipede Genus Aphistogoniulus  

PubMed Central

To elucidate the speciation mechanisms prevalent within hotspots of biodiversity, and the evolutionary processes behind the rise of their species-rich and endemic biota, we investigated the phylogeny of the giant fire-millipede genus Aphistogoniulus Silvestri, 1897, a Malagasy endemic. This study is the first comprehensive (molecular and morphological) phylogenetic study focusing on millipede (class Diplopoda) speciation on Madagascar. The morphological analysis is based on 35 morphological characters and incorporates ten described as well as two newly described species (A. rubrodorsalis n. sp. and A. jeekeli n. sp.) of Aphistogoniulus. The molecular analysis is based on both mitochondrial (COI and 16S), and nuclear genes (complete 18S rDNA), together comprised of 3031 base pairs, which were successfully sequenced for 31 individual specimens and eight species of Aphistogoniulus. In addition to the null-model (speciation by distance), two diversification models, mountain refugia and ecotone shift, were discovered to play a role in the speciation of soil arthropods on Madagascar. Mountain refugia were important in the speciation of the A. cowani clade, with three species occurring in the Andringitra and Ranomafana Mountains in the southeast (A. cowani), the Ambohijanahary and Ambohitantely Mountains in the mid-west (A. sanguineus), and the Marojejy Mountain in the northeast (A. rubrodorsalis n. sp.). An ecotone shift from the eastern rainforest to the unique subarid spiny forest of Mahavelo was discovered in the A. vampyrus - A. aridus species-pair. In the monophyletic A. diabolicus clade, evidence for divergent evolution of sexual morphology was detected: species with greatly enlarged gonopods are sister-taxa to species with normal sized gonopods. Among the large-bodied Spirobolida genera of Madagascar, Colossobolus and Sanguinobolus were found to be close sister-genera to Aphistogoniulus. Forest destruction has caused forest corridors between populations to disappear, which might limit the possible resolution of biogeographic analyses on Madagascar. PMID:22162998

Wesener, Thomas; Raupach, Michael J.; Decker, Peter

2011-01-01

205

Phylogeographic analysis of the true lemurs (genus Eulemur) underlines the role of river catchments for the evolution of micro-endemism in Madagascar  

PubMed Central

Introduction Due to its remarkable species diversity and micro-endemism, Madagascar has recently been suggested to serve as a biogeographic model region. However, hypothesis-based tests of various diversification mechanisms that have been proposed for the evolution of the island’s micro-endemic lineages are still limited. Here, we test the fit of several diversification hypotheses with new data on the broadly distributed genus Eulemur using coalescent-based phylogeographic analyses. Results Time-calibrated species tree analyses and population genetic clustering resolved the previously polytomic species relationships among eulemurs. The most recent common ancestor of eulemurs was estimated to have lived about 4.45 million years ago (mya). Divergence date estimates furthermore suggested a very recent diversification among the members of the “brown lemur complex”, i.e. former subspecies of E. fulvus, during the Pleistocene (0.33-1.43 mya). Phylogeographic model comparisons of past migration rates showed significant levels of gene flow between lineages of neighboring river catchments as well as between eastern and western populations of the redfronted lemur (E. rufifrons). Conclusions Together, our results are concordant with the centers of endemism hypothesis (Wilmé et al. 2006, Science 312:1063–1065), highlight the importance of river catchments for the evolution of Madagascar’s micro-endemic biota, and they underline the usefulness of testing diversification mechanisms using coalescent-based phylogeographic methods. PMID:24228694

2013-01-01

206

A homolog of tocopherol C-methyltransferases catalyzes N-methylation in anticancer alkaloid biosynthesis  

E-print Network

Madagascar periwinkle (Catharanthus roseus) is the sole source of the anticancer drugs vinblastine and vincristine, bisindole alkaloids derived from the dimerization of the terpenoid indole alkaloids vindoline and ...

Liscombe, David K.

207

Madagascar Flatidae (Hemiptera, Fulgoromorpha): state-of-the-art and research challenges  

PubMed Central

Abstract The paper provides a historical review of the research on Flatidae in Madagascar and indicates future prospects. While the first two species of Madagascar Flatidae were described by Guérin-Méneville (1844), it was Signoret (1860) who made the first real attempt to enhance our knowledge of the Hemiptera fauna of Madagascar by describing several additional species. Over the following century and a half, several investigators have turned their attention to this group of insects, with the final number of species recorded for the island reaching 79. Despite this long history of research, it is evident that much still remains to be done. Detailed taxonomic research will allow the natural history of Madagascar and changes in the biological diversity of its endemic ecosystems to be better understood. This paper should be considered as an introduction to a complex study on the systematics and phylogeny of worldwide Flatidae planthoppers. PMID:24039526

?wierczewski, Dariusz; Stroi?ski, Adam

2013-01-01

208

STUDY OF LAND USE ISSUES CHARACTERIZING THE AMBALAVAO-ANDRINGITRA REGION OF MADAGASCAR  

EPA Science Inventory

EPA Identifier: GF9500572 Title: Study of Land Use Issues Characterizing the Ambalavao-Andringitra Region of Madagascar Fellow (Principal Investigator): Christian Arthur Kull Institution: University of Colorado EPA Grant Representati...

209

Redescription of Trogoderma fasciolata Fairmaire, 1897, comb. rev. from Madagascar (Coleoptera: Dermestidae, Megatomini).  

PubMed

Trogoderma fasciolata Fairmaire, 1897, comb. rev. is redescribed, illustrated and restored to the genus Trogoderma Dejean, 1821 from Aethriostoma Motschulsky, 1858. A key to the known Trogoderma species from Madagascar is presented. PMID:25781265

Kadej, Marcin; Háva, Ji?í

2015-01-01

210

Comprehensive Red List Assessment Reveals Exceptionally High Extinction Risk to Madagascar Palms  

PubMed Central

The establishment of baseline IUCN Red List assessments for plants is a crucial step in conservation planning. Nowhere is this more important than in biodiversity hotspots that are subject to significant anthropogenic pressures, such as Madagascar. Here, all Madagascar palm species are assessed using the IUCN Red List categories and criteria, version 3.1. Our results indicate that 83% of the 192 endemic species are threatened, nearly four times the proportion estimated for plants globally and exceeding estimates for all other comprehensively evaluated plant groups in Madagascar. Compared with a previous assessment in 1995, the number of Endangered and Critically Endangered species has substantially increased, due to the discovery of 28 new species since 1995, most of which are highly threatened. The conservation status of most species included in both the 1995 and the current assessments has not changed. Where change occurred, more species have moved to lower threat categories than to higher categories, because of improved knowledge of species and their distributions, rather than a decrease in extinction risk. However, some cases of genuine deterioration in conservation status were also identified. Palms in Madagascar are primarily threatened by habitat loss due to agriculture and biological resource use through direct exploitation or collateral damage. The recent extension of Madagascar’s protected area network is highly beneficial for palms, substantially increasing the number of threatened species populations included within reserves. Notably, three of the eight most important protected areas for palms are newly designated. However, 28 threatened and data deficient species are not protected by the expanded network, including some Critically Endangered species. Moreover, many species occurring in protected areas are still threatened, indicating that threatening processes persist even in reserves. Definitive implementation of the new protected areas combined with local community engagement are essential for the survival of Madagascar’s palms. PMID:25075612

Rakotoarinivo, Mijoro; Dransfield, John; Bachman, Steven P.; Moat, Justin; Baker, William J.

2014-01-01

211

Distribution, status, and conservation of radiated tortoises ( Geochelone radiata) in Madagascar  

Microsoft Academic Search

The radiated tortoise, Geochelone radiata, one of Madagascar’s four endemic tortoises, occupies a narrow band of xeric spiny forest along the island’s southwest coast. Traditionally avoided by indigenous tribes, these tortoises are now routinely harvested for food. An accurate assessment of human exploitation remains problematic, however, hindered by limited, dated statistics available on tortoise populations. To update the radiated tortoise’s

Thomas E. J. Leuteritz; Trip Lamb; Jean Claude Limberaza

2005-01-01

212

THE FOOD HABITS OF THE BARN OWL TYTO ALBA AT THREE SITES ON MADAGASCAR  

Microsoft Academic Search

Goodman, S. M., Langrand, O. & Raxworthy, C. J. 1993. The food habits of the Barn Owl Tyro alba at three sites on Madagascar. Ostrich 64:160-171.Regurgitated food remains of the Barn Owl Tyro alba were collected within the rain forest of the Eastern Region of Madagascar (Andasibe and Manombo) and in the sub-arid thorn scrub of the Western Region (Beza

Steven M. Goodman; Olivier Langrand; Christopher J. Raxworthy

1993-01-01

213

An economic analysis of deforestation in Madagascar in the 1990s  

Microsoft Academic Search

Madagascar is well-known among conservationists for both its unique forest ecosystems and its alarmingly high rates of deforestation. This paper studies the factors driving deforestation in Madagascar using a nation-wide data set of commune-level variables. The analysis suggests that higher population and fertility rates were associated with higher deforestation in the moist forest region in the 1990s. Deforestation was lower

Christine Moser

2008-01-01

214

A new perspective on the significance of the Ranotsara shear zone in Madagascar  

Microsoft Academic Search

The Ranotsara shear zone in Madagascar has been considered in previous studies to be a >350-km-long, intracrustal strike-slip\\u000a shear zone of Precambrian\\/Cambrian age. Because of its oblique strike to the east and west coast of Madagascar, the Ranotsara\\u000a shear zone has been correlated with shear zones in southern India and eastern Africa in Gondwana reconstructions. Our assessment\\u000a using remote sensing

Guido Schreurs; Jörg Giese; Alfons Berger; Edwin Gnos

2010-01-01

215

SUBORDINATE MALES SIRE OFFSPRING IN MADAGASCAR FISH-EAGLE ( HALIAEETUS VOC1FEROES) POLYANDROUS BREEDING GROUPS  

Microsoft Academic Search

ABSrRACT.--The island endemic Madagascar Fish-Eagle (Haliaeetus vociferoides) is one of the most en- dangered birds of prey. Certain populations in west-central Madagascar sometimes exhibit a third, and sotnetimes a fourth, adult involved in breeding activities at a nest. We applied DNA fingerprinting to asscss relatedness among 17 individuals at four nests. In all nests with young, a subordinate rather than

RUTH E. TINGAY; RICHARD T. WATSON

2002-01-01

216

U-Pb zircon geochronology and geochemistry of Late Jurassic basalts in Maevatanana, Madagascar: Implications for the timing of separation of Madagascar from Africa  

NASA Astrophysics Data System (ADS)

Magmatic zircon ages for the Maevatanana basalts in Madagascar indicate that Madagascar separated from Africa at 149.8 ± 2.1 Ma. Rocks produced by this basaltic magmatism associated with rifting are characterized by low SiO2 (49.6-50.3 wt.%), high total FeO (>13.9 wt.%), TiO2 (>3.7 wt.%), and P2O5 (>0.5 wt.%), and extremely high Na2O/K2O (3.08-3.27). Geochemical variations can be ascribed to significant fractional crystallization of clinopyroxene and plagioclase. The mineralogical and geochemical characteristics of the Maevatanana basalts suggest affinities with calc-alkaline basalt. Additionally the basalts have distinct ocean-island-basalt-like geochemical features that may be related to the Marion plume. We speculate that the Maevatanana basalts are the product of the Marion mantle plume related to separation of Madagascar from Africa in the Late Jurassic.

Yang, Xi-An; Chen, Yu-Chuan; Hou, Ke-Jun; Liu, Shan-Bao; Liu, Jia-Jun

2014-12-01

217

Spatial and temporal arrival patterns of Madagascar's vertebrate fauna explained by distance, ocean currents, and ancestor type  

PubMed Central

How, when, and from where Madagascar's vertebrates arrived on the island is poorly known, and a comprehensive explanation for the distribution of its organisms has yet to emerge. We begin to break that impasse by analyzing vertebrate arrival patterns implied by currently existing taxa. For each of 81 clades, we compiled arrival date, source, and ancestor type (obligate freshwater, terrestrial, facultative swimmer, or volant). We analyzed changes in arrival rates, with and without adjusting for clade extinction. Probability of successful transoceanic dispersal is negatively correlated with distance traveled and influenced by ocean currents and ancestor type. Obligate rafters show a decrease in probability of successful transoceanic dispersal from the Paleocene onward, reaching the lowest levels after the mid-Miocene. This finding is consistent with a paleoceanographic model [Ali JR, Huber M (2010) Nature 463:653–656] that predicts Early Cenozoic surface currents periodically conducive to rafting or swimming from Africa, followed by a reconfiguration to present-day flow 15–20 million years ago that significantly diminished the ability for transoceanic dispersal to Madagascar from the adjacent mainland. PMID:22431643

Samonds, Karen E.; Godfrey, Laurie R.; Ali, Jason R.; Goodman, Steven M.; Vences, Miguel; Sutherland, Michael R.; Irwin, Mitchell T.; Krause, David W.

2012-01-01

218

Cardenolides of Leptadenia madagascariensis from the Madagascar dry forest.  

PubMed

Investigation of the endemic Madagascar plant Leptadenia madagascariensis Decne. (Apocynaceae) for antiproliferative activity against the A2780 ovarian cancer cell line led to the isolation of the four new cardenolides 1-4. The structure elucidations of these compounds were based on analyzes of their 1D and 2D NMR spectra and mass spectrometric data. The cardenolides were strongly antiproliferative to the A2780 ovarian cancer cell line, with IC(50) values of 0.18, 0.21, 0.17, and 0.29?M line, and to the H460 human lung cancer cell line, with IC(50) values of 0.16, 0.68, 0.37, and 0.48?M, respectively. PMID:21159516

Pan, Ende; Harinantenaina, Liva; Brodie, Peggy J; Callmander, Martin; Rakotonandrasana, Stephan; Rakotobe, Etienne; Rasamison, Vincent E; Tendyke, Karen; Shen, Yongchun; Suh, Edward M; Kingston, David G I

2011-01-01

219

Cardenolides of Leptadenia madagascariensis from the Madagascar dry forest†  

PubMed Central

Investigation of the endemic Madagascar plant Leptadenia madagascariensis Decne. (Apocynaceae) for antiproliferative activity against the A2780 ovarian cancer cell line led to the isolation of the four new cardenolides 1–4. The structure elucidations of these compounds were based on analyses of their 1D and 2D NMR spectra and mass spectrometric data. The cardenolides were strongly antiproliferative to the A2780 ovarian cancer cell line, with IC50 values of 0.18, 0.21, 0.17 and 0.29 ?M line, and to the H460 human lung cancer cell line, with IC50 values of 0.16, 0.68, 0.37 and 0.48 ?M respectively. PMID:21159516

Pan, Ende; Harinantenaina, Liva; Brodie, Peggy J.; Callmander, Martin; Rakotonandrasana, Stephan; Rakotobe, Etienne; Rasamison, Vincent E.; TenDyke, Karen; Shen, Yongchun; Suh, Edward M.; Kingston, David G. I.

2010-01-01

220

Checklist of Fishes from Madagascar Reef, Campeche Bank, México  

PubMed Central

Abstract This study presents the first list of fish species from Madagascar Reef, Campeche Bank, Gulf of México. Field surveys and literature review identified 54 species belonging to 8 orders, 30 families and 43 genera, comprising both conspicuous and cryptic fishes. Species richness was lower at this reef site compared to reefs in the Mexican Caribbean, Veracruz or Tuxpan, but was similar to other reefs in the same region. Species composition was a mixture of species present in all the reef systems of the Mexican Atlantic. Hypoplectrus ecosur was recorded here for the first time in the Gulf of Mexico, Mycteroperca microlepis, Equetus lanceolatus and Chaetodipterus faber were new records for the reefs of the Campeche Bank, Elacatinus xanthiprora was recorded for the second time in Mexico and expanded its known distribution westwards from Alacranes Reef and Sanopus reticulatus, endemic of the Yucatan state, was recorded here for the first time on a reef. PMID:24891834

2014-01-01

221

Antiproliferative cardenolides from Pentopetia androsaemifolia from the Madagascar rain forest†  

PubMed Central

Plant natural products have historically been very important to drug discovery and development, particularly in the anticancer field. This is illustrated by a discussion of the structures and activities of camptothecin and its analogues, paclitaxel (Taxol®), the vinca alkaloids vinblastine and vincristine, and podophyllotoxin and its analogues. A description of the isolation of one new and three known cardenolides from the Madagascar plant Pentopetia androsaemifolia is then provided as an example of this approach to drug discovery. The paper concludes with a brief discussion of betulinic acid, an old compound which is being developed into an anticancer and anti-HIV agent, and ipomoeassin F, an interesting antiproliferative compound isolated from a plant collected in Suriname. PMID:21046977

Adou, Eba; Miller, James S; Ratovoson, Fidisoa; Birkinshaw, Chris; Andriantsiferana, Rabodo; Rasamison, Vincent E; Kingston, David G I

2010-01-01

222

New species of Uropodina from Madagascar (Acari: Mesostigmata).  

PubMed

Seven new species and one new genus of Uropodina are described from Madagascar. The third Afrotropical species of Polyaspis is described (Polyapis (Polyaspis) madagascarensis sp. nov.), with a key to the Afrotropical species of the genus. The first species of Dinychus from the Afrotropical region is described, as Dinychus lepus sp. nov.. An unusual new species of Trichouropoda species is described as Trichouropoda madagascarica sp. nov.. A new genus (Malagana gen. nov.) is described, with type species Malagana rotunda sp. nov.. The genus Pulchellaobovella is recorded from the Afrotropical Region for the first time, on the basis of Pulchellaobovella madagascarica sp. nov., with nomenclatural notes on the genera Pulchellaobovella and Janetiella. Uroobovella graeca Kontschán, 2010 is moved into the genus Pulchellaobovella, as Pulchellaobovella graeca (Kontschán, 2010b) comb. nov. Two new species of Rotundabaloghia (Circobaloghia) are described, Rotundabaloghia (Circobaloghia) ermilovi sp. nov. and Rotundabaloghia (Circobaloghia) kaydani sp. nov. PMID:25543586

Kontschán, Jen?; Starý, Josef

2014-01-01

223

Preparer une firme-reseau dans le transport routier des hydrocarbures le cas de TOTAL Madagascar  

NASA Astrophysics Data System (ADS)

In a dynamic context, a network firm is more and more suggested in scientific writings as a prevalent strategy to develop several firms in subcontracting link in order to satisfy the needs of their customers asking for products which are complex to manufacture. However, due to lack of sufficient preparation, most of network organizations fail. That's why it seems legitimate to explore an avenue of research on the preparation step of a network firm. How a third intermediary can develop and try out a change process in order to stimulate the commitment of films to organize themselves in network? This study is developed inside the framework of an intervention-research applied to the case of the oil distribution company TOTAL Madagascar. 71 weeks of intervention actions carried out with 27 subcontracting firms of hydrocarbon road transport located to Antananarivo are recorded within this framework. One of the critical elements in the oil distribution in Madagascar is the scarcity of the subcontracting firms of hydrocarbon road transport which are able to meet the required quality criterions. A lack of management standards observed in several small and medium enterprises of hydrocarbon road transport, a growth of the number of tankers accidents, and an insufficiency of individual resources to develop competences constitute the main reasons which explain this scarcity. By this way, a preparation step of a network firm was developed in order to increase the management competences of the subcontracting firms of hydrocarbon road transport, and to develop their capacity of collective learning. This step comes from the evolutionary perspective which consists in elaborating and implementing uprooting, movement and rooting activities related to a change implementation model taking reactions of the participating enterprises into consideration, through a change understanding process from objection to exploration until engagement. The realization of theses activities had been allowed: 44 managers of 27 participating firms to be trained, certified and sensitized with the network firm practice, 78% of the participating firms to be enthusiastic to pass to the creation of a network firm, and the enterprise pivot TOTAL Madagascar to record a significant diminution of the number of tankers accidents which is passed from 10 (77% of the total number of the tankers accidents) at the beginning of the process in 2003 to 5 (36%) at the end of this process in 2005 and to 3 (27%) in 2007. These tangible and positive results seem to prove the commitment of firms participating in the preparation step of the network firm. In this way, it is appropriate to put the hypothesis according to the experience done within the framework of this study that could be considered as a learning trajectory type of the preparation step which efficiently stimulates the intention of the participating firms to be organized in network. This present case, through these results, strengthens the consideration according to the success of the network firm which depends in the efficiency of the change process related to its preparation. Thus, a main scientific contribution of this present step rely on its originality which is the integration of two change models (implementation and understanding) inside the same research conceptual framework. In a managerial side, the essential of this step may be transferable to the other contexts which look upon the determinant role of the researcher acting as a change co-leader. That shows the utility of this step within the framework of a doctorate applied in administration. Keywords: Subcontracting -- Change -- Network firm -- Hydrocarbon Road Transport -- Small and Medium Enterprises

Razakamanifidiny, Patrick Dany

2009-12-01

224

Global warming and extinction risks for amphibians in Madagascar, an Franco Andreone, Museo Regionale di Scienze Naturali and Amphibian Specialist Group /  

E-print Network

Global warming and extinction risks for amphibians in Madagascar, an overview Franco Andreone, Museo Regionale di Scienze Naturali and Amphibian Specialist Group / Madagascar, Via G. Giolitti, 36, I.andreone@gmail.com The amphibians of Madagascar represent one of the most extraordinary biodiversity off- shots, with around 240

Andreone, Franco

225

23. Le contexte juridique des politiques foncires et de dcentralisation pour la gestion des ressources naturelles renouvelables (Approche compare Madagascar/Niger)  

E-print Network

ressources naturelles renouvelables (Approche comparée Madagascar/Niger) Sigrid AUBERT, Abdou TCHOUSSO, Jules RAZAFIARIJAONA Résumé Au Niger comme à Madagascar, la gestion décentralisée des ressources naturelles ne peut, tant au Niger qu'à Madagascar. Les ressources naturelles renouvelables s'inscrivent dans des espaces

Boyer, Edmond

226

High resolution regional soil carbon mapping in Madagascar : towards easy to update maps  

NASA Astrophysics Data System (ADS)

The soil organic carbon plays an important role in climate change regulation through carbon emissions and sequestration due to land use changes, notably tropical deforestation. Monitoring soil carbon emissions from shifting-cultivation requires to evaluate the amount of carbon stored at plot scale with a sufficient level of accuracy to be able to detect changes. The objective of this work was to map soil carbon stocks (30 cm and 100 cm depths) for different land use at regional scale using high resolution satellite dataset. The Andohahela National Parc and its surroundings (South-Est Madagascar) - a region with the largest deforestation rate in the country - was selected as a pilot area for the development of the methodology. A three steps approach was set up: (i) carbon inventory using mid infra-red spectroscopy and stock calculation, (ii) spatial data processing and (iii) modeling and mapping. Soil spectroscopy was successfully used for measuring organic carbon in this region. The results show that Random Forest was the inference model that produced the best estimates on calibration and validation datasets. By using a simple and robust method, we estimated uncertainty levels of of 35% and 43% for 30-cm and 100-cm carbon maps respectively. The approach developed in this study was based on open data and open source software that can be easily replicated to other regions and for other time periods using updated satellite images.

Grinand, Clovis; Dessay, Nadine; Razafimbelo, Tantely; Razakamanarivo, Herintsitoaina; Albrecht, Alain; Vaudry, Romuald; Tiberghien, Matthieu; Rasamoelina, Maminiaina; Bernoux, Martial

2013-04-01

227

Elaphoglossum nidusoides (Dryopteridaceae), a New Species of Fern from Madagascar with an Unusual Phylogenetic Position in the  

E-print Network

Elaphoglossum nidusoides (Dryopteridaceae), a New Species of Fern from Madagascar with an Unusual.S.A. 4 Author for correspondence (rouhan@mnhn.fr) Communicating Editor: Mark P. Simmons ABSTRACT. A fern by the succulent fronds. KEYWORDS: Elaphoglossum, fern, Madagascar, new species, phylogeny, Squamipedia

228

Education and Training in Madagascar: Toward a Policy Agenda for Economic Growth and Poverty Reduction. A World Bank Country Study.  

ERIC Educational Resources Information Center

Madagascar is a poor, primarily rural country in which three-quarters of the population has subsisted below the poverty line for at least two decades. In view of the important role of education in the government's poverty reduction agenda, this report documents the current status of educational development in Madagascar and the key constraints on…

World Bank, Washington, DC.

229

Presence of the amphibian chytrid fungus Batrachochytrium dendrobatidis in native amphibians exported from Madagascar.  

PubMed

The emerging infectious disease chytridiomycosis is driven by the spread of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd), a highly virulent pathogen threatening global amphibian biodiversity. Although pandemic in distribution, previous intensive field surveys have failed to detect Bd in Madagascar, a biodiversity hotspot home to hundreds of endemic amphibian species. Due to the presence of Bd in nearby continental Africa and the ecological crisis that can be expected following establishment in Madagascar, enhanced surveillance is imperative. I sampled 565 amphibians commercially exported from Madagascar for the presence of Bd upon importation to the USA, both to assist early detection efforts and demonstrate the conservation potential of wildlife trade disease surveillance. Bd was detected in three animals via quantitative PCR: a single Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. This is the first time Bd has been confirmed in amphibians from Madagascar and presents an urgent call to action. Our early identification of pathogen presence prior to widespread infection provides the necessary tools and encouragement to catalyze a swift, targeted response to isolate and eradicate Bd from Madagascar. If implemented before establishment occurs, an otherwise likely catastrophic decline in amphibian biodiversity may be prevented. PMID:24599336

Kolby, Jonathan E

2014-01-01

230

Detection in and circulation of Bluetongue virus among domestic ruminants in Madagascar.  

PubMed

So far, no published data was available concerning the circulation of Bluetongue virus (BTV) in Madagascar. During a survey on Rift Valley Fever, we were able to detect a virus belonging to BTV. Therefore, we conducted a study aiming at characterizing molecularly the BTV isolated and assess the importance of circulation of BTV in Madagascar. A total of 4393 sera from ruminants selected randomly by stratification and sampled in 30 districts of Madagascar were tested for BTV. Moreover, 175 cattle were followed during 11 months. Phylogenetic analyses were performed from virus isolated from unfed pools of mosquitoes. Overall, the estimated mean seroprevalence of infection at the national level was 95.9% (95% CI: [95.2-96.5]) in cattle and 83.7% (95% CI: [81.4-85.9]) in small ruminants. Estimation of incidence rate was 54 per 100 cattle-years assuming that the incidence rate is constant all year along. Phylogenetic analyses revealed that BTV detected belong to serotype 2. In conclusion, our results showed that BTV is endemic in Madagascar and highly prevalent among cattle. In our study we did not work on the vector involved in transmission of BTV in cattle. Thus, research should be conducted to better describe epidemiology of BTV in Madagascar including vectors and assess economic impact of the disease associated to BTV infections. PMID:25736861

Andriamandimby, Soa Fy; Viarouge, Cyril; Ravalohery, Jean-Pierre; Reynes, Jean-Marc; Sailleau, Corinne; Tantely, Michael Luciano; Elissa, Nohal; Cardinale, Eric; Sall, Amadou Alpha; Zientara, Stephan; Heraud, Jean-Michel

2015-04-17

231

Forecasting deforestation and carbon emissions in tropical developing countries facing demographic expansion: a case study in Madagascar  

PubMed Central

Anthropogenic deforestation in tropical countries is responsible for a significant part of global carbon dioxide emissions in the atmosphere. To plan efficient climate change mitigation programs (such as REDD+, Reducing Emissions from Deforestation and forest Degradation), reliable forecasts of deforestation and carbon dioxide emissions are necessary. Although population density has been recognized as a key factor in tropical deforestation, current methods of prediction do not allow the population explosion that is occurring in many tropical developing countries to be taken into account. Here, we propose an innovative approach using novel computational and statistical tools, including R/GRASS scripts and the new phcfM R package, to model the intensity and location of deforestation including the effect of population density. We used the model to forecast anthropogenic deforestation and carbon dioxide emissions in five large study areas in the humid and spiny-dry forests of Madagascar. Using our approach, we were able to demonstrate that the current rapid population growth in Madagascar (+3.39% per year) will significantly increase the intensity of deforestation by 2030 (up to +1.17% per year in densely populated areas). We estimated the carbon dioxide emissions associated with the loss of aboveground biomass to be of 2.24 and 0.26 tons per hectare and per year in the humid and spiny-dry forest, respectively. Our models showed better predictive ability than previous deforestation models (the figure of merit ranged from 10 to 23). We recommend this approach to reduce the uncertainty associated with deforestation forecasts. We also underline the risk of an increase in the speed of deforestation in the short term in tropical developing countries undergoing rapid population expansion. PMID:23789079

Vieilledent, Ghislain; Grinand, Clovis; Vaudry, Romuald

2013-01-01

232

Screening molecules for control of citrus huanglongbing using an optimized regeneration system for 'Candidatus Liberibacter asiaticus'-infected periwinkle (Catharanthus roseus) cuttings.  

PubMed

Citrus huanglongbing is one of the most destructive diseases of citrus worldwide. The disease is associated with three different species of 'Candidatus Liberibacter', of which 'Ca. L. asiaticus' is the most widely distributed. An optimized system using 'Ca. L. asiaticus'-infected periwinkle cuttings was developed to screen chemical compounds effective for controlling the bacterial population while simultaneously assessing their phytotoxicity. The optimal regeneration conditions were determined to be the use of vermiculite as a growth medium for the cuttings, and a fertilization routine using half-strength Murashige and Tucker medium supplemented with both naphthalene acetic acid (4 microg/ml) and indole-3-butyric acid (4 microg/ml). This system allowed a plant regeneration rate of 60.6% for 'Ca. L. asiaticus'-infected cuttings in contrast to the <1% regeneration rate with water alone. Two chemical agents, penicillin G sodium and 2,2-dibromo-3-nitrilopropionamide (DBNPA), were found to be effective at eliminating or suppressing the 'Ca. L. asiaticus' bacterium in this periwinkle regeneration system. When treated with penicillin G sodium at 50 microg/ml, all plants regenerated from 'Ca. L. asiaticus'-infected cuttings were 'Ca. L. asiaticus' negative as determined by both nested polymerase chain reaction (PCR) and quantitative real-time PCR. In addition, DBNPA was also able to significantly reduce the percentage of 'Ca. L. asiaticus'-positive plants and the titer of the 'Ca. L. asiaticus' bacterium at 200 microl/liter. PMID:20128697

Zhang, Muqing; Duan, Yongping; Zhou, Lijuan; Turechek, William W; Stover, Ed; Powell, Charles A

2010-03-01

233

Trans-oceanic and endemic origins of the small minnow mayflies (Ephemeroptera, Baetidae) of Madagascar  

PubMed Central

We investigated the relative importance of dispersal and vicariance in forming the Madagascar insect fauna, sequencing approximately 2300?bp from three rRNA gene regions to investigate the phylogeny of Afrotropical small minnow mayflies (Ephemeroptera: Baetidae). Six lineages contained trans-oceanic sister taxa, and variation in genetic divergence between sister taxa revealed relationships that range from very recent dispersal to ancient vicariance. Dispersal was most recent and frequent in species that spend the larval stage in standing water, adding to evidence that these evolutionarily unstable habitats may select for ecological traits that increase dispersal in insects. Ancestral state likelihood analysis suggested at least one Afrotropical lineage had its origin in Madagascar, demonstrating that unidirectional dispersal from a continental source may be too simplistic. We conclude that the Malagasy mayfly fauna should be considered in a biogeographical context that extends beyond Madagascar itself, encompassing trans-oceanic dispersal within multiple lineages. PMID:16096096

Monaghan, Michael T; Gattolliat, Jean-Luc; Sartori, Michel; Elouard, Jean-Marc; James, Helen; Derleth, Pascale; Glaizot, Olivier; de Moor, Ferdy; Vogler, Alfried P

2005-01-01

234

Comprehensive Red List assessment reveals exceptionally high extinction risk to Madagascar palms.  

PubMed

The establishment of baseline IUCN Red List assessments for plants is a crucial step in conservation planning. Nowhere is this more important than in biodiversity hotspots that are subject to significant anthropogenic pressures, such as Madagascar. Here, all Madagascar palm species are assessed using the IUCN Red List categories and criteria, version 3.1. Our results indicate that 83% of the 192 endemic species are threatened, nearly four times the proportion estimated for plants globally and exceeding estimates for all other comprehensively evaluated plant groups in Madagascar. Compared with a previous assessment in 1995, the number of Endangered and Critically Endangered species has substantially increased, due to the discovery of 28 new species since 1995, most of which are highly threatened. The conservation status of most species included in both the 1995 and the current assessments has not changed. Where change occurred, more species have moved to lower threat categories than to higher categories, because of improved knowledge of species and their distributions, rather than a decrease in extinction risk. However, some cases of genuine deterioration in conservation status were also identified. Palms in Madagascar are primarily threatened by habitat loss due to agriculture and biological resource use through direct exploitation or collateral damage. The recent extension of Madagascar's protected area network is highly beneficial for palms, substantially increasing the number of threatened species populations included within reserves. Notably, three of the eight most important protected areas for palms are newly designated. However, 28 threatened and data deficient species are not protected by the expanded network, including some Critically Endangered species. Moreover, many species occurring in protected areas are still threatened, indicating that threatening processes persist even in reserves. Definitive implementation of the new protected areas combined with local community engagement are essential for the survival of Madagascar's palms. PMID:25075612

Rakotoarinivo, Mijoro; Dransfield, John; Bachman, Steven P; Moat, Justin; Baker, William J

2014-01-01

235

Long-term survival despite low genetic diversity in the critically endangered Madagascar fish-eagle  

USGS Publications Warehouse

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100-120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place high priority on maintenance of habitat requirements and reducing direct and indirect human persecution. Given the current rate of deforestation in Madagascar, we further recommend that the population be expanded to occupy a larger geographical distribution. This will help the population persist when exposed to stochastic factors (e.g. climate and disease) that may threaten a species consisting of only 200 adult individuals while inhabiting a rapidly changing landscape. ?? 2008 The Authors.

Johnson, J.A.; Tingay, R.E.; Culver, M.; Hailer, F.; Clarke, M.L.; Mindell, D.P.

2009-01-01

236

Genetic diversity and population structure of Plasmodium vivax isolates from Sudan, Madagascar, French Guiana and Armenia.  

PubMed

Polymorphic genetic markers and especially microsatellite analysis can be used to investigate multiple aspects of the biology of Plasmodium species. In the current study, we characterized 7 polymorphic microsatellites in a total of 281 Plasmodium vivax isolates to determine the genetic diversity and population structure of P. vivax populations from Sudan, Madagascar, French Guiana, and Armenia. All four parasite populations were highly polymorphic with 3-32 alleles per locus. Mean genetic diversity values was 0.83, 0.79, 0.78 and 0.67 for Madagascar, French Guiana, Sudan, and Armenia, respectively. Significant genetic differentiation between all four populations was observed. PMID:25102032

Menegon, Michela; Durand, Patrick; Menard, Didier; Legrand, Eric; Picot, Stéphane; Nour, Bakri; Davidyants, Vladimir; Santi, Flavia; Severini, Carlo

2014-10-01

237

Surveillance and control of rabies in La Reunion, Mayotte, and Madagascar  

PubMed Central

Mayotte and La Reunion islands are currently free of animal rabies and surveillance is performed by the French Human and Veterinary Public Health Services. However, dog rabies is still enzootic in Madagascar with 4 to 10 confirmed human cases each year. The number of antirabies medical centres in Madagascar is still scarce to provide easy access to the local population for post-exposure rabies prophylaxis. Furthermore, stray dog populations are considerable and attempts to control rabies by mass campaigns of dog vaccination have not received sufficient attention from the national health authorities. To address these challenges, an expanded program to control rabies needs to be initiated by the Malagasy authorities. PMID:24016204

2013-01-01

238

Surveillance and control of rabies in La Reunion, Mayotte, and Madagascar.  

PubMed

Mayotte and La Reunion islands are currently free of animal rabies and surveillance is performed by the French Human and Veterinary Public Health Services. However, dog rabies is still enzootic in Madagascar with 4 to 10 confirmed human cases each year. The number of antirabies medical centres in Madagascar is still scarce to provide easy access to the local population for post-exposure rabies prophylaxis. Furthermore, stray dog populations are considerable and attempts to control rabies by mass campaigns of dog vaccination have not received sufficient attention from the national health authorities. To address these challenges, an expanded program to control rabies needs to be initiated by the Malagasy authorities. PMID:24016204

Andriamandimby, Soa Fy; Héraud, Jean-Michel; Ramiandrasoa, Ravo; Ratsitorahina, Maherisoa; Rasambainarivo, Jhon H; Dacheux, Laurent; Lepelletier, Anthony; Goodman, Steven M; Reynes, Jean-Marc; Bourhy, Hervé

2013-01-01

239

Chow Down! Using Madagascar Hissing Cockroaches to Explore Basic Nutrition Concepts  

NSDL National Science Digital Library

The Madagascar hissing cockroach gromphadorhina portentosa) is one of the most exciting and enjoyable animals to incorporate into your science curriculum. Madagascar hissing cockroaches (MHCs) do not bite, are easy to handle, produce little odor compared to many terrarium animals, have a fascinating social structure, are easy to breed, teach students how to properly care for animals, and are very cool looking! This article describes an inquiry-based MHC activity and further questions for your students to explore. The activity and questions address basic concepts of nutrition.

Ron Wagler

2010-03-01

240

A double-flowered variety of lesser periwinkle (Vinca minor fl. pl.) that has persisted in the wild for more than 160 years  

PubMed Central

Background and Aims Homeotic transitions are usually dismissed by population geneticists as credible modes of evolution due to their assumed negative impact on fitness. However, several lines of evidence suggest that such changes in organ identity have played an important role during the origin and subsequent evolution of the angiosperm flower. Better understanding of the performance of wild populations of floral homeotic varieties should help to clarify the evolutionary potential of homeotic mutants. Wild populations of plants with changes in floral symmetry, or with reproductive organs replacing perianth organs or sepals replacing petals have already been documented. However, although double-flowered varieties are quite popular as ornamental and garden plants, they are rarely found in the wild and, if they are, usually occur only as rare mutant individuals, probably because of their low fitness relative to the wild-type. We therefore investigated a double-flowered variety of lesser periwinkle, Vinca minor flore pleno (fl. pl.), that is reported to have existed in the wild for at least 160 years. To assess the merits of this plant as a new model system for investigations on the evolutionary potential of double-flowered varieties we explored the morphological details and distribution of the mutant phenotype. Methods The floral morphology of the double-flowered variety and of a nearby population of wild-type plants was investigated by means of visual inspection and light microscopy of flowers, the latter involving dissected or sectioned floral organs. Key Results The double-flowered variety was found in several patches covering dozens of square metres in a forest within the city limits of Jena (Germany). It appears to produce fewer flowers than the wild-type, and its flowers are purple rather than blue. Most sepals in the first floral whorl resemble those in the wild-type, although occasionally one sepal is broadened and twisted. The structure of second-whorl petals is very similar to that of the wild-type, but their number per flower is more variable. The double-flowered character is due to partial or complete transformation of stamens in the third whorl into petaloid organs. Occasionally, ‘flowers within flowers’ also develop on elongated pedicels in the double-flowered variety. Conclusions The flowers of V. minor fl. pl. show meristic as well as homeotic changes, and occasionally other developmental abnormalities such as mis-shaped sepals or loss of floral determinacy. V. minor fl. pl. thus adds to a growing list of natural floral homeotic varieties that have established persistent populations in the wild. Our case study documents that even mutant varieties that have reproductive organs partially transformed into perianth organs can persist in the wild for centuries. This finding makes it at least conceivable that even double-flowered varieties have the potential to establish new evolutionary lineages, and hence may contribute to macroevolutionary transitions and cladogenesis. PMID:21527418

Wang, Yong-Qiang; Melzer, Rainer; Theißen, Günter

2011-01-01

241

An unexpected recurrent transmission of Rift Valley fever virus in cattle in a temperate and mountainous area of Madagascar.  

PubMed

Rift Valley fever is an acute, zoonotic viral disease of domestic ruminants, caused by a phlebovirus (Bunyaviridae family). A large outbreak occurred in Madagascar in 2008-2009. The goal of the present study was to evaluate the point prevalence of antibodies against Rift Valley Fever Virus (RVFV) in cattle in the Anjozorobe district, located in the wet and temperate highland region of Madagascar and yet heavily affected by the disease, and analyse environmental and trade factors potentially linked to RVFV transmission. A serological study was performed in 2009 in 894 bovines. For each bovine, the following variables were recorded: age, location of the night pen, minimum distance from the pen to the nearest water point and the forest, nearest water point type, and herd replacement practices. The serological data were analyzed using a generalized linear mixed model. The overall anti-RVFV IgG seroprevalence rate was 28% [CI95% 25-31]. Age was statistically linked to prevalence (p = 10(-4)), being consistent with a recurrent RVFV circulation. Distance from the night pen to the nearest water point was a protective factor (p = 5.10(-3)), which would be compatible with a substantial part of the virus transmission being carried out by nocturnal mosquito vectors. However, water point type did not influence the risk of infection: several mosquito species are probably involved. Cattle belonging to owners who purchase animals to renew the herd were significantly more likely to have seroconverted than others (p = 0.04): cattle trade may contribute to the introduction of the virus in this area. The minimum distance of the night pen to the forest was not linked to the prevalence. This is the first evidence of a recurrent transmission of RVFV in such an ecosystem that associates a wet, temperate climate, high altitude, paddy fields, and vicinity to a dense rain forest. Persistence mechanisms need to be further investigated. PMID:22206026

Chevalier, Veronique; Rakotondrafara, Toky; Jourdan, Marion; Heraud, Jean Michel; Andriamanivo, Harena Rasamoelina; Durand, Benoit; Ravaomanana, Julie; Rollin, Pierre E; Rakotondravao, René

2011-12-01

242

Human and environmental controls over aboveground carbon storage in Madagascar  

PubMed Central

Background Accurate, high-resolution mapping of aboveground carbon density (ACD, Mg C ha-1) could provide insight into human and environmental controls over ecosystem state and functioning, and could support conservation and climate policy development. However, mapping ACD has proven challenging, particularly in spatially complex regions harboring a mosaic of land use activities, or in remote montane areas that are difficult to access and poorly understood ecologically. Using a combination of field measurements, airborne Light Detection and Ranging (LiDAR) and satellite data, we present the first large-scale, high-resolution estimates of aboveground carbon stocks in Madagascar. Results We found that elevation and the fraction of photosynthetic vegetation (PV) cover, analyzed throughout forests of widely varying structure and condition, account for 27-67% of the spatial variation in ACD. This finding facilitated spatial extrapolation of LiDAR-based carbon estimates to a total of 2,372,680 ha using satellite data. Remote, humid sub-montane forests harbored the highest carbon densities, while ACD was suppressed in dry spiny forests and in montane humid ecosystems, as well as in most lowland areas with heightened human activity. Independent of human activity, aboveground carbon stocks were subject to strong physiographic controls expressed through variation in tropical forest canopy structure measured using airborne LiDAR. Conclusions High-resolution mapping of carbon stocks is possible in remote regions, with or without human activity, and thus carbon monitoring can be brought to highly endangered Malagasy forests as a climate-change mitigation and biological conservation strategy. PMID:22289685

2012-01-01

243

An endangered new species of edible yam (Dioscorea, Dioscoreaceae) from Western Madagascar and its conservation  

E-print Network

An endangered new species of edible yam (Dioscorea, Dioscoreaceae) from Western Madagascar and its Louis Jeannoda4 , & Claude Marcel Hladik3 Summary. A new species of Dioscorea from Morondava prefecture and is endangered under IUCN Red List category criteria (IUCN 2001). The unusual morphological features of its

Paris-Sud XI, Université de

244

DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar  

Microsoft Academic Search

The role of DNA barcoding as a tool to accelerate the inventory and analysis of diversity for hyperdiverse arthropods is tested using ants in Madagascar. We demonstrate how DNA barcoding helps address the failure of current inventory methods to rapidly respond to pressing biodiversity needs, specifically in the assessment of richness and turnover across landscapes with hyperdiverse taxa. In a

M. Alex Smith; Brian L. Fisher; Paul D. N. Hebert

2005-01-01

245

Designing the Masoala National Park in Madagascar Based on Biological and Socioeconomic Data  

Microsoft Academic Search

Conservation biologists have developed powerful tools for reserve selection and design over the past two decades, yet seldom are protected areas actually designed on scientific grounds. Using fundamental biological and socioeconomic principles of conservation science, we designed a new protected area and its multiple-use zone on the Masoala Peninsula in the humid forest zone of Madagascar. The explicit design cri-

Claire Kremen; Vincent Razafimahatratra; R. Philip Guillery; Jocelyn Rakotomalala; Andrew Weiss; Jean-Solo Ratsisompatrarivo

1999-01-01

246

A framework for understanding community resident perceptions of Masoala National Park, Madagascar  

Microsoft Academic Search

SUMMARY Protected areas (PAs) represent a central strategy in biodiversity conservation worldwide. Yet many PAs are weakened by people-PA conflicts resulting from the separation of natural resource protection from human considerations. Research at Masoala National Park in Madagascar focused on the following questions: (1) What are the factors that influence residents' perceptions of the Park and restrictions on use of

ALISON ORMSBY; BETH A. KAPLIN

2005-01-01

247

Home Sweet Home: How to Build a Madagascar Hissing Cockroach Habitat out of Recycled Materials  

ERIC Educational Resources Information Center

Madagascar hissing cockroaches (MHC) are amazing insects that can be an integral part of an effective science learning and teaching environment. MHCs have a fascinating social structure. They make excellent pets, teach students how to properly care for animals, and their large size adds to their "wow" factor. These characteristics make them unique…

Wagler, Ron

2010-01-01

248

Genetics of the Pig Tapeworm in Madagascar Reveal a History of Human Dispersal and Colonization  

PubMed Central

An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation. PMID:25329310

Yanagida, Tetsuya; Carod, Jean-François; Sako, Yasuhito; Nakao, Minoru; Hoberg, Eric P.; Ito, Akira

2014-01-01

249

Ecotourism Benefits and the Role of Local Guides at Masoala National Park, Madagascar  

Microsoft Academic Search

An investigation of ecotourism at Masoala National Park, a forested coastal area in northeastern Madagascar and the country’s largest national park, focused on ecotourism benefits and the role of local guides in promoting conservation awareness. Interviews, participant observation, and archival research were used to investigate the park’s guide association, resident attitudes toward Masoala National Park, and ecotourism as a method

Alison Ormsby; Kathryn Mannle

2006-01-01

250

The distribution and conservation of bats in the dry regions of Madagascar  

Microsoft Academic Search

We carried out extensive field surveys in the dry forest portions of Madagascar to document the species of bats occurring in these regions. These data combined with information in the literature and museum specimen records indicate that 28 species of Chiroptera occur in this region of the island, of which we documented 27 during our inventories. The community composition at

Steven M. Goodman; Daudet Andriafidison; Radosoa Andrianaivoarivelo; Scott G. Cardiff; Edina Ifticene; Richard K. B. Jenkins; Amyot Kofoky; Tsibara Mbohoahy; Daniel Rakotondravony; Julie Razafimanahaka; Fanja Ratrimomanarivo; Paul A. Racey

2005-01-01

251

Late Cretaceous IndiaMadagascar fit and timing of break-up related magmatism  

E-print Network

Late Cretaceous India±Madagascar fit and timing of break-up related magmatism T. H. Torsvik1 *, R et al., 1995; Torsvik et al., 1998). During this Late Cretaceous break-up event, the western margin reconstruction, south-west India runs roughly subparallel with the first known break-up related magnetic anomaly

Torsvik, Trond Helge

252

Understanding Mortality and the Life of the Ancestors in Rural Madagascar  

ERIC Educational Resources Information Center

Across two studies, a wide age range of participants was interviewed about the nature of death. All participants were living in rural Madagascar in a community where ancestral beliefs and practices are widespread. In Study 1, children (8-17 years) and adults (19-71 years) were asked whether bodily and mental processes continue after death. The…

Astuti, Rita; Harris, Paul L.

2008-01-01

253

Tree Structure and Diversity in Human-Impacted Littoral Forests, Madagascar  

Microsoft Academic Search

This research surveyed human-impacted littoral forests in southeastern Madagascar to determine (i) how forest structural features, indicative of human impact, are related to total, utilitarian, and endemic tree diversity; (ii) the distribution, abundance, and demographics of tree species groups (i.e., total, useful, endemic) across the landscape; and (iii) the amount of basal area available per human use category. We also

J. Carter Ingram; Robert J. Whittaker; Terence P. Dawson

2005-01-01

254

Preliminary data on genetic differentiation within the Madagascar spider tortoise Preliminary data on genetic differentiation  

E-print Network

). All endemic spe- cies are considered to be endangered or vul- nerable according to IUCN classification arachnoides, is one of the four extant endemic terrestrial chelonian species of Madagascar. Although this species is considered to be vulnerable, little is known about the status and genetic differentiation

Vieites, David R.

255

Drug-Resistant Malaria Parasites Introduced into Madagascar from Comoros Islands  

PubMed Central

To determine risk for drug-resistant malaria parasites entering Madagascar from Comoros Islands, we screened travelers. For the 141 Plasmodium falciparum isolates detected by real-time PCR, frequency of mutant alleles of genes associated with resistance to chloroquine and pyrimethamine was high. International-level antimalarial policy and a regional antimalarial forum are needed. PMID:18217565

Randrianarivo-Solofoniaina, Armand Eugène; Ahmed, Bedja Said; Jahevitra, Martial; Andriantsoanirina, Landy Valérie; Rasolofomanana, Justin Ranjalahy; Rabarijaona, Léon Paul

2007-01-01

256

Origins of the Recent Emergence of Plasmodium falciparum Pyrimethamine Resistance Alleles in Madagascar? †  

PubMed Central

The combination of sulfadoxine-pyrimethamine is recommended for use as intermittent preventive treatment of malaria during pregnancy and is deployed in Africa. The emergence and the spread of resistant parasites are major threats to such an intervention. We have characterized the Plasmodium falciparum dhfr (pfdhfr) haplotypes and flanking microsatellites in 322 P. falciparum isolates collected from the Comoros Islands and Madagascar. One hundred fifty-six (48.4%) carried the wild-type pfdhfr allele, 19 (5.9%) carried the S108N single-mutation allele, 30 (9.3%) carried the I164L single-mutation allele, 114 (35.4%) carried the N51I/C59R/S108N triple-mutation allele, and 3 (1.0%) carried the N51I/C59R/S108N/I164L quadruple-mutation allele. Microsatellite analysis showed the introduction from the Comoros Islands of the ancestral pfdhfr triple mutant allele of Asian origin and its spread in Madagascar. Evidence for the emergence on multiple occasions of the I164L single-mutation pfdhfr allele in Madagascar was also obtained. Thus, the conditions required to generate mutants with quadruple mutations are met in Madagascar, representing a serious threat to current drug policy. PMID:20308388

Andriantsoanirina, Valérie; Bouchier, Christiane; Tichit, Magali; Jahevitra, Martial; Rabearimanana, Stéphane; Randrianjafy, Rogelin; Ratsimbasoa, Arsène; Mercereau-Puijalon, Odile; Durand, Rémy; Ménard, Didier

2010-01-01

257

The ecology and conservation status of Madagascar's endemic freshwater crayfish (Parastacidae; Astacoides)  

Microsoft Academic Search

SUMMARY 1. Freshwater crayfish of the genus Astacoides are endemic to the highlands of eastern Madagascar. Very little is known about their ecology and how this affects their vulnerability to threats. Working in the Fianarantsoa forest corridor, we used a combination of ecological research (>29 000 crayfish caught and released) and interviews (>130 interviews in 38 villages) to investigate the

JULIA P. G. J ONES; F ORTUNAT B. A NDRIAHAJAINA; N EAL; J. H OCKLEY

258

THE subfossil occurrence and paleoecological significance of small mammals at ankilitelo cave, southwestern Madagascar  

USGS Publications Warehouse

Small mammals are rarely reported from subfossil sites in Madagascar despite their importance for paleoenvironmental reconstruction, especially as it relates to recent ecological changes on the island. We describe the uniquely rich subfossil small mammal fauna from Ankilitelo Cave, southwestern Madagascar. The Ankilitelo fauna is dated to the late Holocene (???500 years ago), documenting the youngest appearances of the extinct giant lemur taxa Palaeopropithecus, Megaladapis, and Archaeolemur, in association with abundant remains of small vertebrates, including bats, tenrecs, carnivorans, rodents, and primates. The Ankilitelo fauna is composed of 34 mammalian species, making it one of the most diverse Holocene assemblages in Madagascar. The fauna comprises the 1 st report of the short-tailed shrew tenrec (Microgale brevicaudata) and the ring-tailed mongoose (Galidia elegans) in southwestern Madagascar. Further, Ankilitelo documents the presence of southwestern species that are rare or that have greatly restricted ranges today, such as Nasolo's shrew tenrec (M. nasoloi), Grandidier's mongoose (Galidictis grandidieri), the narrow-striped mongoose (Mungotictis decemlineata), and the giant jumping rat (Hypogeomys antimena). A simple cause for the unusual small mammal occurrences at Ankilitelo is not obvious. Synergistic interactions between climate change, recent fragmentation and human-initiated degradation of forested habitats, and community-level processes, such as predation, most likely explain the disjunct distributions of the small mammals documented at Ankilitelo. ?? 2009 American Society of Mammalogists.

Muldoon, K.M.; De Blieux, D. D.; Simons, E.L.; Chatrath, P.S.

2009-01-01

259

Examining the Environmental Awareness of Children and Adolescents in the Ranomafana Region, Madagascar  

ERIC Educational Resources Information Center

This paper examines children's and adolescents' environmental awareness in rural Madagascar. Two types of school survey among 8- to 21-year-old students and pupils in 18 schools were used for data collection. The objective of this comparative study was to examine the environmental awareness and knowledge of children and adolescents living under…

Korhonen, Kaisa; Lappalainen, Anu

2004-01-01

260

New material of Dadadon isaloi (Cynodontia, Traversodontidae) from the Triassic of Madagascar  

Microsoft Academic Search

New material of the traversodontid cynodont Dadadon isaloi from the Triassic of southwestern Madagascar is described. The new material consists of a complete, well-preserved skull (FMNH PR 2232) and an unassociated, partial lower jaw (UA 10608). The new material reveals several novel aspects of Dadadon's morphology. Newly recognized autapomorphies that diagnose Dadadon include a fourth upper incisor with posterior accessory

Lovasoa Ranivoharimanana; Christian F. Kammerer; John J. Flynn; André R. Wyss

2011-01-01

261

Which Advisory System to Support Innovation in Conservation Agriculture? The Case of Madagascar's Lake Alaotra  

ERIC Educational Resources Information Center

Purpose: To promote sustainable agriculture, various development projects are encouraging farmers around Madagascar's Lake Alaotra to adopt conservation agriculture techniques. This article's objective is to analyze the capacity of a project-funded advisory system to accompany such an innovation and to design and implement an advisory method aimed…

Faure, Guy; Penot, Eric; Rakotondravelo, Jean Chrysostome; Ramahatoraka, Haja Andrisoa; Dugue, Patrick; Toillier, Aurelie

2013-01-01

262

Effect of human disturbance on arthropod diversity at Kirindy Forest, Western Madagascar  

Microsoft Academic Search

The arthropod fauna of Madagascar is remarkably diverse and includes many endemic genera, yet it remains poorly documented and under increasing threat from human disturbance. Not only does the current state of Madagascan arthropod fauna deserve better characterisation, it also provides as yet unrealised potential as a powerful tool in conservation monitoring. We investigate the relationship between diversity of arthropod

Claudia Gray; Evelien Jongepier

263

Habituation of hissing by Madagascar hissing cockroaches ( Gromphadorhina portentosa): evidence of discrimination between humans?  

Microsoft Academic Search

Anecdotal reports suggest that insects can be “tamed” with frequent human contact. In the present experiment, repeated handling of Madagascar hissing cockroaches by the same person resulted in habituation of the hissing response in ten of 12 subjects. These subjects were then handled by a novel person in order to determine whether habituation might be specific to a particular human.

Hank Davis; Emily Heslop

2004-01-01

264

Semiochemical parsimony between the Madagascar hissing-cockroach mite and its host  

Microsoft Academic Search

The behavior of conspecific mites (Gromphadorholaelaps schaeferi Till) on the giant Madagascar hissing-cockroach was explored by examining responses towards one another and towards their lipid extracts. Because mites did not display significant attraction or repelling behaviors characteristic of assembly, aggregation, alarm, or sex pheromone production, their occurrence is likely attributed to the behavior-modifying attractive properties of the cockroach's unique musty

Jay A. Yoder; Syed S. Mahmood; Peter N. Lalli

2001-01-01

265

A Late Cretaceous (Maastrichtian) snake assemblage from the Maevarano Formation, Mahajanga Basin, Madagascar  

Microsoft Academic Search

A Late Cretaceous (Maastrichtian) assemblage of snakes from the Maevarano Formation of the Mahajanga Basin, northwestern Madagascar, constitutes the only fossil record of snakes from the island. The assemblage, which lived in a highly seasonal, semi-arid climate, includes only archaic forms belonging to the Madtsoiidae and Nigerophiidae, and therefore no representatives of extant Malagasy clades. A large sample of exquisitely

Thomas C. Laduke; David W. Krause; John D. Scanlon; Nathan J. Kley

2010-01-01

266

Reducing water use in irrigated rice production with the Madagascar System of Rice Intensification (SRI)  

Microsoft Academic Search

The System of Rice Intensification (SRI) developed in Madagascar increases yields substantially, 50% to 100% or more, while requiring only about half as much water as conventional rice. There is no need for different varieties or to purchase external inputs. Most water-saving methods to date show little de- cline in yield or, at most, small gains in output. The large

N. Uphoff; R. Randriamiharisoa

267

Ecology of subtropical hermit crabs in SW Madagascar: short-range migrations  

Microsoft Academic Search

Many mobile animals migrate because of the different benefits provided by different localities in time and space. For hermit crabs, such benefits include resource (shell, water, food) acquisition and gamete release. One of the more successful crustacean land-invaders, Coenobita hermit crabs, undertake complex short-range migrations in SW Madagascar. Number of active hermit crabs was inversely related to wind strength and

D. Barnes

2003-01-01

268

Improving Management in Education: Evidence from a Randomized Experiment in Madagascar1  

Microsoft Academic Search

This paper evaluates several interventions in Madagascar that sought to promote top- down and local monitoring of the school to improve education quality. Randomly selected school districts and subdistricts received operational tools to facilitate the administrators' supervision tasks. Randomly selected schools in these treated districts were reinforced with teacher tools and parent-teacher meetings centered around a school report card. The

Trang Nguyen

269

Salicylic acid mitigates salinity stress by improving antioxidant defence system and enhances vincristine and vinblastine alkaloids production in periwinkle [ Catharanthus roseus (L.) G. Don  

Microsoft Academic Search

A pot experiment was conducted to find out whether the foliar spray of salicylic acid (SA) could successfully ameliorate the\\u000a adverse effects of salinity stress on periwinkle. Thirty-day-old plants were supplied with Control; 0 mM NaCl + 10?5 M SA (T1); 50 mM NaCl + 0 SA (T2); 100 mM NaCl + 0 SA (T3); 150 mM NaCl + 0 SA (T4); 50 mM NaCl + 10?5 M SA (T5); 100 mM NaCl + 10?5 M SA (T6); 150 mM NaCl + 10?5 M SA

Mohd Idrees; M. Naeem; Tariq Aftab; M. Masroor A. Khan; Moinuddin

2011-01-01

270

In or Out-of-Madagascar?—Colonization Patterns for Large-Bodied Diving Beetles (Coleoptera: Dytiscidae)  

PubMed Central

High species diversity and endemism within Madagascar is mainly the result of species radiations following colonization from nearby continents or islands. Most of the endemic taxa are thought to be descendants of a single or small number of colonizers that arrived from Africa sometime during the Cenozoic and gave rise to highly diverse groups. This pattern is largely based on vertebrates and a small number of invertebrate groups. Knowledge of the evolutionary history of aquatic beetles on Madagascar is lacking, even though this species-rich group is often a dominant part of invertebrate freshwater communities in both standing and running water. Here we focus on large bodied diving beetles of the tribes Hydaticini and Cybistrini. Our aims with this study were to answer the following questions 1) How many colonization events does the present Malagasy fauna originate from? 2) Did any colonization event lead to a species radiation? 3) Where did the colonizers come from—Africa or Asia—and has there been any out-of-Madagascar event? 4) When did these events occur and were they concentrated to any particular time interval? Our results suggest that neither in Hydaticini nor in Cybistrini was there a single case of two or more endemic species forming a monophyletic group. The biogeographical analysis indicated different colonization histories for the two tribes. Cybistrini required at least eight separate colonization events, including the non-endemic species, all comparatively recent except the only lotic (running water) living Cybister operosus with an inferred colonization at 29 Ma. In Hydaticini the Madagascan endemics were spread out across the tree, often occupying basal positions in different species groups. The biogeographical analyses therefore postulated the very bold hypothesis of a Madagascan origin at a very deep basal node within Hydaticus and multiple out-of-Madagascar dispersal events. This hypothesis needs to be tested with equally intense taxon sampling of mainland Africa as for Madagascar. PMID:25794184

Bukontaite, Rasa; Ranarilalatiana, Tolotra; Randriamihaja, Jacquelin Herisahala; Bergsten, Johannes

2015-01-01

271

Madagascar corals reveal a multidecadal signature of rainfall and river runoff since 1708  

NASA Astrophysics Data System (ADS)

Pacific Ocean sea surface temperatures (SST) influence rainfall variability on multidecadal and interdecadal timescales in concert with the Pacific Decadal Oscillation (PDO) and Interdecadal Pacific Oscillation (IPO). Rainfall variations in locations such as Australia and North America are therefore linked to phase changes in the PDO. Furthermore, studies have suggested teleconnections exist between the western Indian Ocean and Pacific Decadal Variability (PDV), similar to those observed on interannual timescales related to the El Niño Southern Oscillation (ENSO). However, as instrumental records of rainfall are too short and sparse to confidently assess multidecadal climatic teleconnections, here we present four coral climate archives from Madagascar spanning up to the past 300 yr (1708-2008) to assess such decadal variability. Using spectral luminescence scanning to reconstruct past changes in river runoff, we identify significant multidecadal and interdecadal frequencies in the coral records, which before 1900 are coherent with Asian-based PDO reconstructions. This multidecadal relationship with the Asian-based PDO reconstructions points to an unidentified teleconnection mechanism that affects Madagascar rainfall/runoff, most likely triggered by multidecadal changes in North Pacific SST, influencing the Asian Monsoon circulation. In the 20th century we decouple human deforestation effects from rainfall-induced soil erosion by pairing luminescence with coral geochemistry. Positive PDO phases are associated with increased Indian Ocean temperatures and runoff/rainfall in eastern Madagascar, while precipitation in southern Africa and eastern Australia declines. Consequently, the negative PDO phase that started in 1998 may contribute to reduced rainfall over eastern Madagascar and increased precipitation in southern Africa and eastern Australia. We conclude that multidecadal rainfall variability in Madagascar and the western Indian Ocean needs to be taken into account when considering water resource management under a future warming climate.

Grove, C. A.; Zinke, J.; Peeters, F.; Park, W.; Scheufen, T.; Kasper, S.; Randriamanantsoa, B.; McCulloch, M. T.; Brummer, G.-J. A.

2013-03-01

272

In or Out-of-Madagascar?-Colonization Patterns for Large-Bodied Diving Beetles (Coleoptera: Dytiscidae).  

PubMed

High species diversity and endemism within Madagascar is mainly the result of species radiations following colonization from nearby continents or islands. Most of the endemic taxa are thought to be descendants of a single or small number of colonizers that arrived from Africa sometime during the Cenozoic and gave rise to highly diverse groups. This pattern is largely based on vertebrates and a small number of invertebrate groups. Knowledge of the evolutionary history of aquatic beetles on Madagascar is lacking, even though this species-rich group is often a dominant part of invertebrate freshwater communities in both standing and running water. Here we focus on large bodied diving beetles of the tribes Hydaticini and Cybistrini. Our aims with this study were to answer the following questions 1) How many colonization events does the present Malagasy fauna originate from? 2) Did any colonization event lead to a species radiation? 3) Where did the colonizers come from-Africa or Asia-and has there been any out-of-Madagascar event? 4) When did these events occur and were they concentrated to any particular time interval? Our results suggest that neither in Hydaticini nor in Cybistrini was there a single case of two or more endemic species forming a monophyletic group. The biogeographical analysis indicated different colonization histories for the two tribes. Cybistrini required at least eight separate colonization events, including the non-endemic species, all comparatively recent except the only lotic (running water) living Cybister operosus with an inferred colonization at 29 Ma. In Hydaticini the Madagascan endemics were spread out across the tree, often occupying basal positions in different species groups. The biogeographical analyses therefore postulated the very bold hypothesis of a Madagascan origin at a very deep basal node within Hydaticus and multiple out-of-Madagascar dispersal events. This hypothesis needs to be tested with equally intense taxon sampling of mainland Africa as for Madagascar. PMID:25794184

Bukontaite, Rasa; Ranarilalatiana, Tolotra; Randriamihaja, Jacquelin Herisahala; Bergsten, Johannes

2015-01-01

273

Rainforest pharmacopeia in Madagascar provides high value for current local and prospective global uses.  

PubMed

Botanical diversity provides value to humans through carbon sequestration, air and water purification, and the provisioning of wild foods and ethnomedicines. Here we calculate the value of botanical ethnomedicines in a rainforest region of Madagascar, the Makira Protected Area, using a substitution method that combines replacement costs and choice modeling. The Makira watershed may comprise approximately 0.8% of global botanical diversity and possesses enormous value both in its ability to provision botanical ethnomedicines to local people and as a source of potentially novel pharmaceutical drugs for society as a whole. Approximately 241 locally-recognized species are used as ethnomedicines, including 113 agricultural or weed species. We equated each ethnomedicinal treatment to the monetary value of a comparable pharmaceutical treatment adjusted by personal preferences in perceived efficacy (rather than from known or assumed medicinal equivalency). The benefit value of these botanical ethnomedicines per individual is $5.40-7.90 per year when using the value of highly subsidized Malagasy pharmaceuticals and $100.60-287.40 when using the value of American pharmaceuticals. Using local pharmaceuticals as substitutes, the value per household is $30.24-44.30 per year, equivalent to 43-63% of median annual household income, demonstrating their local importance. Using the value of American pharmaceuticals, the amount is equivalent to 22-63% of the median annual health care expenditures for American adults under 45 in 2006. The potential for developing novel biomedicines from the Makira watershed's unique flora ranges in untapped benefit value from $0.3-5.7 billion for American pharmaceutical companies, non-inclusive of the importance of providing novel medicines and improved healthcare to society. This study provides evidence of the tremendous current local and prospective global value of botanical ethnomedicines and furthers arguments for the conservation of tropical forests for sustainable use. PMID:22848447

Golden, Christopher D; Rasolofoniaina, B J Rodolph; Anjaranirina, E J Gasta; Nicolas, Lilien; Ravaoliny, Laurent; Kremen, Claire

2012-01-01

274

Geological evolution of the Antongil Craton, NE Madagascar  

USGS Publications Warehouse

The Antongil Craton, along with the Masora and Antananarivo cratons, make up the fundamental Archaean building blocks of the island of Madagascar. They were juxtaposed during the late-Neoproterozoic to early Palaeozoic assembly of Gondwana. In this paper we give a synthesis of the geology of the Antongil Craton and present previously published and new geochemical and U-Pb zircon analyses to provide an event history for its evolution.The oldest rocks in the Antongil Craton form a nucleus of tonalitic gneiss, characteristic of Palaeo-Mesoarchaean cratons globally, including phases dated between 3320 ?? 14. Ma to 3231 ?? 6. Ma and 3187 ?? 2. Ma to 3154 ?? 5. Ma. A series of mafic dykes was intruded into the Mesoarchaean tonalites and a sedimentary succession was deposited on the craton prior to pervasive deformation and migmatisation of the region. The age of deposition of the metasediments has been constrained from a volcanic horizon to around 3178 ?? 2. Ma and subject to migmatisation at around 2597 ?? 49. Ma. A subsequent magmatic episode generated voluminous, weakly foliated granitic rocks, that also included additions from both reworked older crustal material and younger source components. An earlier granodiorite-dominated assemblage, dated between 2570 ?? 18. Ma and 2542 ?? 5. Ma, is largely exposed in xenoliths and more continuously in the northern part of the craton, while a later monzogranite-dominated phase, dated between 2531 ?? 13. Ma and 2513 ?? 0.4. Ma is more widely developed. Together these record the stabilisation of the craton, attested to by the intrusion of a younger dyke swarm, the age of which is constrained by a sample of metagabbro dated at 2147 ?? 6. Ma, providing the first evidence for Palaeoproterozoic rocks from the Antongil Craton.The youngest events recorded in the isotopic record of the Antongil Craton are reflected in metamorphism, neocrystallisation and Pb-loss at 792 ?? 130. Ma to 763 ?? 13. Ma and 553 ?? 68. Ma. These events are interpreted as being the only manifestation of the Pan-African orogeny seen in the craton, which led to the assembly of the tectonic blocks that comprise the island. ?? 2010 NERC.

Schofield, D.I.; Thomas, Ronald J.; Goodenough, K.M.; De Waele, B.; Pitfield, P.E.J.; Key, R.M.; Bauer, W.; Walsh, G.J.; Lidke, D.J.; Ralison, A.V.; Rabarimanana, M.; Rafahatelo, J.-M.; Randriamananjara, T.

2010-01-01

275

Filling the Gondwana gaps: new species and new reports of Beatogordius Heinze, 1934 (Nematomorpha) from Australia and Madagascar  

Microsoft Academic Search

We describe two new species of Beatogordius Heinze, 1934 (Nematomorpha), B. australiensis and B. lineatus, from Queensland, Australia. One further species, B. abbreviatus (Villot, 1874), which was known from Reunion, is reported from Madagascar. These new reports extend the range of Beatogordius from Africa and South America to include Madagascar and Australia. Beatogordius was likely distributed over the Gondwana continent prior to the

Andreas Schmidt-Rhaesa; Malcom S. Bryant

2004-01-01

276

Description of nesting and foraging habitat of the Madagascar Fish-eagle Haliaeetus vociferoides: a conservation initiative  

Microsoft Academic Search

Watson R.T., Berkelman J., Rabarisoa R., Thorstrom R., & Watson C.R.B. 2000. Description of nesting and foraging habitat of the Madagascar Fish-Eagle Haliaeetus vociferoides: a conservation initiative. Ostrich 71 (1 & 2): 336–340.Recent surveys indicate the Madagascar Fish-Eagle Haliaeetus vociferoides population is about 100 breeding pairs; the species is considered among the most endangered birds of prey worldwide. This paper

Richard T. Watson; James Berkelman; Rivo Rabarisoa; Russell Thorstrom; Christine R. B. Watson

2000-01-01

277

A link between low-frequency mesoscale eddy variability around Madagascar and the large-scale Indian Ocean variability  

Microsoft Academic Search

A connection is shown to exist between the mesoscale eddy activity around Madagascar and the large-scale interannual variability in the Indian Ocean. We use the combined TOPEX\\/Poseidon-ERS sea surface height (SSH) data for the period 1993–2003. The SSH-fields in the Mozambique Channel and east of Madagascar exhibit a significant interannual oscillation. This is related to the arrival of large-scale anomalies

V. Palastanga; P. J. van Leeuwen; W. P. M. de Ruijter

2006-01-01

278

Rainforest Pharmacopeia in Madagascar Provides High Value for Current Local and Prospective Global Uses  

PubMed Central

Botanical diversity provides value to humans through carbon sequestration, air and water purification, and the provisioning of wild foods and ethnomedicines. Here we calculate the value of botanical ethnomedicines in a rainforest region of Madagascar, the Makira Protected Area, using a substitution method that combines replacement costs and choice modeling. The Makira watershed may comprise approximately 0.8% of global botanical diversity and possesses enormous value both in its ability to provision botanical ethnomedicines to local people and as a source of potentially novel pharmaceutical drugs for society as a whole. Approximately 241 locally-recognized species are used as ethnomedicines, including 113 agricultural or weed species. We equated each ethnomedicinal treatment to the monetary value of a comparable pharmaceutical treatment adjusted by personal preferences in perceived efficacy (rather than from known or assumed medicinal equivalency). The benefit value of these botanical ethnomedicines per individual is $5.40–7.90 per year when using the value of highly subsidized Malagasy pharmaceuticals and $100.60–287.40 when using the value of American pharmaceuticals. Using local pharmaceuticals as substitutes, the value per household is $30.24–44.30 per year, equivalent to 43–63% of median annual household income, demonstrating their local importance. Using the value of American pharmaceuticals, the amount is equivalent to 22–63% of the median annual health care expenditures for American adults under 45 in 2006. The potential for developing novel biomedicines from the Makira watershed’s unique flora ranges in untapped benefit value from $0.3–5.7 billion for American pharmaceutical companies, non-inclusive of the importance of providing novel medicines and improved healthcare to society. This study provides evidence of the tremendous current local and prospective global value of botanical ethnomedicines and furthers arguments for the conservation of tropical forests for sustainable use. Botanique de la diversité apporte de la valeur à l’homme par la séquestration du carbone, de l’air et de purification de l’eau, et le provisionnement des aliments sauvages et ethnomedicines. Ici, nous calculons la valeur de ethnomedicines botaniques dans une région de forêt de Madagascar, la zone protégée de Makira, en utilisant une méthode de substitution qui combine les coûts de remplacement et la modélisation des choix. Le bassin versant de Makira peut comprendre environ 0,8% de la diversité botanique mondiale et possède une valeur énorme à la fois dans sa capacité à fournir ethnomedicines botaniques à la population locale et en tant que source de nouveaux médicaments potentiellement pharmaceutiques pour la société dans son ensemble. Environ 241 espèces localement reconnus sont utilisés comme ethnomedicines, y compris 113 espèces d’agricoles ou de mauvaises herbes. Nous assimilé chaque traitement ethnomédicales à la valeur monétaire d’un traitement comparable pharmaceutique ajusté en fonction des préférences personnelles en matière d’efficacité perçue (plutôt que de l’équivalence médicament connu ou supposé). La valeur de l’avantage de ces ethnomedicines botaniques par individu est de $5,40 à 7.90 par année lors de l’utilisation de la valeur des produits pharmaceutiques malgaches fortement subventionnés et de $100,60 à 287,40 lors de l’utilisation de la valeur des produits pharmaceutiques américains. Utilisation de produits pharmaceutiques locales comme des substituts, la valeur par ménage est de $30.24 à 44.30 par an, équivalent à 43–63% du revenu médian des ménages annuelle, ce qui démontre leur importance locale. Utilisation de la valeur des produits pharmaceutiques

Golden, Christopher D.; Rasolofoniaina, B. J. Rodolph; Anjaranirina, E. J. Gasta; Nicolas, Lilien; Ravaoliny, Laurent; Kremen, Claire

2012-01-01

279

Les transferts de gestion des ressources naturelles : quelles consquences sur les systmes socio-cologiques de fort sche Madagascar et au Niger ?  

E-print Network

-écologiques de forêt sèche à Madagascar et au Niger ? Auteurs : Rives Fanny, Aubert Sigrid et Montagne Pierre Résumé Dans les zones de forêts sèches à Madagascar et au Niger, les systèmes socio-écologiques sont pour comprendre comment les politiques forestières ont évolué à Madagascar et au Niger pour atteindre

Boyer, Edmond

280

Community management of natural resources: a case study from Ankarafantsika National Park, Madagascar.  

PubMed

We analyzed the management, resource use and conservation of the Ankarafantsika National Park (Madagascar) to develop a management plan, which provides a sustainable development strategy of the area while empowering the local residents. Using qualitative methodology we performed interviews with villagers and local organizations to assess the park's successes and failures from local stakeholders' perspectives. People living in a village with a permanent Madagascar National Parks (MNP) agent are more favorable to and supportive of the park conservation. People living in the park are supportive but are more divided. On the other hand, people living on the periphery of the park see conservation as more of a burden. Strategies like more equitable distribution of wealth, environment improvement and decentralization of power are discussed to achieve a more sustainable management plan based on community natural resources management. Short-term, medium, and long-term interventions from park authorities are needed to ensure the cooperation of local people in conservation endeavors. PMID:23494265

Aymoz, Benoît G P; Randrianjafy, Vololomboahangy R; Randrianjafy, Zarasoa J N; Khasa, Damase P

2013-10-01

281

Spatial variations in Eulemur fulvus rufus and Lepilemur mustelinus densities in Madagascar.  

PubMed

I present data on variations in Eulemur fulvus rufus and Lepilemur mustelinus densities as well as tree characteristics (height, diameter and stem frequency) between edge and interior forest habitats in southeastern Madagascar. Line transect surveys were conducted from June 2003 to November 2005 in edge and interior forest habitats in the Vohibola III Classified Forest. Although E. f. rufus densities were significantly lower in edge habitats than in interior habitats, density estimates for L. mustelinus did not differ significantly between habitats. Trees in edge habitats were significantly shorter, had smaller diameters and had lower stem frequencies (for those >25 cm in diameter) than trees in interior habitats. Spatial characteristics of food abundance and quality may explain lemur density patterns in Vohibola III. Low E. f. rufus densities may reduce seed dispersal in edge habitats, which has important consequences for the long-term viability of forest ecosystems in Madagascar. PMID:17170556

Lehman, Shawn M

2007-01-01

282

Historical demography of a wild lemur population ( Propithecus verreauxi ) in southwest Madagascar  

Microsoft Academic Search

The human colonization of Madagascar is associated with the extinction of numerous lemur species. However, the degree to which\\u000a humans have negatively influenced the historical population dynamics of extant lemur species is not well understood. This\\u000a study employs genetic and demographic analyses to estimate demographic parameters relating to the historical population dynamics\\u000a of a wild lemur population, Verreaux’s sifaka (Propithecus

Richard R. Lawler

2011-01-01

283

Neoproterozoic extension in the greater dharwar craton: A reevaluation of the "betsimisaraka suture" in madagascar  

USGS Publications Warehouse

The Precambrian shield of Madagascar is reevaluated with recently compiled geological data and new U-Pb sensitive high-resolution ion microprobe (SHRIMP) geochronology. Two Archean domains are recognized: the eastern Antongil-Masora domain and the central Antananarivo domain, the latter with distinctive belts of metamafic gneiss and schist (Tsaratanana Complex). In the eastern domain, the period of early crust formation is extended to the Paleo-Mesoarchean (3.32-3.15 Ga) and a supracrustal sequence (Fenerivo Group), deposited at 3.18 Ga and metamorphosed at 2.55 Ga, is identified. In the central domain, a Neoarchean period of high-grade metamorphism and anatexis that affected both felsic (Betsiboka Suite) and mafic gneisses (Tsaratanana Complex) is documented. We propose, therefore, that the Antananarivo domain was amalgamated within the Greater Dharwar Craton (India + Madagascar) by a Neoarchean accretion event (2.55-2.48 Ga), involving emplacement of juvenile igneous rocks, high-grade metamorphism, and the juxtaposition of disparate belts of mafic gneiss and schist (metagreenstones). The concept of the "Betsimisaraka suture" is dispelled and the zone is redefined as a domain of Neoproterozoic metasedimentary (Manampotsy Group) and metaigneous rocks (Itsindro-Imorona Suite) formed during a period of continental extension and intrusive igneous activity between 840 and 760 Ma. Younger orogenic convergence (560-520 Ma) resulted in east-directed overthrusting throughout south Madagascar and steepening with local inversion of the domain in central Madagascar. Along part of its length, the Manampotsy Group covers the boundary between the eastern and central Archean domains and is overprinted by the Angavo-Ifanadiana high-strain zone that served as a zone of crustal weakness throughout Cretaceous to Recent times.

Tucker, R.D.; Roig, J.-Y.; Delor, C.; Amlin, Y.; Goncalves, P.; Rabarimanana, M.H.; Ralison, A.V.; Belcher, R.W.

2011-01-01

284

Aye-aye population genomic analyses highlight an important center of endemism in northern Madagascar  

PubMed Central

We performed a population genomics study of the aye-aye, a highly specialized nocturnal lemur from Madagascar. Aye-ayes have low population densities and extensive range requirements that could make this flagship species particularly susceptible to extinction. Therefore, knowledge of genetic diversity and differentiation among aye-aye populations is critical for conservation planning. Such information may also advance our general understanding of Malagasy biogeography, as aye-ayes have the largest species distribution of any lemur. We generated and analyzed whole-genome sequence data for 12 aye-ayes from three regions of Madagascar (North, West, and East). We found that the North population is genetically distinct, with strong differentiation from other aye-ayes over relatively short geographic distances. For comparison, the average FST value between the North and East aye-aye populations—separated by only 248 km—is over 2.1-times greater than that observed between human Africans and Europeans. This finding is consistent with prior watershed- and climate-based hypotheses of a center of endemism in northern Madagascar. Taken together, these results suggest a strong and long-term biogeographical barrier to gene flow. Thus, the specific attention that should be directed toward preserving large, contiguous aye-aye habitats in northern Madagascar may also benefit the conservation of other distinct taxonomic units. To help facilitate future ecological- and conservation-motivated population genomic analyses by noncomputational biologists, the analytical toolkit used in this study is available on the Galaxy Web site. PMID:23530231

Perry, George H.; Louis, Edward E.; Ratan, Aakrosh; Bedoya-Reina, Oscar C.; Burhans, Richard C.; Lei, Runhua; Johnson, Steig E.; Schuster, Stephan C.; Miller, Webb

2013-01-01

285

Susceptibility to Yersinia pestis Experimental Infection in Wild Rattus rattus , Reservoir of Plague in Madagascar  

Microsoft Academic Search

In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague\\u000a challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between

C. Tollenaere; L. Rahalison; M. Ranjalahy; J.-M. Duplantier; S. Rahelinirina; S. Telfer; C. Brouat

2010-01-01

286

Social interactions and aggression among male Madagascar hissing cockroaches ( Gromphadorhina portentosa ) in groups (Dictyoptera: Blaberidae)  

Microsoft Academic Search

We studied agonistic interactions among male Madagascar hissing cockroaches,Gromphadorhina portentosa, in groups of five (low-density) or 10 (high-density) males. Consistent with previous studies of male pairs, we observed aggression (Abdomen Flick, Abdomen Push, Butt, Lunge), submission (Crouch, Retreat), and noncontact behavior (Abdominal Extension, Abdomen Thrash, Agonistic Hiss, Stilt). Males at both densities performed all acts. However, males in the high-density

Deborah C. Clark; Allen J. Moore

1994-01-01

287

Three new species of the genus Exphora Signoret, 1860 (Hemiptera, Fulgoromorpha, Tropiduchidae) from Madagascar.  

PubMed

Three new species of the genus Exphora Signoret, 1860 (Hemiptera, Fulgoromorpha: Tropiduchidae) are described from Madagascar: E. constanti sp. n., E. stroinskii sp. n. and E. ambatolaonaensis sp. n. The male genitalia are described for the first time in this genus. The male genitalia, head and fore wing of the new species are illustrated with photos of habitus provided. Key to the known species of Exphora is given. PMID:25781773

Junkiert, ?ukasz; Walczak, Marcin

2015-01-01

288

Searching for the Oldest Baobab of Madagascar: Radiocarbon Investigation of Large Adansonia rubrostipa Trees.  

PubMed

We extended our research on the architecture, growth and age of trees belonging to the genus Adansonia, by starting to investigate large individuals of the most widespread Malagasy species. Our research also intends to identify the oldest baobabs of Madagascar. Here we present results of the radiocarbon investigation of the two most representative Adansonia rubrostipa (fony baobab) specimens, which are located in south-western Madagascar, in the Tsimanampetsotse National Park. We found that the fony baobab called "Grandmother" consists of 3 perfectly fused stems of different ages. The radiocarbon date of the oldest sample was found to be 1136 ± 16 BP. We estimated that the oldest part of this tree, which is mainly hollow, has an age close to 1,600 yr. This value is comparable to the age of the oldest Adansonia digitata (African baobab) specimens. By its age, the Grandmother is a major candidate for the oldest baobab of Madagascar. The second investigated specimen, called the "polygamous baobab", consists of 6 partially fused stems of different ages. According to dating results, this fony baobab is 1,000 yr old. This research is the first investigation of the structure and age of Malagasy baobabs. PMID:25806967

Patrut, Adrian; von Reden, Karl F; Danthu, Pascal; Leong Pock-Tsy, Jean-Michel; Patrut, Roxana T; Lowy, Daniel A

2015-01-01

289

Biodiversity conservation and drug discovery: Can they be combined? The Suriname and Madagascar experiences  

PubMed Central

The approach to new drugs through natural products has proved to be the single most successful strategy for the discovery of new drugs, but in recent years its use has been deemphasized by many pharmaceutical companies in favor of approaches based on combinatorial chemistry and genomics, among others. Drug discovery from natural sources requires continued access to plant, marine, and microbial biomass, and so the preservation of tropical rainforests is an important part of our drug discovery program. Sadly, many of the tropical forests of the world are under severe environmental pressure, and deforestation is a serious problem in most tropical countries. One way to combat this loss is to demonstrate their value as potential sources of new pharmaceutical or agrochemical products. As part of an effort to integrate biodiversity conservation and drug discovery with economic development, we initiated an International Cooperative biodiversity Group (ICBG) to discover potential pharmaceuticals from the plant biodiversity of Suriname and Madagascar. The Group, established with funding from agencies of the United States government, involved participants from the USA, Suriname, and Madagascar. The basic approach was to search for bioactive plants in the Suriname and Malagasy flora, and to isolate their bioactive constituents by the best available methods, but the work included capacity building as well as research. Progress on this project will be reported, drawing on results obtained from the isolation of bioactive natural products from Suriname and Madagascar. The benefits of this general approach to biodiversity and drug discovery will also be discussed. PMID:20161050

Cao, Shugeng; Kingston, David G. I.

2009-01-01

290

Searching for the Oldest Baobab of Madagascar: Radiocarbon Investigation of Large Adansonia rubrostipa Trees  

PubMed Central

We extended our research on the architecture, growth and age of trees belonging to the genus Adansonia, by starting to investigate large individuals of the most widespread Malagasy species. Our research also intends to identify the oldest baobabs of Madagascar. Here we present results of the radiocarbon investigation of the two most representative Adansonia rubrostipa (fony baobab) specimens, which are located in south-western Madagascar, in the Tsimanampetsotse National Park. We found that the fony baobab called “Grandmother” consists of 3 perfectly fused stems of different ages. The radiocarbon date of the oldest sample was found to be 1136 ± 16 BP. We estimated that the oldest part of this tree, which is mainly hollow, has an age close to 1,600 yr. This value is comparable to the age of the oldest Adansonia digitata (African baobab) specimens. By its age, the Grandmother is a major candidate for the oldest baobab of Madagascar. The second investigated specimen, called the “polygamous baobab”, consists of 6 partially fused stems of different ages. According to dating results, this fony baobab is 1,000 yr old. This research is the first investigation of the structure and age of Malagasy baobabs. PMID:25806967

Patrut, Adrian; von Reden, Karl F.; Danthu, Pascal; Leong Pock-Tsy, Jean-Michel; Patrut, Roxana T.; Lowy, Daniel A.

2015-01-01

291

Conservation education in Madagascar: three case studies in the biologically diverse island-continent.  

PubMed

Few Malagasy children and adults are aware of the rare and unique fauna and flora indigenous to their island-continent, including flagship lemur species. Even the Malagasy ancestral proverbs never mentioned lemurs, but these same proverbs talked about the now extinct hippopotamus. Madagascar's geography, history, and economic constraints contribute to severe biodiversity loss. Deforestation on Madagascar is reported to be over 100,000 ha/year, with only 10-15% of the island retaining natural forest [Green & Sussman, 1990]. Educating children, teacher-training, and community projects about environmental and conservation efforts to protect the remaining natural habitats of endangered lemur species provide a basis for long-term changes in attitudes and practices. Case studies of three conservation education projects located in different geographical regions of Madagascar, Centre ValBio, Madagacar Wildlife Conservation Alaotra Comic Book Project, and The Ako Book Project, are presented together with their ongoing stages of development, assessment, and outcomes. We argue that while nongovernmental organizational efforts are and will be very important, the Ministry of Education urgently needs to incorporate biodiversity education in the curriculum at all levels, from primary school to university. PMID:20039330

Dolins, Francine L; Jolly, Alison; Rasamimanana, Hantanirina; Ratsimbazafy, Jonah; Feistner, Anna T C; Ravoavy, Florent

2010-05-01

292

The Hippoboscidae (Insecta: Diptera) from Madagascar, with new records from the “Parc National de Midongy Befotaka”  

PubMed Central

The Hippoboscidae or “louse-flies” is a family of pupiparous Diptera, which in their adult stage are ectoparasites of mammals and birds. This paper presents a comprehensive review of Malagasy Hippoboscidae. In total, amongst the 213 species of this family known worldwide, 14 have been reported in Madagascar, among which six are considered as endemic to the Malagasy region. In addition, data are presented from a collection of 17 Hippoboscidae obtained from seven species of forest-dwelling birds in the “Parc National de Midongy Befotaka”, southeastern Madagascar, in 2003. The flies in this collection belong to three different species: Icosta malagasii (one), Ornithoica podicipis (ten) and Ornithoctona laticornis (six). The two former species were previously only known from single specimens in museum collections; the later species is distributed across much of the Afrotropical region and the records presented herein are the first for Madagascar. All the seven bird species are new hosts for hippoboscids. We present the first description of the male of Icosta malagasii. An illustrated dichotomous determination key of the 14 Malagasy species, based on morphological criteria only, is presented. PMID:21678788

Rahola, N.; Goodman, S.M.; Robert, V.

2011-01-01

293

Diversification of an emerging pathogen in a biodiversity hotspot: Leptospira in endemic small mammals of Madagascar.  

PubMed

Biodiversity hotspots and associated endemism are ideal systems for the study of parasite diversity within host communities. Here, we investigated the ecological and evolutionary forces acting on the diversification of an emerging bacterial pathogen, Leptospira spp., in communities of endemic Malagasy small mammals. We determined the infection rate with pathogenic Leptospira in 20 species of sympatric rodents (subfamily Nesomyinae) and tenrecids (family Tenrecidae) at two eastern humid forest localities. A multilocus genotyping analysis allowed the characterization of bacterial diversity within small mammals and gave insights into their genetic relationships with Leptospira infecting endemic Malagasy bats (family Miniopteridae and Vespertilionidae). We report for the first time the presence of pathogenic Leptospira in Malagasy endemic small mammals, with an overall prevalence of 13%. In addition, these hosts harbour species of Leptospira (L. kirschneri, L. borgpetersenii and L. borgpetersenii group B) which are different from those reported in introduced rats (L. interrogans) on Madagascar. The diversification of Leptospira on Madagascar can be traced millions of years into evolutionary history, resulting in the divergence of endemic lineages and strong host specificity. These observations are discussed in relation to the relative roles of endemic vs. introduced mammal species in the evolution and epidemiology of Leptospira on Madagascar, specifically how biodiversity and biogeographical processes can shape community ecology of an emerging pathogen and lead to its diversification within native animal communities. PMID:24784171

Dietrich, Muriel; Wilkinson, David A; Soarimalala, Voahangy; Goodman, Steven M; Dellagi, Koussay; Tortosa, Pablo

2014-06-01

294

The epidemiological transition in Antananarivo, Madagascar: an assessment based on death registers (1900–2012)  

PubMed Central

Background Madagascar today has one of the highest life expectancies in sub-Saharan Africa, despite being among the poorest countries in the continent. There are relatively few detailed accounts of the epidemiological transition in this country due to the lack of a comprehensive death registration system at the national level. However, in Madagascar’s capital city, death registration was established around the start of the 20th century and is now considered virtually complete. Objective We provide an overview of trends in all-cause and cause-specific mortality in Antananarivo to document the timing and pace of the mortality decline and the changes in the cause-of-death structure. Design Death registers covering the period 1976–2012 were digitized and the population at risk of dying was estimated from available censuses and surveys. Trends for the period 1900–1976 were partly reconstructed from published sources. Results The crude death rate stagnated around 30‰ until the 1940s in Antananarivo. Mortality declined rapidly after the World War II and then resurged again in the 1980s as a result of the re-emergence of malaria and the collapse of Madagascar’s economy. Over the past 30 years, impressive gains in life expectancy have been registered thanks to the unabated decline in child mortality, despite political instability, a lasting economic crisis and the persistence of high rates of chronic malnutrition. Progress in adult survival has been more modest because reductions in infectious diseases and diseases of the respiratory system have been partly offset by increases in cardiovascular diseases, neoplasms, and other diseases, particularly at age 50 years and over. Conclusions The transition in Antananarivo has been protracted and largely dependent on anti-microbial and anti-parasitic medicine. The capital city now faces a double burden of communicable and non-communicable diseases. The ongoing registration of deaths in the capital generates a unique database to evaluate the performance of the health system and measure intervention impacts. PMID:24848650

Masquelier, Bruno; Waltisperger, Dominique; Ralijaona, Osée; Pison, Gilles; Ravélo, Arsène

2014-01-01

295

The re-stocking of captive-bred ruffed lemurs (Varecia variegata variegata) into the Betampona Reserve, Madagascar: methodology and recommendations  

Microsoft Academic Search

Since November 1997 the Madagascar Fauna Group has released 13 captive-bred black and white ruffed lemurs (Varecia variegata variegata) into the Betampona Reserve in eastern Madagascar. The release programme has three major aims: (1) to assess the ability of captive-bred V. v. variegata to adapt to life in their natural habitat; (2) to investigate the contribution that such a release

Adam Britt; Charles Welch; Andrea Katz; Bernard Iambana; Ingrid Porton; Randall Junge; Graham Crawford; Cathy Williams; David Haring

2004-01-01

296

Long-term survival despite low genetic diversity in Blackwell Publishing Ltd the critically endangered Madagascar fish-eagle  

E-print Network

The critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) is considered to be one of the rarest birds of prey globally and at significant risk of extinction. In the most recent census, only 222 adult individuals were recorded with an estimated total breeding population of no more than 100–120 pairs. Here, levels of Madagascar fish-eagle population genetic diversity based on 47 microsatellite loci were compared with its sister species, the African fish-eagle (Haliaeetus vocifer), and 16 of these loci were also characterized in the white-tailed eagle (Haliaeetus albicilla) and the bald eagle (Haliaeetus leucocephalus). Overall, extremely low genetic diversity was observed in the Madagascar fish-eagle compared to other surveyed Haliaeetus species. Determining whether this low diversity is the result of a recent bottleneck or a more historic event has important implications for their conservation. Using a Bayesian coalescent-based method, we show that Madagascar fish-eagles have maintained a small effective population size for hundreds to thousands of years and that its low level of neutral genetic diversity is not the result of a recent bottleneck. Therefore, efforts made to prevent Madagascar fish-eagle extinction should place

Jeff A. Johnson; Ruth E. Tingay; Melanie Culver; Frank Hailer; Michèle L. Clarke; David P. Mindell

297

Proximal and distal styles of pegmatite-related metasomatic emerald mineralization at Ianapera, southern Madagascar  

NASA Astrophysics Data System (ADS)

The Ianapera emerald deposit is located in the Neoproterozoic Vohibory Block of southern Madagascar. The local geology consists of intercalated migmatitic gneissic units and calcareous metasedimentary rocks, containing boudinaged metamorphosed mafic/ultramafic lenses, all intruded by pegmatite veins. These units occur near the hinge of the tightly folded Ianapera antiform, within a few kilometers of the Ampanihy shear zone. Emerald mineralization is hosted by metasomatic phlogopite veins, and bodies developed within the mafic/ultramafic rocks. Based on field and textural relationships, we distinguish proximal and distal styles of mineralization. Proximal mineralization occurs at the contact of pegmatite veins with mafic/ultramafic units; in the distal style, pegmatites are not observed. Three types of emeralds could be distinguished, mainly on the basis of color and mineral zoning. Some of these emeralds have the most Al-depleted and Cr-rich composition ever recorded. Another characteristic feature to the Ianapera deposit and, to our knowledge, yet unreported, is the association of some emeralds with scapolite in metasomatised mafic rocks. Mineral inclusions are common in most emeralds and include phlogopite, carbonates, barite, K-feldspar, quartz, pyrite, zircon, monazite, bastnaesite, phenakite, plus Fe and Cr oxides. However, feldspar and rare earth element-bearing minerals occur predominantly in proximal emeralds, which also have a more incompatible trace-element signature than distal emeralds. We propose a model related to syn- to post-tectonic magmatic-hydrothermal activity. Pegmatitic bodies intruded units of the Ianapera antiform probably during tectonic relaxation. Exsolution of fluids rich in halogens and incompatible elements from the cooling pegmatites caused hydrothermal metasomatism of Cr-bearing mafic/ultramafic rocks in direct contact with the pegmatites. Local fracturing favored fluid infiltration, permitting the formation of distal mineralization. Emerald composition was controlled by the chemistry of the host rock. The presence of carbonate mineral inclusions in the emeralds and the high F-activity indicated by elevated F-contents in newly formed minerals suggest transport of Be as a fluoride-carbonate complex. It seems likely that beryl formation was triggered by precipitation of F-rich phlogopite, which removed the complexing ligand from the fluid.

Andrianjakavah, Prosper Rakotovao; Salvi, Stefano; Béziat, Didier; Rakotondrazafy, Michel; Giuliani, Gaston

2009-10-01

298

Molecular characterization of recombinant T1, a non-allergenic periwinkle (Catharanthus roseus) protein, with sequence similarity to the Bet v 1 plant allergen family.  

PubMed Central

More than 25% of the population suffer from Type I allergy, an IgE-mediated hypersensitivity disease. Allergens with homology to the major birch ( Betula verrucosa ) pollen allergen, Bet v 1, belong to the most potent elicitors of IgE-mediated allergies. T1, a cytokinin-inducible cytoplasmic periwinkle ( Catharanthus roseus ) protein, with significant sequence similarity to members of the Bet v 1 plant allergen family, was expressed in Escherichia coli. Recombinant T1 (rT1) did not react with IgE antibodies from allergic patients, and failed to induce basophil histamine release and immediate-type skin reactions in Bet v 1-allergic patients. Antibodies raised against purified rT1 could be used for in situ localization of natural T1 by immunogold electron microscopy, but did not cross-react with most of the Bet v 1-related allergens. CD analysis showed significant differences regarding secondary structure and thermal denaturation behaviour between rT1 and recombinant Bet v 1, suggesting that these structural differences are responsible for the different allergenicity of the proteins. T1 represents a non-allergenic member of the Bet v 1 family that may be used to study structural requirements of allergenicity and to engineer hypo-allergenic plants by replacing Bet v 1-related allergens for primary prevention of allergy. PMID:12656672

Laffer, Sylvia; Hamdi, Said; Lupinek, Christian; Sperr, Wolfgang R; Valent, Peter; Verdino, Petra; Keller, Walter; Grote, Monika; Hoffmann-Sommergruber, Karin; Scheiner, Otto; Kraft, Dietrich; Rideau, Marc; Valenta, Rudolf

2003-01-01

299

Isolation and structural elucidation of cytotoxic compounds from the root bark of Diospyros quercina (Baill.) endemic to Madagascar  

PubMed Central

Objective To isolate and characterize the cytotoxic compounds from Diospyros quercina (Baill.) G.E. Schatz & Lowry (Ebenaceae). Methods An ethno-botanical survey was conducted in the south of Madagascar from July to August 2010. Bio-guided fractionation assay was carried out on the root bark of Diospyros quercina, using cytotoxicity bioassay on murine P388 leukemia cell lines as model. The structures of the cytotoxic compounds were elucidated by 1D and 2D NMR spectroscopy and mass spectrometry. Results Biological experiments resulted in the isolation of three bioactive pure compounds (named TR-21, TR-22, and TR-23) which exhibited very good in vitro cytotoxic activities with the IC50 values of (0.017?5±0.0060) µg/mL, (0.089±0.005) µg/mL and (1.027±0.070) µg/mL respectively. Thus, they support the claims of traditional healers and suggest the possible correlation between the chemical composition of this plant and its wide use in Malagasy folk medicine to treat cancer. Conclusions The ability of isolated compounds in this study to inhibit cell growth may represent a rational explanation for the use of Diospyros quercina root bark in treating cancer by Malagasy traditional healers. Further studies are, therefore, necessary to evaluate the in vivo anti-neoplastic activity of these cytotoxic compounds as effective anticancer drugs. PMID:25182433

Ruphin, Fatiany Pierre; Baholy, Robijaona; Emmanuel, Randrianarivo; Amelie, Raharisololalao; Martin, Marie-Therese; Koto–te-Nyiwa, Ngbolua

2014-01-01

300

Description and analysis of the poultry trading network in the Lake Alaotra region, Madagascar: implications for the surveillance and control of Newcastle disease.  

PubMed

Madagascar's 36.5-million-head poultry industry holds a foremost place in its economy and the livelihood of its people. Unfortunately, regular Newcastle disease outbreaks associated with high mortality causes high losses for smallholders and threatens their livelihood. Therefore, Madagascar is seeking concrete, achievable and sustainable methods for the surveillance and the control of Newcastle disease. In this paper, we present and analyze the results of a field study conducted in Madagascar between December 2009 and December 2010. The study area was the Lac Alaotra region, a landlocked area in the north-eastern part of the country's center. Poultry trading is suspected of playing a major role in the spread of avian diseases, especially in developing countries characterized by many live-bird markets and middlemen. Therefore, the goals of our study were to: (i) describe and analyze smallholders' poultry trading network in the Lake Alaotra region using social network analysis; (ii) assess the role of the network in the spread of Newcastle disease; and (iii) propose the implementation of a targeted disease surveillance based on the characteristics of the poultry trading network. We focused our field study on the harvesting of two data sets. The first is a complete description of the poultry trading network in the landlocked area of Lac Alaotra, including a description of the poultry movements between groups of villages. The second set of data measures the occurrence of outbreaks in the same area by combining a participatory approach with an event-based surveillance method. These data were used to determine the attributes of the network, and to statistically assess the association between the position of nodes and the occurrence of outbreaks. By using social network analysis techniques combined with a classification method and a logistic model, we finally identified 3 nodes (set of villages), of the 387 in the initial network, to focus on for surveillance and control in the Lac Alaotra area. This result is of primary importance in the ongoing efforts to effectively improve the wellbeing of people in the region. PMID:24681223

Rasamoelina-Andriamanivo, H; Duboz, R; Lancelot, R; Maminiaina, O F; Jourdan, M; Rakotondramaro, T M C; Rakotonjanahary, S N; de Almeida, R Servan; Rakotondravao; Durand, B; Chevalier, V

2014-07-01

301

Medicinal plants used by women from Agnalazaha littoral forest (Southeastern Madagascar)  

PubMed Central

Background The country of Madagascar is renowned for its high level of biodiversity and endemism, as well as the overwhelming pressures and threats placed on the natural resources by a growing population and climate change. Traditional medicine plays an important role in the daily lives of the Malagasy for various reasons including limited access to healthcare, limited markets and traditional values. The objective of this study was to assess the modern utitilization of the Agnalazaha Forest by the local population in Mahabo-Mananivo, Madagascar, for medicinal plants used by women, and to establish a list of medicinal plants used by women sourced from Agnalazaha Forest. Methods Ethnobotanical studies were conducted over a period of five months in 2010 to determine the diversity of medicinal plants used by women in the commune of Mahabo-Mananivo. In all, 498 people were interviewed, both male and female ranging age from 15 to over 60 years old. Results 152 medicinal plants used by local people were collected during the ethnobotanical studies. Among the recorded species, eight native species are widely used by women. These species are known for their therapeutic properties in treating placental apposition and complications during childbirth as well as tropical illnesses such as malaria, filariasis, and sexual diseases like gonorrhea and syphilis. Conclusions Littoral forests are rare ecosystems that are highly threatened on the island nation of Madagascar. Our investigation into the use of medicinal plants sourced from and around the Agnalazaha Forest by the women of Mahabo-Mananivo reinforces the need for this natural resource as a first line of health care for rural families. PMID:24188563

2013-01-01

302

Analysis of Patterns of Bushmeat Consumption Reveals Extensive Exploitation of Protected Species in Eastern Madagascar  

PubMed Central

Understanding the patterns of wild meat consumption from tropical forests is important for designing approaches to address this major threat to biodiversity and mitigate potential pathways for transmission of emerging diseases. Bushmeat consumption has been particularly poorly studied in Madagascar, one of the world's hottest biodiversity hotspots. Studying bushmeat consumption is challenging as many species are protected and researchers must consider the incentives faced by informants. Using interviews with 1154 households in 12 communes in eastern Madagascar, as well as local monitoring data, we investigated the importance of socio-economic variables, taste preference and traditional taboos on consumption of 50 wild and domestic species. The majority of meals contain no animal protein. However, respondents consume a wide range of wild species and 95% of respondents have eaten at least one protected species (and nearly 45% have eaten more than 10). The rural/urban divide and wealth are important predictors of bushmeat consumption, but the magnitude and direction of the effect varies between species. Bushmeat species are not preferred and are considered inferior to fish and domestic animals. Taboos have provided protection to some species, particularly the Endangered Indri, but we present evidence that this taboo is rapidly eroding. By considering a variety of potential influences on consumption in a single study we have improved understanding of who is eating bushmeat and why. Evidence that bushmeat species are not generally preferred meats suggest that projects which increase the availability of domestic meat and fish may have success at reducing demand. We also suggest that enforcement of existing wildlife and firearm laws should be a priority, particularly in areas undergoing rapid social change. The issue of hunting as an important threat to biodiversity in Madagascar is only now being fully recognised. Urgent action is required to ensure that heavily hunted species are adequately protected. PMID:22194787

Jenkins, Richard K. B.; Keane, Aidan; Rakotoarivelo, Andrinajoro R.; Rakotomboavonjy, Victor; Randrianandrianina, Felicien H.; Razafimanahaka, H. Julie; Ralaiarimalala, Sylvain R.; Jones, Julia P. G.

2011-01-01

303

[Prevalence of tobacco use and associated factors among teenage students in Madagascar].  

PubMed

The available data on the prevalence of tobacco use among teenagers in Madagascar are very limited. The aim of this study was to analyze tobacco-use behaviors among teenage pupils aged 12 to 18 living in urban and suburban areas of Madagascar and to identify the associated risk factors. A cross-sectional descriptive study was conducted as part of this research. Probabilistic multistage sampling was used to obtain a representative sample. Data were collected using an anonymous self-reported questionnaire and computer analyzed using SPSS 16. Correlation and logistic regression were used to analyze the risk factors. The results show that approximately one third of the 711 pupils (36.3%) included in the sample reported that they had tried tobacco. Among them, 25.2% were regular users. Nearly 10% had started smoking before the age of 14. Male adolescents were found to smoke twice as much as their female counterparts. The study found that the key factors associated with tobacco use include: male gender (Exp(B)=3,769(95%IC 2,579-5,509), urbanization (Exp(B) = 3,679, 95% IC 2,138-6,332), age, peer influence, a sense of insecurity at school, and the impact of the mass media (films, television). The study found that the family environment did not have a significant impact on tobacco use. To conclude, the prevalence of smoking among teenage pupils in Madagascar is a significant issue. This paper argues that it is important to understand the associated risk factors in order to develop a prevention program aimed at reversing the tobacco epidemic in schools. PMID:22370020

Befinoana, M; Razanamihaja, Noeline

2011-01-01

304

New Material of Beelzebufo, a Hyperossified Frog (Amphibia: Anura) from the Late Cretaceous of Madagascar  

PubMed Central

The extant anuran fauna of Madagascar is exceptionally rich and almost completely endemic. In recent years, many new species have been described and understanding of the history and relationships of this fauna has been greatly advanced by molecular studies, but very little is known of the fossil history of frogs on the island. Beelzebufo ampinga, the first named pre-Holocene frog from Madagascar, was described in 2008 on the basis of numerous disarticulated cranial and postcranial elements from the Upper Cretaceous (Maastrichtian) Maevarano Formation of Madagascar. These specimens documented the presence of a hyperossified taxon that differed strikingly from extant Malagasy frogs in its large size and heavy coarse cranial exostosis. Here we describe and analyse new, articulated, and more complete material of the skull, vertebral column, and hind limb, as well as additional isolated elements discovered since 2008. ?CT scans allow a detailed understanding of both internal and external morphology and permit a more accurate reconstruction. The new material shows Beelzebufo to have been even more bizarre than originally interpreted, with large posterolateral skull flanges and sculptured vertebral spine tables. The apparent absence of a tympanic membrane, the strong cranial exostosis, and vertebral morphology suggest it may have burrowed during seasonally arid conditions, which have been interpreted for the Maevarano Formation from independent sedimentological and taphonomic evidence. New phylogenetic analyses, incorporating both morphological and molecular data, continue to place Beelzebufo with hyloid rather than ranoid frogs. Within Hyloidea, Beelzebufo still groups with the South American Ceratophryidae thus continuing to pose difficulties with both biogeographic interpretations and prior molecular divergence dates. PMID:24489877

Evans, Susan E.; Groenke, Joseph R.; Jones, Marc E. H.; Turner, Alan H.; Krause, David W.

2014-01-01

305

Convergent evolution of chemical defense in poison frogs and arthropod prey between Madagascar and the Neotropics  

PubMed Central

With few exceptions, aposematically colored poison frogs sequester defensive alkaloids, unchanged, from dietary arthropods. In the Neotropics, myrmicine and formicine ants and the siphonotid millipede Rhinotus purpureus are dietary sources for alkaloids in dendrobatid poison frogs, yet the arthropod sources for Mantella poison frogs in Madagascar remained unknown. We report GC-MS analyses of extracts of arthropods and microsympatric Malagasy poison frogs (Mantella) collected from Ranomafana, Madagascar. Arthropod sources for 11 “poison frog” alkaloids were discovered, 7 of which were also detected in microsympatric Mantella. These arthropod sources include three endemic Malagasy ants, Tetramorium electrum, Anochetus grandidieri, and Paratrechina amblyops (subfamilies Myrmicinae, Ponerinae, and Formicinae, respectively), and the pantropical tramp millipede R. purpureus. Two of these ant species, A. grandidieri and T. electrum, were also found in Mantella stomachs, and ants represented the dominant prey type (67.3% of 609 identified stomach arthropods). To our knowledge, detection of 5,8-disubstituted (ds) indolizidine iso-217B in T. electrum represents the first izidine having a branch point in its carbon skeleton to be identified from ants, and detection of 3,5-ds pyrrolizidine 251O in A. grandidieri represents the first ponerine ant proposed as a dietary source of poison frog alkaloids. Endemic Malagasy ants with defensive alkaloids (with the exception of Paratrechina) are not closely related to any Neotropical species sharing similar chemical defenses. Our results suggest convergent evolution for the acquisition of defensive alkaloids in these dietary ants, which may have been the critical prerequisite for subsequent convergence in poison frogs between Madagascar and the Neotropics. PMID:16087888

Clark, Valerie C.; Raxworthy, Christopher J.; Rakotomalala, Valérie; Sierwald, Petra; Fisher, Brian L.

2005-01-01

306

Tectonic significance of granitoid plutons from the Andasibe paragneiss belt, east-central Madagascar  

NASA Astrophysics Data System (ADS)

The understanding of the crustal evolution of the central Madagascar is of major significance in the study of the Precambrian basement of Madagascar and the greater Gondwana supercontinent. The study area, known as Andasibe paragneiss defines a fold belt that stretches from Ambatondrazaka to Soavina area in eastern Madagascar and is intruded by extensive granitoid intrusions. The western part of Andasibe paragneiss lies within the crustal scale Angavo shear zone, and is characterized by fine to medium-grained foliated paragneiss, which also include biotite-hornblende gneiss, migmatitic quartzofeldspathic gneiss, sillimanite-bearing gneiss, garnet-bearing gneiss, graphitic gneiss intercalates with schist, quartzite, muscovite-bearing gneiss and marble. Three samples of granitoid plutons intruding the Andasibe paragneiss yielded isotope dilution-thermal ionization mass spectrometry (ID-TIMS) U-Pb zircon ages of 801.2×3.8Ma, 776.5×4.4Ma and 772.1×4.2Ma. These dates are interpreted to represent the crystallization ages of these rocks and are comparable to other reported U-Pb emplacement ages for granitoid plutons within and along the north-central margin of the Angavo shear zone, which are suggested to be related to ca. 820 Ma successor-arc plutonism. These granitoids pre-dates the Angavo shear zone and folds affecting the plutons foliation are believed to have formed during the East-African Orogen, which in this part of the Malagasy Precambrian basement, is considered to have associated with Neoproterozoic extensive magmatism ca. 820 Ma to 540 Ma.

Raharimahefa, T.

2013-12-01

307

Comparison of marine spatial planning methods in Madagascar demonstrates value of alternative approaches.  

PubMed

The Government of Madagascar plans to increase marine protected area coverage by over one million hectares. To assist this process, we compare four methods for marine spatial planning of Madagascar's west coast. Input data for each method was drawn from the same variables: fishing pressure, exposure to climate change, and biodiversity (habitats, species distributions, biological richness, and biodiversity value). The first method compares visual color classifications of primary variables, the second uses binary combinations of these variables to produce a categorical classification of management actions, the third is a target-based optimization using Marxan, and the fourth is conservation ranking with Zonation. We present results from each method, and compare the latter three approaches for spatial coverage, biodiversity representation, fishing cost and persistence probability. All results included large areas in the north, central, and southern parts of western Madagascar. Achieving 30% representation targets with Marxan required twice the fish catch loss than the categorical method. The categorical classification and Zonation do not consider targets for conservation features. However, when we reduced Marxan targets to 16.3%, matching the representation level of the "strict protection" class of the categorical result, the methods show similar catch losses. The management category portfolio has complete coverage, and presents several management recommendations including strict protection. Zonation produces rapid conservation rankings across large, diverse datasets. Marxan is useful for identifying strict protected areas that meet representation targets, and minimize exposure probabilities for conservation features at low economic cost. We show that methods based on Zonation and a simple combination of variables can produce results comparable to Marxan for species representation and catch losses, demonstrating the value of comparing alternative approaches during initial stages of the planning process. Choosing an appropriate approach ultimately depends on scientific and political factors including representation targets, likelihood of adoption, and persistence goals. PMID:22359534

Allnutt, Thomas F; McClanahan, Timothy R; Andréfouët, Serge; Baker, Merrill; Lagabrielle, Erwann; McClennen, Caleb; Rakotomanjaka, Andry J M; Tianarisoa, Tantely F; Watson, Reg; Kremen, Claire

2012-01-01

308

Geology, petrology and isotope geochemistry of massif-type anorthosites from southwest Madagascar  

Microsoft Academic Search

Four massif-type anorthosite bodies 25–100?km2 in area occur within high-pressure granulite facies supracrustal gneisses in southwestern Madagascar. Two of these bodies\\u000a (Ankafotia and Saririaky) appear to have been pulled apart by 40?km in a ductile shear zone, but structural features such\\u000a as sub-vertical stretching lineations indicate an origin by intense west-directed flattening and pure shear. Country rocks\\u000a (Graphite Series) include

Lewis D. Ashwal; Michael A. Hamilton; Vincent P. I. Morel; Roger A. Rambeloson

1998-01-01

309

Descriptions and biological notes on three unusual mantellid tadpoles (Amphibia: Anura: Mantellidae) from southeastern Madagascar  

USGS Publications Warehouse

The morphologies of three unusual tadpoles from slow-flowing, sandy-bottomed, rain forest streams in southeastern Madagascar are described. The large oral apparatus of the tadpole of Boophis picturatus Glaw, Vences, Andreone, and Vallan, 2001 lacks all keratinized structures and has an elaborately-folded lower labium with five, radially oriented, flattopped ridges. The tadpole of Mantidactylus guttulatus (Boulenger, 1881) lacks all keratinized mouthparts and has three immense papillae where the upper jaw normally occurs. The tadpole of Mantidactylus lugubris (Dumeril, 1853) has an ornate oral apparatus involving greatly hypertrophied derivatives of jaw serrations and unique structures on the lower labium that resemble labial teeth.

Altig, R.; McDiarmid, R.W.

2006-01-01

310

Antiproliferative Cardenolides of an Elaeodendron sp. from the Madagascar Rain Forest  

PubMed Central

Bioassay-guided fractionation of an ethanol extract obtained from the Madagascar plant Elaeodendron sp. led to the isolation of two new cardenolides, elaeodendrosides T and U (1 and 2). The structures of the new compounds were elucidated using 1D and 2D NMR experiments, and mass spectrometry. Compounds 1, 3, 4, and 5 showed significant antiproliferative activity against A2780 human ovarian cancer cells with IC50 values of 0.085, 0.019, 0.19, and 0.10 µM, respectively, while compounds 2 and 6 were less active. PMID:17547460

Cao, Shugeng; Brodie, Peggy J.; Miller, James S.; Ratovoson, Fidy; Callmander, Martin W.; Randrianasolo, Sennen; Rakotobe, Etienne; Rasamison, Vincent E.; Suh, Edward M.; TenDyke, Karen; Kingston, David G. I.

2008-01-01

311

Lead (pb) contamination of self-supply groundwater systems in coastal madagascar and predictions of blood lead levels in exposed children.  

PubMed

Thousands of households in coastal Madagascar rely on locally manufactured pitcher-pump systems to provide water for drinking, cooking, and household use. These pumps typically include components made from lead (Pb). In this study, concentrations of Pb in water were monitored at 18 household pitcher pumps in the city of Tamatave over three sampling campaigns. Concentrations of Pb frequently exceeded the World Health Organization's provisional guideline for drinking water of 10 ?g/L. Under first-draw conditions (i.e., after a pump had been inactive for 1 h), 67% of samples analyzed were in excess of 10 ?g/L Pb, with a median concentration of 13 ?g/L. However, flushing the pump systems before collecting water resulted in a statistically significant (p < 0.0001) decrease in Pb concentrations: 35% of samples collected after flushing exceeded 10 ?g/L, with a median concentration of 9 ?g/L. Based on measured Pb concentrations, a biokinetic model estimates that anywhere from 15% to 70% of children living in households with pitcher pumps may be at risk for elevated blood lead levels (>5 ?g/dL). Measured Pb concentrations in water were not correlated at statistically significant levels with pump-system age, well depth, system manufacturer, or season of sample collection; only the contact time (i.e., flushed or first-draw condition) was observed to correlate significantly with Pb concentrations. In two of the 18 systems, Pb valve weights were replaced with iron, which decreased the observed Pb concentrations in the water by 57-89% in one pump and by 89-96% in the other. Both systems produced samples exclusively below 10 ?g/L after substitution. Therefore, relatively straightforward operational changes on the part of the pump-system manufacturers and pump users might reduce Pb exposure, thereby helping to ensure the continued sustainability of pitcher pumps in Madagascar. PMID:25608177

Akers, D Brad; MacCarthy, Michael F; Cunningham, Jeffrey A; Annis, Jonathan; Mihelcic, James R

2015-03-01

312

Assessing natural resource use by forest-reliant communities in Madagascar using functional diversity and functional redundancy metrics.  

PubMed

Biodiversity plays an integral role in the livelihoods of subsistence-based forest-dwelling communities and as a consequence it is increasingly important to develop quantitative approaches that capture not only changes in taxonomic diversity, but also variation in natural resources and provisioning services. We apply a functional diversity metric originally developed for addressing questions in community ecology to assess utilitarian diversity of 56 forest plots in Madagascar. The use categories for utilitarian plants were determined using expert knowledge and household questionnaires. We used a null model approach to examine the utilitarian (functional) diversity and utilitarian redundancy present within ecological communities. Additionally, variables that might influence fluctuations in utilitarian diversity and redundancy--specifically number of felled trees, number of trails, basal area, canopy height, elevation, distance from village--were analyzed using Generalized Linear Models (GLMs). Eighteen of the 56 plots showed utilitarian diversity values significantly higher than expected. This result indicates that these habitats exhibited a low degree of utilitarian redundancy and were therefore comprised of plants with relatively distinct utilitarian properties. One implication of this finding is that minor losses in species richness may result in reductions in utilitarian diversity and redundancy, which may limit local residents' ability to switch between alternative choices. The GLM analysis showed that the most predictive model included basal area, canopy height and distance from village, which suggests that variation in utilitarian redundancy may be a result of local residents harvesting resources from the protected area. Our approach permits an assessment of the diversity of provisioning services available to local communities, offering unique insights that would not be possible using traditional taxonomic diversity measures. These analyses introduce another tool available to conservation biologists for assessing how future losses in biodiversity will lead to a reduction in natural resources and provisioning services from forests. PMID:21909413

Brown, Kerry A; Flynn, Dan F B; Abram, Nicola K; Ingram, J Carter; Johnson, Steig E; Wright, Patricia

2011-01-01

313

Analyse macro-sociolinguistique d'une situation de diglossie: le cas de Madagascar (A Macro-Sociolinguistic Analysis of a Diglossic Situation: The Case of Madagascar). Publication H-6.  

ERIC Educational Resources Information Center

The languages used in Madagascar are examined from the following perspectives: the linguistic varieties and functions socially recognized at the community level; the oppositions and complementarities that have become established between languages in contact; and the speakers' attitudes toward those varieties. The report focuses on the following…

Rambelo, Michel

314

Isolation of 22 new Haliaeetus microsatellite loci and their characterization in the critically endangered Madagascar fish-eagle (Haliaeetus vociferoides) and three other Haliaeetus eagle species  

USGS Publications Warehouse

We isolated a total of 22 microsatellite loci from two Haliaeetus species: the Madagascar fish-eagle (Haliaeetus vociferoides) and the bald eagle (Haliaeetus leucocephalus). Five loci were monomorphic in both the Madagascar fish-eagle (n = 24-43) and the bald eagle (n = 2-8) but were found to be polymorphic in other Haliaeetus species. Haliaeetus loci have proved useful for investigating gene flow in Haliaeetus and Aquila eagles. Ten loci were polymorphic in the critically endangered Madagascar fish-eagle and will be used to investigate the genetic population structure and mating system in this species. ?? 2007 The Authors.

Tingay, R.E.; Dawson, D.A.; Pandhal, J.; Clarke, M.L.; David, V.A.; Hailer, F.; Culver, M.

2007-01-01

315

First Large-Scale DNA Barcoding Assessment of Reptiles in the Biodiversity Hotspot of Madagascar, Based on  

E-print Network

First Large-Scale DNA Barcoding Assessment of Reptiles in the Biodiversity Hotspot of Madagascar of Braunschweig, Braunschweig, Germany Abstract Background: DNA barcoding of non-avian reptiles based species (including Squamata and Testudines) were sampled and successfully DNA barcoded. The new primer

316

Nouvelle découverte dans le Nord-Ouest de Madagascar et répartition géographique des espèces du genre Palaeopropithecus  

Microsoft Academic Search

During the field-work of 2003 in the Narinda peninsula in the Province of Mahajanga (North-West of Madagascar), we found a Palaeopropithecus of large size in the new cave “Raulin Zohy”. This fossil differs in morphology and size from the remains coming from other sites of this area and belonging to a new yet undescribed species. This discovery proves that two

Dominique Gommery; Sabine Tombomiadana; Frédérique Valentin; Beby Ramanivosoa; Raulin Bezoma

2004-01-01

317

Well-Being Is a Process of Becoming: Respondent-Led Research with Organic Farmers in Madagascar  

ERIC Educational Resources Information Center

Malagasy "players"--farmers, middle men, organic organisations and policy makers--see in export-orientated organic agriculture a way for Madagascar to build upon its historic export strengths: spices, essential oils, medicinal plants and tropical fruits. They point to the "de facto" organic status of most farming in the country and view organic…

Farnworth, Cathy Rozel

2009-01-01

318

Web gigantism in Darwin's bark spider, a new species from Madagascar (Araneidae: Caerostris) Matjaz Kuntner1,2  

E-print Network

Web gigantism in Darwin's bark spider, a new species from Madagascar (Araneidae: Caerostris) Matjaz, is grossly underestimated. Most species build large webs at forest edges, clearings, and gardens niche: casting its web across streams, rivers and lakes, so that the orb is suspended above water

Agnarsson, Ingi

319

A new species of Tophoderes Dejean from northern Madagascar with a checklist of the species (Coleoptera: Anthribidae) .  

PubMed

A new species, Tophoderes lidmilae Trýzna & Ba?a? sp. nov., from north Madagascar is described. Male genitalia are studied and illustrated and colour photographs of both sexes are added. A comparison with the most similar known species T. frenatus (Klug, 1833) is provided. A checklist of species of the Madagascan genus Tophoderes (Anthribidae: Anthribinae: Tophoderini) is provided.  PMID:25661210

Trýzna, Miloš; Ba?a?, Petr

2015-01-01

320

Madagascar hissing cockroach mite, Gromphadorholaelaps schaeferi, prevents fungal infection in its cockroach host: evidence for a mutualistic symbiosis  

Microsoft Academic Search

In this study, we provide the first evidence that the mite Gromphadorholaelaps schaeferi is beneficial to the Madagascar hissing cockroach Gromphadorhina portentosa by participating in a cleaning symbiosis and thus prolonging the life of its host. Gromphadorholaelaps schaeferi is a permanent resident of the cockroach and reduces mould levels by removing the food debris from the cockroach that acts as

Jay A. Yoder; Joshua B. Benoit; Brian Z. Hedges; Andrew J. Jajack; Lawrence W. Zettler

2012-01-01

321

Genetic aspects of communication during male-male competition in the Madagascar hissing cockroach: honest signalling of size  

Microsoft Academic Search

Male Madagascar hissing cockroaches, Gromphadorhina portentosa, engage in agonistic contests with other males and produce audible sounds or 'hisses' during these interactions. Hisses are used to maintain, rather than to establish, social relationships among males. The agonistic hisses of males are variable and could be used as signals to communicate size or competitive ability of an individual. In this study

Deborah C Clark; Allen J Moore

1995-01-01

322

The larva of Gromphadorholaelaps schaeferi Till (Acari: Laelapidae), an associate of the Madagascar hissing-cockroach, Gromphadorhina portentosa (Schaum)  

Microsoft Academic Search

A complete morphological description of the larva of Gromphadorholaelaps schaeferi Till, 1969,an associate of the Madagascar hissing-cockroach, Gromphadorhina portentosa (Schaum), is presented. The larva of this species is generally similar to larvae in other laelapid taxa, but the unusually long opisthonotal setae may be an adaptation to avoid intraspecific predation.

Beverly Swaim Gerdeman; J. S. H. Klompen; J. A. Yoder

1998-01-01

323

The impacts of forest clearance on lizard, small mammal and bird communities in the arid spiny forest, southern Madagascar  

Microsoft Academic Search

Madagascar is a global biodiversity hotspot threatened by forest loss, degradation and fragmentation, all of which are detrimental to the future survival of forest-dwelling organisms. For conservation purposes it is essential to determine how species respond to habitat disturbance, specifically deforestation. In this study we investigated the impacts of deforestation on three vertebrate communities, lizards, small mammals and birds, in

Dawn M. Scott; Daniel Brown; Simon Mahood; Buck Denton; Anastasia Silburn; Felix Rakotondraparany

2006-01-01

324

Trypomastigotes and potential flea vectors of the endemic rodents and the introduced Rattus rattus in the rainforests of Madagascar  

Microsoft Academic Search

Transmission of parasites and diseases may be one of the mechanisms for the displacement of native and endemic rodents of Madagascar (subfamily Nesomyinae) by the introduced Rattus rattus (subfamily Murinae). We studied the occurrence of trypomastigotes in rodents at several rainforest sites on the island. Examination of blood smears showed Trypanosoma lewisi-like trypomastigotes in 11.5% of the R. rattus (n

Juha Laakkonen; Steven M. Goodman; Jean-Bernard Duchemin; Jean-Marc Duplantier

2003-01-01

325

Widespread presence of the pathogenic fungus Batrachochytrium dendrobatidis in wild amphibian communities in Madagascar  

PubMed Central

Amphibian chytridiomycosis, an emerging infectious disease caused by the fungus Batrachochytrium dendrobatidis (Bd), has been a significant driver of amphibian declines. While globally widespread, Bd had not yet been reported from within Madagascar. We document surveys conducted across the country between 2005 and 2014, showing Bd's first record in 2010. Subsequently, Bd was detected in multiple areas, with prevalence reaching up to 100%. Detection of Bd appears to be associated with mid to high elevation sites and to have a seasonal pattern, with greater detectability during the dry season. Lineage-based PCR was performed on a subset of samples. While some did not amplify with any lineage probe, when a positive signal was observed, samples were most similar to the Global Panzootic Lineage (BdGPL). These results may suggest that Bd arrived recently, but do not exclude the existence of a previously undetected endemic Bd genotype. Representatives of all native anuran families have tested Bd-positive, and exposure trials confirm infection by Bd is possible. Bd's presence could pose significant threats to Madagascar's unique “megadiverse” amphibians. PMID:25719857

Bletz, Molly C.; Rosa, Gonçalo M.; Andreone, Franco; Courtois, Elodie A.; Schmeller, Dirk S.; Rabibisoa, Nirhy H. C.; Rabemananjara, Falitiana C. E.; Raharivololoniaina, Liliane; Vences, Miguel; Weldon, Ché; Edmonds, Devin; Raxworthy, Christopher J.; Harris, Reid N.; Fisher, Matthew C.; Crottini, Angelica

2015-01-01

326

Multiple colonization of Madagascar and Socotra by colubrid snakes: evidence from nuclear and mitochondrial gene phylogenies.  

PubMed Central

Colubrid snakes form a speciose group of unclarified phylogeny. Their almost cosmopolitan distribution could be interpreted as a product of plate-tectonic vicariance. We used sequences of the nuclear c-mos, the mitochondrial cytochrome b and the 16S rRNA genes in 41 taxa to elucidate the relationships between the endemic colubrid genera found in Madagascar and in the Socotra archipelago. The well-resolved trees indicate multiple origins of both the Malagasy and the Socotran taxa. The Malagasy genus Mimophis was nested within the Psammophiinae, and the Socotran Hemerophis was closely related to Old World representatives of the former genus Coluber. The remaining 14 genera of Malagasy colubrids formed a monophyletic sister group of the Socotran Ditypophis (together forming the Pseudoxyrhophiinae). Molecular-clock estimates place the divergence of Malagasy and Socotran colubrids from their non-insular sister groups into a time-frame between the Eocene and Miocene. Over-seas rafting is the most likely hypothesis for the origin of at least the Malagasy taxa. The discovery of a large monophyletic clade of colubrids endemic to Madagascar indicates a need for taxonomic changes. The relationship of this radiation to the Socotran Ditypophis highlights the potential of the Indian Ocean islands to act as an evolutionary reservoir for lineages that have become extinct in Africa and Asia. PMID:14728785

Nagy, Zoltán Tamás; Joger, Ulrich; Wink, Michael; Glaw, Frank; Vences, Miguel

2003-01-01

327

Seroprevalence of hepatitis C and associated risk factors in urban areas of Antananarivo, Madagascar  

PubMed Central

Background The risk factors for the transmission of HCV vary substantially between countries and geographic regions. The overall prevalence in south and east Africa region has been estimated to be 1.6% but limited information about the epidemiology of HCV infection in Madagascar is available Methods A cross-sectional survey for hepatitis C antibodies was conducted in 2,169 subjects of the general population of Antananarivo to determine seroprevalence of hepatitis C and associated risk factors. Results The overall seroprevalence was 1.2% (25/2,169). The prevalence did not differ significantly according to gender but it increased with age (Chi2 tendency test, p < 10-5). The variable history of hospitalization, previous therapeutic injections, dental treatment, intravenous drug use, and abnormal ALT and AST were statistically significantly related with the presence of HCV antibodies. No relationship with past history of blood transfusion was observed. Conclusion HCV prevalence in Madagascar seems to be similar to that in most other east African countries. Age appears to be an important risk factor. Iatrogenic causes of HCV transmission need to be further evaluated because all HCV cases had a history of receiving therapeutic injections and data suggested a cumulative effect in relation with therapeutic injections. PMID:18312652

Ramarokoto, Charles E; Rakotomanana, Fanjasoa; Ratsitorahina, Maherisoa; Raharimanga, Vaomalala; Razafindratsimandresy, Richter; Randremanana, Rindra; Rakoto-Andrianarivelo, Mala; Rousset, Dominique; Andrianaja, Voahangy; Richard, Vincent; Soares, Jean-Louis; Rabarijaona, Leon P

2008-01-01

328

Widespread presence of the pathogenic fungus Batrachochytrium dendrobatidis in wild amphibian communities in Madagascar.  

PubMed

Amphibian chytridiomycosis, an emerging infectious disease caused by the fungus Batrachochytrium dendrobatidis (Bd), has been a significant driver of amphibian declines. While globally widespread, Bd had not yet been reported from within Madagascar. We document surveys conducted across the country between 2005 and 2014, showing Bd's first record in 2010. Subsequently, Bd was detected in multiple areas, with prevalence reaching up to 100%. Detection of Bd appears to be associated with mid to high elevation sites and to have a seasonal pattern, with greater detectability during the dry season. Lineage-based PCR was performed on a subset of samples. While some did not amplify with any lineage probe, when a positive signal was observed, samples were most similar to the Global Panzootic Lineage (BdGPL). These results may suggest that Bd arrived recently, but do not exclude the existence of a previously undetected endemic Bd genotype. Representatives of all native anuran families have tested Bd-positive, and exposure trials confirm infection by Bd is possible. Bd's presence could pose significant threats to Madagascar's unique "megadiverse" amphibians. PMID:25719857

Bletz, Molly C; Rosa, Gonçalo M; Andreone, Franco; Courtois, Elodie A; Schmeller, Dirk S; Rabibisoa, Nirhy H C; Rabemananjara, Falitiana C E; Raharivololoniaina, Liliane; Vences, Miguel; Weldon, Ché; Edmonds, Devin; Raxworthy, Christopher J; Harris, Reid N; Fisher, Matthew C; Crottini, Angelica

2015-01-01

329

Invasion genetics of a human commensal rodent: the black rat Rattus rattus in Madagascar.  

PubMed

Studies focusing on geographical genetic patterns of commensal species and on human history complement each other and provide proxies to trace common colonization events. On Madagascar, the unintentional introduction and spread of the commensal species Rattus rattus by people may have left a living clue of human colonization patterns and history. In this study, we addressed this question by characterizing the genetic structure of natural populations of R. rattus using both microsatellites and mitochondrial sequences, on an extensive sampling across the island. Such data sets were analysed by a combination of methods using population genetics, phylogeography and approximate Bayesian computation. Our results indicated two introduction events to Madagascar from the same ancestral source of R. rattus, one in the extreme north of the island and the other further south. The latter was the source of a large spatial expansion, which may have initially started from an original point located on the southern coast. The inferred timing of introduction events-several centuries ago-is temporally congruent with the Arabian trade network in the Indian Ocean, which was flourishing from the middle of the first millennium. PMID:24975563

Brouat, C; Tollenaere, C; Estoup, A; Loiseau, A; Sommer, S; Soanandrasana, R; Rahalison, L; Rajerison, M; Piry, S; Goodman, S M; Duplantier, J-M

2014-08-01

330

Performance of a Receptive Language Test among Young Children in Madagascar  

PubMed Central

Language tests developed and validated in one country may lose their desired properties when translated for use in another, possibly resulting in misleading estimates of ability. Using Item Response Theory (IRT) methodology, we assess the performance of a test of receptive vocabulary, the U.S.-validated Peabody Picture Vocabulary Test-Third Edition (PPVT-III), when translated, adapted, and administered to children 3 to 10 years of age in Madagascar (N = 1372), in the local language (Malagasy). Though Malagasy is considered a single language, there are numerous dialects spoken in Madagascar. Our findings were that test scores were positively correlated with age and indicators of socio-economic status. However, over half (57/96) of items evidenced unexpected response variation and/or bias by local dialect spoken. We also encountered measurement error and reduced differentiation among person abilities when we used the publishers’ recommended stopping rules, largely because we lost the original item ordering by difficulty when we translated test items into Malagasy. Our results suggest that bias and testing inefficiency introduced from the translation of the PPVT can be significantly reduced with the use of methods based on IRT at both the pre-testing and analysis stages. We explore and discuss implications for cross-cultural comparisons of internationally recognized tests, such as the PPVT. PMID:25830221

Weber, Ann M.; Fernald, Lia C. H.; Galasso, Emanuela; Ratsifandrihamanana, Lisy

2015-01-01

331

Miocene benthic foraminifera from Nosy Makamby and Amparafaka, Mahajanga Basin, northwestern Madagascar  

NASA Astrophysics Data System (ADS)

Madagascar is well known for its fossil deposits and hosts one of the world's most important Upper Cretaceous terrestrial faunal sites (in the Mahajanga and Morondava Basins in the west and northwest of the island). Cenozoic marine fossils are also described from Madagascar, but these have received far less attention from the paleontological community, with most of this work dating from the 19th and early 20th centuries. Our study reports a new comprehensive microfossil assemblage from a Miocene sequence on the island of Nosy Makamby. After washing, sieving and sorting (?30 kg), twenty-five genera of foraminifera were identified including Alveolina, Ammodiscus, Ammonia, Archaias, Bolivina, Borelis, Cassidulina, Cyclammina, Cycloforina, Dentalina, Elphidium, Hauerina, Lagena, Lepidocyclina, Nodosaria, Nonion, Nonionella, Peneroplis, Pyrgo, Quinqueloculina, Rhabdammina, Spirillina, Spirolina, Spiroloculina and Triloculina. Ostracods are found in association with the foraminifera, as well as many other macroinvertebrate fossils (including bivalves, gastropods, and echinoids) in addition to vertebrate fossils. Together, the assemblage indicates that during the late Miocene, Nosy Makamby was a tropical, near-shore environment, probably similar to that seen today. Furthermore, the existence of epiphytic foraminiferans (e.g., Elphidium) suggests that sea-grass beds were likely present.

Ramihangihajason, Tolotra N.; Andrianavalona, Tsiory H.; Razafimbelo, Rachel; Rahantarisoa, Lydia; Ali, Jason R.; Samonds, Karen E.

2014-12-01

332

Impact of the high topography of Madagascar on the structure of the Findlater Jet  

NASA Astrophysics Data System (ADS)

The cross-equatorial flow over the western Indian Ocean, known as the Findlater Jet, plays an important role in the monsoonal circulation of the region. During the boreal summer, there is southerly flow across the equator that is concentrated along the East African highlands. During the boreal winter, there is a reversal in wind direction across the equator. Madagascar, the world's fourth largest island, with heights in excess of 1 km represents a significant obstacle to the flow whose impact on this jet has not been fully characterized. Here we use diagnostic tools developed to investigate atmospheric flow distortion by Greenland's high topography to study this interaction. We show that there is a bifurcation of the Findlater Jet by Madagascar during the boreal summer and localized tip jets at the island's northern and southern ends. During the boreal winter, the northern tip jet reverses direction and weakens, while the southern tip jet maintains its direction and magnitude. We show that rotational effects are important for these interactions but not dominant and result in an enhancement of the northern tip jet; while allowing for existence of the southern tip jet. As will also be shown, this flow distortion has impacts on the meteorology and oceanography of the region including the forcing of oceanic eddies in the Mozambique Channel, a modulation of the southward displacement of the Inter-Tropical Convergence Zone (ITCZ) and a splitting of the boreal summer cross-equatorial mass transport associated with the Findlater Jet into two branches.

Moore, G. W. K.

2013-05-01

333

Performance of a Receptive Language Test among Young Children in Madagascar.  

PubMed

Language tests developed and validated in one country may lose their desired properties when translated for use in another, possibly resulting in misleading estimates of ability. Using Item Response Theory (IRT) methodology, we assess the performance of a test of receptive vocabulary, the U.S.-validated Peabody Picture Vocabulary Test-Third Edition (PPVT-III), when translated, adapted, and administered to children 3 to 10 years of age in Madagascar (N = 1372), in the local language (Malagasy). Though Malagasy is considered a single language, there are numerous dialects spoken in Madagascar. Our findings were that test scores were positively correlated with age and indicators of socio-economic status. However, over half (57/96) of items evidenced unexpected response variation and/or bias by local dialect spoken. We also encountered measurement error and reduced differentiation among person abilities when we used the publishers' recommended stopping rules, largely because we lost the original item ordering by difficulty when we translated test items into Malagasy. Our results suggest that bias and testing inefficiency introduced from the translation of the PPVT can be significantly reduced with the use of methods based on IRT at both the pre-testing and analysis stages. We explore and discuss implications for cross-cultural comparisons of internationally recognized tests, such as the PPVT. PMID:25830221

Weber, Ann M; Fernald, Lia C H; Galasso, Emanuela; Ratsifandrihamanana, Lisy

2015-01-01

334

Key odorants in cured Madagascar vanilla beans (Vanilla planiforia) of differing bean quality.  

PubMed

The odor-active volatiles in Madagascar vanilla beans (Vanilla planiforia) of two grades, red whole beans as standard quality and cuts beans as substandard quality, were characterized by instrumental and sensory analyses. The higher contents of vanillin and ?-damascenone in red whole beans than in cuts beans respectively contributed to significant differences in the sweet and dried fruit-like notes, while the higher contents of guaiacol and 3-phenylpropanoic acid in cuts beans than in red whole beans respectively contributed to significant differences in the phenolic and metallic notes. A sensory evaluation to compare red whole beans and their reconstituted aroma characterized both samples as being similar, while in respect of the phenolic note, the reconstituted aroma significantly differed from the reconstituted aroma with guaiacol added at the concentration ratio of vanillin and guaiacol in cuts beans. It is suggested from these results that the concentration ratio of vanillin and guaiacol could be used as an index for the quality of Madagascar vanilla beans. PMID:23470767

Takahashi, Makoto; Inai, Yoko; Miyazawa, Norio; Kurobayashi, Yoshiko; Fujita, Akira

2013-01-01

335

In and out of Madagascar: Dispersal to Peripheral Islands, Insular Speciation and Diversification of Indian Ocean Daisy Trees (Psiadia, Asteraceae)  

PubMed Central

Madagascar is surrounded by archipelagos varying widely in origin, age and structure. Although small and geologically young, these archipelagos have accumulated disproportionate numbers of unique lineages in comparison to Madagascar, highlighting the role of waif-dispersal and rapid in situ diversification processes in generating endemic biodiversity. We reconstruct the evolutionary and biogeographical history of the genus Psiadia (Asteraceae), a plant genus with near equal numbers of species in Madagascar and surrounding islands. Analyzing patterns and processes of diversification, we explain species accumulation on peripheral islands and aim to offer new insights on the origin and potential causes for diversification in the Madagascar and Indian Ocean Islands biodiversity hotspot. Our results provide support for an African origin of the group, with strong support for non-monophyly. Colonization of the Mascarenes took place by two evolutionary distinct lineages from Madagascar, via two independent dispersal events, each unique for their spatial and temporal properties. Significant shifts in diversification rate followed regional expansion, resulting in co-occurring and phenotypically convergent species on high-elevation volcanic slopes. Like other endemic island lineages, Psiadia have been highly successful in dispersing to and radiating on isolated oceanic islands, typified by high habitat diversity and dynamic ecosystems fuelled by continued geological activity. Results stress the important biogeographical role for Rodrigues in serving as an outlying stepping stone from which regional colonization took place. We discuss how isolated volcanic islands contribute to regional diversity by generating substantial numbers of endemic species on short temporal scales. Factors pertaining to the mode and tempo of archipelago formation and its geographical isolation strongly govern evolutionary pathways available for species diversification, and the potential for successful diversification of dispersed lineages, therefore, appears highly dependent on the timing of arrival, as habitat and resource properties change dramatically over the course of oceanic island evolution. PMID:22900068

Strijk, Joeri S.; Noyes, Richard D.; Strasberg, Dominique; Cruaud, Corinne; Gavory, Fredéric; Chase, Mark W.; Abbott, Richard J.; Thébaud, Christophe

2012-01-01

336

Reprogramming alkaloid biosynthesis in Catharanthus roseus : synthetic biology in plants  

E-print Network

The medicinal plant Madagascar periwinkle (Catharanthus roseus) produces over 130 monoterpene indole alkaloid (MIA) natural products. Many of these compounds have pharmaceutical value, such as the anticancer agents vinblastine ...

Runguphan, Weerawat

2011-01-01

337

Identification of Upland Invasive Jeff Hutchinson  

E-print Network

·Pinelands ·Floodplain forest ·Marshes ·Ruderal Common along corridors and in disturbed sites #12;Herbaceous Plants #12;Madagascar periwinkle (Catharanthus roseus) Habitat: ·Ruderal ·Sandhills ·Scrub ·Terrestrial or epiphytic ·Underground tubers common ·Fronds once- pinnate ·Rachis w/ bi-colored scales

Watson, Craig A.

338

Sex determination in Madagascar geckos of the genus Paroedura (Squamata: Gekkonidae): are differentiated sex chromosomes indeed so evolutionary stable?  

PubMed

Among amniote vertebrates, geckos represent a clade with exceptional variability in sex determination; however, only a minority of species of this highly diverse group has been studied in this respect. Here, we describe for the first time a female heterogamety in the genus Paroedura, the group radiated in Madagascar and adjacent islands. We identified homomorphic ZZ/ZW sex chromosomes with a highly heterochromatic W chromosome in Paroedura masobe, Paroedura oviceps, Paroedura karstophila, Paroedura stumpffi, and Paroedura lohatsara. Comparative genomic hybridization (CGH) revealed that female-specific sequences are greatly amplified in the W chromosome of P. lohatsara and that P. gracilis seems to possess a derived system of multiple sex chromosomes. Contrastingly, neither CGH nor heterochromatin visualization revealed differentiated sex chromosomes in the members of the Paroedura picta-Paroedura bastardi-Paroedura ibityensis clade, which is phylogenetically nested within lineages with a heterochromatic W chromosome. As a sex ratio consistent with genotypic sex determination has been reported in P. picta, it appears that the members of the P. picta-P. bastardi-P. ibityensis clade possess homomorphic, poorly differentiated sex chromosomes and may represent a rare example of evolutionary loss of highly differentiated sex chromosomes. Fluorescent in situ hybridization (FISH) with a telomeric probe revealed a telomere-typical pattern in all species and an accumulation of telomeric sequences in the centromeric region of autosomes in P. stumpffi and P. bastardi. Our study adds important information for the greater understanding of the variability and evolution of sex determination in geckos and demonstrates how the geckos of the genus Paroedura provide an interesting model for studying the evolution of the sex chromosomes. PMID:25056523

Koubová, Martina; Johnson Pokorná, Martina; Rovatsos, Michail; Farka?ová, Klára; Altmanová, Marie; Kratochvíl, Lukáš

2014-12-01

339

Noretta Koertge Department of History and Philosophy of Science  

E-print Network

of multiculturalism. I will defer any critical comments until the end of this paper. One common plea for biodiversity that common medicines such as digitalis and ephedrine come from familiar plants. It goes on to describes new, such as the Madagascar rosy periwinkle, and then concludes: Plants like the periwinkle have contributed

Koertge, Noretta

340

Cover sequences at the northern margin of the Antongil Craton, NE Madagascar  

USGS Publications Warehouse

The island of Madagascar is a collage of Precambrian, generally high-grade metamorphic basement domains, that are locally overlain by unmetamorphosed sedimentary rocks and poorly understood low-grade metasediments. In the Antalaha area of NE Madagascar, two distinct cover sequences rest on high-grade metamorphic and igneous basement rocks of the Archaean Antongil craton and the Neoproterozoic Bemarivo belt. The older of these two cover sequences, the Andrarona Group, consists of low-grade metasedimentary rocks. The younger sequence, the newly defined Ampohafana Formation, consists of unmetamorphosed sedimentary rocks. The Andrarona Group rests on Neoarchaean granites and monzogranites of the Antongil craton and consists of a basal metagreywacke, thick quartzites and an upper sequence of sericite-chlorite meta-mudstones, meta-sandstones and a volcaniclastic meta-sandstone. The depositional age of the volcaniclastic meta-sandstone is constrained in age by U–Pb laser-ablation ICP-MS analyses of euhedral zircons to 1875 ± 8 Ma (2?). Detrital zircons of Archaean and Palaeoproterozoic age represent an input from the Antongil craton and a newly defined Palaeoproterozoic igneous unit, the Masindray tonalite, which underlies the Andrarona Group, and yielded a U–Pb zircon age of 2355 ± 11 Ma (2?), thus constraining the maximum age of deposition of the basal part of the Andrarona Group. The Andrarona Group shows a low-grade metamorphic overprint in the area near Antalaha; illite crystallinity values scatter around 0.17°?2? CuK?, which is within the epizone. The Ampohafana Formation consists of undeformed, polymict conglomerate, cross-bedded sandstone, and red mudstone. An illite crystallinity value of >0.25°?2? CuK? obtained from the rocks is typical of the diagenetic zone. Occurrences of rhyodacite pebbles in the Ampohafana Formation and the intrusion of a basaltic dyke suggest a deposition in a WSW-ENE-trending graben system during the opening of the Indian Ocean in the Upper Cretaceous, that was characterized by extensive rhyolitic to basaltic magmatism along Madagascar's eastern coast.

Bauer, W.; Walsh, G.J.; De Waele, B.; Thomas, Ronald J.; Horstwood, M.S.A.; Bracciali, L.; Schofield, D.I.; Wollenberg, U.; Lidke, D.J.; Rasaona, I.T.; Rabarimanana, M.H.

2011-01-01

341

A Preliminary Microsatellite Linkage Map of the Red Drum (Sciaenops ocellatus)  

E-print Network

?-tailed with an arbitrary primer sequence, in this case taken from the microsatellite primer sequence CATR8 used in the PCR amplification of genomic DNA from the Madagascar periwinkle, Catharanthus roseus (Shokeen et al. 2007). In addition to the tail.... KUMAR and S. BHATIA, 2007 Isolation and characterization of microsatellite markers for analysis of molecular variation in the medicinal plant Madagascar periwinkle (Catharanthus roseus (L.) G. Don). Plant Science 172: 441-451. SINGER, A., H...

Hollenbeck, Christopher

2011-01-11

342

Malagasyprinus, a new genus of the Saprininae from Madagascar with description of two new species (Coleoptera, Histeridae, Saprininae) (First contribution to the knowledge of the Histeridae of Madagascar)  

PubMed Central

Abstract Based on the results of recent phylogenetic analysis of the higher taxa of the Saprininae as well as external morphological characters, especially the presence of deep and large prosternal foveae, and the shape and position of the sensory organs of the antennal club, the species Saprinus (s.str.) caeruleatus Lewis, 1905 is excluded from the genus Saprinus and a new genus Malagasyprinus, exclusive to Madagascar, is established for it. The new genus shows mainly characters that are apomorphic for the subfamily and contains another two, highly similar allopatric species Malagasyprinus perrieri sp. n., and Malagasyprinus diana sp. n., described herein. The three species are best separated from each other by the structure of the prosternum and male terminalia, especially the shape of the aedeagus. We re-describe Malagasyprinus caeruleatus comb. n. and provide Malagasyprinus perrieri and Malagasyprinus diana with brief differential diagnoses. All taxon descriptions are accompanied with color habitat photographs, SEM micrographs and drawings of their male genitalia. A key to the species of Malagasyprinus is given. Sensory structures of the antenna of Malagasyprinus caeruleatus comb. n. are likewise depicted herein. The systematic position of the newly erected genus is discussed. A lectotype of Saprinus caeruleatus Lewis, 1905 is designated. PMID:24146560

Lackner, Tomáš; Gomy, Yves

2013-01-01

343

Anjozorobe Hantavirus, a New Genetic Variant of Thailand Virus Detected in Rodents from Madagascar  

PubMed Central

Abstract Until now, there was only serological evidence that hantaviruses were circulating in rodents and infecting humans from Madagascar. To assess the presence of a hantavirus on the island, between October, 2008, and March, 2010, we sampled 585 rodents belonging to seven species in the Anjozorobe-Angavo forest corridor, 70?km north from the capital city Antananarivo. A hantavirus was detected from organs of the ubiquist roof rat (Rattus rattus) and of the endemic Major's tufted-tailed rat (Eliurus majori). Amazingly, sequence analysis of the S (small), M (medium), and L (large) coding DNA sequence of this virus showed that the Anjozorobe strain (proposed name) was a new genetic variant of Thailand virus (THAIV) that comprises other variants found in Southeast Asia. Because THAIV is suspected of causing hemorrhagic fever with renal syndrome in humans, ongoing studies are addressing the risk of infection by this new variant in the Malagasy population. PMID:24575755

Razafindralambo, Nadia Kaloina; Lacoste, Vincent; Olive, Marie-Marie; Barivelo, Tony Andrianaivo; Soarimalala, Voahangy; Heraud, Jean-Michel; Lavergne, Anne

2014-01-01

344

Beautiful bright belly: A distinctive new microhylid frog (Amphibia: Stumpffia) from eastern Madagascar.  

PubMed

We describe a new red-bellied species of the microhylid frog genus Stumpffia from the Andasibe region (18°56' S, 48°25' E, ca. 900 m elevation) in central-eastern Madagascar. Stumpffia kibomena sp. nov. differs from all other described Stumpffia species in coloration, morphology, and by genetic differentiation in the mitochondrial 16S  rRNA gene (?8.6% uncorrected p-distance to all other nominal species of the genus). It is furthermore distinguished from most other Stumpffia species by its advertisement calls. The new species is reliably known only from a few specimens collected in the Andasibe region and based on the limited knowledge we suggest its IUCN Red List classification as "Data Deficient". PMID:25781734

Glaw, Frank; Vallan, Denis; Andreone, Franco; Edmonds, Devin; Dolch, Rainer; Vences, Miguel

2015-01-01

345

Chemical composition of the essential oil from Croton kimosorum, an endemic species to Madagascar.  

PubMed

Croton kimosorum Leandri is an endemic species to Madagascar. The chemical composition of aerial parts, leaf and stem oils is reported for the first time. Analysis was carried out by combination of chromatographic (CC, GC), spectroscopic and spectrometric (MS, 13C NMR) techniques. In total, 76 compounds have been identified. Essential oil isolated from aerial parts contained mainly linalool (21.6%), sabinene (10.4%), 1,8-cineole (6.3%), beta-pinene (6.2%), (E)-beta-caryophyllene (5.9%), terpinen-4-ol (4.8%), geraniol (4,5%) and germacrene D (2.3%). In comparison with the first sample, the composition of leaf and stem oils varied slightly, while essential oil isolated by vapor distillation from a semi-industrial still exhibited similar composition. PMID:24660481

Rabehaja, Delphin J R; Ihandriharison, Harilala; Ramanoelina, Panja A R; Benja, Rakotonirina; Ratsimamanga-Urverg, Suzanne; Bighelli, Ange; Casanova, Joseph; Tomi, Félix

2014-01-01

346

Habituation of hissing by Madagascar hissing cockroaches (Gromphadorhina portentosa): evidence of discrimination between humans?  

PubMed

Anecdotal reports suggest that insects can be "tamed" with frequent human contact. In the present experiment, repeated handling of Madagascar hissing cockroaches by the same person resulted in habituation of the hissing response in ten of 12 subjects. These subjects were then handled by a novel person in order to determine whether habituation might be specific to a particular human. Four of ten "habituated" subjects immediately began to hiss in the presence of the novel handler, but again ceased hissing when contact with the familiar person was reestablished. Our results suggest that in some cases "taming" may be person-specific, rather than a generalized response to humans. These preliminary findings are the first evidence of discrimination between humans by an insect species, although comparable results are well documented in mammals and birds. PMID:15519003

Davis, Hank; Heslop, Emily

2004-11-30

347

A new Ixodes species (Acari: Ixodidae), parasite of shrew tenrecs (Afrosoricida: Tenrecidae) in Madagascar.  

PubMed

Abstract :? A new tick species belonging to the African subgenus Afrixodes Morel, 1966 of the genus Ixodes Latreille, 1795, namely, Ixodes (Afrixodes) microgalei n. sp., is described. Females of this species are most similar to those of Ixodes colasbelcouri Arthur, 1957 and Ixodes nesomys Uilenberg & Hoogstraal, 1969. The female of the new species can easily be differentiated from I. colasbelcouri by a short spur on coxae IV, and from I. nesomys by longer spurs on coxae I and large punctations on its scutum. Ixodes microgalei is known only from the eastern humid forest of Madagascar, specifically in the Province of Antananarivo, where its females have been collected from several species of shrew tenrecs (Afrosoricida, Tenrecidae), namely, Microgale dobsoni Thomas, Microgale parvula Grandidier, and Microgale soricoides Jenkins. PMID:23901784

Apanaskevich, Dmitry A; Soarimalala, Voahangy; Goodman, Steven M

2013-12-01

348

A genome sequence resource for the aye-aye (Daubentonia madagascariensis), a nocturnal lemur from Madagascar.  

PubMed

We present a high-coverage draft genome assembly of the aye-aye (Daubentonia madagascariensis), a highly unusual nocturnal primate from Madagascar. Our assembly totals ~3.0 billion bp (3.0 Gb), roughly the size of the human genome, comprised of ~2.6 million scaffolds (N50 scaffold size = 13,597 bp) based on short paired-end sequencing reads. We compared the aye-aye genome sequence data with four other published primate genomes (human, chimpanzee, orangutan, and rhesus macaque) as well as with the mouse and dog genomes as nonprimate outgroups. Unexpectedly, we observed strong evidence for a relatively slow substitution rate in the aye-aye lineage compared with these and other primates. In fact, the aye-aye branch length is estimated to be ~10% shorter than that of the human lineage, which is known for its low substitution rate. This finding may be explained, in part, by the protracted aye-aye life-history pattern, including late weaning and age of first reproduction relative to other lemurs. Additionally, the availability of this draft lemur genome sequence allowed us to polarize nucleotide and protein sequence changes to the ancestral primate lineage-a critical period in primate evolution, for which the relevant fossil record is sparse. Finally, we identified 293,800 high-confidence single nucleotide polymorphisms in the donor individual for our aye-aye genome sequence, a captive-born individual from two wild-born parents. The resulting heterozygosity estimate of 0.051% is the lowest of any primate studied to date, which is understandable considering the aye-aye's extensive home-range size and relatively low population densities. Yet this level of genetic diversity also suggests that conservation efforts benefiting this unusual species should be prioritized, especially in the face of the accelerating degradation and fragmentation of Madagascar's forests. PMID:22155688

Perry, George H; Reeves, Darryl; Melsted, Páll; Ratan, Aakrosh; Miller, Webb; Michelini, Katelyn; Louis, Edward E; Pritchard, Jonathan K; Mason, Christopher E; Gilad, Yoav

2012-01-01

349

Introducing auto-disable syringes to the national immunization programme in Madagascar.  

PubMed Central

OBJECTIVE: To evaluate the safety and coverage benefits of auto-disable (AD) syringes, weighed against the financial and logis- tical costs, and to create appropriate health policies in Madagascar. METHODS: Fifteen clinics in Madagascar, trained to use AD syringes, were randomized to implement an AD syringe only, mixed (AD syringes used only on non-routine immunization days), or sterilizable syringe only (control) programme. During a five-week period, data on administered vaccinations were collected, interviews were conducted, and observations were recorded. FINDINGS: The use of AD syringes improved coverage rates by significantly increasing the percentage of vaccines administered on non-routine immunization days (AD-only 4.3%, mixed 5.7%, control 1.1% (P<0.05)). AD-only clinics eliminated sterilization sessions for vaccinations, whereas mixed clinics reduced the number of sterilization sessions by 64%. AD syringes were five times more expensive than sterilizable syringes, which increased AD-only and mixed clinics' projected annual injection costs by 365% and 22%, respectively. However, introducing AD syringes for all vaccinations would only increase the national immunization budget by 2%. CONCLUSION: The use of AD syringes improved vaccination coverage rates by providing ready-to-use sterile syringes on non-routine immunization days and decreasing the number of sterilization sessions, thereby improving injection safety. The mixed programme was the most beneficial approach to phasing in AD syringes and diminishing logistical complications, and it had minimal costs. AD syringes, although more expensive, can feasibly be introduced into a developing country's immunization programme to improve vaccination safety and coverage. PMID:14576886

Drain, Paul K.; Ralaivao, Josoa S.; Rakotonandrasana, Alexander; Carnell, Mary A.

2003-01-01

350

Randomised controlled trial of alternative male and female condom promotion strategies targeting sex workers in Madagascar  

PubMed Central

Objectives To assess whether individual clinic?based counselling as a supplement to peer education for male and female condom promotion leads to greater use of protection and lower STI prevalence among sex workers in Madagascar already exposed to intensive male condom promotion. Methods In two public dispensaries in Madagascar, a total of 901 sex workers were randomly allocated between two alternative male and female condom promotion interventions: peer education only, or peer education supplemented with individual clinic?based counselling. Participants were followed for 12?months. Every 2?months they made clinic visits, where they were interviewed on condom use. Peer educators counselled all participants on condom use as they accompanied their assigned participants to study visits. Participants assigned to receive the supplemental intervention were counselled by a trained clinician following study interviews. Participants were tested and treated for chlamydia, gonorrhoea and trichomoniasis every 6?months. We used logistic regression to assess whether the more intensive intervention was associated with reduced STI prevalence. Use of protection with clients and non?paying partners was assessed by study arm, site, and visit. Results There was no statistically significant association between study arm and aggregated STI prevalence. No substantial differences in levels of reported protection were noted between study groups. Conclusions This study found little evidence for gains from more thorough clinical counselling on male and female condom use. These findings suggest that less clinically intensive interventions such as peer education could be suitable for male and female condom promotion in populations already exposed to barrier method promotion. PMID:17591662

Hoke, Theresa H; Feldblum, Paul J; Van Damme, Kathleen; Nasution, Marlina D; Grey, Thomas W; Wong, Emelita L; Ralimamonjy, Louisette; Raharimalala, Leonardine; Rasamindrakotroka, Andry

2007-01-01

351

Immune Responses to Plague Infection in Wild Rattus rattus, in Madagascar: A Role in Foci Persistence?  

PubMed Central

Background Plague is endemic within the central highlands of Madagascar, where its main reservoir is the black rat, Rattus rattus. Typically this species is considered susceptible to plague, rapidly dying after infection inducing the spread of infected fleas and, therefore, dissemination of the disease to humans. However, persistence of transmission foci in the same area from year to year, supposes mechanisms of maintenance among which rat immune responses could play a major role. Immunity against plague and subsequent rat survival could play an important role in the stabilization of the foci. In this study, we aimed to investigate serological responses to plague in wild black rats from endemic areas of Madagascar. In addition, we evaluate the use of a recently developed rapid serological diagnostic test to investigate the immune response of potential reservoir hosts in plague foci. Methodology/Principal Findings We experimentally infected wild rats with Yersinia pestis to investigate short and long-term antibody responses. Anti-F1 IgM and IgG were detected to evaluate this antibody response. High levels of anti-F1 IgM and IgG were found in rats one and three weeks respectively after challenge, with responses greatly differing between villages. Plateau in anti-F1 IgM and IgG responses were reached for as few as 500 and 1500 colony forming units (cfu) inoculated respectively. More than 10% of rats were able to maintain anti-F1 responses for more than one year. This anti-F1 response was conveniently followed using dipsticks. Conclusion/Significance Inoculation of very few bacteria is sufficient to induce high immune response in wild rats, allowing their survival after infection. A great heterogeneity of rat immune responses was found within and between villages which could heavily impact on plague epidemiology. In addition, results indicate that, in the field, anti-F1 dipsticks are efficient to investigate plague outbreaks several months after transmission. PMID:22719908

Andrianaivoarimanana, Voahangy; Telfer, Sandra; Rajerison, Minoarisoa; Ranjalahy, Michel A.; Andriamiarimanana, Fehivola; Rahaingosoamamitiana, Corinne; Rahalison, Lila; Jambou, Ronan

2012-01-01

352

[Evaluation of the management of tuberculosis in children in Madagascar. Results of a multicentric study].  

PubMed

In Madagascar, tuberculosis remains an important cause of morbidity and letality with a Risk of Annual Tubercular Infection about 1% in 1996 in spite of a vaccination rate of 82.6% and tubercular drugs free of charge. In 1995, the National Tubercular Control Program detected 7,000 cases of pulmonary tuberculosis and expected more than 12,000 cases per year. This study was carried out in order to review the management and the treatment of the child tuberculosis in Madagascar. This retrospective study was conducted in four pediatric units of the General hospital of Befelatanana (A and B), Ambohimiandra Hospital and Regional Hospital Centre of Toliara for a twenty four months period from January 1997 to December 1998. All the less than 15-year-old children medical files were consulted. 214 cases were suspected of tuberculosis. 133 of them were treated upon clinical presumption basis and/or radiological exams (33 bacteriological and/or histopathological exams were only realized). 56% of the cases were vaccinated by BCG vaccine. Respiratory diseases with fever motive 46% of hospitalization. The majority of these children are living in poor conditions and 38% of them had malnutrition. Were found as clinical manifestations: 47% of pulmonary tuberculosis (among them 20% were smear-positive pulmonary tuberculosis), 12% had ganglionar tuberculosis, 10% peritoneal tuberculosis, 8% a tubercular meningitis, 5% a Pott-disease and 2% a miliary-disease. Mortality increases with suffocation. 18% of cases died, especially infants and in tubercular meningitis. The authors conclude that management and treatment of tuberculosis need an early diagnosis. But the diagnosis is difficult in front of non specific clinical manifestations in children and due to lack of means and national agreement which settle up diagnosis and therapy. A scoring system based upon clinical signs in agreement with complementary medical tests is desirable. PMID:12478966

Rasamoelisoa, J M; Tovone, X G; Razoeliarinoro, H V; Rakotoarimanana, D R

1999-01-01

353

The Burden of Acute Disease in Mahajanga, Madagascar – A 21 Month Study  

PubMed Central

Background Efforts to develop effective and regionally-appropriate emergency care systems in sub-Saharan Africa are hindered by a lack of data on both the burden of disease in the region and on the state of existing care delivery mechanisms. This study describes the burden of acute disease presenting to an emergency unit in Mahajanga, Madagascar. Methods and Findings Handwritten patient registries on all emergency department patients presenting between 1 January 2011 and 30 September 2012 were reviewed and data entered into a database. Data included age, sex, diagnosis, and disposition. We classified diagnoses into Clinical Classifications Software (CCS) multi-level categories. The population was 53.5% male, with a median age of 31 years. The five most common presenting conditions were 1) Superficial injury; contusion, 2) Open wounds of head; neck; and trunk, 3) Open wounds of extremities, 4) Intracranial injury, and 5) Unspecified injury and poisoning. Trauma accounted for 48%, Infectious Disease for 15%, Mental Health 6.1%, Noncommunicable 29%, and Neoplasms 1.2%. The acuity seen was high, with an admission rate of 43%. Trauma was the most common reason for admission, representing 19% of admitted patients. Conclusions This study describes the burden of acute disease at a large referral center in northern Madagascar. The Centre Hôpitalier Universitaire de Mahajanga sees a high volume of acutely ill and injured patients. Similar to other reports from the region, trauma is the most common pathology observed, though infectious disease was responsible for the majority of adult mortality. Typhoid fever other intestinal infections were the most lethal CCS-coded pathologies. By utilizing a widely understood classification system, we are able to highlight contrasts between Mahajanga’s acute and overall disease burden as well as make comparisons between this region and the rest of the globe. We hope this study will serve to guide the development of context-appropriate emergency medicine systems in the region. PMID:25738300

Kannan, Vijay C.; Andriamalala, Clara N.; Reynolds, Teri A.

2015-01-01

354

Geochronology and 4+ thermometry of ultrahigh-temperature (UHT) metamorphism in southern Madagascar  

NASA Astrophysics Data System (ADS)

Ultrahigh temperature (UHT) metamorphism--regional metamorphism at >900° C--in a collisional setting requires some combination of: i) unusually radiogenic crust, ii) advection of heat by magmatism, iii) conduction of mantle-derived heat, and iv) shear heating. The Neoproterozoic continental collision zone exposed in Madagascar provides a good opportunity to investigate these potential causes; we use three 4+ thermometers (Zr-in-rutile, Ti-in-zircon, and Ti-in-quartz) and U/Th-Pb geochronology of monazite and zircon to evaluate the magnitude, timing, and duration of UHT metamorphism in southern Madagascar. U-Pb dates from metamorphic monazite and zircon with complex intragrain (re)crystallization textures range from ~600 Ma to ~500 Ma. Zircon and monazite with HREE depletion and dates of 600-540 Ma suggest (re)crystallization in the presence of garnet. All monazite shows negative Eu anomalies (compatible with the presence of plagioclase), but monazite with dates from ~570 to ~530 Ma has more pronounced anomalies. Zr-in-rutile temperatures span 700 to 960° C and Ti-in-quartz temperatures span 600 to 950° C. The UHT metamorphism is assumed to postdate both the accretion of an arc terrane to West Gondwana at ~600 Ma and the suturing of East and West Gondwana prior to ~570 Ma. The 40 Myr between distinct episodes of alkali plutonism at ~570 Ma (deformed) and ~530 Ma (nondeformed) coincide with more-negative Eu anomalies in monazite, and may reflect the period of orogenesis associated with UHT metamorphism. The measured K, Th, and U contents of rocks within the UHT domain [GAF-BGR, 2008] indicate an average heat production of >5 ?W/m3. This is sufficient to produce UHT metamorphism in 60-km thick crust within 40 Myr.

Horton, F.; Hacker, B. R.; Kylander-Clark, A. R.

2013-12-01

355

Madagascar Highland erosion: What can we learn from the archive precipitation data?  

NASA Astrophysics Data System (ADS)

In Madagascar, soil erosion is significant even when it is compared to world averages, resulting in special geomorphic forms known as lavakas appearing in the Highland regions of the island. The development of these features is due to rather unique multifactorial environmental conditions. Among many factors (geology, soil composition, human influence, etc.) the spatial and temporal distribution of precipitation is a key factor. The presence of the dry and wet season seems to be responsible for the enhanced generation of small cracks that might eventually lead to the development of a gully. However, the way of the development of such gully erosions are unknown. To what extent of the actual precipitation pattern to what extent the weather contributes to the aforementioned phenomenon has not yet been studied in great detail. The aim of our research is to study the climatic and weather conditions of lavaka-prone areas for the last decades. The typical cyclonal pattern affects the Madagascar Highlands in various ways. The precipitation and the soil moisture data show that the spatial distribution can be correlated with the appearance of lavakas to a given extent, however the local distribution cannot be explained only based on the precipitation pattern. The severity of the wet season varies strongly in the various decades leading to different precipitation maxima in January-March period. In general the effectiveness of the gully erosion is thought to be highly enhanced if the run-off of the area show large temporal variations. According to our studies this variability is quite high in certain seasons, and, despite of the low spatial resolution, related to the lavaka-prone areas. However, neither the amount of the precipitation, nor the variability alone cannot explain the high variation found in the spatial density and length distribution. Further multidisciplinary studies are necessary to draw conclusions about lavaka formation and describe the process of lavaka development. This is ILARG-contribution Nr. 11.

Imola Szabó, Amanda; Raveloson, Andrea; Székely, Balázs

2014-05-01

356

Early-warning health and process indicators for sentinel surveillance in Madagascar 2007-2011  

PubMed Central

Background: Epidemics pose major threats in resource-poor countries, and surveillance tools for their early detection and response are often inadequate. In 2007, a sentinel surveillance system was established in Madagascar, with the aim of rapidly identifying potential epidemics of febrile or diarrhoeal syndromes and issuing alerts. We present the health and process indicators for the five years during which this system was constructed, showing the spatiotemporal trends, early-warning sign detection capability and process evaluation through timely analyses of high-quality data. Methods: The Malagasy sentinel surveillance network is currently based on data for fever and diarrhoeal syndromes collected from 34 primary health centres and reported daily via the transmission of short messages from mobile telephones. Data are analysed daily at the Institut Pasteur de Madagascar to make it possible to issue alerts more rapidly, and integrated process indicators (timeliness, data quality) are used to monitor the system. Results: From 2007 to 2011, 917,798 visits were reported. Febrile syndromes accounted for about 11% of visits annually, but the trends observed differed between years and sentinel sites. From 2007 to 2011, 21 epidemic alerts were confirmed. However, delays in data transmission were observed (88% transmitted within 24 hours in 2008; 67% in 2011) and the percentage of forms transmitted each week for validity control decreased from 99.9% in 2007 to 63.5% in 2011. Conclusion: A sentinel surveillance scheme should take into account both epidemiological and process indicators. It must also be governed by the main purpose of the surveillance and by local factors, such as the motivation of healthcare workers and telecommunication infrastructure. Permanent evaluation indicators are required for regular improvement of the system. PMID:25598869

Rajatonirina, Soatiana; Rakotomanana, Fanjasoa; Randrianasolo, Laurence; Razanajatovo, Norosoa Harline; Andriamandimby, Soa Fy; Ravolomanana, Lisette; Randrianarivo-Solofoniaina, Armand Eugène; Reynes, Jean-Marc; Piola, Patrice; Finlay-Vickers, Alyssa; Heraud, Jean-Michel; Richard, Vincent

2014-01-01

357

Forest Management Devolution: Gap Between Technicians' Design and Villagers' Practices in Madagascar  

NASA Astrophysics Data System (ADS)

In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems.

Rives, Fanny; Carrière, Stéphanie M.; Montagne, Pierre; Aubert, Sigrid; Sibelet, Nicole

2013-10-01

358

Petrogenesis of high-K metagranites in the Kerala Khondalite Belt, southern India: a possible magmatic-arc link between India, Sri Lanka, and Madagascar  

NASA Astrophysics Data System (ADS)

The Proterozoic Kerala Khondalite Belt (KKB), southern India preserves a distinct high-grade terrain that is interpreted to have been situated adjacent to Madagascar and Sri Lanka during Gondwana assembly. As such, it has become a major focus for testing models of supercontinent amalgamation and dispersal. The lithounits of KKB have remarkable petrological similarities to the Highland Complex (HC) of Sri Lanka and south-central Madagascar. However, there is no well-constrained petrogenetic model for the KKB that fits explicitly within a supercontinent reconstruction model. We present here results from our on-going studies on the origin and evolution of K-rich (potassic, where K2O/Na2O > 1) gneisses of KKB in relation to Proterozoic supercontinent events. Our results show, in a major departure from earlier metasedimentary origin, that potassic gneisses are metamorphosed granitoids. The metagranitoid samples display high K2O contents and low Al2O3/(FeO + MgO + TiO2) values. They are moderate to strongly peraluminous (ASI values ranging from 1.05 to 1.47) rocks showing mineralogical, petrological, and geochemical characteristics distinctive of the high-K calc-alkaline suites. Typical of igneous suites, the high-K metagranites show minor variation in chemical compositions with most oxides showing negative correlation with SiO2. Geochemistry illustrates distinctive features of arc-related magmas with LILE (K, Rb, and Th) and LREE enriched patterns and considerable depletion of HSFE (Nb, Zr, and Ti). The high-K metagranites are further characterized by strong negative anomalies of Eu (Eu/Eu* = 0.10-0.44) and Sr, suggesting melting in plagioclase stability field and retention of plagioclase in the residual phase. Petrogenetic discrimination for granitoids, using major and trace elements demonstrates that the high-K metagranites of the KKB formed by partial melting of igneous source in lower- to middle-crust levels. Overall the geochemical features are supportive of origin in relation to a convergent margin setting, possibly in a continental magmatic arc system, which can be connected to the amalgamation and dispersal of continental fragments in a supercontinent event. This study, therefore, provides a lead towards more robust comparisons between the Proterozoic supercontinent events and processes.

Sreejith, C.; Ravindra Kumar, G. R.

2013-01-01

359

Tracing Arab-Islamic Inheritance in Madagascar: Study of the Y-chromosome and Mitochondrial DNA in the Antemoro  

PubMed Central

Madagascar is located at the crossroads of the Asian and African worlds and is therefore of particular interest for studies on human population migration. Within the large human diversity of the Great Island, we focused our study on a particular ethnic group, the Antemoro. Their culture presents an important Arab-Islamic influence, but the question of an Arab biological inheritance remains unresolved. We analyzed paternal (n=129) and maternal (n=135) lineages of this ethnic group. Although the majority of Antemoro genetic ancestry comes from sub-Saharan African and Southeast Asian gene pools, we observed in their paternal lineages two specific haplogroups (J1 and T1) linked to Middle Eastern origins. This inheritance was restricted to some Antemoro sub-groups. Statistical analyses tended to confirm significant Middle Eastern genetic contribution. This study gives a new perspective to the large human genetic diversity in Madagascar. PMID:24278350

Capredon, Mélanie; Brucato, Nicolas; Tonasso, Laure; Choesmel-Cadamuro, Valérie; Ricaut, François-Xavier; Razafindrazaka, Harilanto; Rakotondrabe, Andriamihaja Bakomalala; Ratolojanahary, Mamisoa Adelta; Randriamarolaza, Louis-Paul; Champion, Bernard; Dugoujon, Jean-Michel

2013-01-01

360

Tracing Arab-Islamic inheritance in Madagascar: study of the Y-chromosome and mitochondrial DNA in the Antemoro.  

PubMed

Madagascar is located at the crossroads of the Asian and African worlds and is therefore of particular interest for studies on human population migration. Within the large human diversity of the Great Island, we focused our study on a particular ethnic group, the Antemoro. Their culture presents an important Arab-Islamic influence, but the question of an Arab biological inheritance remains unresolved. We analyzed paternal (n=129) and maternal (n=135) lineages of this ethnic group. Although the majority of Antemoro genetic ancestry comes from sub-Saharan African and Southeast Asian gene pools, we observed in their paternal lineages two specific haplogroups (J1 and T1) linked to Middle Eastern origins. This inheritance was restricted to some Antemoro sub-groups. Statistical analyses tended to confirm significant Middle Eastern genetic contribution. This study gives a new perspective to the large human genetic diversity in Madagascar. PMID:24278350

Capredon, Mélanie; Brucato, Nicolas; Tonasso, Laure; Choesmel-Cadamuro, Valérie; Ricaut, François-Xavier; Razafindrazaka, Harilanto; Rakotondrabe, Andriamihaja Bakomalala; Ratolojanahary, Mamisoa Adelta; Randriamarolaza, Louis-Paul; Champion, Bernard; Dugoujon, Jean-Michel

2013-01-01

361

Planthopper (Hemiptera: Flatidae) parasitized by larval erythraeid mite (Trombidiformes: Erythraeidae)-a description of two new species from western Madagascar.  

PubMed

Descriptions of Dambullaeus adonis M?kol et Moniuszko SP NOV: (Trombidiformes: Erythraeidae, Callidosomatinae) and Latois nigrolineata ?wierczewski et Stroi?ski SP NOV: (Hemiptera: Fulgoromorpha, Flatidae) from Madagascar are provided. The first host record for ectoparasitic larvae of Dambullaeus Haitlinger, 2001 and the first evidence on host-parasite association between flatid adult and erythraeid larvae are given. Genus Dambullaeus, known exclusively from larvae and now comprising two species of Gondwanan distribution, is critically reappraised. PMID:25434029

M?kol, Joanna; Moniuszko, Hanna; Swierczewski, Dariusz; Stroi?ski, Adam

2014-01-01

362

Petrogenesis of a basanite–tephrite–phonolite volcanic suite in the Bobaomby (Cap d’Ambre) peninsula, northern Madagascar  

Microsoft Academic Search

The Late Cenozoic Bobaomby volcanic field is located in the northernmost Madagascar, in the area north of the Massif d’Ambre. It comprises widely scattered outcrops of lava flows, dykes, scoria cones, tuff rings and plugs, emplaced in the Meso-Cenozoic sedimentary rocks of the Diego Basin. The Bobaomby rocks range in composition from Mg-rich, sodic basanite to phonolite (MgO from 13

L. Melluso; V. Morra; H. Riziky; J. Veloson; M. Lustrino; L. Del Gatto; V. Modeste

2007-01-01

363

Metabolism and temperature regulation during daily torpor in the smallest primate, the pygmy mouse lemur ( Microcebus myoxinus ) in Madagascar  

Microsoft Academic Search

Thermoregulation, energetics and patterns of torpor in the pygmy mouse lemur, Microcebus myoxinus, were investigated under natural conditions of photoperiod and temperature in the Kirindy\\/CFPF Forest in western Madagascar.\\u000a M. myoxinus entered torpor spontaneously during the cool dry season. Torpor only occurred on a daily basis and torpor bout duration was\\u000a on average 9.6?h, and ranged from 4.6?h to 19.2?h.

J. Schmid; T. Ruf; G. Heldmaier

2000-01-01

364

The madagascar hissing-cockroach mite (Gromphadorholaelaps schaeferi): First observation of its larva and ptyalophagy in Acari  

Microsoft Academic Search

Postembryonic development in the Madagascar hissing-cockroach mite, Gromphadorholaelaps schaeferi, features a mobile, but non-feeding larva of very short duration (4-8 hours). Until now, this mite was thought to be protonymphiparous, which is not consistent with other members of this taxon. In this study, four distinct stages were found: larva, protonymph, deutonymph, and adult. The larva exists for mobility and escape

J. A. Yoder

1996-01-01

365

Stable carbon isotope values document how a Late Holocene expansion in grasslands impacted vertebrates in northwestern Madagascar  

NASA Astrophysics Data System (ADS)

Madagascar is home to some of the world's most distinctive plants and animals. Unfortunately, forest loss and habitat degradation has had a dramatic impact on both floral and faunal communities. Here we use carbon isotope values in radiocarbon-dated bones to examine how the vertebrate community at Anjohibe Cave, northwestern Madagascar, responded to a Late Holocene increase in C4 grass abundance. Our data demonstrate that major changes in the vegetation and animal community are recent phenomena at Anjohibe. Extinct lemurs and hippopotamuses were present until ca. 1500 years ago. These taxa relied exclusively on C3 resources. Locally extirpated fauna were present until 300 years ago. The majority of these species also relied on C3 resources. Their presence strongly suggests that the region surrounding the cave was more wooded than it is now, possibly as recently as 300 years ago. All introduced individuals are modern. Rats (Rattus sp.), shrews (Suncus murinus), and the giant frog Hoplobatrachus cf. tigrinus, have remarkably high carbon isotope values, implicating substantial ingestion of C4 foods. It is possible that grass abundance has increased dramatically in the past 100 years. Alternatively, opportunistically granivorous rats and shrews may selectively consume seeds from C4 grasses. In agreement with previous studies, stable isotope data reveal details of vegetation and faunal turnover in Northwestern Madagascar. Grasses have increased, forest dwelling species have vanished, and introduced taxa are exploiting a novel niche.

Crowley, B. E.; Samonds, K.

2012-12-01

366

Assessing flavivirus, lentivirus, and herpesvirus exposure in free-ranging ring-tailed lemurs in southwestern Madagascar.  

PubMed

The ring-tailed lemur (Lemur catta) is an endangered species found in southwestern Madagascar, and understanding infectious disease susceptibility is an essential step towards the preservation of wild and captive lemur populations. Lemurs are primates that are widely dispersed throughout the island of Madagascar and may serve as hosts or reservoirs for zoonotic infections. The aim of this study was to determine the prevalence of antibodies to West Nile virus (WNV), simian immunodeficiency virus (SIV), and herpes simplex virus type 1 (HSV-1) in a population of free-ranging ring-tailed lemur from the Beza Mahafaly Special Reserve, Madagascar. Samples were collected from 50 animals during field capture studies in June and July 2004 and assayed for presence of viral antibodies during the 12 mo following collection. Forty-seven of the 50 lemurs sampled had antibodies against WNV detectable by epitope-blocking enzyme-linked immunosorbent assay (ELISA). In addition, 50 of 50 samples had titers against WNV ranging from 80 to > or = 1,280 using plaque reduction neutralization test (PRNT(90)). Ten lemurs had antibodies against lentiviral antigens as determined by Western blot analysis. None of the lemurs had antibodies against HSV-1 using ELISA. PMID:17347392

Sondgeroth, Kerry; Blitvich, Brad; Blair, Carol; Terwee, Julie; Junge, Randall; Sauther, Michelle; VandeWoude, Sue

2007-01-01

367

Retrospective study of methylmercury and other metal(loid)s in Madagascar unpolished rice (Oryza sativa L.).  

PubMed

The rice ingestion rate in Madagascar is among the highest globally; however studies concerning metal(loid) concentrations in Madagascar rice are lacking. For Madagascar unpolished rice (n = 51 landraces), levels of toxic elements (e.g., total mercury, methylmercury, arsenic and cadmium) as well as essential micronutrients (e.g., zinc and selenium) were uniformly low, indicating potentially both positive and negative health effects. Aside from manganese (Wilcoxon rank sum, p < 0.01), no significant differences in concentrations for all trace elements were observed between rice with red bran (n = 20)and brown bran (n = 31) (Wilcoxon rank sum, p = 0.06-0.91). Compared to all elements in rice,rubidium (i.e., tracer for phloem transport) was most positively correlated with methylmercury (Pearson'sr = 0.33, p < 0.05) and total mercury (r = 0.44, p < 0.05), while strontium (i.e., tracer for xylemtransport) was least correlated with total mercury and methylmercury (r < 0.01 for both), suggesting inorganic mercury and methylmercury were possibly more mobile in phloem compared to xylem. PMID:25463705

Rothenberg, Sarah E; Mgutshini, Nomathamsanqa L; Bizimis, Michael; Johnson-Beebout, Sarah E; Ramanantsoanirina, Alain

2015-01-01

368

Geochemistry of phlogopite, diopside, calcite, anhydrite and apatite pegmatites and syenites of southern Madagascar: evidence for crustal silicocarbonatitic (CSC) melt formation in a Panafrican collisional tectonic setting  

NASA Astrophysics Data System (ADS)

The phlogopite, diopside, calcite, anhydrite and apatite pegmatites of Ampandrandava and Beraketa are examples for the many other pegmatites of similar silicocarbonatitic composition found in the Bekily and Betroka-Beraketa Precambrian belts of southern Madagascar. The two studied pegmatites and associated syenites crystallised from immiscible silicocarbonatitic and peralkaline syenitic melts in a time span between 515 and 504 Ma in the final extensional phase of the Panafrican continental collision and connected metamorphic/metasomatic event. Model T Nd ages suggest that the melts were produced by partial melting of 3.5 Ga partially evaporitic continental crust. The studied pegmatites and genetically associated syenitic rocks are very rare examples for crustal silicocarbonatitic melts generated in a Panafrican collisional setting. The overwhelming majority of carbonatites and associated peralkaline rocks are mantle derived, much poorer in phosphate and sulfate and found in a cratonic environment. In light of the present results, genetic models for other sulfate- and phosphate-rich magmatic rocks (e.g., phlogopite-apatite-calcite mineralisations in the Grenville-Hasting formation in Canada and in the Sludyanka group in Eastern Siberia) should be reevaluated.

Morteani, G.; Kostitsyn, Y. A.; Gilg, H. A.; Preinfalk, C.; Razakamanana, T.

2013-04-01

369

The Madagascar hissing cockroach as a novel surrogate host for Burkholderia pseudomallei, B. mallei and B. thailandensis  

PubMed Central

Background Burkholderia pseudomallei and Burkholderia mallei are gram-negative pathogens responsible for the diseases melioidosis and glanders, respectively. Both species cause disease in humans and animals and have been designated as category B select agents by the Centers for Disease Control and Prevention (CDC). Burkholderia thailandensis is a closely related bacterium that is generally considered avirulent for humans. While it can cause disease in rodents, the B. thailandensis 50% lethal dose (LD50) is typically???104-fold higher than the B. pseudomallei and B. mallei LD50 in mammalian models of infection. Here we describe an alternative to mammalian hosts in the study of virulence and host-pathogen interactions of these Burkholderia species. Results Madagascar hissing cockroaches (MH cockroaches) possess a number of qualities that make them desirable for use as a surrogate host, including ease of breeding, ease of handling, a competent innate immune system, and the ability to survive at 37°C. MH cockroaches were highly susceptible to infection with B. pseudomallei, B. mallei and B. thailandensis and the LD50 was <10 colony-forming units (cfu) for all three species. In comparison, the LD50 for Escherichia coli in MH cockroaches was >105?cfu. B. pseudomallei, B. mallei, and B. thailandensis cluster 1 type VI secretion system (T6SS-1) mutants were all attenuated in MH cockroaches, which is consistent with previous virulence studies conducted in rodents. B. pseudomallei mutants deficient in the other five T6SS gene clusters, T6SS-2 through T6SS-6, were virulent in both MH cockroaches and hamsters. Hemocytes obtained from MH cockroaches infected with B. pseudomallei harbored numerous intracellular bacteria, suggesting that this facultative intracellular pathogen can survive and replicate inside of MH cockroach phagocytic cells. The hemolymph extracted from these MH cockroaches also contained multinuclear giant cells (MNGCs) with intracellular B. pseudomallei, which indicates that infected hemocytes can fuse while flowing through the insect’s open circulatory system in vivo. Conclusions The results demonstrate that MH cockroaches are an attractive alternative to mammals to study host-pathogen interactions and may allow the identification of new Burkholderia virulence determinants. The importance of T6SS-1 as a virulence factor in MH cockroaches and rodents suggests that the primary role of this secretion system is to target evasion of the innate immune system. PMID:22892068

2012-01-01

370

Campylobacter infection in a cohort of rural children in Moramanga, Madagascar  

PubMed Central

Background Campylobacter infection is the most common cause of bacterial gastroenteritis in developing countries, including Madagascar. Reports of pathogenicity have not been consistent and repeated exposures over time seem to lead to the development of protective immunity in developing areas. We conducted this study to support evidence for these hypotheses by exploring the association between infection and age, the reoccurrence of infection and the pathogenicity of Campylobacter. Methods We carried out a community-based longitudinal study of children under the age of 24 months in two rural villages in Moramanga, Madagascar. Children were visited twice a week and a stool specimen was collected in cases of diarrhoea. Stools specimens were collected bimonthly from all children enrolled, regardless of symptoms. Children were followed-up until the age of 36 months. Results Between January 2010 and May 31st 2012, 508 children were included in the cohort. We detected 319 episodes of Campylobacter infection in total, and 43.3% (n?=?220) of the children had at least one episode of intestinal Campylobacter infection. The rate of Campylobacter isolation from stool specimens was 9.3%. The annual incidence rate for symptomatic Campylobacter infection was 0.05 episodes/child. The probability of Campylobacter infection was highest between the ages of six and 23 months. Taking children under six months of age as the reference group, the age-specific odds ratio for the association was 5.0 (95% CI: 2.9-8.6) for children aged six to 11 months, 5.7 (95% CI: 3.3-10.0) for children aged 12 to 17 months and 3.3 (95% CI: 1.8-5.8) for children aged 18 to 23 months. A second episode of infection occurred 63 days after the first episode in children with primary infections, and after 137 days in children with multiple infections (p?

2014-01-01

371

Air pollution studies in terms of PM2.5, PM2.5-10, PM10, lead and black carbon in urban areas of Antananarivo - Madagascar  

E-print Network

Atmospheric aerosols or particulate matters are chemically complex and dynamic mixtures of solid and liquid particles. Sources of particulate matters include both natural and anthropogenic processes. The present work consists in determining the concentrations of existing elements in the aerosols collected in Andravoahangy and in Ambodin'Isotry in Antananarivo city (Madagascar). The size distribution of these elements and their main sources are also studied. The Total Reflection X-Ray Fluorescence spectrometer is used for the qualitative and quantitative analyses. The results show that the concentrations of the airborne particulate matters PM2.5-10 are higher than those of PM2.5. The identified elements in the aerosol samples are Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr and Pb. The average concentrations of these elements are also higher in the coarse particles than in the fine particles. The calculation of the enrichment factors by Mason's model shows that Cr, Ni, Cu, Zn, Br and Pb are of anthropogenic origins. The...

Rasoazanany, E O; Ravoson, H N; Andriambololona, Raoelina; Randriamanivo, L V; Ramaherison, H; Ahmed, H; Harinoely, M

2012-01-01

372

Insights on the evolution of plant succulence from a remarkable radiation in Madagascar (Euphorbia).  

PubMed

Patterns of adaptation in response to environmental variation are central to our understanding of biodiversity, but predictions of how and when broad-scale environmental conditions such as climate affect organismal form and function remain incomplete. Succulent plants have evolved in response to arid conditions repeatedly, with various plant organs such as leaves, stems, and roots physically modified to increase water storage. Here, we investigate the role played by climate conditions in shaping the evolution of succulent forms in a plant clade endemic to Madagascar and the surrounding islands, part of the hyper-diverse genus Euphorbia (Euphorbiaceae). We used multivariate ordination of 19 climate variables to identify links between particular climate variables and three major forms of succulence-succulent leaves, cactiform stem succulence, and tubers. We then tested the relationship between climatic conditions and succulence, using comparative methods that account for shared evolutionary history. We confirm that plant water storage is associated with the two components of aridity, temperature, and precipitation. Cactiform stem succulence, however, is not prevalent in the driest environments, countering the widely held view of cactiforms as desert icons. Instead, leaf succulence and tubers are significantly associated with the lowest levels of precipitation. Our findings provide a clear link between broad-scale climatic conditions and adaptation in land plants, and new insights into the climatic conditions favoring different forms of succulence. This evidence for adaptation to climate raises concern over the evolutionary future of succulent plants as they, along with other organisms, face anthropogenic climate change. PMID:24852061

Evans, Margaret; Aubriot, Xavier; Hearn, David; Lanciaux, Maxime; Lavergne, Sebastien; Cruaud, Corinne; Lowry, Porter P; Haevermans, Thomas

2014-09-01

373

Polyphase Neoproterozoic orogenesis within the east Africa- Antarctica orogenic belt in central and northern Madagascar  

USGS Publications Warehouse

Our recent geological survey of the basement of central and northern Madagascar allowed us to re-evaluate the evolution of this part of the East Africa-Antarctica Orogen (EAAO). Five crustal domains are recognized, characterized by distinctive lithologies and histories of sedimentation, magmatism, deformation and metamorphism, and separated by tectonic and/or unconformable contacts. Four consist largely of Archaean metamorphic rocks (Antongil, Masora and Antananarivo Cratons, Tsaratanana Complex). The fifth (Bemarivo Belt) comprises Proterozoic meta-igneous rocks. The older rocks were intruded by plutonic suites at c. 1000 Ma, 820-760 Ma, 630-595 Ma and 560-520 Ma. The evolution of the four Archaean domains and their boundaries remains contentious, with two end-member interpretations evaluated: (1) all five crustal domains are separate tectonic elements, juxtaposed along Neoproterozoic sutures and (2) the four Archaean domains are segments of an older Archaean craton, which was sutured against the Bemarivo Belt in the Neoproterozoic. Rodinia fragmented during the early Neoproterozoic with intracratonic rifts that sometimes developed into oceanic basins. Subsequent Mid- Neoproterozoic collision of smaller cratonic blocks was followed by renewed extension and magmatism. The global 'Terminal Pan-African' event (560-490 Ma) finally stitched together the Mid-Neoproterozoic cratons to form Gondwana. ?? The Geological Society of London 2011.

Key, R.M.; Pitfield, P.E.J.; Thomas, Ronald J.; Goodenough, K.M.; Waele, D.; Schofield, D.I.; Bauer, W.; Horstwood, M.S.A.; Styles, M.T.; Conrad, J.; Encarnacion, J.; Lidke, D.J.; O'connor, E. A.; Potter, C.; Smith, R.A.; Walsh, G.J.; Ralison, A.V.; Randriamananjara, T.; Rafahatelo, J.-M.; Rabarimanana, M.

2011-01-01

374

Comparative and population mitogenomic analyses of Madagascar's extinct, giant 'subfossil' lemurs.  

PubMed

Humans first arrived on Madagascar only a few thousand years ago. Subsequent habitat destruction and hunting activities have had significant impacts on the island's biodiversity, including the extinction of megafauna. For example, we know of 17 recently extinct 'subfossil' lemur species, all of which were substantially larger (body mass ?11-160 kg) than any living population of the ?100 extant lemur species (largest body mass ?6.8 kg). We used ancient DNA and genomic methods to study subfossil lemur extinction biology and update our understanding of extant lemur conservation risk factors by i) reconstructing a comprehensive phylogeny of extinct and extant lemurs, and ii) testing whether low genetic diversity is associated with body size and extinction risk. We recovered complete or near-complete mitochondrial genomes from five subfossil lemur taxa, and generated sequence data from population samples of two extinct and eight extant lemur species. Phylogenetic comparisons resolved prior taxonomic uncertainties and confirmed that the extinct subfossil species did not comprise a single clade. Genetic diversity estimates for the two sampled extinct species were relatively low, suggesting small historical population sizes. Low genetic diversity and small population sizes are both risk factors that would have rendered giant lemurs especially susceptible to extinction. Surprisingly, among the extant lemurs, we did not observe a relationship between body size and genetic diversity. The decoupling of these variables suggests that risk factors other than body size may have as much or more meaning for establishing future lemur conservation priorities. PMID:25523037

Kistler, Logan; Ratan, Aakrosh; Godfrey, Laurie R; Crowley, Brooke E; Hughes, Cris E; Lei, Runhua; Cui, Yinqiu; Wood, Mindy L; Muldoon, Kathleen M; Andriamialison, Haingoson; McGraw, John J; Tomsho, Lynn P; Schuster, Stephan C; Miller, Webb; Louis, Edward E; Yoder, Anne D; Malhi, Ripan S; Perry, George H

2015-02-01

375

Extreme vulnerability of smallholder farmers to agricultural risks and climate change in Madagascar.  

PubMed

Across the tropics, smallholder farmers already face numerous risks to agricultural production. Climate change is expected to disproportionately affect smallholder farmers and make their livelihoods even more precarious; however, there is limited information on their overall vulnerability and adaptation needs. We conducted surveys of 600 households in Madagascar to characterize the vulnerability of smallholder farmers, identify how farmers cope with risks and explore what strategies are needed to help them adapt to climate change. Malagasy farmers are particularly vulnerable to any shocks to their agricultural system owing to their high dependence on agriculture for their livelihoods, chronic food insecurity, physical isolation and lack of access to formal safety nets. Farmers are frequently exposed to pest and disease outbreaks and extreme weather events (particularly cyclones), which cause significant crop and income losses and exacerbate food insecurity. Although farmers use a variety of risk-coping strategies, these are insufficient to prevent them from remaining food insecure. Few farmers have adjusted their farming strategies in response to climate change, owing to limited resources and capacity. Urgent technical, financial and institutional support is needed to improve the agricultural production and food security of Malagasy farmers and make their livelihoods resilient to climate change. PMID:24535397

Harvey, Celia A; Rakotobe, Zo Lalaina; Rao, Nalini S; Dave, Radhika; Razafimahatratra, Hery; Rabarijohn, Rivo Hasinandrianina; Rajaofara, Haingo; Mackinnon, James L

2014-04-01

376

Biomedical evaluation of black lemurs (Eulemur macaco macaco) in Lokobe Reserve, Madagascar.  

PubMed

Complete medical evaluations were performed on 25 wild black lemurs (Eulemur macaco macaco) in Lokobe Reserve, northwestern Madagascar. Each animal received a complete physical examination. Weight, body temperature, heart rate, and respiratory rate were recorded. Blood samples were collected for complete blood cell count, differential white blood cell count, hemoparasite examination, serum biochemical profile, fat-soluble vitamin analysis, trace mineral analysis, and Toxoplasma gondii and viral serology. Fecal samples were collected for bacterial culture and endoparasite examination. Ectoparasites were collected and identified. Values were compared to established ranges from captive black lemurs in North American zoos. Significant differences exist between captive and wild animals for total white blood cell count, segmented neutrophil count, band neutrophil count, eosinophil count, monocyte count, and basophil count, and for serum biochemistry values of aspartate aminotransferase, alanine aminotransferase, total bilirubin, serum alkaline phosphatase, total protein, creatinine, phosphorus, calcium, sodium, potassium, and creatine phosphokinase. One animal had a positive Toxoplasma titer. Detected endoparasites were identified as Lemuricola and Callistroura. Two ectoparasite mites were identified, one within the Psoroptes genus and one within the Laelapidae family. Enteric bacterial flora included Enterococcus sp., Staphylococcus sp., Escherichia coli, Streptococcus sp., Klebsiella ozaenae and Bacillus cereus. PMID:17469278

Junge, Randall E; Louis, Edward E

2007-03-01

377

Profil épidemio-clinique et radiologique des atteintes ostéo-articulaires des hémophiles à Madagascar  

PubMed Central

Introduction Déterminer le profil épidémio-clinique et radiologique des atteintes ostéo-articulaires des hémophiles malagasy. Méthodes Une étude prospective, descriptive portant sur 25 patients hémophiles venant de tout Madagascar a été réalisée. Des radiographies numérisées des genoux, des chevilles et des coudes en incidence de face et de profil ainsi qu'une échographie des hanches, des genoux, des chevilles et des coudes ont été réalisées chez ces patients. Le type et la sévérité de la maladie ainsi que l'aspect de la cavité articulaire, la synoviale, les noyaux épiphysaires et les surfaces articulaires ont été analysés. Résultats Soixante-huit pourcent des patients étaient hémophiles de type A et 32 % de type B. Quarante pourcent étaient classés sévères, 28 % modérés et 32 % mineurs. Les atteintes ostéo-articulaires ont été retrouvées chez 56 % des patients. Il n'existait pas de prédominance d'atteinte selon le type ni la sévérité de la maladie. Les plus jeunes étaient les plus atteints et l'articulation du genou et de la cheville étaient les plus touchées. Conclusion Les complications ostéo-articulaire de l'hémophilie sont graves et ne dépendent pas du type ni de la sévérité de l'affection. Elles touchent surtout les enfants d'âge scolaire. Le couple radiographie-échographie permet de diagnostiquer et de surveiller ces lésions.

Narindra, Lova Hasina Rajaonarison Ny Ony; Rabemanorintsoa, Feno Hasina; Randrianantenaina, Faralahy Ravelonarivo; Rakoto, Olivat Alson Aimée; Ahmad, Ahmad

2014-01-01

378

Census of brown lemurs (Eulemur fulvus sspp.) in southeastern Madagascar: methods-testing and conservation implications.  

PubMed

Four forest areas were censused in southeastern Madagascar from June-August 1995 to estimate local population densities and habitat conditions for two threatened subspecies of brown lemur (Eulemur fulvus collaris and Eulemur fulvus albocollaris). Survey transects varied in length (1-3.5 km) and in surveillance frequency (three to seven times). Additional test surveys were conducted at the Parc National de Ranomafana to compare transect methods in an area with known population densities of Eulemur fulvus. Based on these tests, we demonstrate that the use of existing trails for transects can result in a close estimate of local population size, although more replications and longer transects increase precision. Results from regional surveys indicate considerably smaller population densities for E. f. albocollaris (0.086 animals/ha). In contrast, E. f. collaris densities were relatively high (.107 animals/ha) at Midongy-Sud. We also noted variation among sites in the density of lianas, which was positively correlated with local population density (a possible indication of habitat degradation). More generally, habitats in E. f. albocollaris's range suffered from fragmentation, reduction in forest area, logging, and potentially greater hunting pressure. Based on these results, it is apparent that more immediate steps are necessary to preserve E. f. albocollaris populations and habitats. PMID:9888721

Johnson, S E; Overdorff, D J

1999-01-01

379

Post-collisional magmatism in the central East African Orogen: The Maevarano Suite of north Madagascar  

USGS Publications Warehouse

Late tectonic, post-collisional granite suites are a feature of many parts of the Late Neoproterozoic to Cambrian East African Orogen (EAO), where they are generally attributed to late extensional collapse of the orogen, accompanied by high heat flow and asthenospheric uprise. The Maevarano Suite comprises voluminous plutons which were emplaced in some of the tectonostratigraphic terranes of northern Madagascar, in the central part of the EAO, following collision and assembly during a major orogeny at ca. 550 Ma. The suite comprises three main magmatic phases: a minor early phase of foliated gabbros, quartz diorites, and granodiorites; a main phase of large batholiths of porphyritic granitoids and charnockites; and a late phase of small-scale plutons and sheets of monzonite, syenite, leucogranite and microgranite. The main phase intrusions tend to be massive, but with variably foliated margins. New U-Pb SHRIMP zircon data show that the whole suite was emplaced between ca. 537 and 522 Ma. Geochemically, all the rocks of the suite are enriched in the LILE, especially K, and the LREE, but are relatively depleted in Nb, Ta and the HREE. These characteristics are typical of post-collisional granitoids in the EAO and many other orogenic belts. It is proposed that the Maevarano Suite magmas were derived by melting of sub-continental lithospheric mantle that had been enriched in the LILE during earlier subduction events. The melting occurred during lithospheric delamination, which was associated with extensional collapse of the East African Orogen. ?? 2009 Natural Environment Research Council.

Goodenough, K.M.; Thomas, Ronald J.; De Waele, B.; Key, R.M.; Schofield, D.I.; Bauer, W.; Tucker, R.D.; Rafahatelo, J.-M.; Rabarimanana, M.; Ralison, A.V.; Randriamananjara, T.

2010-01-01

380

Geometry and kinematics of the late Proterozoic Angavo Shear Zone, Central Madagascar: Implications for Gondwana Assembly  

NASA Astrophysics Data System (ADS)

This paper documents the 20 to 60 km wide N-S trending Angavo Shear Zone (ASZ) in central Madagascar and its tectonic implications by examining its structural styles, kinematics and geometry. Our study indicates that the ASZ is characterized by at least two ductile Late Proterozoic deformation events (D1 and D2) followed by a brittle neotectonic deformation (D3). The early D1 event produced a regionally extensive S1 foliation, stretching/flattening mineral lineation L1 and symmetrical structural fabrics such as recumbent and isoclinal intra-folial folds (F1), implying a flattening deformation. D1 deformational fabrics are locally overprinted by D2 structures. D2 is characterized by a penetrative S2 foliation, shallow south plunging L2 lineation, asymmetric and sheath folds (F2) consistent with a right lateral sense of movement exhibited by delta- and sigma-type porphyroclast systems and asymmetric boudinage fabrics. D2 represents a non-coaxial flow regime formed in a dextral west over east shear zone during a partitioned transpression in response to east-west-directed compression during the assembly of Gondwana. A close resemblance with the Achankovil shear zone in India is noticed; however the continuation of the ASZ in Africa is uncertain.

Raharimahefa, Tsilavo; Kusky, Timothy M.; Toraman, Erkan; Rasoazanamparany, Christine; Rasaonina, Imboarina

2013-04-01

381

Complex epidemiology and zoonotic potential for Cryptosporidium suis in rural Madagascar.  

PubMed

Cryptosporidium spp. is the most important parasitic diarrheal agent in the world, is among the top four causes of moderate-to-severe diarrheal disease in young children in developing nations, and is problematic as an opportunistic co-infection with HIV. In addition, Cryptosporidium is a persistent challenge for livestock production. Despite its zoonotic potential, few studies have examined the ecology and epidemiology of this pathogen in rural systems characterized by high rates of overlap among humans, domesticated animals, and wildlife. To improve our understanding of the zoonotic potential of Cryptosporidium species in the rural tropics, we screened humans, livestock, peridomestic rodents, and wildlife using PCR-RFLP and sequencing-based approaches to distinguish species of Cryptosporidium in rural southeastern Madagascar. Cryptosporidium of multiple species/genotypes were apparent in this study system. Interestingly, C. suis was the dominant species of Cryptosporidium in the region, infecting humans (n=1), cattle (n=18), pigs (n=3), and rodents (n=1). The broad species range of C. suis and the lack of common cattle Cryptosporidium species (Cryptosporidium parvum and Cryptosporidium andersoni) in this system are unique. This report represents the fifth confirmed case of C. suis infection in humans, and the first case in Africa. Few rural human and livestock populations have been screened for Cryptosporidium using genus-specific genotyping methods. Consequently, C. suis may be more widespread in human and cattle populations than previously believed. PMID:25481280

Bodager, Jonathan R; Parsons, Michele B; Wright, Patricia C; Rasambainarivo, Fidisoa; Roellig, Dawn; Xiao, Lihua; Gillespie, Thomas R

2015-01-15

382

Bartonella spp. in Fruit Bats and Blood-Feeding Ectoparasites in Madagascar  

PubMed Central

We captured, ectoparasite-combed, and blood-sampled cave-roosting Madagascan fruit bats (Eidolon dupreanum) and tree-roosting Madagascan flying foxes (Pteropus rufus) in four single-species roosts within a sympatric geographic foraging range for these species in central Madagascar. We describe infection with novel Bartonella spp. in sampled Eidolon dupreanum and associated bat flies (Cyclopodia dubia), which nest close to or within major known Bartonella lineages; simultaneously, we report the absence of Bartonella spp. in Thaumapsylla sp. fleas collected from these same bats. This represents the first documented finding of Bartonella infection in these species of bat and bat fly, as well as a new geographic record for Thaumapsylla sp. We further relate the absence of both Bartonella spp. and ectoparasites in sympatrically sampled Pteropus rufus, thus suggestive of a potential role for bat flies in Bartonella spp. transmission. These findings shed light on transmission ecology of bat-borne Bartonella spp., recently demonstrated as a potentially zoonotic pathogen. PMID:25706653

Brook, Cara E.; Bai, Ying; Dobson, Andrew P.; Osikowicz, Lynn M.; Ranaivoson, Hafaliana C.; Zhu, Qiyun

2015-01-01

383

Plasmodium vivax Resistance to Chloroquine in Madagascar: Clinical Efficacy and Polymorphisms in pvmdr1 and pvcrt-o Genes?  

PubMed Central

No data were available concerning Plasmodium vivax resistance to chloroquine (CQ) in Madagascar. We investigated the therapeutic efficacy of CQ in P. vivax malaria, the prevalence of mutations in the pvcrt-o and pvmdr1 genes before treatment, and the association between mutant parasites and the clinical response of the patients to CQ treatment. Clinical isolates were collected at six sentinel sites located in the three epidemiological strata for malaria throughout Madagascar in 2006. Patients were enrolled, treated, and followed up according to the WHO 2001 guidelines for P. vivax infections. Sequencing was used to analyze polymorphisms of the pvcrt-o (exons 1 to 6) and pvmdr1 genes. The treatment failure rate, after adjustment for genotyping, was estimated at 5.1% for the 105 patients included, ranging from zero in the South to 14.8% in the foothills of the Central Highlands. All samples were wild type for pvcrt-o but mutant for the pvmdr1 gene. Ten nonsynonymous mutations were found in the pvmdr1 gene, including five new mutations, four of which were present at low frequencies (1.3% to 7.5%) while the S513R mutation was present at a much higher frequency (96.3%). The other five mutations, including Y976F, had been described before and had frequencies of 97.8% to 100%. Our findings suggest that CQ-resistant P. vivax isolates are present in Madagascar, particularly in the foothills of the Central Highlands. The 976Y pvmdr1 mutation was found not to be useful for monitoring CQ resistance. Further efforts are required to develop suitable tools for monitoring drug resistance in P. vivax malaria. PMID:18809933

Barnadas, Céline; Ratsimbasoa, Arsène; Tichit, Magali; Bouchier, Christiane; Jahevitra, Martial; Picot, Stéphane; Ménard, Didier

2008-01-01

384

Microscopic and molecular characterization of Hepatozoon domerguei (Apicomplexa) and Foleyella furcata (Nematoda) in wild endemic reptiles from Madagascar  

PubMed Central

Madagascar is one of the world’s top twelve “megadiversity” hot spots hosting unique and threatened flora and fauna. Parasites are a major component of biodiversity but remain largely uncharacterized in wildlife. In this study we combine microscopic and molecular assessment of hemoparasites in endemic reptile species from Madagascar. We detected three distinct parasites: the apicomplexans Hepatozoon and Sarcocystis, and filarial nematodes. The prevalence and intensity of these apicomplexans were low overall, while microfilarial infections in chameleons were relatively high. We detected mixed infections of two Hepatozoon haplotypes in Madagascarophis colubrinus, and of Hepatozoon and microfilariae in a Furcifer sp. Phylogenetic analyses of Hepatozoon showed evidence of prey-predator transmission, with identical sequences found in the snakes M. colubrinus and Ithycyphus oursi, and their prey Furcifer sp. Based on previous studies regarding the life cycle of Hepatozoon domerguei Landau, Chabaud, Michel, and Brygoo, 1970 in these hosts and due to their morphological similarity, we propose that this Hepatozoon haplotype is Hepatozoon domerguei. Future studies, including the examination of invertebrate hosts, are needed to verify this preliminary taxonomic identification. A distinct hemogregarine haplotype was found in Oplurus sp., which displayed morphologically different gametocytes, some of which were apparently inside leukocytes. The Sarcocystis identified from Tracheloptychus petersi was identical to that reported in a North African snake, indicating that the same lineage is found in geographically distinct regions. By combining morphological and genetic information, Foleyella furcata (Linstow, 1899) filarial nematodes were identified in several Furcifer chameleons. This study provides insights into the distribution, diversity and host-parasite interactions of hemoparasites in wild reptile populations from Madagascar. PMID:25224723

Maia, João P.; Crottini, Angelica; Harris, David James

2014-01-01

385

Microscopic and molecular characterization of Hepatozoon domerguei (Apicomplexa) and Foleyella furcata (Nematoda) in wild endemic reptiles from Madagascar.  

PubMed

Madagascar is one of the world's top twelve "megadiversity" hot spots hosting unique and threatened flora and fauna. Parasites are a major component of biodiversity but remain largely uncharacterized in wildlife. In this study we combine microscopic and molecular assessment of hemoparasites in endemic reptile species from Madagascar. We detected three distinct parasites: the apicomplexans Hepatozoon and Sarcocystis, and filarial nematodes. The prevalence and intensity of these apicomplexans were low overall, while microfilarial infections in chameleons were relatively high. We detected mixed infections of two Hepatozoon haplotypes in Madagascarophis colubrinus, and of Hepatozoon and microfilariae in a Furcifer sp. Phylogenetic analyses of Hepatozoon showed evidence of prey-predator transmission, with identical sequences found in the snakes M. colubrinus and Ithycyphus oursi, and their prey Furcifer sp. Based on previous studies regarding the life cycle of Hepatozoon domerguei Landau, Chabaud, Michel, and Brygoo, 1970 in these hosts and due to their morphological similarity, we propose that this Hepatozoon haplotype is Hepatozoon domerguei. Future studies, including the examination of invertebrate hosts, are needed to verify this preliminary taxonomic identification. A distinct hemogregarine haplotype was found in Oplurus sp., which displayed morphologically different gametocytes, some of which were apparently inside leukocytes. The Sarcocystis identified from Tracheloptychus petersi was identical to that reported in a North African snake, indicating that the same lineage is found in geographically distinct regions. By combining morphological and genetic information, Foleyella furcata (Linstow, 1899) filarial nematodes were identified in several Furcifer chameleons. This study provides insights into the distribution, diversity and host-parasite interactions of hemoparasites in wild reptile populations from Madagascar. PMID:25224723

Maia, João P; Crottini, Angelica; Harris, David James

2014-01-01

386

New species from the Galoka and Kalabenono massifs: two unknown and severely threatened mountainous areas in NW Madagascar  

PubMed Central

The Galoka mountain chain, comprising principally the Galoka and Kalabenono massifs, situated at the northern edge of the Sambirano Region in NW Madagascar is an area that was virtually unknown botanically. It was visited three times between 2005 and 2007 as part of a floristic inventory. Both massifs contain the last remaining primary forests in the Galoka chain, which extends parallel to the coastline from South of Ambilobe to North of Ambanja. Several new species have been discovered amongst the collections, eight of which are described here. PMID:21857767

Callmander, Martin W.; Rakotovao, Charles; Razafitsalama, Jeremi; Phillipson, Peter B.; Buerki, Sven; Hong-Wa, Cynthia; Rakotoarivelo, Nivo; Andriambololonera, Sylvie; Koopman, Margaret M.; Johnson, David M.; Deroin, Thierry; Ravoahangy, Andriamandranto; Solo, Serge; Labat, Jean-Noël; Lowry, Porter P.

2011-01-01

387

The endophyte Curtobacterium flaccumfaciens reduces symptoms caused by Xylella fastidiosa in Catharanthus roseus.  

PubMed

Citrus variegated chlorosis (CVC) is a disease of the sweet orange [Citrus sinensis (L.)], which is caused by Xylella fastidiosa subsp. pauca, a phytopathogenic bacterium that has been shown to infect all sweet orange cultivars. Sweet orange trees have been occasionally observed to be infected by Xylella fastidiosa without evidencing severe disease symptoms, whereas other trees in the same grove may exhibit severe disease symptoms. The principal endophytic bacterial species isolated from such CVC-asymptomatic citrus plants is Curtobacterium flaccumfaciens. The Madagascar periwinkle [Citrus sinensis (L.)] is a model plant which has been used to study X. fastidiosa in greenhouse environments. In order to characterize the interactions of X. fastidiosa and C. flaccumfaciens, periwinkle plants were inoculated separately with C. flaccumfaciens, X. fastidiosa, and both bacteria together. The number of flowers produced by the plants, the heights of the plants, and the exhibited disease symptoms were evaluated. PCR-primers for C. flaccumfaciens were designed in order to verify the presence of this endophytic bacterium in plant tissue, and to complement an existing assay for X. fastidiosa. These primers were capable of detecting C. flaccumfaciens in the periwinkle in the presence of X. fastidiosa. X. fastidiosa induced stunting and reduced the number of flowers produced by the periwinkle. When C. flaccumfaciens was inoculated together with X. fastidiosa, no stunting was observed. The number of flowers produced by our doubly- inoculated plants was an intermediate between the number produced by the plants inoculated with either of the bacteria separately. Our data indicate that C. flaccumfaciens interacted with X. fastidiosa in C. roseus, and reduced the severity of the disease symptoms induced by X. fastidiosa. Periwinkle is considered to be an excellent experimental system by which the interaction of C. flaccumfaciens and other endophytic bacteria with X. fastidiosa can be studied. PMID:17978797

Lacava, Paulo Teixeira; Li, Wenbin; Araújo, Welington Luiz; Azevedo, João Lúcio; Hartung, John Stephen

2007-10-01

388

A refined chronology of prehistoric Madagascar and the demise of the megafauna  

NASA Astrophysics Data System (ADS)

The vertebrate community of Madagascar is one of the most unique and diverse on Earth, yet faunal diversity today is just a fraction of that present in the Pleistocene and Early Holocene. An understanding of the chronology of extinction relative to climate change and anthropogenic factors is essential to test hypotheses for extinction. Here, I combine over 200 new radiocarbon dates with published 14C dates from extinct and extant subfossil vertebrates. These new data provide evidence for the prolonged existence of both extant and extinct endemic terrestrial vertebrate species well before human arrival, with habitation of some localities extending back before the Last Glacial Maximum. I analyze the data for patterns among body sizes and ecoregions in relation to four major historical events: human arrival (ca 2500 years ago), establishment of human settlements (ca 1500 years ago), Late Holocene aridification (peaking ca 1000 years ago), and European arrival (ca 500 years ago). Patterns in endemic species abundance after human arrival differ depending on body size and geographic location. Within the first 500 years after human arrival, there were population declines in (1) very large species (>150 kg) and large species (10-150 kg) in the Dry Deciduous Forest, (2) large species in the Central Highlands, and (3) very large species in the Spiny Thicket. This first pulse of declines was likely triggered by human predation. Large species continued to be well represented in the Spiny Thicket and Succulent Woodland until ca 1000 years ago, when their populations plummeted. This second pulse of declines may have been solely triggered by continued human predation, or it may have resulted from a combination of increasing Late Holocene aridity and human impacts in the form of hunting and habitat modification. The abundance of endemic animals weighing <10 kg increased dramatically in the aftermath of the decline in large-bodied species.

Crowley, Brooke E.

2010-09-01

389

Successful contracting of prevention services: fighting malnutrition in Senegal and Madagascar.  

PubMed

There are very few documented large-scale successes in nutrition in Africa, and virtually no consideration of contracting for preventive services. This paper describes two successful large-scale community nutrition projects in Africa as examples of what can be done in prevention using the contracting approach in rural as well as urban areas. The two case-studies are the Secaline project in Madagascar, and the Community Nutrition Project in Senegal. The article explains what is meant by 'success' in the context of these two projects, how these results were achieved, and how certain bottlenecks were avoided. Both projects are very similar in the type of service they provide, and in combining private administration with public finance. The article illustrates that contracting out is a feasible option to be seriously considered for organizing certain prevention programmes on a large scale. There are strong indications from these projects of success in terms of reducing malnutrition, replicability and scale, and community involvement. When choosing that option, a government can tap available private local human resources through contracting out, rather than delivering those services by the public sector. However, as was done in both projects studied, consideration needs to be given to using a contract management unit for execution and monitoring, which costs 13-17% of the total project's budget. Rigorous assessments of the cost-effectiveness of contracted services are not available, but improved health outcomes, targeting of the poor, and basic cost data suggest that the programmes may well be relatively cost-effective. Although the contracting approach is not presented as the panacea to solve the malnutrition problem faced by Africa, it can certainly provide an alternative in many countries to increase coverage and quality of services. PMID:10787654

Marek, T; Diallo, I; Ndiaye, B; Rakotosalama, J

1999-12-01

390

Petrology of ultramafic xenoliths in Cenozoic alkaline rocks of northern Madagascar (Nosy Be Archipelago)  

NASA Astrophysics Data System (ADS)

Late Miocene basanites of Nosy Be and Nosy Sakatia islands (Nosy Be Archipelago, northern Madagascar) carry spinel-facies anhydrous ultramafic xenoliths (lherzolites, harzburgites and wehrlites). Geothermobarometric estimates indicate that these xenoliths derive from shallow mantle depths of 35-40 km, with those from Nosy Be island showing equilibration T (averages in the range of 945-985 °C) lower than the Nosy Sakatia analogues (averages ranging from 1010 to 1110 °C). One Nosy Sakatia mantle xenolith exhibits relatively fertile lherzolite composition, with trace and major element mineral chemistry consistent with a residual character after low degrees (1-2%) of mafic melt extraction. We interpret this composition as that resembling a depleted mantle (DM)-like lithospheric composition before metasomatic overprints. The other lherzolites and harzburgites display petrochemical characters consistent with variable extent of partial melting (up to 18%), associated with pronounced metasomatic overprints caused by migrating melts, as highlighted by enrichments in highly incompatible trace elements (e.g. light rare earth elements, LREE and Sr), together with the abundant occurrence of wehrlitic lithologies. The variability of petrochemical features points to different styles of metasomatism and metasomatic agents. The estimated composition of the parental melts of wehrlites matches that of host basanites. The combination of this evidence with the petrographic features, characterized by coarse-granular to porphyroclastic textures and by the presence of olivine without kink-banding, suggests that wehrlites are veins or pockets of high pressure cumulates within the mantle peridotite. The same melts also metasomatized via porous-flow percolation some lherzolites and harzburgites. Distinctly, a group of lherzolites and harzburgites was metasomatized by a different alkaline melt having markedly lower incompatible trace element contents. Late infiltration of metasomatic fluids is responsible for the spongy texture of some clinopyroxenes of lherzolites, harzburgites and wehrlites.

Rocco, Ivana; Lustrino, Michele; Zanetti, Alberto; Morra, Vincenzo; Melluso, Leone

2013-01-01

391

Renaud Paulian et le programme du CNRS sur les hautes montagnes à Madagascar: étage vs domaine  

PubMed Central

Résumé Le programme intitulé « Étude des écosystémes montagnards dans la région malgache» (RCP 225/CNRS; responsable: Recteur Renaud Paulian) avait pour ambition de dégager leurs caractères généraux, l'origine des éléments constitutifs et de tester la validité d'un Domaine malgache des Hautes Montagnes proposé par Humbert dès 1951. De 1970 à 1973, trois campagnes (Andringitra; Chaînes anosyennes et Ankaratra; Itremo, Ibity et Marojejy) ont permis une caractérisation écologique des milieux particuliers ainsi que des analyses de systématique sur certains taxa connus pour leur intérêt biogéographique. La succession altitudinale des formations végétales, définies par des critères physionomiques et structuraux, est précisée par massif. Le dernier étage caractérisé par le fourré éricoïde et ses groupements associés ne correspond pas à l'Étage des Hautes Montagnes de l'Est africain. Des groupes de la faune (invertébrés hexapodes: Collemboles et Dermaptères) indiquent une disjonction entre les massifs du Nord (Tsaratanana, Marojejy), ceux du Centre et du Sud; des éléments de la flore (Pandanaceae, Araliaceae, Asteraceae) sont en cours d'analyse dans le même sens. Le Domaine des Hautes montagnes à Madagascar est une réalité écologique mais ne peut être défini floristiquement; chaque massif montagneux est une entité phytogéographique d'étages de végétation interdépendants inclus dans les différents Sous-Domaines du Centre. Les groupes peu mobiles de la faune indiquent globalement une dépendance trophique et bioclimatique (effet tampon du climat intraforestier) vis-à-vis des étages de végétation, mais peuvent réagir à des microclimats locaux par des décalages à leurs limites. PMID:21731422

Guillaumet, Jean-Louis; Betsch, Jean-Marie; Callmander, Martin W.

2011-01-01

392

Patterns of Loss and Regeneration of Tropical Dry Forest in Madagascar: The Social Institutional Context  

PubMed Central

Loss of tropical forests and changes in land-use/land-cover are of growing concern worldwide. Although knowledge exists about the institutional context in which tropical forest loss is embedded, little is known about the role of social institutions in influencing regeneration of tropical forests. In the present study we used Landsat images from southern Madagascar from three different years (1984, 1993 and 2000) and covering 5500 km2, and made a time-series analysis of three distinct large-scale patterns: 1) loss of forest cover, 2) increased forest cover, and 3) stable forest cover. Institutional characteristics underlying these three patterns were analyzed, testing the hypothesis that forest cover change is a function of strength and enforcement of local social institutions. The results showed a minor decrease of 7% total forest cover in the study area during the whole period 1984–2000, but an overall net increase of 4% during the period 1993–2000. The highest loss of forest cover occurred in a low human population density area with long distances to markets, while a stable forest cover occurred in the area with highest population density and good market access. Analyses of institutions revealed that loss of forest cover occurred mainly in areas characterized by insecure property rights, while areas with well-defined property rights showed either regenerating or stable forest cover. The results thus corroborate our hypothesis. The large-scale spontaneous regeneration dominated by native endemic species appears to be a result of a combination of changes in precipitation, migration and decreased human population and livestock grazing pressure, but under conditions of maintained and well-defined property rights. Our study emphasizes the large capacity of a semi-arid system to spontaneously regenerate, triggered by decreased pressures, but where existing social institutions mitigate other drivers of deforestation and alternative land-use. PMID:17476324

Elmqvist, Thomas; Pyykönen, Markku; Tengö, Maria; Rakotondrasoa, Fanambinantsoa; Rabakonandrianina, Elisabeth; Radimilahy, Chantal

2007-01-01

393

Phylogenomics and taxonomy of Lecomtelleae (Poaceae), an isolated panicoid lineage from Madagascar  

PubMed Central

Background and Aims An accurate characterization of biodiversity requires analyses of DNA sequences in addition to classical morphological descriptions. New methods based on high-throughput sequencing may allow investigation of specimens with a large set of genetic markers to infer their evolutionary history. In the grass family, the phylogenetic position of the monotypic genus Lecomtella, a rare bamboo-like endemic from Madagascar, has never been appropriately evaluated. Until now its taxonomic treatment has remained controversial, indicating the need for re-evaluation based on a combination of molecular and morphological data. Methods The phylogenetic position of Lecomtella in Poaceae was evaluated based on sequences from the nuclear and plastid genomes generated by next-generation sequencing (NGS). In addition, a detailed morphological description of L. madagascariensis was produced, and its distribution and habit were investigated in order to assess its conservation status. Key Results The complete plastid sequence, a ribosomal DNA unit and fragments of low-copy nuclear genes (phyB and ppc) were obtained. All phylogenetic analyses place Lecomtella as an isolated member of the core panicoids, which last shared a common ancestor with other species >20 million years ago. Although Lecomtella exhibits morphological characters typical of Panicoideae, an unusual combination of traits supports its treatment as a separate group. Conclusions The study showed that NGS can be used to generate abundant phylogenetic information rapidly, opening new avenues for grass phylogenetics. These data clearly showed that Lecomtella forms an isolated lineage, which, in combination with its morphological peculiarities, justifies its treatment as a separate tribe: Lecomtelleae. New descriptions of the tribe, genus and species are presented with a typification, a distribution map and an IUCN conservation assessment. PMID:23985988

Besnard, Guillaume; Christin, Pascal-Antoine; Malé, Pierre-Jean G.; Coissac, Eric; Ralimanana, Hélène; Vorontsova, Maria S.

2013-01-01

394

Epidemiology of Pathogenic Enterobacteria in Humans, Livestock, and Peridomestic Rodents in Rural Madagascar  

PubMed Central

Background Among the families of enteric bacteria are globally important diarrheal agents. Despite their potential for zoonotic and environmental transmission, few studies have examined the epidemiology of these pathogens in rural systems characterized by extensive overlap among humans, domesticated and peridomestic animals. We investigated patterns of infection with Enterotoxigenic Escherichia coli, Shigella spp., Salmonella enterica, Vibrio cholerae, and Yersinia spp. (enterocolitica, and pseudotuberculosis) in Southeastern Madagascar where the potential for the aforementioned interactions is high. In this pilot project we conducted surveys to examine behaviors potentially associated with risk of infection and if infection with specific enterobacteria species was associated with diarrheal disease. Methodology/Principal Findings PCR was conducted on DNA from human, livestock, and rodent fecal samples from three villages. Overall, human prevalence was highest (77%), followed by rodents (51%) and livestock (18%). Rodents were ?2.8 times more likely than livestock to carry one of the bacteria. The incidence of individual species varied between villages, with the observation that, E. coli and Shigella spp. were consistently associated with co-infections. As an aggregate, there was a significant risk of infection linked to a water source in one village. Individually, different pathogens were associated with certain behaviors, including: those who had used medication, experienced diarrhea in the past four weeks, or do not use toilets. Conclusions/Significance Different bacteria were associated with an elevated risk of infection for various human activities or characteristics. Certain bacteria may also predispose people to co-infections. These data suggest that a high potential for transmission among these groups, either directly or via contaminated water sources. As these bacteria were most prevalent in humans, it is possible that they are maintained in humans and that transmission to other species is infrequent. Further studies are needed to understand bacterial persistence, transmission dynamics, and associated consequences in this and similar systems. PMID:24983990

Bublitz, DeAnna C.; Wright, Patricia C.; Bodager, Jonathan R.; Rasambainarivo, Fidisoa T.; Bliska, James B.; Gillespie, Thomas R.

2014-01-01

395

Similarities, differences, and seasonal patterns in the diets of Eulemur rubriventer and Eulemur fulvus rufus in the Ranomafana National Park, Madagascar  

Microsoft Academic Search

I studied the diets of two sympatric species ofEulemur (E. fulvus rufus andE. rubriventer) in the Ranomafana National Part in southeastern Madagascar from July 1988 through August 1989. Both species were highly frugivorous throughout the year and devoted similar amounts of time to feeding daily; the composition of their diets were similar. Three aspects of both lemur species' diets were

Deborah J. Overdorff

1993-01-01

396

T H R E AT E N E D F R O G S O F MadagascarFranco Andreone, Mike Bungard & Karen Freeman  

E-print Network

into agricultural or grazing land to provide food for a growing human population and to grow crops like vanilla of Malagasy frogs. Among these, education and public awareness play an important role. This booklet, aimed and has been separated from the main- land for at least 165 million years. Because Madagascar has been

Andreone, Franco

397

Identification of priority areas for plant conservation in Madagascar using Red List criteria: rare and threatened Pandanaceae indicate sites in need of protection  

Microsoft Academic Search

A major problem in establishing effective protocols for conserving Madagascar's biodiversity is the lack of reliable information for the identification of priority sites in need of protection. Analyses of field data and information from herbarium collections for mem- bers of the plant family Pandanaceae (85 spp. of Pandanus; 6 spp. of Martellidendron) showed how risk of extinction assessments can inform

Martin W. Callmander; George E. Schatz; Porter P. Lowry II; Michel O. Laivao; Jeannie Raharimampionona; Sylvie Andriambololonera; Tantely Raminosoa; Trisha K. Consiglio

2007-01-01

398

Developpement, amenagement linguistique et terminologie: Un mythe? L'exemple de la malgachisation (Development, Language Planning, and Terminology: A Myth? The Example of Madagascar).  

ERIC Educational Resources Information Center

The French language provides a context for comparison of the modernization efforts of Quebec and Madagascar, looking at the following issues: the beginning role of the language in the society, political influences, language needs for technology transfer and the introduction of terminology in societies with well-documented and poorly-documented…

Boulanger, Jean-Claude

1989-01-01

399

"Even with Higher Education You Remain a Woman": A Gender Perspective on Higher Education and Social Change in the Toliara Region of Madagascar  

ERIC Educational Resources Information Center

This article investigates some issues related to gender and education based on a qualitative, empirical study of women in higher education in the Toliara region of Madagascar. The focus is on how women's participation in higher education has created changes in gender relations, and how these women have succeeded in achieving higher education. In…

Skjortnes, Marianne; Zachariassen, Heidi Holt

2010-01-01

400

A new tree hole breeding Anodonthyla (Chordata: Anura: Microhylidae: Cophylinae) from low-altitude rainforests of the Masoala Peninsula, northeastern Madagascar  

Microsoft Academic Search

We describe a new arboreal, cophyline, microhylid frog from the rainforest of northeastern Madagascar belonging to the genus Anodonthyla. Anodonthyla hutchisoni, new species, is named in honor of a lifetime of dedication to excellence in herpetology by V. H. Hutchison. Anodonthyla hutchisoni differs from a close relative, A. boulengeri, in having generally larger morphometric features and in aspects of pattern

Danté B. Fenolio; Mark E. Walvoord; Jim F. Stout; Jasmin E. Randrianirina; Franco Andreone

2007-01-01

401

A TAXONOMIC REVISION OF GOUANIA (RHAMNACEAE) IN MADAGASCAR AND THE OTHER ISLANDS OF THE WESTERN INDIAN OCEAN (THE COMORO AND MASCARENE ISLANDS, AND THE SEYCHELLES)1  

PubMed Central

A taxonomic revision of the genus Gouania Jacq. (Rhamnaceae) is presented for Madagascar and the other western Indian Ocean islands. Seventeen species are recognized, of which nine are described and published as new (all endemic to Madagascar): G. ambrensis Buerki, Phillipson & Callm., G. callmanderi Buerki, G. cupreifolia Buerki, Phillipson & Callm., G. cupuliflora Buerki, Phillipson & Callm., G. gautieri Buerki, Phillipson & Callm., G. perrieri Buerki, Phillipson & Callm., G. phillipsonii Buerki, G. taolagnarensis Buerki, Phillipson & Callm., and G. zebrifolia Buerki, Phillipson & Callm. Sixteen species occur in Madagascar, of which 13 are endemic and three are common to Madagascar and one or more of the smaller Indian Ocean islands. The latter include G. laxiflora Tul., a species which is also present on mainland Africa. One species, G. mauritiana Lam., is endemic to Réunion Island. We recognize two subspecies within G. scandens (Gaertn.) R. B. Drumm.: G. scandens subsp. scandens and G. scandens subsp. glandulosa (Boivin ex Tul.) Buerki, Phillipson & Callm., the latter transferred from G. glandulosa Boivin ex Tul. Past confusion about the identity of this species is discussed. Five names are lectotypified: G. aphrodes Tul., G. glandulosa [= G. scandens subsp. glandulosa], G. laxiflora, G. lineata Tul., and G. tiliifolia Lam. Both lectotype and epitype are designated for G. mauritiana. Conservation assessments are provided for all species within their primary areas of occurrence. PMID:22053117

Buerki, Sven; Phillipson, Peter B.; Callmander, Martin W.

2011-01-01

402

Competition in vitro among fungi acquired from the exoskeleton of the giant Madagascar hissing-cockroach, Gromphadorhina portentosa, and its relevance to human health  

Microsoft Academic Search

Few insects have received as much public attention as the Madagascar hissing-cockroach, Gromphadorhina portentosa, coveted by children as a household pet. Recently, this insect has been linked to allergies and asthma triggered by an antagonistic external mycoflora, and some of these molds are known to cause serious illnesses, namely Aspergillus spp., Mucor spp. and Rhizopus spp. Other cockroach species serve

Jay A. Yoder; Joshua B. Benoit; Michael R. Condon; Lawrence W. Zettler

403

Look at That!: Using Madagascar Hissing Cockroaches to Develop and Enhance the Scientific Inquiry Skill of Observation in Middle School Students  

ERIC Educational Resources Information Center

Middle school students can develop and enhance their observation skills by participating in teacher-guided scientific inquiry (NRC 1996) activities where they observe animals that tend to act in known, predictable ways. Madagascar hissing cockroaches ("Gromphadorhina portentosa") are one such animal. This article presents beginning, intermediate,…

Wagler, Ron

2011-01-01

404

Genome-wide evidence of Austronesian–Bantu admixture and cultural reversion in a hunter-gatherer group of Madagascar  

PubMed Central

Linguistic and cultural evidence suggest that Madagascar was the final point of two major dispersals of Austronesian- and Bantu-speaking populations. Today, the Mikea are described as the last-known Malagasy population reported to be still practicing a hunter-gatherer lifestyle. It is unclear, however, whether the Mikea descend from a remnant population that existed before the arrival of Austronesian and Bantu agriculturalists or whether it is only their lifestyle that separates them from the other contemporary populations of South Madagascar. To address these questions we have performed a genome-wide analysis of >700,000 SNP markers on 21 Mikea, 24 Vezo, and 24 Temoro individuals, together with 50 individuals from Bajo and Lebbo populations from Indonesia. Our analyses of these data in the context of data available from other Southeast Asian and African populations reveal that all three Malagasy populations are derived from the same admixture event involving Austronesian and Bantu sources. In contrast to the fact that most of the vocabulary of the Malagasy speakers is derived from the Barito group of the Austronesian language family, we observe that only one-third of their genetic ancestry is related to the populations of the Java-Kalimantan-Sulawesi area. Because no additional ancestry components distinctive for the Mikea were found, it is likely that they have adopted their hunter-gatherer way of life through cultural reversion, and selection signals suggest a genetic adaptation to their new lifestyle. PMID:24395773

Pierron, Denis; Razafindrazaka, Harilanto; Pagani, Luca; Ricaut, François-Xavier; Antao, Tiago; Capredon, Mélanie; Sambo, Clément; Radimilahy, Chantal; Rakotoarisoa, Jean-Aimé; Blench, Roger M.; Letellier, Thierry; Kivisild, Toomas

2014-01-01

405

How Much Variation Can One Ant Species Hold? Species Delimitation in the Crematogaster kelleri-Group in Madagascar  

PubMed Central

We investigated the species-level taxonomy of the Malagasy Crematogaster (Crematogaster) kelleri-group and an additional more distantly related species of the same subgenus. Morphological data from worker, queen and male ants, as well as genetic data from three nuclear genes (long wavelength rhodopsin, arginine kinase and carbomoylphosphate synthase) and one mitochondrial marker (cytochrome oxidase I) led to the recognition of six species. Within the C. kelleri-group, three new species are described: C. hazolava Blaimer sp. n., C. hafahafa Blaimer sp. n. and C. tavaratra Blaimer sp. n. The previously described taxa C. kelleri Forel and C. madagascariensis André are validated by our analysis. Conversely, our data suggests synonymy of C. adrepens Forel (with C. kelleri) and C. gibba Emery (with C. madagascariensis). A more distantly related and phylogenetically isolated species, C. tsisitsilo Blaimer sp. n., is further described. We report high levels of morphological and molecular variation in C. kelleri and illustrate that this variation can be explained partly by geography. Species descriptions, images, distribution maps and identification keys based on worker ants, as well as on queen and male ants where available, are presented for all six species. Our work highlights the elevated species richness of Crematogaster ants throughout Madagascar’s humid forests, especially in the far northern tip of the island, and the need to use multiple data sources to ensure clear demarcation of this diversity. PMID:23874503

Blaimer, Bonnie B.; Fisher, Brian L.

2013-01-01

406

First description of autumn migration of Sooty Falcon Falco concolor from the United Arab Emirates to Madagascar using satellite telemetry  

USGS Publications Warehouse

The movement and migration pattern of the 'Near Threatened' Sooty Falcon Falco concolor is poorly known. Sooty Falcons breed on the islands of the Arabian Gulf after arriving from their non-breeding areas that are mainly in Madagascar. In the first satellite tracking of the species we fitted a 9.5 g Argos solar powered transmitter on an adult breeding Sooty Falcon off the western coast of Abu Dhabi in the United Arab Emirates. The bird successfully undertook autumn migration to Madagascar, a known wintering area for the species. We document the Sooty Falcon's autumn migration route and stop-over sites. The adult Sooty Falcon initiated its migration at night and with tailwinds, and travelled mainly during daytime hours for 13 days over an inland route of more than 5,656 km. The three stop-over sites in East Africa were characterised by moderate to sparse shrub cover associated with potential sources of water. We discuss the migration pattern of the tracked bird in relation to importance of non-breeding areas for Sooty Falcons and recent declines in numbers in their breeding range.

Javed, Salim; Douglas, David C.; Khan, Shahid Noor; Nazeer Shah, Junid; Ali Al Hammadi, Abdullah

2012-01-01

407

Spread and strain determination of Varroa destructor (Acari: Varroidae) in Madagascar since its first report in 2010.  

PubMed

Varroa destructor is a major pest in world beekeeping. It was first detected in Madagascar in 2010 on the endemic honeybee Apis mellifera unicolor. To evaluate V. destructor spread dynamics in Madagascar a global survey was conducted in 2011-2012. A total of 695 colonies from 30 districts were inspected for the presence of mites. 2 years after its introduction, nine districts were found infested. Varroa destructor spread was relatively slow compared to other countries with a maximum progression of 40 km per year, the five newly infested districts being located next to the first infested ones. The incidence of mite infestation was also investigated by monitoring 73 colonies from five apiaries during 1 year (2011-2012). Sixty percent of local colony mortality was recorded after 1 year of survey. Varroa destructor strain determination was done by partial sequencing of the cytochrome oxidase I gene of 13 phoretic mites sampled in five districts. A single V. destructor mitochondrial haplotype was detected, the Korean type, also present in the closest African countries. A global pathogen survey was also conducted on the colonies inspected for mite presence. The greater wax moth, Galleria mellonella has been found in all colonies all over the country. Two other pathogens and morphological abnormalities in workers, such as deformed wings, were found associated with only V. destructor presence. A prevention management plan must be implemented to delimit mite spread across the island. PMID:23325416

Rasolofoarivao, Henriette; Clémencet, Johanna; Ravaomanarivo, Lala Harivelo Raveloson; Razafindrazaka, Dimby; Reynaud, Bernard; Delatte, Hélène

2013-08-01

408

Assessment of interactions between African swine fever virus, bushpigs (Potamochoerus larvatus), Ornithodoros ticks and domestic pigs in north-western Madagascar.  

PubMed

Since its introduction in Madagascar in 1998, African swine fever (ASF) has severely affected national pig production and persists as a common disease in that country. Two of its natural hosts in the African continent, the bushpig (Potamochoerus larvatus) and tick vectors of the Ornithodoros moubata complex, are reported in west and central regions of the island. However, their role in the maintenance and transmission of the virus has been insufficiently studied. In this work, we tried to assess their potential role in the epidemiology of the disease in Madagascar, by assessing the levels of interaction between (i) ASF virus (ASFV) and bushpigs and (ii) between soft ticks and domestic and wild suids in north-western Madagascar. Twenty-seven sera and 35 tissue samples from bushpigs were collected and analysed for the presence of anti-ASF antibodies and viral DNA. In addition, the sera from 27 bushpigs and 126 domestic pigs were analysed with an ELISA test for the detection of antibodies against salivary antigens from Ornithodoros ticks. No circulation of ASFV or anti-ASFV antibodies nor anti-tick antibodies were detected in bushpigs. However, seven of the domestic pig sera (5.6% of the total sample population) were antibody positive for O. moubata antigens. The probability of freedom from ASFV in the bushpig population using Bayesian statistical methods ranged between 73% and 84%. The probabilities of absence of anti-tick antibodies in domestic and wild pigs were estimated at 63% and 71%, respectively. These preliminary results suggest that bushpigs are unlikely to play a significant role in the maintenance and transmission of ASFV in Madagascar. Nevertheless, further ASFV surveys are needed on that species to confirm this assumption. In addition, the presence of antibodies against O. moubata in domestic pigs suggests that soft ticks may be able to maintain ASFV within a domestic pig cycle in areas of Madagascar where they remain present. PMID:21320295

Ravaomanana, J; Jori, F; Vial, L; Pérez-Sánchez, R; Blanco, E; Michaud, V; Roger, F

2011-06-01

409

Ethnobotanical and economic value of Ravenala madagascariensis Sonn. in Eastern Madagascar  

PubMed Central

Background Known worldwide as the “traveler’s tree”, the Malagasy endemic species Ravenala madagascariensis Sonn. (Strelitziaceae) is considered as an iconic symbol of Madagascar. It is a widespread species in the eastern part of the country with four different varieties which are well represented in Ambalabe community. All of them are used for different purposes and the species represents an important cultural value in the lives of the local population. However, uses of Ravenala are only generally well known by local population. Thus, in this study, we report on the different uses of Ravenala and its importance to the Ambalabe local people. Methods Semi-structured interviews among 116 people, 59 men and 57 women with ages ranging from 17 to 84 years old, free listing and market surveys were conducted in order to collect the vernacular names, the uses of Ravenala madagascariensis and the price of plant parts sold in local market. Then, the uses were categorized according to Cámara-Leret et al. classification. Results Different parts of the plant are currently used by local population, which are grouped as heart, trunk, leaves, petioles and rachis. Seven categories of use were recorded, most cited include: human food, utensils and tools, and house building. The most commonly used parts are trunk, heart, leaves and petioles for which the price varies between $3-15. Uses mentioned for construction (floor, roofs and wall), human food and utensils and tools are the most frequent and salient for local population. But the use of the plant as first materials for house building is revealed to be the most important for them. Conclusions Ravenala madagascariensis is very important to the Ambalabe communities because for local population, it represents the Betsimisaraka cultural and traditional use of the plant for house building. Moreover, none of its parts are discarded. The harvest and sale of R. madagascariensis for building materials can also provide an additional source of income to the family. Besides, using Ravenala in house construction reduces the use of slow growing trees and contributes to the sustainable use of natural forest resources. PMID:25027625

2014-01-01

410

Results of a randomised trial of male condom promotion among Madagascar sex workers  

PubMed Central

Objectives: To test the effect of supplementing peer promotion of male condom use with clinic based counselling, measured in terms of STI prevalence and reported male condom use. Methods: 1000 female sex workers in Madagascar were randomised to two study arms: peer education supplemented by individual risk reduction counselling by a clinician (peer + clinic) versus condom promotion by peer educators only (peer only). STI testing was conducted at baseline and 6 months. Behavioural interviews were administered at baseline, 2, 4, and 6 months. Results: At baseline, women in the peer only arm had prevalences of 16.0%, 23.6%, and 12.1% for chlamydia, gonorrhoea, and trichomoniasis respectively, with an aggregate prevalence of 38.2%. Baseline STI prevalences for the peer + clinic arm were slightly lower and 34.1% in aggregate. At 6 months, aggregate STI prevalence increased in the peer only arm to 41.4%, whereas the aggregate prevalence diminished slightly to 32.1% in the peer + clinic arm. In logistic regression analyses, the estimated odds ratios (ORs) for chlamydia, gonorrhoea, trichomoniasis, and aggregate STI were 0.7 (95% confidence interval 0.4 to 1.0), 0.7 (0.5 to 1.0), 0.8 (0.6 to 1.2), and 0.7 (0.5 to 0.9) respectively, comparing the peer + clinic arm with the peer only arm. The logistic regression OR for reported condom use with clients in the past 30 days increased from 1.1 at 2 months to 1.8 at 6 months, comparing the peer + clinic arm with the peer only arm, and was 1.4 overall (1.1 to 1.8). Adjustment for baseline factors changed the regression results little. Conclusions: The impact of male condom promotion on behaviour can be heightened through more concentrated counselling on risk reduction. Persistently high STI prevalence despite increases in reported condom use by sex workers supports the need for multidimensional control programmes. PMID:15800098

Feldblum, P; Hatzell, T; Van Damme, K; Nasution, M; Rasamindrakotroka, A; Grey, T

2005-01-01

411

Entomological and parasitological impacts of indoor residual spraying with DDT, alphacypermethrin and deltamethrin in the western foothill area of Madagascar  

PubMed Central

Background In Madagascar, indoor residual spraying (IRS) with insecticide was part of the national malaria control programme since the middle of the twentieth century. It was mainly employed in the highlands and the foothill areas, which are prone to malaria epidemics. Prior to a policy change foreseeing a shift from DDT to pyrethroids, a study was carried out to assess the entomological and parasitological impacts of IRS in areas with DDT or pyrethroids and in areas without IRS. Methods The study was carried out from October 2002 to February 2005 in three communes of the western foothill area of Madagascar. Two communes received IRS with DDT in February 2003, then IRS with pyrethroids (alphacypermethrin or deltamethrin) in February 2004. The third commune remained untreated. Mosquitoes were collected at night using human landing catches and early in the morning in resting places. Blood smears were obtained from schoolchildren and microscopically examined for Plasmodium presence. Results In total, 18,168 human landing mosquitoes and 12,932 resting anophelines were collected. The Anopheles species caught comprised 10 species. The main and most abundant malaria vector was Anopheles funestus (72.3% of human-seeking malaria vectors caught indoors). After IRS had taken place, this species exhibited a lower human biting rate and a lower sporozoite index. Overall, 5,174 blood smears were examined with a mean plasmodic index of 19.9%. A total of four Plasmodium species were detected. Amongst tested school children the highest plasmodial index was 54.6% in the untreated commune, compared to 19.9% in the commune sprayed with DDT and 11.9% in the commune sprayed with pyrethroid. The highest prevalence of clinical malaria attacks in children present at school the day of the survey was 33% in the untreated commune compared to 8% in the areas which received IRS. Conclusion In terms of public health, the present study shows (1) a high efficacy of IRS with insecticide, (2) a similar efficacy of DDT and pyrethroid and (3) a similar efficacy of alphacypermethrin and deltamethrin. The use of IRS with DDT and pyrethroid greatly decreased the vector-human contact, with an associated decrease of the plasmodial index. However malaria transmission did not reach zero, probably due to the exophilic host-seeking and resting behaviours of the malaria vectors, thus avoiding contact with insecticide-treated surfaces indoors. The study highlights the strengths and weaknesses of the IRS implementation and the need for complementary tools for an optimal vector control in Madagascar. PMID:24423246

2014-01-01

412

Chloroquine Clinical Failures in P. falciparum Malaria Are Associated with Mutant Pfmdr-1, Not Pfcrt in Madagascar  

PubMed Central

Molecular studies have demonstrated that mutations in the Plasmodium falciparum chloroquine resistance transporter gene (Pfcrt) play a major role in chloroquine resistance, while mutations in P. falciparum multidrug resistance gene (Pfmdr-1) act as modulator. In Madagascar, the high rate of chloroquine treatment failure (44%) appears disconnected from the overall level of in vitro CQ susceptibility (prevalence of CQ-resistant parasites <5%) or Pfcrt mutant isolates (<1%), strongly contrasting with sub-Saharan African countries. Previous studies showed a high frequency of Pfmdr-1 mutant parasites (>60% of isolates), but did not explore their association with P. falciparum chloroquine resistance. To document the association of Pfmdr-1 alleles with chloroquine resistance in Madagascar, 249 P. falciparum samples collected from patients enrolled in a chloroquine in vivo efficacy study were genotyped in Pfcrt/Pfmdr-1 genes as well as the estimation of the Pfmdr-1 copy number. Except 2 isolates, all samples displayed a wild-type Pfcrt allele without Pfmdr-1 amplification. Chloroquine treatment failures were significantly associated with Pfmdr-1 86Y mutant codon (OR?=?4.6). The cumulative incidence of recurrence of patients carrying the Pfmdr-1 86Y mutation at day 0 (21 days) was shorter than patients carrying Pfmdr-1 86N wild type codon (28 days). In an independent set of 90 selected isolates, in vitro susceptibility to chloroquine was not associated with Pfmdr-1 polymorphisms. Analysis of two microsatellites flanking Pfmdr-1 allele showed that mutations occurred on multiple genetic backgrounds. In Madagascar, Pfmdr-1 polymorphism is associated with late chloroquine clinical failures and unrelated with in vitro susceptibility or Pfcrt genotype. These results highlight the limits of the current in vitro tests routinely used to monitor CQ drug resistance in this unique context. Gaining insight about the mechanisms that regulate polymorphism in Pfmdr1 remains important, particularly regarding the evolution and spread of Pfmdr-1 alleles in P. falciparum populations under changing drug pressure which may have important consequences in terms of antimalarial use management. PMID:20967251

Andriantsoanirina, Valérie; Ratsimbasoa, Arsène; Bouchier, Christiane; Tichit, Magali; Jahevitra, Martial; Rabearimanana, Stéphane; Raherinjafy, Rogelin; Mercereau-Puijalon, Odile; Durand, Rémy; Ménard, Didier

2010-01-01

413

A Fatal Neuroinvasive West Nile Virus Infection in a Traveler Returning from Madagascar: Clinical, Epidemiological and Veterinary Investigations  

PubMed Central

A 58-year-old woman living in Reunion Island and returning from Madagascar was hospitalized for neuroinvasive encephalitis and died 1 month later. West Nile virus (WNV) infection was biologically confirmed by detection of immunoglobulin M (IgM) reactive with WNV antigens in both cerebrospinal fluid and serum, and weak neutralizing activity was also detected. A veterinary survey performed in her traveling area showed a seroprevalence of WNV of 28.7% (95% confidence interval [CI] = 21.1–36.3) in adult poultry, confirming an active circulation of the virus. Development of a severe form could be related to a weak antibody response, because the patient presented low IgM and IgG titers. This case report underlines the constant risk of emergence of West Nile in Indian Ocean territories, including Reunion Island where competent vectors are widely present during the whole year. PMID:23751400

Larrieu, Sophie; Cardinale, Eric; Ocquidant, Philippe; Roger, Matthieu; Lepec, Richard; Delatte, Hélène; Camuset, Guillaume; Desprès, Philippe; Brottet, Elise; Charlin, Cyril; Michault, Alain

2013-01-01

414

Isolation of a non-haemadsorbing, non-cytopathic strain of African swine fever virus in Madagascar.  

PubMed Central

African swine fever (ASF) suspected clinically in Madagascar (1998-9) was confirmed by polymerase chain reaction (PCR) and nucleotide sequencing, following virus isolation. No haemadsorption or cytopathic effect could be detected following leukocyte inoculation, but viral growth in cells was confirmed by PCR. Detection of ASF virus genome was carried out by amplification of a highly conserved region coding for the p72 protein. Nucleotide sequencing of the amplicon revealed 99.2% nucleotide identity between the recent Malagasy strains and a virus recovered from the 1994 outbreak in Mozambique (SPEC265). A serological survey performed on 449 sera, revealed that only 5.3% of the sera taken from pigs between 1998 and 1999 were positive. PMID:11467803

Gonzague, M.; Roger, F.; Bastos, A.; Burger, C.; Randriamparany, T.; Smondack, S.; Cruciere, C.

2001-01-01

415

Bringing safe water to remote populations: an evaluation of a portable point-of-use intervention in rural Madagascar.  

PubMed

Rural populations disproportionately lack access to improved water supplies. We evaluated a novel scheme that employed community-based sales agents to disseminate the Safe Water System (SWS)--a household-level water chlorination and safe storage intervention--in rural Madagascar. Respondents from 242 households in 4 villages were interviewed; all used surface water for drinking water. Respondents from 239 households (99%) had heard of Sûr'Eau, the SWS disinfectant; 226 (95%) reported having ever used Sûr'Eau, and 166 (73%) reported current use. Current Sûr'Eau use was confirmed in 54% of households. Community sales agents effectively motivated their neighbors to adopt a new health behavior that prevents diarrhea. Future work should focus on strategies for sustaining SWS use, factors that motivate community-based sales agents to promote SWS, and the feasibility of scaling up this approach. PMID:17267727

Ram, Pavani Kalluri; Kelsey, Elaine; Rasoatiana; Miarintsoa, Rabeantoandro Rado; Rakotomalala, Oliver; Dunston, Chris; Quick, Robert E

2007-03-01

416

Late Quaternary history of the Vakinankaratra volcanic field (central Madagascar): insights from luminescence dating of phreatomagmatic eruption deposits  

NASA Astrophysics Data System (ADS)

The Quaternary Vakinankaratra volcanic field in the central Madagascar highlands consists of scoria cones, lava flows, tuff rings, and maars. These volcanic landforms are the result of processes triggered by intracontinental rifting and overlie Precambrian basement or Neogene volcanic rocks. Infrared-stimulated luminescence (IRSL) dating was applied to 13 samples taken from phreatomagmatic eruption deposits in the Antsirabe-Betafo region with the aim of constraining the chronology of the volcanic activity. Establishing such a chronology is important for evaluating volcanic hazards in this densely populated area. Stratigraphic correlations of eruption deposits and IRSL ages suggest at least five phreatomagmatic eruption events in Late Pleistocene times. In the Lake Andraikiba region, two such eruption layers can be clearly distinguished. The older one yields ages between 109 ± 15 and 90 ± 11 ka and is possibly related to an eruption at the Amboniloha volcanic complex to the north. The younger one gives ages between 58 ± 4 and 47 ± 7 ka and is clearly related to the phreatomagmatic eruption that formed Lake Andraikiba. IRSL ages of a similar eruption deposit directly overlying basement laterite in the vicinity of the Fizinana and Ampasamihaiky volcanic complexes yield coherent ages of 68 ± 7 and 65 ± 8 ka. These ages provide the upper age limit for the subsequently developed Iavoko, Antsifotra, and Fizinana scoria cones and their associated lava flows. Two phreatomagmatic deposits, identified near Lake Tritrivakely, yield the youngest IRSL ages in the region, with respective ages of 32 ± 3 and 19 ± 2 ka. The reported K-feldspar IRSL ages are the first recorded numerical ages of phreatomagmatic eruption deposits in Madagascar, and our results confirm the huge potential of this dating approach for reconstructing the volcanic activity of Late Pleistocene to Holocene volcanic provinces.

Rufer, Daniel; Preusser, Frank; Schreurs, Guido; Gnos, Edwin; Berger, Alfons

2014-05-01

417

Rivaling the World's Smallest Reptiles: Discovery of Miniaturized and Microendemic New Species of Leaf Chameleons (Brookesia) from Northern Madagascar  

PubMed Central

Background One clade of Malagasy leaf chameleons, the Brookesia minima group, is known to contain species that rank among the smallest amniotes in the world. We report on a previously unrecognized radiation of these miniaturized lizards comprising four new species described herein. Methodology/Principal Findings The newly discovered species appear to be restricted to single, mostly karstic, localities in extreme northern Madagascar: Brookesia confidens sp. n. from Ankarana, B. desperata sp. n. from Forêt d'Ambre, B. micra sp. n. from the islet Nosy Hara, and B. tristis sp. n. from Montagne des Français. Molecular phylogenetic analyses based on one mitochondrial and two nuclear genes of all nominal species in the B. minima group congruently support that the four new species, together with B. tuberculata from Montagne d'Ambre in northern Madagascar, form a strongly supported clade. This suggests that these species have diversified in geographical proximity in this small area. All species of the B. minima group, including the four newly described ones, are characterized by very deep genetic divergences of 18–32% in the ND2 gene and >6% in the 16S rRNA gene. Despite superficial similarities among all species of this group, their status as separate evolutionary lineages is also supported by moderate to strong differences in external morphology, and by clear differences in hemipenis structure. Conclusion/Significance The newly discovered dwarf chameleon species represent striking cases of miniaturization and microendemism and suggest the possibility of a range size-body size relationship in Malagasy reptiles. The newly described Brookesia micra reaches a maximum snout-vent length in males of 16 mm, and its total length in both sexes is less than 30 mm, ranking it among the smallest amniote vertebrates in the world. With a distribution limited to a very small islet, this species may represent an extreme case of island dwarfism. PMID:22348069

Glaw, Frank; Köhler, Jörn; Townsend, Ted M.; Vences, Miguel

2012-01-01

418

Preliminary study of a radiological survey in an abandoned uranium mining area in Madagascar  

NASA Astrophysics Data System (ADS)

The region of Vinaninkarena located in central Madagascar (47°02'40"E, 19°57'17"S), is known to be a high natural radioactive area. Uranium ore was extracted in this region during the 1950s and the early 1960s. In the mid-1960s, mining activities were stopped and the site abandoned. In the meantime, the region, which used to be without any inhabitants, has recently been occupied by new settlers with presumed increase in exposure of the local population to natural ionizing radiation. In order to assess radiological risk, a survey to assess the soil natural radioactivity background was conducted during the year 2004. This study was implemented in the frame of the FADES Project SP99v1b_21 entitled: Assessment of the environmental pollution by multidisciplinary approach, and the International Atomic Energy Agency Technical Cooperation Project MAG 7002 entitled: Effects of air and water pollution on human health. Global Positioning System (GPS) was used to determine the geographical coordinates of the top soil samples (0-15cm) collected. The sampling was performed using a multi integrated scale approach to estimate the spatial variability of the parameters under investigation (U, Th and K) using geo-statistical approach. A total of 205 soil samples was collected in the study site (16 km2). After humidity correction, the samples were sealed in 100 cm3 cylindrical air-tight plastic containers and stored for more than 6 months to reach a secular equilibrium between parents and short-lived progeny (226Ra and progeny, 238U and 234Th). Measurements were performed using a high-resolution HPGe Gamma-detector with a 30% relative efficiency and an energy resolution of 1.8 keV at 1332.5 keV, allowing the determination of the uranium and thorium series and 40K. In case of secular equilibrium, a non-gamma-emitting radionuclide activity was deduced from its gamma emitting progeny. This was the case for 238U (from 234Th), 226Ra (from 214Pb and 214Bi) and 232Th (from 228Ac, 212Pb or 208Tl). Furthermore, in order to assess the radiological effect, the kerma rate in the air at 1 m above ground level was calculated for each sampled points using standard activity-kerma rate conversion coefficients for uranium, thorium series and potassium. Geostatistical interpolation tools (e.g. Inverse Distance Weighting power 2 and Ordinary Kriging) were used to optimize the data set mapping. The measured Potassium-40 activity was 333 Bq kg-1 ± 95% (Mean ± Coefficient of Variation), the Uranium activity was 195 Bq kg-1 ± 53% and the Thorium activity was 139 Bq kg-1 ± 29%. The world average concentrations are reported by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) as 400 Bq kg-1 for 40K, 35 Bq kg-1 for 238U and 30 Bq kg-1 for 232Th. The results show that generally, 40K concentrations in soils of the area are slightly lower than the world average value, whereas uranium and thorium series activities are noticeably higher. On average the kerma rate reaches 143 nGy h-1 with a standard deviation of 41 nGy h-1 and a coefficient of variation of 28%. The information obtained was mapped and the dose exposition was also assessed for the local settlers. Key-words: soil contamination, environmental radioactivity, radioecology, dose exposure.

N, Rabesiranana; M, Rasolonirina; F, Solonjara A.; Andriambololona., Raoelina; L, Mabit

2010-05-01

419

A new species of the Boophis rappiodes group (Anura, Mantellidae) from the Sahamalaza Peninsula, northwest Madagascar, with acoustic monitoring of its nocturnal calling activity  

PubMed Central

Abstract A new species of treefrog of the Boophis rappiodes group (Anura, Mantellidae) is described from the Sahamalaza – Iles Radama National Park in northwest Madagascar. This new species is green in colour with bright red speckling across its head and dorsum; similar in morphology to other species of this group including: B. bottae, B. rappiodes, B. erythrodactylus and B. tasymena. The new species can be distinguished by its advertisement call and by a genetic divergence of more than 4.9% in the analysed mitochondrial 16S rRNA gene fragment. Its call consists of two note types: a trill and a click; although similar sounding to B. bottae, the trill note of the new species has a faster pulse rate while the click note is predominantly two-pulsed rather than three. All individuals were detected from the banks of two streams in Ankarafa Forest. The new species represents the only member of the B. rappiodes group endemic to Madagascar’s western coast, with the majority of other members known from the eastern rainforest belt. Despite its conspicuous call, it has not been detected from other surveys of northwest Madagascar and it is likely to be a local endemic to the peninsula. The ranges of two other amphibian species also appear restricted to Sahamalaza, and so the area seems to support a high level of endemicity. Although occurring inside a National Park, this species is highly threatened by the continuing decline in the quality and extent of its habitat. Due to these threats it is proposed that this species should be classified as Critically Endangered according to the IUCN Red List criteria. PMID:25152689

Penny, Samuel G.; Andreone, Franco; Crottini, Angelica; Holderied, Marc W.; Rakotozafy, Lovasoa Sylviane; Schwitzer, Christoph; Rosa, Gonçalo M.

2014-01-01

420

A revision of the genus Herminella Spaeth (Chrysomelidae: Cassidinae: Notosacanthini), with a description of a new related genus and species from Madagascar.  

PubMed

The genus Herminella Spaeth from southern Africa is revised. It comprises four species: Herminella liliputana Spaeth and H. marshalli Spaeth are redescribed and two species are described as new-H. quadrimaculata from South Africa and H. flavocostata from Nambia and South Africa. A new related genus and species Hermosacantha madagascarica from Madagascar is described. Members of both genera belong to the smallest world cassids. PMID:25543568

Borowiec, Lech; Wietojañska, Jolanta

2014-01-01

421

Regulation of the external mycoflora of the giant Madagascar hissing-cockroach, gromphadorhina portentosa , by its mite associate, gromphadorholaelaps schaeferi , and its implications on human health  

Microsoft Academic Search

The giant Madagascar hissing-cockroach,Gromphadorhina portentosa, and its mite associate,Gromphadorholaelaps schaeferi, constitute an intimate commensalistic symbiosis. While the mite’s very survival is dependent by feeding on cockroach saliva\\u000a and associated organic debris, the degree that the cockroach benefits from this association is unclear. We investigated the\\u000a mite’s potential role at regulating surface fungi on the exoskeletons of this insect. Numbers of

Jay A. Yoder; Michael J. Chambers; Michael R. Condon; Joshua B. Benoit; Lawrence W. Zettler

2009-01-01

422

Role of permanent host association with the Madagascar hissing-cockroach, Gromphadorhina portentosa , on the developmental water requirements of the mite, Gromphadorholaelaps schaeferi  

Microsoft Academic Search

We provide the first complete description of the water requirements for the hissing-cockroach mite, Gromphadorholaelaps\\u000a schaeferi, focusing on characteristics that result from the restriction of all stages to the Madagascar hissing-cockroach (Gromphadorhina\\u000a portentosa). Particularly, we determine how G. schaeferi spends its entire life on the same individual cockroach. This mite is not parasitic, rather they feed on cockroach saliva\\u000a and

J. A. Yoder; B. Z. Hedges; J. B. Benoit; G. D. Keeney

2009-01-01

423

The Karnataka Late Cretaceous Dykes as products of the Marion Hot Spot at the Madagascar - India Breakup Event: Evidence from 40Ar-39Ar geochronology and geochemistry  

NASA Astrophysics Data System (ADS)

Two late Cretaceous mafic dykes with an ENE strike that is orthogonal to the west coast of India and located nearly 200 km inland around Huliyardurga, Karnataka state, yield 40Ar-39Ar plateau ages of 90.0±1.0 and 87.5±0.9 Ma. These Fe-Ti-enriched tholeiites are essentially co-eval with at least four other igneous suites widely scattered in southern India, namely; the south and north Kerala dykes, the Agali-Anaikatti dykes of central Kerala-Tamil Nadu and lavas of St Mary islands off the west coast of India. The Karnataka Cretaceous dykes are also co-eval and compositionally very similar to the Fe-Ti-enriched tholeiitic lavas and dykes around Mananjary, a major phase of Late Cretaceous magmatism along the eastern rifted margin of Madagascar which are believed to be products of the Marion hot spot that extruded at ?88 Ma, synchronous with the India-Madagascar break up eve