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Sample records for adult zebra finch

  1. Observing the Zebra Finch.

    ERIC Educational Resources Information Center

    Waters, Charles

    1979-01-01

    Presents natural history information on the zebra finch (Taeniopygia castanotis) for the biology teacher. Includes a section on care of the birds in the classroom and a method for constructing an inexpensive cage. (SA)

  2. Song decrystallization in adult zebra finches does not require the song nucleus NIf.

    PubMed

    Roy, Arani; Mooney, Richard

    2009-08-01

    In adult male zebra finches, transecting the vocal nerve causes previously stable (i.e., crystallized) song to slowly degrade, presumably because of the resulting distortion in auditory feedback. How and where distorted feedback interacts with song motor networks to induce this process of song decrystallization remains unknown. The song premotor nucleus HVC is a potential site where auditory feedback signals could interact with song motor commands. Although the forebrain nucleus interface of the nidopallium (NIf) appears to be the primary auditory input to HVC, NIf lesions made in adult zebra finches do not trigger song decrystallization. One possibility is that NIf lesions do not interfere with song maintenance, but do compromise the adult zebra finch's ability to express renewed vocal plasticity in response to feedback perturbations. To test this idea, we bilaterally lesioned NIf and then transected the vocal nerve in adult male zebra finches. We found that bilateral NIf lesions did not prevent nerve section-induced song decrystallization. To test the extent to which the NIf lesions disrupted auditory processing in the song system, we made in vivo extracellular recordings in HVC and a downstream anterior forebrain pathway (AFP) in NIf-lesioned birds. We found strong and selective auditory responses to the playback of the birds' own song persisted in HVC and the AFP following NIf lesions. These findings suggest that auditory inputs to the song system other than NIf, such as the caudal mesopallium, could act as a source of auditory feedback signals to the song motor network.

  3. The effects of delayed auditory feedback revealed by bone conduction microphone in adult zebra finches

    PubMed Central

    Fukushima, Makoto; Margoliash, Daniel

    2015-01-01

    Vocal control and learning are critically dependent on auditory feedback in songbirds and humans. Continuous delayed auditory feedback (cDAF) robustly disrupts speech fluency in normal humans and has ameliorative effects in some stutterers; however, evaluations of the effects of cDAF on songbirds are rare. We exposed singing young (141–151 days old) adult zebra finch males to high-amplitude cDAF. cDAF exposure was achieved by the recording of bone-conducted sounds using a piezoelectric accelerometer, which resulted in high-quality song recordings that were relatively uncontaminated by airborne sounds. Under this condition of cDAF, birds rapidly (2–6 days) changed their song syllable timing. The one bird for which we were able to maintain the accelerometer recordings over a long period of time recovered slowly over more than a month after cDAF was discontinued. These results demonstrate that cDAF can cause substantial changes in the motor program for syllable timing generation over short intervals of time in adult zebra finches. PMID:25739659

  4. The effects of delayed auditory feedback revealed by bone conduction microphone in adult zebra finches.

    PubMed

    Fukushima, Makoto; Margoliash, Daniel

    2015-01-01

    Vocal control and learning are critically dependent on auditory feedback in songbirds and humans. Continuous delayed auditory feedback (cDAF) robustly disrupts speech fluency in normal humans and has ameliorative effects in some stutterers; however, evaluations of the effects of cDAF on songbirds are rare. We exposed singing young (141-151 days old) adult zebra finch males to high-amplitude cDAF. cDAF exposure was achieved by the recording of bone-conducted sounds using a piezoelectric accelerometer, which resulted in high-quality song recordings that were relatively uncontaminated by airborne sounds. Under this condition of cDAF, birds rapidly (2-6 days) changed their song syllable timing. The one bird for which we were able to maintain the accelerometer recordings over a long period of time recovered slowly over more than a month after cDAF was discontinued. These results demonstrate that cDAF can cause substantial changes in the motor program for syllable timing generation over short intervals of time in adult zebra finches. PMID:25739659

  5. Dynamics of zebra finch and mockingbird vocalizations

    NASA Astrophysics Data System (ADS)

    Cimenser, Aylin

    such dynamics. Our Zebra Finch data consist of continuous recordings of six tutored birds from the early, plastic stages of sound production to the development of fully crystallized mature song. Our analysis reveals that well before the Zebra Finch hears adult song, identifiably distinct clusters are observable for all birds in the same regions of feature space. (Abstract shortened by UMI.)

  6. Carbachol-Induced Reduction in the Activity of Adult Male Zebra Finch RA Projection Neurons.

    PubMed

    Meng, Wei; Wang, Song-Hua; Li, Dong-Feng

    2016-01-01

    Cholinergic mechanism is involved in motor behavior. In songbirds, the robust nucleus of the arcopallium (RA) is a song premotor nucleus in the pallium and receives cholinergic inputs from the basal forebrain. The activity of projection neurons in RA determines song motor behavior. Although many evidences suggest that cholinergic system is implicated in song production, the cholinergic modulation of RA is not clear until now. In the present study, the electrophysiological effects of carbachol, a nonselective cholinergic receptor agonist, were investigated on the RA projection neurons of adult male zebra finches through whole-cell patch-clamp techniques in vitro. Our results show that carbachol produced a significant decrease in the spontaneous and evoked action potential (AP) firing frequency of RA projection neurons, accompanying a hyperpolarization of the membrane potential, an increase in the evoked AP latency, afterhyperpolarization (AHP) peak amplitude, and AHP time to peak, and a decrease in the membrane input resistance, membrane time constant, and membrane capacitance. These results indicate that carbachol reduces the activity of RA projection neurons by hyperpolarizing the resting membrane potential and increasing the AHP and the membrane conductance, suggesting that the cholinergic modulation of RA may play an important role in song production. PMID:26904300

  7. Effects of early developmental conditions on innate immunity are only evident under favourable adult conditions in zebra finches.

    PubMed

    De Coster, Greet; Verhulst, Simon; Koetsier, Egbert; De Neve, Liesbeth; Briga, Michael; Lens, Luc

    2011-12-01

    Long-term effects of unfavourable conditions during development can be expected to depend on the quality of the environment experienced by the same individuals during adulthood. Yet, in the majority of studies, long-term effects of early developmental conditions have been assessed under favourable adult conditions only. The immune system might be particularly vulnerable to early environmental conditions as its development, maintenance and use are thought to be energetically costly. Here, we studied the interactive effects of favourable and unfavourable conditions during nestling and adult stages on innate immunity (lysis and agglutination scores) of captive male and female zebra finches (Taeniopygia guttata). Nestling environmental conditions were manipulated by a brood size experiment, while a foraging cost treatment was imposed on the same individuals during adulthood. This combined treatment showed that innate immunity of adult zebra finches is affected by their early developmental conditions and varies between both sexes. Lysis scores, but not agglutination scores, were higher in individuals raised in small broods and in males. However, these effects were only present in birds that experienced low foraging costs. This study shows that the quality of the adult environment may shape the long-term consequences of early developmental conditions on innate immunity, as long-term effects of nestling environment were only evident under favourable adult conditions.

  8. Effects of early developmental conditions on innate immunity are only evident under favourable adult conditions in zebra finches

    NASA Astrophysics Data System (ADS)

    de Coster, Greet; Verhulst, Simon; Koetsier, Egbert; de Neve, Liesbeth; Briga, Michael; Lens, Luc

    2011-12-01

    Long-term effects of unfavourable conditions during development can be expected to depend on the quality of the environment experienced by the same individuals during adulthood. Yet, in the majority of studies, long-term effects of early developmental conditions have been assessed under favourable adult conditions only. The immune system might be particularly vulnerable to early environmental conditions as its development, maintenance and use are thought to be energetically costly. Here, we studied the interactive effects of favourable and unfavourable conditions during nestling and adult stages on innate immunity (lysis and agglutination scores) of captive male and female zebra finches ( Taeniopygia guttata). Nestling environmental conditions were manipulated by a brood size experiment, while a foraging cost treatment was imposed on the same individuals during adulthood. This combined treatment showed that innate immunity of adult zebra finches is affected by their early developmental conditions and varies between both sexes. Lysis scores, but not agglutination scores, were higher in individuals raised in small broods and in males. However, these effects were only present in birds that experienced low foraging costs. This study shows that the quality of the adult environment may shape the long-term consequences of early developmental conditions on innate immunity, as long-term effects of nestling environment were only evident under favourable adult conditions.

  9. Smooth Operator: Avoidance of Subharmonic Bifurcations through Mechanical Mechanisms Simplifies Song Motor Control in Adult Zebra Finches

    PubMed Central

    Elemans, Coen P. H.; Laje, Rodrigo; Mindlin, Gabriel B.; Goller, Franz

    2012-01-01

    Like human infants, songbirds acquire their song by imitation and eventually generate sounds that result from complicated neural networks and intrinsically nonlinear physical processes. Signatures of low-dimensional chaos such as subharmonic bifurcations have been reported in adult and developing zebra finch song. Here, we use methods from nonlinear dynamics to test whether adult male zebra finches (Taenopygia guttata) use the intrinsic nonlinear properties of their vocal organ, the syrinx, to insert subharmonic transitions in their song. In contrast to previous data on the basis of spectrographic evidence, we show that subharmonic transitions do not occur in adult song. Subharmonic transitions also do not arise in artificially induced sound in the intact syrinx, but are commonly generated in the excised syrinx. These findings suggest that subharmonic transitions are not used to increase song complexity, and that the brain controls song in a surprisingly smooth control regimen. Fast, smooth changes in acoustic elements can be produced by direct motor control in a stereotyped fashion, which is a more reliable indicator of male fitness than abrupt acoustic changes that do not require similarly precise control. Consistent with this view is the presence of high fidelity at every level of motor control, from telencephalic premotor areas to superfast syringeal muscles. PMID:20926650

  10. Development and adult phase plasticity of syllable repetitions in the birdsong of captive zebra finches (Taeniopygia guttata).

    PubMed

    Helekar, S A; Espino, G G; Botas, A; Rosenfield, D B

    2003-10-01

    Oscines learn their birdsongs from tutors. The authors found that a small fraction (approximately 7%) of captive male zebra finches (Taeniopygia guttata) produce variant acoustic birdsong profiles consisting of repetitions of single song syllables at high frequencies. Juvenile offspring of nonrepeaters can selectively learn the syntactic rule or habit of repeating syllables from repeaters. Adult tutored syllable repeaters, unlike spontaneous repeaters, undergo a form of song plasticity involving progressive reduction of the mean number and variance of repeated syllables as a function of long-term exposure to nonrepeater songs without altering the number or sequence of syllables within motifs. These findings suggest that aspects of song syntax or temporal frame can be acquired independently of song syllable or spectral content, and plasticity involving restorative alteration of acquired variant temporal frames can occur after the closure of the critical period for song learning.

  11. Development and adult phase plasticity of syllable repetitions in the birdsong of captive zebra finches (Taeniopygia guttata).

    PubMed

    Helekar, S A; Espino, G G; Botas, A; Rosenfield, D B

    2003-10-01

    Oscines learn their birdsongs from tutors. The authors found that a small fraction (approximately 7%) of captive male zebra finches (Taeniopygia guttata) produce variant acoustic birdsong profiles consisting of repetitions of single song syllables at high frequencies. Juvenile offspring of nonrepeaters can selectively learn the syntactic rule or habit of repeating syllables from repeaters. Adult tutored syllable repeaters, unlike spontaneous repeaters, undergo a form of song plasticity involving progressive reduction of the mean number and variance of repeated syllables as a function of long-term exposure to nonrepeater songs without altering the number or sequence of syllables within motifs. These findings suggest that aspects of song syntax or temporal frame can be acquired independently of song syllable or spectral content, and plasticity involving restorative alteration of acquired variant temporal frames can occur after the closure of the critical period for song learning. PMID:14570544

  12. Early Life Manipulations of the Nonapeptide System Alter Pair Maintenance Behaviors and Neural Activity in Adult Male Zebra Finches

    PubMed Central

    Baran, Nicole M.; Tomaszycki, Michelle L.; Adkins-Regan, Elizabeth

    2016-01-01

    Adult zebra finches (T. guttata) form socially monogamous pair bonds characterized by proximity, vocal communication, and contact behaviors. In this experiment, we tested whether manipulations of the nonapeptide hormone arginine vasotocin (AVT, avian homolog of vasopressin) and the V1a receptor (V1aR) early in life altered species-typical pairing behavior in adult zebra finches of both sexes. Although there was no effect of treatment on the tendency to pair in either sex, males in different treatments exhibited profoundly different profiles of pair maintenance behavior. Following a brief separation, AVT-treated males were highly affiliative with their female partner but sang very little compared to Controls. In contrast, males treated with a V1aR antagonist sang significantly less than Controls, but did not differ in affiliation. These effects on behavior in males were also reflected in changes in the expression of V1aR and immediate early gene activity in three brain regions known to be involved in pairing behavior in birds: the medial amygdala, medial bed nucleus of the stria terminalis, and the lateral septum. AVT males had higher V1aR expression in the medial amygdala than both Control and antagonist-treated males and immediate early gene activity of V1aR neurons in the medial amygdala was positively correlated with affiliation. Antagonist treated males showed decreased activity in the medial amygdala. In addition, there was a negative correlation between the activity of V1aR cells in the medial bed nucleus of the stria terminalis and singing. Treatment also affected the expression of V1aR and activity in the lateral septum, but this was not correlated with any behaviors measured. These results provide evidence that AVT and V1aR play developmental roles in specific pair maintenance behaviors and the neural substrate underlying these behaviors in a bird. PMID:27065824

  13. Early Life Manipulations of the Nonapeptide System Alter Pair Maintenance Behaviors and Neural Activity in Adult Male Zebra Finches.

    PubMed

    Baran, Nicole M; Tomaszycki, Michelle L; Adkins-Regan, Elizabeth

    2016-01-01

    Adult zebra finches (T. guttata) form socially monogamous pair bonds characterized by proximity, vocal communication, and contact behaviors. In this experiment, we tested whether manipulations of the nonapeptide hormone arginine vasotocin (AVT, avian homolog of vasopressin) and the V1a receptor (V1aR) early in life altered species-typical pairing behavior in adult zebra finches of both sexes. Although there was no effect of treatment on the tendency to pair in either sex, males in different treatments exhibited profoundly different profiles of pair maintenance behavior. Following a brief separation, AVT-treated males were highly affiliative with their female partner but sang very little compared to Controls. In contrast, males treated with a V1aR antagonist sang significantly less than Controls, but did not differ in affiliation. These effects on behavior in males were also reflected in changes in the expression of V1aR and immediate early gene activity in three brain regions known to be involved in pairing behavior in birds: the medial amygdala, medial bed nucleus of the stria terminalis, and the lateral septum. AVT males had higher V1aR expression in the medial amygdala than both Control and antagonist-treated males and immediate early gene activity of V1aR neurons in the medial amygdala was positively correlated with affiliation. Antagonist treated males showed decreased activity in the medial amygdala. In addition, there was a negative correlation between the activity of V1aR cells in the medial bed nucleus of the stria terminalis and singing. Treatment also affected the expression of V1aR and activity in the lateral septum, but this was not correlated with any behaviors measured. These results provide evidence that AVT and V1aR play developmental roles in specific pair maintenance behaviors and the neural substrate underlying these behaviors in a bird. PMID:27065824

  14. Effect of Vocal Nerve Section on Song and ZENK Protein Expression in Area X in Adult Male Zebra Finches

    PubMed Central

    Liao, Congshu; Li, Dongfeng

    2012-01-01

    ZENK expression in vocal nuclei is associated with singing behavior. Area X is an important nucleus for learning and stabilizing birdsong. ZENK expression is higher in Area X compared to that in other vocal nuclei when birds are singing. To reveal the relationship between the ZENK expression in Area X and song crystallization, immunohistochemistry was used to detect ZENK protein expression in Area X after the unilateral vocal nerve (tracheosyringeal nerve) section in adult male zebra finches. Sham operations had no effect on song. In contrast, section of unilateral vocal nerve could induce song decrystallization at the 7th day after the surgery. The spectral and the temporal features of birdsong were distorted more significantly in the right-side vocal nerve section than in the left-side vocal nerve section. In addition, after surgery, ZENK expression was higher in the right-side of Area X than in the left-side. These results indicate that the vocal nerve innervations probably are right-side dominant. ZENK expression in both sides of Area X decreased, as compared to control group after surgery, which suggests that the ZENK expression in Area X is related to birdsong crystallization, and that there is cooperation between the Area X in AFP and syrinx nerve. PMID:23251821

  15. Mercury Reduces Avian Reproductive Success and Imposes Selection: An Experimental Study with Adult- or Lifetime-Exposure in Zebra Finch

    PubMed Central

    Varian-Ramos, Claire W.; Swaddle, John P.; Cristol, Daniel A.

    2014-01-01

    Mercury is a global pollutant that biomagnifies in food webs, placing wildlife at risk of reduced reproductive fitness and survival. Songbirds are the most diverse branch of the avian evolutionary tree; many are suffering persistent and serious population declines and we know that songbirds are frequently exposed to mercury pollution. Our objective was to determine the effects of environmentally relevant doses of mercury on reproductive success of songbirds exposed throughout their lives or only as adults. The two modes of exposure simulated philopatric species versus dispersive species, and are particularly relevant because of the heightened mercury-sensitivity of developing nervous systems. We performed a dosing study with dietary methylmercury in a model songbird species, the zebra finch (Taeniopygia guttata), at doses from 0.3 – 2.4 parts per million. Birds were exposed to mercury either as adults only or throughout their lives. All doses of mercury reduced reproductive success, with the lowest dose reducing the number of independent offspring produced in one year by 16% and the highest dose, representing approximately half the lethal dose for this species, causing a 50% reduction. While mercury did not affect clutch size or survivorship, it had the most consistent effect on the proportion of chicks that fledged from the nest, regardless of mode of exposure. Among birds exposed as adults, mercury caused a steep increase in the latency to re-nest after loss of a clutch. Birds exposed for their entire lifetimes, which were necessarily the offspring of dosed parents, had up to 50% lower reproductive success than adult-exposed birds at low doses of methylmercury, but increased reproductive success at high doses, suggesting selection for mercury tolerance at the highest level of exposure. Our results indicate that mercury levels in prey items at contaminated sites pose a significant threat to populations of songbirds through reduced reproductive success. PMID

  16. Mercury reduces avian reproductive success and imposes selection: an experimental study with adult- or lifetime-exposure in zebra finch.

    PubMed

    Varian-Ramos, Claire W; Swaddle, John P; Cristol, Daniel A

    2014-01-01

    Mercury is a global pollutant that biomagnifies in food webs, placing wildlife at risk of reduced reproductive fitness and survival. Songbirds are the most diverse branch of the avian evolutionary tree; many are suffering persistent and serious population declines and we know that songbirds are frequently exposed to mercury pollution. Our objective was to determine the effects of environmentally relevant doses of mercury on reproductive success of songbirds exposed throughout their lives or only as adults. The two modes of exposure simulated philopatric species versus dispersive species, and are particularly relevant because of the heightened mercury-sensitivity of developing nervous systems. We performed a dosing study with dietary methylmercury in a model songbird species, the zebra finch (Taeniopygia guttata), at doses from 0.3 - 2.4 parts per million. Birds were exposed to mercury either as adults only or throughout their lives. All doses of mercury reduced reproductive success, with the lowest dose reducing the number of independent offspring produced in one year by 16% and the highest dose, representing approximately half the lethal dose for this species, causing a 50% reduction. While mercury did not affect clutch size or survivorship, it had the most consistent effect on the proportion of chicks that fledged from the nest, regardless of mode of exposure. Among birds exposed as adults, mercury caused a steep increase in the latency to re-nest after loss of a clutch. Birds exposed for their entire lifetimes, which were necessarily the offspring of dosed parents, had up to 50% lower reproductive success than adult-exposed birds at low doses of methylmercury, but increased reproductive success at high doses, suggesting selection for mercury tolerance at the highest level of exposure. Our results indicate that mercury levels in prey items at contaminated sites pose a significant threat to populations of songbirds through reduced reproductive success.

  17. Developmental origins of mosaic brain evolution: Morphometric analysis of the developing zebra finch brain.

    PubMed

    Charvet, Christine J; Striedter, Georg F

    2009-05-10

    In adult zebra finches (Taeniopygia guttata), the telencephalon occupies 64% of the entire brain. This fraction is similar to what is seen in parrots, but many other birds possess a significantly smaller telencephalon. The aim of the present study was to determine the developmental time course and cellular basis of telencephalic enlargement in zebra finches, and then to compare these findings with what is known about telencephalic enlargement in other birds. To this end we estimated the volumes of all major brain regions from serial sections in embryonic and post-hatching zebra finches. We also labeled proliferating cells with antibodies against proliferating cell nuclear antigen and phosphorylated histone H3. An important finding to emerge from this work is that the telencephalon of zebra finches at hatching contains a thick proliferative subventricular zone (SVZ) that extends from the subpallium into the dorsal pallium. The data also show that the onset and offset of telencephalic neurogenesis are both delayed in zebra finches relative to quail (Galliformes). This delay in neurogenesis, in conjunction with the expanded SVZ, probably accounts for most of the telencephalic enlargement in passerines such as the zebra finch. In addition, passerines enlarged their telencephalon by decreasing the proportional size of their midbrain tectum. Because the presumptive tectum is proportionally smaller in zebra finches than quail before neurogenesis begins, this difference in tectum size cannot be due to evolutionary alterations in neurogenesis timing. Collectively these findings indicate that several different developmental mechanisms underlie the evolution of a large telencephalon in passerines.

  18. Female Zebra Finches Smell Their Eggs.

    PubMed

    Golüke, Sarah; Dörrenberg, Sebastian; Krause, E Tobias; Caspers, Barbara A

    2016-01-01

    Parental investment in unrelated offspring seems maladaptive from an evolutionary perspective, due to the costs of energy and resources that cannot be invested in related offspring at the same time. Therefore selection should favour mechanisms to discriminate between own and foreign offspring. In birds, much emphasis has been placed on understanding the visual mechanisms underlying egg recognition. However, olfactory egg recognition has almost been completely ignored. Here, we investigated whether female zebra finches (Taeniopygia guttata) are able to discriminate between their own and a conspecific egg based on olfactory cues alone. Zebra finches are colonial-breeding songbirds. Eggs are monomorphic, i.e. without any spotting pattern, and intraspecific brood parasitism frequently occurs. In a binary choice experiment, female zebra finches were given the choice between the scent of their own and a conspecific egg. After the onset of incubation, females chose randomly and showed no sign of discrimination. However, shortly before hatching, females preferred significantly the odour of their own egg. The finding that females are capable to smell their own egg may inspire more research on the potential of olfaction involved in egg recognition, especially in cases where visual cues might be limited. PMID:27192061

  19. Female Zebra Finches Smell Their Eggs

    PubMed Central

    Golüke, Sarah; Dörrenberg, Sebastian; Krause, E. Tobias; Caspers, Barbara A.

    2016-01-01

    Parental investment in unrelated offspring seems maladaptive from an evolutionary perspective, due to the costs of energy and resources that cannot be invested in related offspring at the same time. Therefore selection should favour mechanisms to discriminate between own and foreign offspring. In birds, much emphasis has been placed on understanding the visual mechanisms underlying egg recognition. However, olfactory egg recognition has almost been completely ignored. Here, we investigated whether female zebra finches (Taeniopygia guttata) are able to discriminate between their own and a conspecific egg based on olfactory cues alone. Zebra finches are colonial—breeding songbirds. Eggs are monomorphic, i.e. without any spotting pattern, and intraspecific brood parasitism frequently occurs. In a binary choice experiment, female zebra finches were given the choice between the scent of their own and a conspecific egg. After the onset of incubation, females chose randomly and showed no sign of discrimination. However, shortly before hatching, females preferred significantly the odour of their own egg. The finding that females are capable to smell their own egg may inspire more research on the potential of olfaction involved in egg recognition, especially in cases where visual cues might be limited. PMID:27192061

  20. Effects of housing condition and early corticosterone treatment on learned features of song in adult male zebra finches.

    PubMed

    Shahbazi, Mahin; Jimenez, Pedro; Martinez, Luis A; Carruth, Laura L

    2014-03-01

    Early developmental stress can have long-term physiological and behavioral effects on an animal. Developmental stress and early corticosterone (Cort) exposure affect song quality in many songbirds. Early housing condition can act as a stressor and affect the growth of nestlings and adult song, and improvements in housing condition can reverse adverse effects of early stress exposure in rodents. However, little is known about this effect in songbirds. Therefore, we took a novel approach to investigate if housing condition can modify the effects of early Cort exposure on adult song in male zebra finches. We manipulated early housing conditions to include breeding in large communal flight cages (FC; standard housing condition; with mixed-sex and mix-aged birds) versus individual breeding cages (IBC, one male-female pair with small, IBC-S, or large clutches, IBC-L) in post-hatch Cort treated male birds. We found that Cort treated birds from IBC-S have higher overall song learning scores (between tutor and pupil) than from FC but there is no difference between these groups in the No-Cort treated birds. When examining the effects of Cort within each housing condition, overall song learning scores decreased in Cort treated birds from flight cages but increased in birds from IBC-S compared to controls. Likewise, the total number of syllables and syllable types increased significantly in Cort treated birds from IBC-S, but decreased in FC-reared birds though this effect was not statistically significant. These findings suggest that the effects of early Cort treatment on learned features of song depend on housing condition.

  1. Syllable chunking in zebra finch (Taeniopygia guttata) song.

    PubMed

    Williams, H; Staples, K

    1992-09-01

    We examined how 61 young zebra finch (Taeniopygia guttata) males copied song from 5 adult tutors. Zebra finch song consists of a string of 5-15 distinct syllables, and these syllables were copied as chunks, or strings of consecutive syllables (modal length = 3). The silent interval between 2 syllables was copied as part of the syllable after the silence. Copied chunks had boundaries that fell at consistent locations within the tutor's song, marked by a relatively long intersyllable silent period, a transition between call-like and noncall-like syllables, and a tendency for the tutor male to stop his song short. Young males also tended to break their songs off at the boundaries of the chunks they had copied. Chunks appear to be an intermediate level of hierarchy in song organization and to have both perceptual (syllables were learned as part of a chunk) and motor (song delivery was broken almost exclusively at chunk boundaries) aspects. PMID:1395497

  2. Opioid modulation of song in male zebra finches (Taenopygia guttata).

    PubMed

    Khurshid, Nazia; Jayaprakash, Navin; Hameed, L Shahul; Mohanasundaram, Sivaraj; Iyengar, Soumya

    2010-04-01

    Endogenous opioids are known to modulate motivated behaviors. Male zebra finches produce a highly motivated behavior (directed song) to court females and also sing in isolation (undirected song). We found that adult male zebra finches sang significantly fewer directed and undirected songs after administration of low doses (2.5 mg/kg body weight) of the general opioid antagonist naloxone, even though the order of syllables in songs was not altered. Surprisingly, high doses of naloxone (10 mg/kg body weight) dramatically decreased the production of undirected songs but had no significant effects on directed songs. There were no changes in the number of calls during directed or undirected song, movement, stereotyped behaviors including pecking and preening, feeding or drinking behaviors after naloxone administration. We also found that treating zebra finches with naloxone led to a decrease in tonality (goodness of pitch), frequency and amplitude modulation and an increase in the length of intersyllable intervals. Our results suggest that the opioid system can differentially modulate directed and undirected song as well as the acoustic characteristics of birdsong, perhaps by acting on different components of the song control system.

  3. Neonatal nutrition, adult antioxidant defences and sexual attractiveness in the zebra finch.

    PubMed Central

    Blount, Jonathan D; Metcalfe, Neil B; Arnold, Kathryn E; Surai, Peter F; Devevey, Godefroy L; Monaghan, Pat

    2003-01-01

    Early nutrition has recently been shown to have pervasive, downstream effects on adult life-history parameters including lifespan, but the underlying mechanisms remain poorly understood. Damage to biomolecules caused by oxidants, such as free radicals generated during metabolic processes, is widely recognized as a key contributor to somatic degeneration and the rate of ageing. Lipophilic antioxidants (carotenoids, vitamins A and E) are an important component of vertebrate defences against such damage. By using an avian model, we show here that independent of later nutrition, individuals experiencing a short period of low-quality nutrition during the nestling period had a twofold reduction in plasma levels of these antioxidants at adulthood. We found no effects on adult external morphology or sexual attractiveness: in mate-choice trials females did not discriminate between adult males that had received standard- or lower-quality diet as neonates. Our results suggest low-quality neonatal nutrition resulted in a long-term impairment in the capacity to assimilate dietary antioxidants, thereby setting up a need to trade off the requirement for antioxidant activity against the need to maintain morphological development and sexual attractiveness. Such state-dependent trade-offs could underpin the link between early nutrition and senescence. PMID:12964996

  4. Song Recognition in Zebra Finches: Are There Sensitive Periods for Song Memorization?

    ERIC Educational Resources Information Center

    Braaten, Richard F.

    2010-01-01

    Male zebra finches learn to sing songs that they hear between 25 and 65 days of age, the sensitive period for song learning. In this experiment, male and female zebra finches were exposed to zebra finch songs either before (n = 9) or during (n = 4) the sensitive period. Following song exposure, recognition memory for the songs was assessed with an…

  5. Proper Care, Husbandry, and Breeding Guidelines for the Zebra Finch, Taeniopygia guttata

    PubMed Central

    Olson, Christopher R.; Wirthlin, Morgan; Lovell, Peter V.; Mello, Claudio V.

    2015-01-01

    The zebra finch Taeniopygia guttata castanotis is a songbird commonly used in the laboratory, particularly for studies of vocal learning, neurobiology, and physiology. Within the laboratory, it is important to adopt careful husbandry practices that allow for normal development of the birds. For example, their song is a learned trait, passed culturally from adult males to juveniles, and thus its learning can be influenced by the health and social conditions of the birds present in the laboratory. Here we present guidelines for the successful maintenance and breeding of captive zebra finches. PMID:25342067

  6. Interactive effects of early and later nutritional conditions on the adult antioxidant defence system in zebra finches.

    PubMed

    Noguera, José C; Monaghan, Pat; Metcalfe, Neil B

    2015-07-01

    In vertebrates, antioxidant defences comprise a mixture of endogenously produced components and exogenously obtained antioxidants that are derived mostly from the diet. It has been suggested that early-life micronutritional conditions might influence the way in which the antioxidant defence system operates, which could enable individuals to adjust the activity of the endogenous and exogenous components in line with their expected intake of dietary antioxidants if the future environment resembles the past. We investigated this possibility by experimentally manipulating the micronutrient content of the diet during different periods of postnatal development in the zebra finch (Taeniopygia guttata). Birds that had a low micronutrient diet during the growth phase initially had a lower total antioxidant capacity (TAC) than those reared under a high micronutrient diet, but then showed a compensatory response, so that by the end of the growth phase, the TAC of the two groups was the same. Interestingly, we found an interactive effect of micronutrient intake early and late in development: only those birds that continued with the same dietary treatment (low or high) throughout development showed a significant increase in their TAC during the period of sexual maturation. A similar effect was also found in the level of enzymatic antioxidant defences (glutathione peroxidase; GPx). No significant effects were found in the level of oxidative damage in lipids [malondialdehyde (MDA) levels]. These findings demonstrate the importance of early and late developmental conditions in shaping multiple aspects of the antioxidant system. Furthermore, they suggest that young birds may adjust their antioxidant defences to enable them to 'thrive' on diets rich or poor in micronutrients later in life.

  7. Vocal Tract Articulation in Zebra Finches

    PubMed Central

    Ohms, Verena R.; Snelderwaard, Peter Ch.; ten Cate, Carel; Beckers, Gabriël J. L.

    2010-01-01

    Background Birdsong and human vocal communication are both complex behaviours which show striking similarities mainly thought to be present in the area of development and learning. Recent studies, however, suggest that there are also parallels in vocal production mechanisms. While it has been long thought that vocal tract filtering, as it occurs in human speech, only plays a minor role in birdsong there is an increasing number of studies indicating the presence of sound filtering mechanisms in bird vocalizations as well. Methodology/Principal Findings Correlating high-speed X-ray cinematographic imaging of singing zebra finches (Taeniopygia guttata) to song structures we identified beak gape and the expansion of the oropharyngeal-esophageal cavity (OEC) as potential articulators. We subsequently manipulated both structures in an experiment in which we played sound through the vocal tract of dead birds. Comparing acoustic input with acoustic output showed that OEC expansion causes an energy shift towards lower frequencies and an amplitude increase whereas a wide beak gape emphasizes frequencies around 5 kilohertz and above. Conclusion These findings confirm that birds can modulate their song by using vocal tract filtering and demonstrate how OEC and beak gape contribute to this modulation. PMID:20689831

  8. Presumed Mycobacteriosis in Laboratory Zebra Finch (Taeniopygia guttata)

    PubMed Central

    Asfaw, Yohannes G; Sun, Francis J

    2010-01-01

    Husbandry staff noticed a research-naïve, young-adult, female finch tossing its head back intermittently. A second finch exhibiting similar signs was reported a few days later. Postmortem necropsy and histopathology with hematoxylin and eosin and acid-fast staining on the first finch revealed the presence of acid-fast organisms in several organs. After presumptive diagnosis of mycobacteriosis, all remaining finches housed in the same room as the first underwent necropsy and histology. Three additional finches were positive for Mycobacterium-like acid-fast organisms. Incidental findings of megabacteriosis were noted histopathologically on 2 other finches. PMID:20858369

  9. Zebra finches are sensitive to prosodic features of human speech.

    PubMed

    Spierings, Michelle J; ten Cate, Carel

    2014-07-22

    Variation in pitch, amplitude and rhythm adds crucial paralinguistic information to human speech. Such prosodic cues can reveal information about the meaning or emphasis of a sentence or the emotional state of the speaker. To examine the hypothesis that sensitivity to prosodic cues is language independent and not human specific, we tested prosody perception in a controlled experiment with zebra finches. Using a go/no-go procedure, subjects were trained to discriminate between speech syllables arranged in XYXY patterns with prosodic stress on the first syllable and XXYY patterns with prosodic stress on the final syllable. To systematically determine the salience of the various prosodic cues (pitch, duration and amplitude) to the zebra finches, they were subjected to five tests with different combinations of these cues. The zebra finches generalized the prosodic pattern to sequences that consisted of new syllables and used prosodic features over structural ones to discriminate between stimuli. This strong sensitivity to the prosodic pattern was maintained when only a single prosodic cue was available. The change in pitch was treated as more salient than changes in the other prosodic features. These results show that zebra finches are sensitive to the same prosodic cues known to affect human speech perception. PMID:24870039

  10. Complete genome sequence of a novel circovirus from zebra finch.

    PubMed

    Rinder, Monika; Schmitz, Anna; Peschel, Andrea; Korbel, Rüdiger

    2015-01-01

    A novel circovirus was identified in zebra finches (Taeniopygia guttata). The genome of the circovirus strain, designated 8454V25-1, comprised 1,982 nucleotides with two major open reading frames encoding a replication-associated protein and a viral capsid protein. PMID:26021933

  11. Zebra Finch Song Phonology and Syntactical Structure across Populations and Continents—A Computational Comparison

    PubMed Central

    Lachlan, Robert F.; van Heijningen, Caroline A. A.; ter Haar, Sita M.; ten Cate, Carel

    2016-01-01

    Learned bird songs are often characterized by a high degree of variation between individuals and sometimes between populations, while at the same time maintaining species specificity. The evolution of such songs depends on the balance between plasticity and constraints. Captive populations provide an opportunity to examine signal variation and differentiation in detail, so we analyzed adult male zebra finch (Taeniopygia guttata) songs recorded from 13 populations across the world, including one sample of songs from wild-caught males in their native Australia. Cluster analysis suggested some, albeit limited, evidence that zebra finch song units belonged to universal, species-wide categories, linked to restrictions in vocal production and non-song parts of the vocal repertoire. Across populations, songs also showed some syntactical structure, although any song unit could be placed anywhere within the song. On the other hand, there was a statistically significant differentiation between populations, but the effect size was very small, and its communicative significance dubious. Our results suggest that variation in zebra finch songs within a population is largely determined by species-wide constraints rather than population-specific features. Although captive zebra finch populations have been sufficiently isolated to allow them to genetically diverge, there does not appear to have been any divergence in the genetically determined constraints that underlie song learning. Perhaps more surprising is the lack of locally diverged cultural traditions. Zebra finches serve as an example of a system where frequent learning errors may rapidly create within-population diversity, within broad phonological and syntactical constraints, and prevent the formation of long-term cultural traditions that allow populations to diverge. PMID:27458396

  12. Zebra Finch Song Phonology and Syntactical Structure across Populations and Continents-A Computational Comparison.

    PubMed

    Lachlan, Robert F; van Heijningen, Caroline A A; Ter Haar, Sita M; Ten Cate, Carel

    2016-01-01

    Learned bird songs are often characterized by a high degree of variation between individuals and sometimes between populations, while at the same time maintaining species specificity. The evolution of such songs depends on the balance between plasticity and constraints. Captive populations provide an opportunity to examine signal variation and differentiation in detail, so we analyzed adult male zebra finch (Taeniopygia guttata) songs recorded from 13 populations across the world, including one sample of songs from wild-caught males in their native Australia. Cluster analysis suggested some, albeit limited, evidence that zebra finch song units belonged to universal, species-wide categories, linked to restrictions in vocal production and non-song parts of the vocal repertoire. Across populations, songs also showed some syntactical structure, although any song unit could be placed anywhere within the song. On the other hand, there was a statistically significant differentiation between populations, but the effect size was very small, and its communicative significance dubious. Our results suggest that variation in zebra finch songs within a population is largely determined by species-wide constraints rather than population-specific features. Although captive zebra finch populations have been sufficiently isolated to allow them to genetically diverge, there does not appear to have been any divergence in the genetically determined constraints that underlie song learning. Perhaps more surprising is the lack of locally diverged cultural traditions. Zebra finches serve as an example of a system where frequent learning errors may rapidly create within-population diversity, within broad phonological and syntactical constraints, and prevent the formation of long-term cultural traditions that allow populations to diverge. PMID:27458396

  13. Zebra Finch Song Phonology and Syntactical Structure across Populations and Continents-A Computational Comparison.

    PubMed

    Lachlan, Robert F; van Heijningen, Caroline A A; Ter Haar, Sita M; Ten Cate, Carel

    2016-01-01

    Learned bird songs are often characterized by a high degree of variation between individuals and sometimes between populations, while at the same time maintaining species specificity. The evolution of such songs depends on the balance between plasticity and constraints. Captive populations provide an opportunity to examine signal variation and differentiation in detail, so we analyzed adult male zebra finch (Taeniopygia guttata) songs recorded from 13 populations across the world, including one sample of songs from wild-caught males in their native Australia. Cluster analysis suggested some, albeit limited, evidence that zebra finch song units belonged to universal, species-wide categories, linked to restrictions in vocal production and non-song parts of the vocal repertoire. Across populations, songs also showed some syntactical structure, although any song unit could be placed anywhere within the song. On the other hand, there was a statistically significant differentiation between populations, but the effect size was very small, and its communicative significance dubious. Our results suggest that variation in zebra finch songs within a population is largely determined by species-wide constraints rather than population-specific features. Although captive zebra finch populations have been sufficiently isolated to allow them to genetically diverge, there does not appear to have been any divergence in the genetically determined constraints that underlie song learning. Perhaps more surprising is the lack of locally diverged cultural traditions. Zebra finches serve as an example of a system where frequent learning errors may rapidly create within-population diversity, within broad phonological and syntactical constraints, and prevent the formation of long-term cultural traditions that allow populations to diverge.

  14. Colour preferences in nest-building zebra finches.

    PubMed

    Muth, Felicity; Steele, Matthew; Healy, Susan D

    2013-10-01

    Some bird species are selective in the materials they choose for nest building, preferring, for example, materials of one colour to others. However, in many cases the cause of these preferences is not clear. One of those species is the zebra finch, which exhibits strong preferences for particular colours of nest material. In an attempt to determine why these birds strongly prefer one colour of material over another, we compared the preferences of paired male zebra finches for nest material colour with their preferences for food of the same colours. We found that birds did indeed prefer particular colours of nest material (in most cases blue) but that they did not generally prefer food of one colour over the other colours. It appears, then, that a preference for one colour or another of nest material is specific to the nest-building context. This article is part of a Special Issue entitled: insert SI title.

  15. Timbre discrimination in zebra finch (Taeniopygia guttata) song syllables.

    PubMed

    Cynx, J; Williams, H; Nottebohm, F

    1990-12-01

    Zebra finch (Taeniopygia guttata) songs include syllables of a fundamental frequency and harmonics. Individual harmonics in 1 syllable can be more or less emphasized. The functional role of this variability is unknown. These experiments provide evidence of how the phenomenon is perceived. We trained 12 male and female zebra finches on a go-no-go operant procedure to discriminate between 2 song syllables that varied only in the absence of the 2nd or 5th harmonic. Training involved many thousands of trials. Both sexes used the presence or absence of the 2nd harmonic as the sole discriminative cue. Females had more difficulty learning to perform the task when the presence of the 2nd harmonic was the go stimulus, which indicates that their use of the information was biased by stimulus-response contingencies. The results are discussed in terms of a broad strategy to understand how animals perceive sounds used in communication.

  16. Same-sex partner preference in zebra finches: pairing flexibility and choice.

    PubMed

    Tomaszycki, Michelle L; Zatirka, Brendon P

    2014-11-01

    This study examined flexibility and choice in same-sex pair-bonding behavior in adult zebra finches (Taeniopygia guttata). Zebra finches form life-long monogamous relationships and extra pair behavior is very low, making them an ideal species in which to study same-sex pairing. We examined same-sex behaviors using both semi-naturalistic choice paradigms and skewed sex ratios. In the first experiment, we allowed zebra finches to pair in aviaries with equal sex ratios as part of multiple experiments. On average, 6.4% (N = 78) of unmanipulated pairs were same-sex: all but one was female-female. In a second experiment, we identified pairs from same-sex cages and selected 20 total same-sex pairs (10 of each sex). We then gave pairs a chance to court and pair with members of the opposite sex and observed their behavior for three days. Females did not retain their partner, but most paired with males. In contrast, some males did retain their partner. Similarly, females were more likely to engage in pairing behaviors with males than with their partners or other females whereas males were equally likely to engage in same-sex and opposite-sex pairing behaviors. These findings suggest that same-sex partnerships in zebra finches can be facultative, based on the sex ratio of the group in which they live, but can also be a choice, when opportunities to pair with opposite-sex individuals are possible. Furthermore, it is possible that females are more flexible in this choice of same-sex partnerships than are males.

  17. Parental influence on begging call structure in zebra finches (Taeniopygia guttata): evidence of early vocal plasticity

    PubMed Central

    Villain, Avelyne S.; Boucaud, Ingrid C. A.; Bouchut, Colette; Vignal, Clémentine

    2015-01-01

    Begging calls are signals of need used by young birds to elicit care from adults. Different theoretical frameworks have been proposed to understand this parent–offspring communication. But relationships between parental response and begging intensity, or between begging characteristics and proxies of a young’s need remain puzzling. Few studies have considered the adjustment of nestling begging features to previous experience as a possible explanation of these discrepancies. In this study, we tested the effect of a heterospecific rearing environment on individual developmental trajectories of the acoustic structure of nestling begging calls. Fifty-two zebra finch chicks were fostered either to Bengalese finch or to zebra finch parents, and begging calls were recorded at several stages of nestling development. Acoustic analyses revealed that the development of the spectral features of the begging calls differed between experimental conditions: chicks reared by Bengalese finches produced higher pitched and less broadband begging calls than chicks reared by conspecific parents. Differences were stronger in males than females and were not explained by differences in growth rate. We conclude that nestling begging calls can be plastic in response to social interactions with parents. PMID:26716009

  18. Maternal effects in quail and zebra finches: Behavior and hormones.

    PubMed

    Adkins-Regan, Elizabeth; Banerjee, Sunayana B; Correa, Stephanie M; Schweitzer, Cécile

    2013-09-01

    Maternal effects are influences of parents on offspring phenotype occurring through pathways other than inherited DNA. In birds, two important routes for such transmission are parental behavior and non-DNA egg constituents such as yolk hormones. Offspring traits subject to parental effects include behavior and endocrine function. Research from the Adkins-Regan lab has used three avian species to investigate maternal effects related to hormones and behavior. Experiments with chickens and Japanese quail have shown that maternal sex steroids can influence sex determination to produce biased offspring sex ratios. Because all birds have a ZZ/ZW chromosomal sex determining system in which the female parent determines the sex of the offspring, these results raise the possibility that maternal steroids can influence the outcome of sex chromosome meiosis. Learning has been shown to influence egg investment by female quail in ways that are likely to alter offspring phenotype. In quail, embryonic and exogenous sex steroids have well established and long-lasting effects on sexual differentiation of behavior during a critical period in ovo, but elevated yolk testosterone has long-term effects on behavior that do not seem to be occurring through an alteration in sexual differentiation. In biparental zebra finches, removal of mothers alters not only later behavior, but also the adult response of the hypothalamic-pituitary-adrenal (HPA) axis to an environmental stressor, as indicated by plasma corticosterone. Birds raised only by fathers have lower levels of mRNA for both glucocorticoid receptors in several brain regions as adults. These studies add to the evidence that one generation influences the behavioral or endocrine phenotype of the next through routes other than transmission of DNA. Additional research will be required to understand the adaptive significance of these effects.

  19. The acoustic effect of vocal tract adjustments in zebra finches

    PubMed Central

    Riede, Tobias; Schilling, Nadja; Goller, Franz

    2012-01-01

    Vocal production in songbirds requires the control of the respiratory system, the syrinx as sound source and the vocal tract as acoustic filter. Vocal tract movements consist of beak, tongue and hyoid movements which change the volume of the oropharyngeal-esophageal cavity (OEC), glottal movements and tracheal length changes. The respective contributions of each movement to filter properties are not completely understood, but the effects of this filtering are thought to be very important for acoustic communication in birds. One of the most striking movements of the upper vocal tract during vocal behavior in songbirds involves the OEC. This study measured the acoustic effect of OEC adjustments in zebra finches by comparing resonance acoustics between an utterance with OEC expansion (calls) and a similar utterance without OEC expansion (respiratory sounds induced by a bilateral syringeal denervation). X-ray cineradiography confirmed the presence of an OEC motor pattern during song and call production, and a custom-built Hall-effect collar system confirmed that OEC expansion movements were not present during respiratory sounds. The spectral emphasis during zebra finch call production ranging between 2.5 and 5 kHz was not present during respiratory sounds, indicating strongly that it can be attributed to the OEC expansion. PMID:23085986

  20. Zebra finches are able to learn affixation-like patterns.

    PubMed

    Chen, Jiani; Jansen, Naomi; ten Cate, Carel

    2016-01-01

    Adding an affix to transform a word is common across the world languages, with the edges of words more likely to carry out such a function. However, detecting affixation patterns is also observed in learning tasks outside the domain of language, suggesting that the underlying mechanism from which affixation patterns have arisen may not be language or even human specific. We addressed whether a songbird, the zebra finch, is able to discriminate between, and generalize, affixation-like patterns. Zebra finches were trained and tested in a Go/Nogo paradigm to discriminate artificial song element sequences resembling prefixed and suffixed 'words.' The 'stems' of the 'words,' consisted of different combinations of a triplet of song elements, to which a fourth element was added as either a 'prefix' or a 'suffix.' After training, the birds were tested with novel stems, consisting of either rearranged familiar element types or novel element types. The birds were able to generalize the affixation patterns to novel stems with both familiar and novel element types. Hence, the discrimination resulting from the training was not based on memorization of individual stimuli, but on a shared property among Go or Nogo stimuli, i.e., affixation patterns. Remarkably, birds trained with suffixation as Go pattern showed clear evidence of using both prefix and suffix, while those trained with the prefix as the Go stimulus used primarily the prefix. This finding illustrates that an asymmetry in attending to different affixations is not restricted to human languages. PMID:26297477

  1. Amyloidosis in a Captive Zebra Finch (Taeniopygia guttata) Research Colony.

    PubMed

    Shientag, Lisa J; Garlick, David S; Galati, Erin

    2016-01-01

    Five birds in a captive zebra finch research colony were diagnosed with systemic amyloidosis within a 7-mo period by means of postmortem Congo red staining and green birefringence under polarized light. The liver was the most frequently and usually the most seriously affected organ, followed by the spleen and then the kidney. All 5 birds had been clinically affected with various inflammatory, infectious, and neoplastic conditions associated with amyloid A (AA) amyloidosis in humans and animals. Immunohistochemistry using antisera against duck AA protein revealed that tissues from 2 of the 5 birds were positive for the presence of AA protein and systemic inflammation-associated amyloidosis. Although the development of AA amyloidosis has been associated with chronic inflammation, trauma, and various infectious and neoplastic diseases as well as possible genetic predispositions and stresses linked to overcrowding, the root causes for individual cases of AA amyloidosis are incompletely understood. As far as we know, this report is the first description of AA amyloidosis in captive, research zebra finches. PMID:27298248

  2. Nestling diet, secondary sexual traits and fitness in the zebra finch

    PubMed Central

    Birkhead, T. R.; Fletcher, F.; Pellatt, E. J.

    1999-01-01

    We examined the effect of nestling diet quality on a suite of physiological, morphological and life-history traits in adult male zebra finches, Taeniopygia guttata. Compared with birds reared on a supplemented diet, nestlings reared on a seed-only diet showed a reduced rate of growth and reduced cell-mediated immune function as measured by an in vivo response to a T lymphocyte-dependent mitogen. There were no differences between birds reared on the two diets in any of the following adult traits: body size, primary sexual traits (testes mass, numbers of stored sperm, sperm function, velocity and morphology), secondary sexual traits (beak colour and song rate), serological traits or immunological traits. The only differences we detected were a lower body mass and a greater proportion of individuals with plumage abnormalities among those reared on a seed-only diet (this latter effect was transient). The fact that male zebra finches reared on a seed-only diet were, as adults, virtually indistinguishable from those reared on a supplemented diet, despite having reduced growth and immune function as nestlings, demonstrates that they subsequently compensated through the differential allocation of resources. Our results indicate that differential allocation is costly in terms of fitness since birds reared on a seed-only diet experienced a significantly greater mortality rate than those reared on a supplemented diet. This in turn suggests the existence of a trade-off between the development of traits important for reproduction, such as primary and secondary sexual traits and longevity.

  3. Behavioural and physiological effects of population density on domesticated Zebra Finches (Taeniopygia guttata) held in aviaries.

    PubMed

    Poot, Hanneke; ter Maat, Andries; Trost, Lisa; Schwabl, Ingrid; Jansen, René F; Gahr, Manfred

    2012-02-01

    Zebra Finches (Taeniopygia guttata) are highly social and monogamous birds that display relatively low levels of aggression and coordinate group life mainly by means of vocal communication. In the wild, small groups may congregate to larger flocks of up to 150-350 birds. Little is known, however, about possible effects of population density on development in captivity. Investigating density effects on physiology and behaviour might be helpful in identifying optimal group size, in order to optimise Zebra Finch wellbeing. A direct effect of population density on development and reproduction was found: birds in lower density conditions produced significantly more and larger (body mass, tarsus length) surviving offspring than birds in high density conditions. Furthermore, offspring in low density aviaries produced slightly longer song motifs and more different syllables than their tutors, whereas offspring in high density aviaries produced shorter motifs and a smaller or similar number of different syllables than their tutors. Aggression levels within the populations were low throughout the experiment, but the number of aggressive interactions was significantly higher in high density aviaries. Baseline corticosterone levels did not differ significantly between high- and low density aviaries for either adult or offspring birds. On day 15 post hatching, brood size and baseline corticosterone levels were positively correlated. On days 60 and 100 post hatching this correlation was no longer present. The results of this study prove that population density affects various aspects of Zebra Finch development, with birds living in low population density conditions having an advantage over those living under higher population density conditions.

  4. The zebra finch, Taeniopygia guttata: an avian model for investigating the neurobiological basis of vocal learning.

    PubMed

    Mello, Claudio V

    2014-12-01

    Songbirds are capable of learning their vocalizations by copying a singing adult. This vocal learning ability requires juveniles to hear and memorize the sound of the adult song, and later to imitate it through a process involving sensorimotor integration. Vocal learning is a trait that songbirds share with humans, where it forms the basis of spoken language acquisition, with other avian groups (parrots and hummingbirds), and with a few other mammals (cetaceans, bats). It is however absent in traditional model organisms such as rodents and nonhuman primates. Zebra finches, a songbird species from Australia, are popular pets and are easy to breed. They also sing a relatively simple and stereotyped song that is amenable to quantitative analysis. Zebra finches have thus emerged as a choice model organism for investigating the neurobiological basis of vocal learning. A number of tools and methodologies have been developed to characterize the bioacoustics properties of their song, analyze the degree of accurate copying during vocal learning, map the brain circuits that control singing and song learning, and investigate the physiology of these circuits. Such studies have led to a large base of knowledge on song production and learning, and their underlying neural substrate. Several molecular resources have recently become available, including brain cDNA/EST databases, microarrays, BAC libraries, a molecular brain atlas, a complete genome assembly, and the ability to perform transgenesis. The recent availability of many other avian genomes provides unique opportunities for comparative analysis in the search for features unique to vocal learning organisms. PMID:25342070

  5. Lipid imaging in the zebra finch brain with secondary ion mass spectrometry

    NASA Astrophysics Data System (ADS)

    Amaya, Kensey R.; Monroe, Eric B.; Sweedler, Jonathan V.; Clayton, David F.

    2007-02-01

    Lipids have diverse functions in the nervous system, but the study of their anatomical distributions in the intact brain is rather difficult using conventional methodologies. Here we demonstrate the application of high resolution time-of-flight (ToF) secondary ion mass spectrometry (SIMS) to image various lipid components and cholesterol across an entire brain section prepared from an adult zebra finch (Taeniopygia guttata), with a spatial resolution of 2.3 [mu]m, resulting in the formation of 11.5 megapixel chemical images. The zebra finch is a songbird in which specific neural and developmental functions have been ascribed to discrete "song control nuclei" of the forebrain. We have observed a relative increase of palmitic acid C16:0 and oleic acid C18:1 in song control nuclei versus the surrounding tissue, while phosphate (PO3-), representative of phospholipids, was lower in these regions. Cholesterol was present at a high level only in the white matter of the optic tectum. More diffuse distributions were observed for stearic, arachidonic, linolenic, and palmitoleic acids. The presented results illustrate that SIMS imaging is a useful approach for assessing changes in lipid content during song circuit development and song learning.

  6. Autoradiographic localization of nicotinic acetylcholine receptors in the brain of the zebra finch (Poephila guttata)

    SciTech Connect

    Watson, J.T.; Adkins-Regan, E.; Whiting, P.; Lindstrom, J.M.; Podleski, T.R.

    1988-08-08

    We have localized nicotinic acetylcholine receptors in the zebra finch brain by using three 125I-labelled ligands: alpha bungarotoxin and two monoclonal antibodies to neuronal nicotinic receptors. Unfixed brains from intact adult male and female zebra finches were prepared for in vitro autoradiography. Low-resolution film autoradiograms and high-resolution emulsion autoradiograms were prepared for each of the three ligands. The major brain structures that bind all three of the ligands are hippocampus; hyperstriatum dorsalis; hyperstriatum ventralis; nucleus lentiformis mesencephali; nucleus pretectalis, some layers of the optic tectum; nucleus mesencephalicus lateralis; pars dorsalis; locus ceruleus; and all cranial motor nuclei except nucleus nervi hypoglossi. The major structures labelled only by (125I)-alpha bungarotoxin binding included hyperstriatum accessorium and the nuclei: preopticus medialis, medialis hypothalami posterioris, semilunaris, olivarius inferior, and the periventricular organ. Of the song control nuclei, nucleus magnocellularis of the anterior neostriatum; hyperstriatum ventralis, pars caudalis; nucleus intercollicularis; and nucleus hypoglossus were labelled. The binding patterns of the two antibodies were similar to one another but not identical. Both labelled nucleus spiriformis lateralis and nucleus geniculatus lateralis, pars ventralis especially heavily and also labelled the nucleus habenula medialis; nucleus subpretectalis; nucleus isthmi, pars magnocellularis; nucleus reticularis gigantocellularis; nucleus reticularis lateralis; nucleus tractus solitarii; nucleus vestibularis dorsolateralis; nucleus vestibularis lateralis; nucleus descendens nervi trigemini; and the deep cerebellar nuclei.

  7. Juvenile zebra finches learn the underlying structural regularities of their fathers’ song

    PubMed Central

    Menyhart, Otília; Kolodny, Oren; Goldstein, Michael H.; DeVoogd, Timothy J.; Edelman, Shimon

    2015-01-01

    Natural behaviors, such as foraging, tool use, social interaction, birdsong, and language, exhibit branching sequential structure. Such structure should be learnable if it can be inferred from the statistics of early experience. We report that juvenile zebra finches learn such sequential structure in song. Song learning in finches has been extensively studied, and it is generally believed that young males acquire song by imitating tutors (Zann, 1996). Variability in the order of elements in an individual’s mature song occurs, but the degree to which variation in a zebra finch’s song follows statistical regularities has not been quantified, as it has typically been dismissed as production error (Sturdy et al., 1999). Allowing for the possibility that such variation in song is non-random and learnable, we applied a novel analytical approach, based on graph-structured finite-state grammars, to each individual’s full corpus of renditions of songs. This method does not assume syllable-level correspondence between individuals. We find that song variation can be described by probabilistic finite-state graph grammars that are individually distinct, and that the graphs of juveniles are more similar to those of their fathers than to those of other adult males. This grammatical learning is a new parallel between birdsong and language. Our method can be applied across species and contexts to analyze complex variable learned behaviors, as distinct as foraging, tool use, and language. PMID:26005428

  8. Horizontal transmission of the father's song in the zebra finch (Taeniopygia guttata)

    PubMed Central

    Derégnaucourt, Sébastien; Gahr, Manfred

    2013-01-01

    As is the case for human speech, birdsong is transmitted across generations by imitative learning. Although transfer of song patterns from adults to juveniles typically occurs via vertical or oblique transmission, there is also evidence of horizontal transmission between juveniles of the same generation. Here, we show that a young male zebra finch (Taeniopygia guttata) that has been exposed to its father during the sensitive period for song learning can lead a brother, that has never heard the paternal song, to imitate some sounds of the father. Moreover, song similarity between the two brothers was higher than the similarity measured between the paternal song and the song of the brother that had a week-long exposure to the father. We speculate that the phenomenon of within-generation song learning among juveniles may be more widespread than previously thought and that when a juvenile evaluates potential models for imitative learning, a sibling may be as salient as an adult. PMID:23760166

  9. Development of temporal structure in zebra finch song

    PubMed Central

    Troyer, Todd W.

    2013-01-01

    Zebra finch song has provided an excellent case study in the neural basis of sequence learning, with a high degree of temporal precision and tight links with precisely timed bursting in forebrain neurons. To examine the development of song timing, we measured the following four aspects of song temporal structure at four age ranges between 65 and 375 days posthatch: the mean durations of song syllables and the silent gaps between them, timing variability linked to song tempo, timing variability expressed independently across syllables and gaps, and transition probabilities between consecutive syllable pairs. We found substantial increases in song tempo between 65 and 85 days posthatch, due almost entirely to a shortening of gaps. We also found a decrease in tempo variability, also specific to gaps. Both the magnitude of the increase in tempo and the decrease in tempo variability were correlated on gap-by-gap basis with increases in the reliability of corresponding syllable transitions. Syllables had no systematic increase in tempo or decrease in tempo variability. In contrast to tempo parameters, both syllables and gaps showed an early sharp reduction in independent variability followed by continued reductions over the first year. The data suggest that links between syllable-based representations are strengthened during the later parts of the traditional period of song learning and that song rhythm continues to become more regular throughout the first year of life. Similar learning patterns have been identified in human sequence learning, suggesting a potentially rich area of comparative research. PMID:23175805

  10. The perception of regularity in an isochronous stimulus in zebra finches (Taeniopygia guttata) and humans.

    PubMed

    van der Aa, Jeroen; Honing, Henkjan; ten Cate, Carel

    2015-06-01

    Perceiving temporal regularity in an auditory stimulus is considered one of the basic features of musicality. Here we examine whether zebra finches can detect regularity in an isochronous stimulus. Using a go/no go paradigm we show that zebra finches are able to distinguish between an isochronous and an irregular stimulus. However, when the tempo of the isochronous stimulus is changed, it is no longer treated as similar to the training stimulus. Training with three isochronous and three irregular stimuli did not result in improvement of the generalization. In contrast, humans, exposed to the same stimuli, readily generalized across tempo changes. Our results suggest that zebra finches distinguish the different stimuli by learning specific local temporal features of each individual stimulus rather than attending to the global structure of the stimuli, i.e., to the temporal regularity.

  11. Infestation of Research Zebra Finch Colony with 2 Novel Mite Species

    PubMed Central

    Siddalls, Monica; Currier, Timothy A; Pang, Jassia; Lertpiriyapong, Kvin; Patterson, Mary M

    2015-01-01

    A zebra finch (Taeniopygia guttata) housed in a neuroscience laboratory was observed to have numerous feather mites. Subsequently, similar mites were found on other birds in the animal facility and research space. The most abundant mite was a novel, undescribed species in the genus Neocheyletiella. Whereas known Neocheyletiella mites have previously been characterized as skin parasites of various birds worldwide, the species on the zebra finches is unique because it lives and builds nests in the feathers. Infrequent specimens of a ‘true’ feather mite, a new species of Megninialges, were present also. Although multiple treatments using a pyrethrin spray were effective in eradicating the mites, topical ivermectin later was found to be more efficacious, better tolerated by the birds, and less labor intensive. This case highlights the general dearth of information regarding ectoparasites in zebra finches, even though these are the most frequently used songbirds in biomedical research. The mite epizootic also underscores the diverse pathogens possible in zebra finches that arrive from outside sources and why ongoing health monitoring of finch colonies is warranted. PMID:25730757

  12. Digit ratio varies with sex, egg order and strength of mate preference in zebra finches.

    PubMed Central

    Burley, Nancy Tyler; Foster, Valerie Suzanne

    2004-01-01

    The steroid environment encountered by developing vertebrates has important organizational effects on physiology and behaviour that persist throughout an organism's lifetime. Optimal allocation of maternal steroids to zygotes may be difficult to achieve because of the sexually antagonistic effects of steroids; thus, for example, a hormone environment beneficial to a developing male may be much less beneficial to a developing female. Research into the important topic of how mothers might adaptively adjust steroid titres experienced by particular young has been constrained by the difficulty of measuring the steroid environment experienced by the embryo at critical times in development. A potential approach to this problem has been suggested by research on variation in digit ratios in humans, where the ratio of the length of the second and fourth digits reflects the steroid environment experienced by the foetus; notably, digit 4 lengthens in response to androgens. In light of the conservative nature of homeobox genes regulating early development in tetrapods, we questioned whether a sex difference in digit ratio exists in a passerine bird, the zebra finch, Taeniopygia guttata castanotis, and whether observed variation in the ratio is consistent with the previously reported pattern that androgen allocation to zebra finch egg yolk declines across laying order. We established an aviary population of outbred, wild-type zebra finches, and allowed them to breed freely. Hatchlings were marked to correspond to their egg order, and their digit ratios were measured after birds reached adulthood. We found that digit ratio increased across egg order, which is consistent with a pattern of decreasing androgen allocation. Moreover, digit ratios differed between the sexes. We also investigated whether variation in digit ratio among adult females predicted variation in their performance in mate-choice tests. Digit ratio accounted for almost 50% of the variance in strength of female

  13. The Zebra Finch, Taeniopygia guttata: An Avian Model for Investigating the Neurobiological Basis of Vocal Learning

    PubMed Central

    Mello, Claudio V.

    2015-01-01

    Songbirds are capable of learning their vocalizations by copying a singing adult. This vocal learning ability requires juveniles to hear and memorize the sound of the adult song, and later to imitate that song through a process involving sensorimotor integration. Vocal learning is a trait that songbirds share with humans, where it forms the basis of spoken language acquisition, with other avian groups (parrots and hummingbirds), and with a few other mammals (cetaceans, bats). It is however absent in traditional model organisms like rodents and non-human primates. Zebra finches, a songbird species from Australia, are popular pets, as they have attractive plumage and social behaviors and are easy to breed. They also sing a relatively simple and stereotyped song that is very amenable to quantitative analysis. Zebra finches have thus emerged as a choice model organism for investigating the neurobiological basis of vocal learning. A number of tools and methodologies have been developed to characterize the bioacoustics properties of their song, analyze the degree of accurate copying during vocal learning, map the brain circuits that control singing and song learning, and investigate the physiology of these circuits. Such studies have led to a large base of knowledge on song production and learning, and their underlying neural substrate. Several molecular resources have recently become available, including brain cDNA/EST databases, microarrays, BAC libraries, a molecular brain atlas, a complete genome assembly, and the ability to perform transgenesis. The recent availability of many other avian genomes provides unique opportunities for comparative analysis in the search of features unique to vocal learning organisms. PMID:25342070

  14. Dynamic gene expression in the song system of zebra finches during the song learning period.

    PubMed

    Olson, Christopher R; Hodges, Lisa K; Mello, Claudio V

    2015-12-01

    The brain circuitry that controls song learning and production undergoes marked changes in morphology and connectivity during the song learning period in juvenile zebra finches, in parallel to the acquisition, practice and refinement of song. Yet, the genetic programs and timing of regulatory change that establish the neuronal connectivity and plasticity during this critical learning period remain largely undetermined. To address this question, we used in situ hybridization to compare the expression patterns of a set of 30 known robust molecular markers of HVC and/or area X, major telencephalic song nuclei, between adult and juvenile male zebra finches at different ages during development (20, 35, 50 days post-hatch, dph). We found that several of the genes examined undergo substantial changes in expression within HVC or its surrounds, and/or in other song nuclei. They fit into broad patterns of regulation, including those whose expression within HVC during this period increases (COL12A1, COL 21A1, MPZL1, PVALB, and CXCR7) or decreases (e.g., KCNT2, SAP30L), as well as some that show decreased expression in the surrounding tissue with little change within song nuclei (e.g. SV2B, TAC1). These results reveal a broad range of molecular changes that occur in the song system in concert with the song learning period. Some of the genes and pathways identified are potential modulators of the developmental changes associated with the emergence of the adult properties of the song control system, and/or the acquisition of learned vocalizations in songbirds.

  15. Myosin heavy-chain isoforms in the flight and leg muscles of hummingbirds and zebra finches.

    PubMed

    Velten, Brandy P; Welch, Kenneth C

    2014-06-01

    Myosin heavy chain (MHC) isoform complement is intimately related to a muscle's contractile properties, yet relatively little is known about avian MHC isoforms or how they may vary with fiber type and/or the contractile properties of a muscle. The rapid shortening of muscles necessary to power flight at the high wingbeat frequencies of ruby-throated hummingbirds and zebra finches (25-60 Hz), along with the varied morphology and use of the hummingbird hindlimb, provides a unique opportunity to understand how contractile and morphological properties of avian muscle may be reflected in MHC expression. Isoforms of the hummingbird and zebra finch flight and hindlimb muscles were electrophoretically separated and compared with those of other avian species representing different contractile properties and fiber types. The flight muscles of the study species operate at drastically different contraction rates and are composed of different histochemically defined fiber types, yet each exhibited the same, single MHC isoform corresponding to the chicken adult fast isoform. Thus, despite quantitative differences in the contractile demands of flight muscles across species, this isoform appears necessary for meeting the performance demands of avian powered flight. Variation in flight muscle contractile performance across species may be due to differences in the structural composition of this conserved isoform and/or variation within other mechanically linked proteins. The leg muscles were more varied in their MHC isoform composition across both muscles and species. The disparity in hindlimb MHC expression between hummingbirds and the other species highlights previously observed differences in fiber type composition and thrust production during take-off.

  16. Early estrogen treatment of female zebra finches masculinizes the brain pathway for learned vocalizations.

    PubMed

    Simpson, H B; Vicario, D S

    1991-10-01

    Telencephalic nucleus HVC and its two efferent targets, RA and X, play essential roles in the production of complex, learned vocalizations in the male zebra finch. Normal females do not produce these learned vocalizations; HVC, RA, and X are small in volume, and HVC and RA are not synaptically connected. We have shown that estrogen treatment during development causes females to learn and produce male-like vocalizations. This article describes the neural masculinization of these E2 females, replicating and extending the work of others. Female zebra finches were treated with 17 beta-estradiol (E2) at hatching, at 14-22 days of age, or as adults. In adulthood, the volumes of nucleus RA and area X were measured and the efferent projections of nucleus HVC examined using the anterograde tracer PHA-L. Early, sustained E2 treatment caused the greatest increase in the volume of RA and X, the innervation of RA and X by HVC axons, and the masculinization of auditory responses of cells in RA. Treatments that lasted for a shorter period or started later in development resulted in different patterns of partial brain masculinization. E2 treatment in adulthood had no effect on the volume of RA or X or their innervation by HVC. Bilateral lesions of the tracheosyringeal nerves or of HVC had the same effects on the male-typical vocalizations produced by E2 females as they do on the vocalizations produced by males. These results demonstrate that the neural masculinization of telencephalic nuclei induced by E2 treatment sets up a functional circuit in females similar to one in males that enables the learning and production of complex vocalizations.

  17. Regulatory Differences in Natal Down Development between Altricial Zebra Finch and Precocial Chicken.

    PubMed

    Chen, Chih-Kuan; Ng, Chen Siang; Wu, Siao-Man; Chen, Jiun-Jie; Cheng, Po-Liang; Wu, Ping; Lu, Mei-Yeh Jade; Chen, Di-Rong; Chuong, Cheng-Ming; Cheng, Hsu-Chen; Ting, Chau-Ti; Li, Wen-Hsiung

    2016-08-01

    Birds can be classified into altricial and precocial. The hatchlings of altricial birds are almost naked, whereas those of precocial birds are covered with natal down. This regulatory divergence is thought to reflect environmental adaptation, but the molecular basis of the divergence is unclear. To address this issue, we chose the altricial zebra finch and the precocial chicken as the model animals. We noted that zebra finch hatchlings show natal down growth suppressed anterior dorsal (AD) skin but partially down-covered posterior dorsal (PD) skin. Comparing the transcriptomes of AD and PD skins, we found that the feather growth promoter SHH (sonic hedgehog) was expressed higher in PD skin than in AD skin. Moreover, the data suggested that the FGF (fibroblast growth factor)/Mitogen-activated protein kinase (MAPK) signaling pathway is involved in natal down growth suppression and that FGF16 is a candidate upstream signaling suppressor. Ectopic expression of FGF16 on chicken leg skin showed downregulation of SHH, upregulation of the feather growth suppressor FGF10, and suppression of feather bud elongation, similar to the phenotype found in zebra finch embryonic AD skin. Therefore, we propose that FGF16-related signals suppress natal down elongation and cause the naked AD skin in zebra finch. Our study provides insights into the regulatory divergence in natal down formation between precocial and altricial birds.

  18. Identification of auditory distance cues by zebra finches (Taeniopygia guttata) and budgerigars (Melopsittacus undulatus).

    PubMed

    Radziwon, Kelly E; Welch, Thomas E; Cone, Jarrod P; Dent, Micheal L

    2011-05-01

    The present study examined auditory distance perception cues in a non-territorial songbird, the zebra finch (Taeniopygia guttata), and in a non-songbird, the budgerigar (Melopsittacus undulatus). Using operant conditioning procedures, three zebra finches and three budgerigars were trained to identify 1- (Near) and 75-m (Far) recordings of three budgerigar contact calls, one male zebra finch song, and one female zebra finch call. Once the birds were trained on these endpoint stimuli, other stimuli were introduced into the operant task. These stimuli included recordings at intermediate distances and artificially altered stimuli simulating changes in overall amplitude, high-frequency attenuation, reverberation, and all three cues combined. By examining distance cues (amplitude, high-frequency attenuation, and reverberation) separately, this study sought to determine which cue was the most salient for the birds. The results suggest that both species could scale the stimuli on a continuum from Near to Far and that amplitude was the most important cue for these birds in auditory distance perception, as in humans and other animals. PMID:21568439

  19. Regulatory Differences in Natal Down Development between Altricial Zebra Finch and Precocial Chicken.

    PubMed

    Chen, Chih-Kuan; Ng, Chen Siang; Wu, Siao-Man; Chen, Jiun-Jie; Cheng, Po-Liang; Wu, Ping; Lu, Mei-Yeh Jade; Chen, Di-Rong; Chuong, Cheng-Ming; Cheng, Hsu-Chen; Ting, Chau-Ti; Li, Wen-Hsiung

    2016-08-01

    Birds can be classified into altricial and precocial. The hatchlings of altricial birds are almost naked, whereas those of precocial birds are covered with natal down. This regulatory divergence is thought to reflect environmental adaptation, but the molecular basis of the divergence is unclear. To address this issue, we chose the altricial zebra finch and the precocial chicken as the model animals. We noted that zebra finch hatchlings show natal down growth suppressed anterior dorsal (AD) skin but partially down-covered posterior dorsal (PD) skin. Comparing the transcriptomes of AD and PD skins, we found that the feather growth promoter SHH (sonic hedgehog) was expressed higher in PD skin than in AD skin. Moreover, the data suggested that the FGF (fibroblast growth factor)/Mitogen-activated protein kinase (MAPK) signaling pathway is involved in natal down growth suppression and that FGF16 is a candidate upstream signaling suppressor. Ectopic expression of FGF16 on chicken leg skin showed downregulation of SHH, upregulation of the feather growth suppressor FGF10, and suppression of feather bud elongation, similar to the phenotype found in zebra finch embryonic AD skin. Therefore, we propose that FGF16-related signals suppress natal down elongation and cause the naked AD skin in zebra finch. Our study provides insights into the regulatory divergence in natal down formation between precocial and altricial birds. PMID:27189543

  20. A Generalizability Analysis of Subjective Personality Assessments in the Stumptail Macaque and the Zebra Finch.

    ERIC Educational Resources Information Center

    Figueredo, Aurelio Jose; And Others

    1995-01-01

    Two longitudinal studies involving 29 raters concerning the construct validity, temporal stability, and interrater reliability of the latent common factors underlying subjective assessments by human raters of personality traits in the stumptail macaque and the zebra finch illustrate the use of generalizability analysis to test prespecified…

  1. The Quantitative Ethology of the Zebra Finch: A Study in Comparative Psychometrics.

    ERIC Educational Resources Information Center

    Figueredo, Aurelio Jose; And Others

    1992-01-01

    A quantitative ethogram was developed for the zebra finch, using one-zero focal animal sampling on an ethologically comprehensive checklist of 52 behavioral items, and it was assessed for interobserver reliability and construct validity. Applying the quantitative methods of psychometrics allows verification of ethological theory and testing of…

  2. Breeding Experience, Alternative Reproductive Strategies and Reproductive Success in a Captive Colony of Zebra Finches (Taeniopygia guttata)

    PubMed Central

    Baran, Nicole M.; Adkins-Regan, Elizabeth

    2014-01-01

    Birds exhibit a remarkable diversity of different reproductive strategies both between and within species. Species such as the zebra finch (Taeniopygia guttata) may evolve the flexible use of alternative reproductive strategies, as well as benefit from prior breeding experience, which allows them to adaptively respond to unpredictable environments. In birds, the flexible use of alternative reproductive strategies, such as extra-pair mating, has been reported to be associated with fast reproduction, high mortality and environmental variability. However, little is known about the role of previous breeding experience in the adaptive use of alternative reproductive strategies. Here we performed an in-depth study of reproductive outcomes in a population of domesticated zebra finches, testing the impact of prior breeding experience on the use of alternative reproductive strategies and reproductive success. We provide evidence that older females with prior breeding experience are quicker to initiate a clutch with a new partner and have increased success in chick rearing, even in a captive colony of zebra finches with minimal foraging demands. We also find evidence that the breeding experience of other females in the same social group influences reproductive investment by female zebra finches. Furthermore, we demonstrate that the use of alternative reproductive strategies in female zebra finches is associated with previous failed breeding attempts with the same pair partner. The results provide evidence that age and breeding experience play important roles in the flexible use of both facultative and adaptive reproductive strategies in female zebra finches. PMID:24587051

  3. Breeding experience, alternative reproductive strategies and reproductive success in a captive colony of zebra finches (Taeniopygia guttata).

    PubMed

    Baran, Nicole M; Adkins-Regan, Elizabeth

    2014-01-01

    Birds exhibit a remarkable diversity of different reproductive strategies both between and within species. Species such as the zebra finch (Taeniopygia guttata) may evolve the flexible use of alternative reproductive strategies, as well as benefit from prior breeding experience, which allows them to adaptively respond to unpredictable environments. In birds, the flexible use of alternative reproductive strategies, such as extra-pair mating, has been reported to be associated with fast reproduction, high mortality and environmental variability. However, little is known about the role of previous breeding experience in the adaptive use of alternative reproductive strategies. Here we performed an in-depth study of reproductive outcomes in a population of domesticated zebra finches, testing the impact of prior breeding experience on the use of alternative reproductive strategies and reproductive success. We provide evidence that older females with prior breeding experience are quicker to initiate a clutch with a new partner and have increased success in chick rearing, even in a captive colony of zebra finches with minimal foraging demands. We also find evidence that the breeding experience of other females in the same social group influences reproductive investment by female zebra finches. Furthermore, we demonstrate that the use of alternative reproductive strategies in female zebra finches is associated with previous failed breeding attempts with the same pair partner. The results provide evidence that age and breeding experience play important roles in the flexible use of both facultative and adaptive reproductive strategies in female zebra finches.

  4. Mitochondrial uncoupling as a regulator of life-history trajectories in birds: an experimental study in the zebra finch.

    PubMed

    Stier, Antoine; Bize, Pierre; Roussel, Damien; Schull, Quentin; Massemin, Sylvie; Criscuolo, François

    2014-10-01

    Mitochondria have a fundamental role in the transduction of energy from food into ATP. The coupling between food oxidation and ATP production is never perfect, but may nevertheless be of evolutionary significance. The 'uncoupling to survive' hypothesis suggests that 'mild' mitochondrial uncoupling evolved as a protective mechanism against the excessive production of damaging reactive oxygen species (ROS). Because resource allocation and ROS production are thought to shape animal life histories, alternative life-history trajectories might be driven by individual variation in the degree of mitochondrial uncoupling. We tested this hypothesis in a small bird species, the zebra finch (Taeniopygia guttata), by treating adults with the artificial mitochondrial uncoupler 2,4-dinitrophenol (DNP) over a 32-month period. In agreement with our expectations, the uncoupling treatment increased metabolic rate. However, we found no evidence that treated birds enjoyed lower oxidative stress levels or greater survival rates, in contrast to previous results in other taxa. In vitro experiments revealed lower sensitivity of ROS production to DNP in mitochondria isolated from skeletal muscles of zebra finch than mouse. In addition, we found significant reductions in the number of eggs laid and in the inflammatory immune response in treated birds. Altogether, our data suggest that the 'uncoupling to survive' hypothesis may not be applicable for zebra finches, presumably because of lower effects of mitochondrial uncoupling on mitochondrial ROS production in birds than in mammals. Nevertheless, mitochondrial uncoupling appeared to be a potential life-history regulator of traits such as fecundity and immunity at adulthood, even with food supplied ad libitum. PMID:25063856

  5. Mitochondrial uncoupling as a regulator of life-history trajectories in birds: an experimental study in the zebra finch.

    PubMed

    Stier, Antoine; Bize, Pierre; Roussel, Damien; Schull, Quentin; Massemin, Sylvie; Criscuolo, François

    2014-10-01

    Mitochondria have a fundamental role in the transduction of energy from food into ATP. The coupling between food oxidation and ATP production is never perfect, but may nevertheless be of evolutionary significance. The 'uncoupling to survive' hypothesis suggests that 'mild' mitochondrial uncoupling evolved as a protective mechanism against the excessive production of damaging reactive oxygen species (ROS). Because resource allocation and ROS production are thought to shape animal life histories, alternative life-history trajectories might be driven by individual variation in the degree of mitochondrial uncoupling. We tested this hypothesis in a small bird species, the zebra finch (Taeniopygia guttata), by treating adults with the artificial mitochondrial uncoupler 2,4-dinitrophenol (DNP) over a 32-month period. In agreement with our expectations, the uncoupling treatment increased metabolic rate. However, we found no evidence that treated birds enjoyed lower oxidative stress levels or greater survival rates, in contrast to previous results in other taxa. In vitro experiments revealed lower sensitivity of ROS production to DNP in mitochondria isolated from skeletal muscles of zebra finch than mouse. In addition, we found significant reductions in the number of eggs laid and in the inflammatory immune response in treated birds. Altogether, our data suggest that the 'uncoupling to survive' hypothesis may not be applicable for zebra finches, presumably because of lower effects of mitochondrial uncoupling on mitochondrial ROS production in birds than in mammals. Nevertheless, mitochondrial uncoupling appeared to be a potential life-history regulator of traits such as fecundity and immunity at adulthood, even with food supplied ad libitum.

  6. Time-dependent localization of high- and low-sulfated keratan sulfates in the song nuclei of developing zebra finches.

    PubMed

    Fujimoto, Hisataka; Ohgomori, Tomohiro; Abe, Kentaro; Uchimura, Kenji; Kadomatsu, Kenji; Jinno, Shozo

    2015-11-01

    Keratan sulfate proteoglycans (KSPGs) and chondroitin sulfate proteoglycans (CSPGs) consist of a protein core with covalently attached glycosaminoglycan side chain. Although CSPGs are known to regulate the end of the critical period, the role of KSPGs in brain development remains unclear. Young male zebra finches memorise song templates during development. The brain regions that are responsible for song learning, known as song nuclei, are recognized as a suitable model for the study of brain development. To understand the potential role of KSPGs, here we examined the localization of KSs with different degrees of sulfation in the brain of developing male zebra finches. Exclusively in the song nuclei, an increase in expression of 5-D-4-positive (5-D-4(+)) high-sulfated KS started after hatching, and reached a plateau at the end of the sensory period, during which the young bird listens to and memorises the song of an adult tutor. By contrast, weak and ubiquitous expression of BCD-4(+) low-sulfated KS remained unchanged until the end of the sensory period, and first increased in the song nuclei at the end of the sensorimotor period, during which the young bird produces plastic songs. Immunoblot analysis showed that phosphacan was a common core protein of 5-D-4(+) KS and BCD-4(+) KS. Finally, we confirmed that the sulfotransferase responsible for the synthesis of high-sulfated KS was exclusively localised in the song nuclei. Our observations suggest that time-dependent localization of KSPGs with different sulfation patterns in the song nuclei may underlie song learning in developing male zebra finches. PMID:26369722

  7. Early-Life Stress Triggers Juvenile Zebra Finches to Switch Social Learning Strategies

    PubMed Central

    Farine, Damien R.; Spencer, Karen A.; Boogert, Neeltje J.

    2015-01-01

    Summary Stress during early life can cause disease and cognitive impairment in humans and non-humans alike [1]. However, stress and other environmental factors can also program developmental pathways [2, 3]. We investigate whether differential exposure to developmental stress can drive divergent social learning strategies [4, 5] between siblings. In many species, juveniles acquire essential foraging skills by copying others: they can copy peers (horizontal social learning), learn from their parents (vertical social learning), or learn from other adults (oblique social learning) [6]. However, whether juveniles’ learning strategies are condition dependent largely remains a mystery. We found that juvenile zebra finches living in flocks socially learned novel foraging skills exclusively from adults. By experimentally manipulating developmental stress, we further show that social learning targets are phenotypically plastic. While control juveniles learned foraging skills from their parents, their siblings, exposed as nestlings to experimentally elevated stress hormone levels, learned exclusively from unrelated adults. Thus, early-life conditions triggered individuals to switch strategies from vertical to oblique social learning. This switch could arise from stress-induced differences in developmental rate, cognitive and physical state, or the use of stress as an environmental cue. Acquisition of alternative social learning strategies may impact juveniles’ fit to their environment and ultimately change their developmental trajectories. PMID:26212879

  8. Early-Life Stress Triggers Juvenile Zebra Finches to Switch Social Learning Strategies.

    PubMed

    Farine, Damien R; Spencer, Karen A; Boogert, Neeltje J

    2015-08-17

    Stress during early life can cause disease and cognitive impairment in humans and non-humans alike. However, stress and other environmental factors can also program developmental pathways. We investigate whether differential exposure to developmental stress can drive divergent social learning strategies between siblings. In many species, juveniles acquire essential foraging skills by copying others: they can copy peers (horizontal social learning), learn from their parents (vertical social learning), or learn from other adults (oblique social learning). However, whether juveniles' learning strategies are condition dependent largely remains a mystery. We found that juvenile zebra finches living in flocks socially learned novel foraging skills exclusively from adults. By experimentally manipulating developmental stress, we further show that social learning targets are phenotypically plastic. While control juveniles learned foraging skills from their parents, their siblings, exposed as nestlings to experimentally elevated stress hormone levels, learned exclusively from unrelated adults. Thus, early-life conditions triggered individuals to switch strategies from vertical to oblique social learning. This switch could arise from stress-induced differences in developmental rate, cognitive and physical state, or the use of stress as an environmental cue. Acquisition of alternative social learning strategies may impact juveniles' fit to their environment and ultimately change their developmental trajectories.

  9. No response to linear polarization cues in operant conditioning experiments with zebra finches.

    PubMed

    Melgar, Julian; Lind, Olle; Muheim, Rachel

    2015-07-01

    Many animals can use the polarization of light in various behavioural contexts. Birds are well known to use information from the skylight polarization pattern for orientation and compass calibration. However, there are few controlled studies of polarization vision in birds, and the majority of them have not been successful in convincingly demonstrating polarization vision. We used a two-alternative forced choice conditioning approach to assess linear polarization vision in male zebra finches in the 'visible' spectral range (wavelengths >400 nm). The birds were trained to discriminate colour, brightness and polarization stimuli presented on either one of two LCD-screens. All birds were able to discriminate the colour and brightness stimuli, but they were unable to discriminate the polarization stimuli. Our results suggest that in the behavioural context studied here, zebra finches are not able to discriminate polarized light stimuli.

  10. Flavoprotein Autofluorescence Imaging of Visual System Activity in Zebra Finches and Mice

    PubMed Central

    Michael, Neethu; Bischof, Hans-Joachim; Löwel, Siegrid

    2014-01-01

    Large-scale brain activity patterns can be visualized by optical imaging of intrinsic signals (OIS) based on activity-dependent changes in the blood oxygenation level. Another method, flavoprotein autofluorescence imaging (AFI), exploits the mitochondrial flavoprotein autofluorescence, which is enhanced during neuronal activity. In birds, topographic mapping of visual space has been shown in the visual wulst, the avian homologue of the mammalian visual cortex by using OIS. We here applied the AFI method to visualize topographic maps in the visual wulst because with OIS, which depends on blood flow changes, blood vessel artifacts often obscure brain activity maps. We then compared both techniques quantitatively in zebra finches and in C57Bl/6J mice using the same setup and stimulation conditions. In addition to experiments with craniotomized animals, we also examined mice with intact skull (in zebra finches, intact skull imaging is not feasible probably due to the skull construction). In craniotomized animals, retinotopic maps were obtained by both methods in both species. Using AFI, artifacts caused by blood vessels were generally reduced, the magnitude of neuronal activity significantly higher and the retinotopic map quality better than that obtained by OIS in both zebra finches and mice. In contrast, our measurements in non-craniotomized mice did not reveal any quantitative differences between the two methods. Our results thus suggest that AFI is the method of choice for investigations of visual processing in zebra finches. In mice, however, if researchers decide to use the advantages of imaging through the intact skull, they will not be able to exploit the higher signals obtainable by the AFI-method. PMID:24400130

  11. Noninvasive diffusive optical imaging of the auditory response to birdsong in the zebra finch.

    PubMed

    Lee, James V; Maclin, Edward L; Low, Kathy A; Gratton, Gabriele; Fabiani, Monica; Clayton, David F

    2013-03-01

    Songbirds communicate by learned vocalizations with concomitant changes in neurophysiological and genomic activities in discrete parts of the brain. Here, we tested a novel implementation of diffusive optical imaging (also known as diffuse optical imaging, DOI) for monitoring brain physiology associated with vocal signal perception. DOI noninvasively measures brain activity using red and near-infrared light delivered through optic fibers (optodes) resting on the scalp. DOI does not harm subjects, so it raises the possibility of repeatedly measuring brain activity and the effects of accumulated experience in the same subject over an entire life span, all while leaving tissue intact for further study. We developed a custom-made apparatus for interfacing optodes to the zebra finch (Taeniopygia guttata) head using 3D modeling software and rapid prototyping technology, and applied it to record responses to presentations of birdsong in isoflurane-anesthetized zebra finches. We discovered a subtle but significant difference between the hemoglobin spectra of zebra finches and mammals which has a major impact in how hemodynamic responses are interpreted in the zebra finch. Our measured responses to birdsong playback were robust, highly repeatable, and readily observed in single trials. Responses were complex in shape and closely paralleled responses described in mammals. They were localized to the caudal medial portion of the brain, consistent with response localization from prior gene expression, electrophysiological, and functional magnetic resonance imaging studies. These results define an approach for collecting neurophysiological data from songbirds that should be applicable to diverse species and adaptable for studies in awake behaving animals. PMID:23322445

  12. Noninvasive diffusive optical imaging of the auditory response to birdsong in the zebra finch

    PubMed Central

    Lee, James V.; Maclin, Edward L.; Low, Kathy A.; Gratton, Gabriele; Fabiani, Monica; Clayton, David F.

    2013-01-01

    Songbirds communicate by learned vocalizations with concomitant changes in neurophysiological and genomic activities in discrete parts of the brain. Here we tested a novel implementation of diffusive optical imaging (also known as diffuse optical imaging, DOI) for monitoring brain physiology associated with vocal signal perception. DOI noninvasively measures brain activity using red and near-infrared light delivered through optic fibers (optodes) resting on the scalp. DOI does not harm subjects, so it raises the possibility of repeatedly measuring brain activity and the effects of accumulated experience in the same subject over an entire life span, all while leaving tissue intact for further study. We developed a custom-made apparatus for interfacing optodes to the zebra finch (Taeniopygia guttata) head using 3D modeling software and rapid prototyping technology, and applied it to record responses to presentations of birdsong in isoflurane-anesthetized zebra finches. We discovered a subtle but significant difference between the hemoglobin spectra of zebra finches and mammals which has a major impact in how hemodynamic responses are interpreted in the zebra finch. Our measured responses to birdsong playback were robust, highly repeatable, and readily observed in single trials. Responses were complex in shape and closely paralleled responses described in mammals. They were localized to the caudal medial portion of the brain, consistent with response localization from prior gene expression, electrophysiological, and functional magnetic resonance imaging studies. These results define an approach for collecting neurophysiological data from songbirds that should be applicable to diverse species and adaptable for studies in awake behaving animals. PMID:23322445

  13. Zebra Finch Mates Use Their Forebrain Song System in Unlearned Call Communication

    PubMed Central

    Ter Maat, Andries; Trost, Lisa; Sagunsky, Hannes; Seltmann, Susanne; Gahr, Manfred

    2014-01-01

    Unlearned calls are produced by all birds whereas learned songs are only found in three avian taxa, most notably in songbirds. The neural basis for song learning and production is formed by interconnected song nuclei: the song control system. In addition to song, zebra finches produce large numbers of soft, unlearned calls, among which “stack” calls are uttered frequently. To determine unequivocally the calls produced by each member of a group, we mounted miniature wireless microphones on each zebra finch. We find that group living paired males and females communicate using bilateral stack calling. To investigate the role of the song control system in call-based male female communication, we recorded the electrical activity in a premotor nucleus of the song control system in freely behaving male birds. The unique combination of acoustic monitoring together with wireless brain recording of individual zebra finches in groups shows that the neuronal activity of the song system correlates with the production of unlearned stack calls. The results suggest that the song system evolved from a brain circuit controlling simple unlearned calls to a system capable of producing acoustically rich, learned vocalizations. PMID:25313846

  14. Bill Redness Is Positively Associated with Reproduction and Survival in Male and Female Zebra Finches

    PubMed Central

    Simons, Mirre J. P.; Briga, Michael; Koetsier, Egbert; Folkertsma, Remco; Wubs, Matthias D.; Dijkstra, Cor; Verhulst, Simon

    2012-01-01

    Sexual traits can serve as honest indicators of phenotypic quality when they are costly. Brightly coloured yellow to red traits, which are pigmented by carotenoids, are relatively common in birds, and feature in sexual selection. Carotenoids have been linked to immune and antioxidant function, and the trade-off between ornamentation and these physiological functions provides a potential mechanism rendering carotenoid based signals costly. Mutual ornamentation is also common in birds and can be maintained by mutual mate choice for this ornament or by a correlated response in one sex to selection on the other sex. When selection pressures differ between the sexes this can cause intralocus sexual conflict. Sexually antagonistic selection pressures have been demonstrated for few sexual traits, and for carotenoid-dependent traits there is a single example: bill redness was found to be positively associated with survival and reproductive output in male zebra finches, but negatively so in females. We retested these associations in our captive zebra finch population without two possible limitations of this earlier study. Contrary to the earlier findings, we found no evidence for sexually antagonistic selection. In both sexes, individuals with redder bills showed higher survival. This association disappeared among the females with the reddest bills. Furthermore, females with redder bills achieved higher reproductive output. We conclude that bill redness of male and female zebra finches honestly signals phenotypic quality, and discuss the possible causes of the differences between our results and earlier findings. PMID:22808243

  15. Social facilitation of male song by male and female conspecifics in the zebra finch, Taeniopygia guttata.

    PubMed

    Jesse, Fabienne; Riebel, Katharina

    2012-11-01

    Zebra finches are a ubiquitous model system for the study of vocal learning in animal communication. Their song has been well described, but its possible function(s) in social communication are only partly understood. The so-called 'directed song' is a high-intensity, high-performance song given during courtship in close proximity to the female, which is known to mediate mate choice and mating. However, this singing mode constitutes only a fraction of zebra finch males' prolific song output. Potential communicative functions of their second, 'undirected' singing mode remain unresolved in the face of contradicting reports of both facilitating and inhibiting effects of social company on singing. We addressed this issue by experimentally manipulating social contexts in a within-subject design, comparing a solo versus male or female only company condition, each lasting for 24h. Males' total song output was significantly higher when a conspecific was in audible and visible distance than when they were alone. Male and female company had an equally facilitating effect on song output. Our findings thus indicate that singing motivation is facilitated rather than inhibited by social company, suggesting that singing in zebra finches might function both in inter- and intrasexual communication.

  16. Social facilitation of male song by male and female conspecifics in the zebra finch, Taeniopygia guttata.

    PubMed

    Jesse, Fabienne; Riebel, Katharina

    2012-11-01

    Zebra finches are a ubiquitous model system for the study of vocal learning in animal communication. Their song has been well described, but its possible function(s) in social communication are only partly understood. The so-called 'directed song' is a high-intensity, high-performance song given during courtship in close proximity to the female, which is known to mediate mate choice and mating. However, this singing mode constitutes only a fraction of zebra finch males' prolific song output. Potential communicative functions of their second, 'undirected' singing mode remain unresolved in the face of contradicting reports of both facilitating and inhibiting effects of social company on singing. We addressed this issue by experimentally manipulating social contexts in a within-subject design, comparing a solo versus male or female only company condition, each lasting for 24h. Males' total song output was significantly higher when a conspecific was in audible and visible distance than when they were alone. Male and female company had an equally facilitating effect on song output. Our findings thus indicate that singing motivation is facilitated rather than inhibited by social company, suggesting that singing in zebra finches might function both in inter- and intrasexual communication. PMID:23026146

  17. HTR2 Receptors in a Songbird Premotor Cortical-Like Area Modulate Spectral Characteristics of Zebra Finch Song

    PubMed Central

    Wood, William E.; Roseberry, Thomas K.; Perkel, David J.

    2013-01-01

    Serotonin [5-hydroxytryptamine (5-HT)] is involved in modulating an array of complex behaviors including learning, depression, and circadian rhythms. Additionally, HTR2 receptors on layer V pyramidal neurons are thought to mediate the actions of psychedelic drugs; the native function of these receptors at this site, however, remains unknown. Previously, we found that activation of HTR2 receptors in the zebra finch forebrain song premotor structure the robust nucleus of the arcopallium (RA) led to increased excitation, and that endogenous 5-HT could roughly double spontaneous firing rate. Here, using in vivo single-unit recordings, we found that direct application of 5-HT to these same RA projection neurons, which are analogous to layer V cortical pyramidal neurons, caused a significant increase in the number of action potentials per song-related burst, and a dramatic decrease in signal-to-noise ratio. Injection of the serotonergic neurotoxin 5,7-dihydroxytryptamine into the third ventricle greatly reduced telencephalic 5-HT and resulted in decreased fundamental frequency of harmonic syllables as well as increased goodness of pitch. Both of these results can be explained by the observed actions of 5-HT on RA projection neurons, and both effects recovered to baseline within 2 weeks following the toxin injection. These results show that 5-HT is involved in modulating spectral properties of song, likely via effects on RA projection neurons, but that adult zebra finches can partially compensate for this deficit within 7 d. PMID:23407949

  18. Acoustic pattern variations in the female-directed birdsongs of a colony of laboratory-bred zebra finches.

    PubMed

    Helekar; Marsh; Viswanath; Rosenfield

    2000-04-01

    The acoustic profile of the zebra finch song is characterized by a series of identical repeating units, each comprising a distinctive sequence of acoustic elements, called syllables. Here, we perform an analysis of song pattern deviations caused by variabilities in the production of song syllables. Zebra finches produce four different kinds of syllable variabilities-syllable deletions, single or double syllable insertions, syllable alterations, and syllable repetitions. All these variabilities, with the exception of repetitions, are present in songs of more than two-thirds of the normal adult birds; repetitions are present in less than one-fifth of birds. The frequency of occurrence of these variabilities is independent of the amount of singing, suggesting that they are unlikely to result simply from singing-induced physiological changes such as fatigue. Their frequencies in tutor-deprived birds are not significantly different from those in normal birds, indicating that they are unlikely to be acquired due to deficiencies in tutor-dependent learning. The types, patterns of occurrence and relative frequencies of these song syllable variabilities might reveal insights into the functioning of the song motor control pathway.

  19. Acoustic pattern variations in the female-directed birdsongs of a colony of laboratory-bred zebra finches.

    PubMed

    Helekar; Marsh; Viswanath; Rosenfield

    2000-04-01

    The acoustic profile of the zebra finch song is characterized by a series of identical repeating units, each comprising a distinctive sequence of acoustic elements, called syllables. Here, we perform an analysis of song pattern deviations caused by variabilities in the production of song syllables. Zebra finches produce four different kinds of syllable variabilities-syllable deletions, single or double syllable insertions, syllable alterations, and syllable repetitions. All these variabilities, with the exception of repetitions, are present in songs of more than two-thirds of the normal adult birds; repetitions are present in less than one-fifth of birds. The frequency of occurrence of these variabilities is independent of the amount of singing, suggesting that they are unlikely to result simply from singing-induced physiological changes such as fatigue. Their frequencies in tutor-deprived birds are not significantly different from those in normal birds, indicating that they are unlikely to be acquired due to deficiencies in tutor-dependent learning. The types, patterns of occurrence and relative frequencies of these song syllable variabilities might reveal insights into the functioning of the song motor control pathway. PMID:10794919

  20. HTR2 receptors in a songbird premotor cortical-like area modulate spectral characteristics of zebra finch song.

    PubMed

    Wood, William E; Roseberry, Thomas K; Perkel, David J

    2013-02-13

    Serotonin [5-hydroxytryptamine (5-HT)] is involved in modulating an array of complex behaviors including learning, depression, and circadian rhythms. Additionally, HTR2 receptors on layer V pyramidal neurons are thought to mediate the actions of psychedelic drugs; the native function of these receptors at this site, however, remains unknown. Previously, we found that activation of HTR2 receptors in the zebra finch forebrain song premotor structure the robust nucleus of the arcopallium (RA) led to increased excitation, and that endogenous 5-HT could roughly double spontaneous firing rate. Here, using in vivo single-unit recordings, we found that direct application of 5-HT to these same RA projection neurons, which are analogous to layer V cortical pyramidal neurons, caused a significant increase in the number of action potentials per song-related burst, and a dramatic decrease in signal-to-noise ratio. Injection of the serotonergic neurotoxin 5,7-dihydroxytryptamine into the third ventricle greatly reduced telencephalic 5-HT and resulted in decreased fundamental frequency of harmonic syllables as well as increased goodness of pitch. Both of these results can be explained by the observed actions of 5-HT on RA projection neurons, and both effects recovered to baseline within 2 weeks following the toxin injection. These results show that 5-HT is involved in modulating spectral properties of song, likely via effects on RA projection neurons, but that adult zebra finches can partially compensate for this deficit within 7 d. PMID:23407949

  1. Discovery of a novel functional leptin protein (LEP) in zebra finches: evidence for the existence of an authentic avian leptin gene predominantly expressed in the brain and pituitary.

    PubMed

    Huang, Guian; Li, Juan; Wang, Hongning; Lan, Xinyu; Wang, Yajun

    2014-09-01

    Leptin (LEP) is reported to play important roles in controlling energy balance in vertebrates, including birds. However, it remains an open question whether an authentic "LEP gene" exists and functions in birds. Here, we identified and characterized a LEP gene (zebra finch LEP [zbLEP]) encoding a 172-amino acid precursor in zebra finches. Despite zbLEP showing limited amino acid sequence identity (26%-29%) to human and mouse LEPs, synteny analysis proved that zbLEP is orthologous to mammalian LEP. Using a pAH32 luciferase reporter system and Western blot analysis, we demonstrated that the recombinant zbLEP protein could potently activate finch and chicken LEP receptors (zbLEPR; cLEPR) expressed in human embryonic kidney 293 cells and enhance signal transducer and activator of transcription 3 phosphorylation, further indicating that zbLEP is a functional ligand for avian LEPRs. Interestingly, quantitative real-time RT-PCR revealed that zbLEP mRNA is expressed nearly exclusively in the pituitary and various brain regions but undetectable in adipose tissue and liver, whereas zbLEPR mRNA is widely expressed in adult finch tissues examined with abundant expression noted in pituitary, implying that unlike mammalian LEP, finch LEP may not act as an adipocyte-derived signal to control energy balance. As in finches, a LEP highly homologous to zbLEP was also identified in budgerigar genome. Strikingly, finch and budgerigar LEPs show little homology with chicken LEP (cLEP) previously reported, suggesting that the so-called cLEP is incorrect. Collectively, our data provide convincing evidence for the existence of an authentic functional LEP in avian species and suggest an important role of brain- and pituitary-derived LEP played in vertebrates.

  2. Developmental exposure to a brominated flame retardant: an assessment of effects on physiology, growth, and reproduction in a songbird, the zebra finch.

    PubMed

    Eng, Margaret L; Williams, Tony D; Elliott, John E

    2013-07-01

    Mixtures of polybrominated diphenyl ethers (PBDEs) have been widely used as additive flame retardants, and BDE-99 is one of the most predominant congeners found in the environment. BDE-99 has been reported in avian samples worldwide, yet knowledge of its toxicity to birds is minimal. We assessed the short- and long-term effects of nestling exposure to environmentally relevant levels of BDE-99 in a model passerine, the zebra finch. Early exposure to BDE-99 did not affect hematocrit, oxidative stress, or thyroid hormones in either the juvenile or adult stages, and there were no effects on chick growth or survival. BDE-99 exposure caused a dose-dependent delay in timing of reproduction, but there were no other effects on reproductive success. In zebra finches, endpoints related to reproductive behavior appear to be the most sensitive to BDE-99. However, passerines overall appear to be less sensitive than birds of prey or mammals to PBDE exposure. PMID:23603472

  3. Maternal antibody transfer can lead to suppression of humoral immunity in developing zebra finches (Taeniopygia guttata).

    PubMed

    Merrill, Loren; Grindstaff, Jennifer L

    2014-01-01

    Maternally transferred antibodies have been documented in a wide range of taxa and are thought to adaptively provide protection against parasites and pathogens while the offspring immune system is developing. In most birds, transfer occurs when females deposit immunoglobulin Y into the egg yolk, and it is proportional to the amount in the female's plasma. Maternal antibodies can provide short-term passive protection as well as specific and nonspecific immunological priming, but high levels of maternal antibody can result in suppression of the offspring's humoral immune response. We injected adult female zebra finches (Taeniopygia guttata) with one of two antigens (lipopolysaccharide [LPS] or keyhole limpet hemocyanin [KLH]) or a control and then injected offspring with LPS, KLH, or a control on days 5 and 28 posthatch to examine the impact of maternally transferred antibodies on the ontogeny of the offspring's humoral immune system. We found that offspring of females exposed to KLH had elevated levels of KLH-reactive antibody over the first 17-28 days posthatch but reduced KLH-specific antibody production between days 28 and 36. We also found that offspring exposed to either LPS or KLH exhibited reduced total antibody levels, compared to offspring that received a control injection. These results indicate that high levels of maternal antibodies or antigen exposure during development can have negative repercussions on short-term antibody production and may have long-term fitness repercussions for the offspring.

  4. Metabolic and Respiratory Costs of Increasing Song Amplitude in Zebra Finches

    PubMed Central

    Zollinger, Sue Anne; Goller, Franz; Brumm, Henrik

    2011-01-01

    Bird song is a widely used model in the study of animal communication and sexual selection, and several song features have been shown to reflect the quality of the singer. Recent studies have demonstrated that song amplitude may be an honest signal of current condition in males and that females prefer high amplitude songs. In addition, birds raise the amplitude of their songs to communicate in noisy environments. Although it is generally assumed that louder song should be more costly to produce, there has been little empirical evidence to support this assumption. We tested the assumption by measuring oxygen consumption and respiratory patterns in adult male zebra finches (Taeniopygia guttata) singing at different amplitudes in different background noise conditions. As background noise levels increased, birds significantly increased the sound pressure level of their songs. We found that louder songs required significantly greater subsyringeal air sac pressure than quieter songs. Though increased pressure is probably achieved by increasing respiratory muscle activity, these increases did not correlate with measurable increases in oxygen consumption. In addition, we found that oxygen consumption increased in higher background noise, independent of singing behaviour. This observation supports previous research in mammals showing that high levels of environmental noise can induce physiological stress responses. While our study did not find that increasing vocal amplitude increased metabolic costs, further research is needed to determine whether there are other non-metabolic costs of singing louder or costs associated with chronic noise exposure. PMID:21915258

  5. Differential coexpression of FoxP1, FoxP2, and FoxP4 in the Zebra Finch (Taeniopygia guttata) song system.

    PubMed

    Mendoza, Ezequiel; Tokarev, Kirill; Düring, Daniel N; Retamosa, Eva Camarillo; Weiss, Michael; Arpenik, Nshdejan; Scharff, Constance

    2015-06-15

    Heterozygous disruptions of the Forkhead transcription factor FoxP2 impair acquisition of speech and language. Experimental downregulation in brain region Area X of the avian ortholog FoxP2 disrupts song learning in juvenile male zebra finches. In vitro, transcriptional activity of FoxP2 requires dimerization with itself or with paralogs FoxP1 and FoxP4. Whether this is the case in vivo is unknown. To provide the means for future functional studies we cloned FoxP4 from zebra finches and compared regional and cellular coexpression of FoxP1, FoxP2, and FoxP4 mRNA and protein in brains of juvenile and adult male zebra finches. In the telencephalic song nuclei HVC, RA, and Area X, the three investigated FoxPs were either expressed alone or occurred in specific combinations with each other, as shown by double in situ hybridization and triple immunohistochemistry. FoxP1 and FoxP4 but not FoxP2 were expressed in RA and in the HVCRA and HVCX projection neurons. In Area X and the surrounding striatum the density of neurons expressing all three FoxPs together or FoxP1 and FoxP4 together was significantly higher than the density of neurons expressing other combinations. Interestingly, the proportions of Area X neurons expressing particular combinations of FoxPs remained constant at all ages. In addition, FoxP-expressing neurons in adult Area X express dopamine receptors 1A, 1B, and 2. Together, these data provide the first evidence that Area X neurons can coexpress all avian FoxP subfamily members, thus allowing for a variety of regulatory possibilities via heterodimerization that could impact song behavior in zebra finches.

  6. Using Digital Images of the Zebra Finch Song System as a Tool to Teach Organizational Effects of Steroid Hormones: A Free Downloadable Module

    ERIC Educational Resources Information Center

    Grisham, William; Schottler, Natalie A.; Beck McCauley, Lisa M.; Pham, Anh P.; Ruiz, Maureen L.; Fong, Michelle C.; Cui, Xinran

    2011-01-01

    Zebra finch song behavior is sexually dimorphic: males sing and females do not. The neural system underlying this behavior is sexually dimorphic, and this sex difference is easy to quantify. During development, the zebra finch song system can be altered by steroid hormones, specifically estradiol, which actually masculinizes it. Because of the…

  7. Oscillating magnetic field disrupts magnetic orientation in Zebra finches, Taeniopygia guttata

    PubMed Central

    Keary, Nina; Ruploh, Tim; Voss, Joe; Thalau, Peter; Wiltschko, Roswitha; Wiltschko, Wolfgang; Bischof, Hans-Joachim

    2009-01-01

    Background Zebra finches can be trained to use the geomagnetic field as a directional cue for short distance orientation. The physical mechanisms underlying the primary processes of magnetoreception are, however, largely unknown. Two hypotheses of how birds perceive magnetic information are mainly discussed, one dealing with modulation of radical pair processes in retinal structures, the other assuming that iron deposits in the upper beak of the birds are involved. Oscillating magnetic fields in the MHz range disturb radical pair mechanisms but do not affect magnetic particles. Thus, application of such oscillating fields in behavioral experiments can be used as a diagnostic tool to decide between the two alternatives. Methods In a setup that eliminates all directional cues except the geomagnetic field zebra finches were trained to search for food in the magnetic north/south axis. The birds were then tested for orientation performance in two magnetic conditions. In condition 1 the horizontal component of the geomagnetic field was shifted by 90 degrees using a helmholtz coil. In condition 2 a high frequently oscillating field (1.156 MHz) was applied in addition to the shifted field. Another group of birds was trained to solve the orientation task, but with visual landmarks as directional cue. The birds were then tested for their orientation performance in the same magnetic conditions as applied for the first experiment. Results The zebra finches could be trained successfully to orient in the geomagnetic field for food search in the north/south axis. They were also well oriented in test condition 1, with the magnetic field shifted horizontally by 90 degrees. In contrast, when the oscillating field was added, the directional choices during food search were randomly distributed. Birds that were trained to visually guided orientation showed no difference of orientation performance in the two magnetic conditions. Conclusion The results indicate that zebra finches use a

  8. Knockdown of FoxP2 alters spine density in Area X of the zebra finch.

    PubMed

    Schulz, S B; Haesler, S; Scharff, C; Rochefort, C

    2010-10-01

    Mutations in the gene encoding the transcription factor FoxP2 impair human speech and language. We have previously shown that deficits in vocal learning occur in zebra finches after reduction of FoxP2 in Area X, a striatal nucleus involved in song acquisition. We recently showed that FoxP2 is expressed in newly generated spiny neurons (SN) in adult Area X as well as in the ventricular zone (VZ) from which the SN originates. Moreover, their recruitment to Area X increases transiently during the song learning phase. The present report therefore investigated whether FoxP2 is involved in the structural plasticity of Area X. We assessed the proliferation, differentiation and morphology of SN after lentivirally mediated knockdown of FoxP2 in Area X or in the VZ during the song learning phase. Proliferation rate was not significantly affected by knockdown of FoxP2 in the VZ. In addition, FoxP2 reduction both in the VZ and in Area X did not affect the number of new neurons in Area X. However, at the fine-structural level, SN in Area X bore fewer spines after FoxP2 knockdown. This effect was even more pronounced when neurons received the knockdown before differentiation, i.e. as neuroblasts in the VZ. These results suggest that FoxP2 might directly or indirectly regulate spine dynamics in Area X and thereby influence song plasticity. Together, these data present the first evidence for a role of FoxP2 in the structural plasticity of dendritic spines and complement the emerging evidence of physiological synaptic plasticity in FoxP2 mouse models.

  9. Pauses enhance chunk recognition in song element strings by zebra finches.

    PubMed

    Spierings, Michelle; de Weger, Anouk; Ten Cate, Carel

    2015-07-01

    When learning a language, it is crucial to know which syllables of a continuous sound string belong together as words. Human infants achieve this by attending to pauses between words or to the co-occurrence of syllables. It is not only humans that can segment a continuous string. Songbirds learning their song tend to copy 'chunks' from one or more tutors' songs and combine these into their own song. In the tutor songs, these chunks are often separated by pauses and a high co-occurrence of elements, suggesting that these features affect chunking and song learning. We examined experimentally whether the presence of pauses and element co-occurrence affect the ability of adult zebra finches to discriminate strings of song elements. Using a go/no-go design, two groups of birds were trained to discriminate between two strings. In one group (Pause-group), pauses were inserted between co-occurring element triplets in the strings, and in the other group (No-pause group), both strings were continuous. After making a correct discrimination, an individual proceeded to a reversal training using string segments. Segments were element triplets consistent in co-occurrence, triplets that were partly consistent in composition and triplets consisting of elements that did not co-occur in the strings. The Pause-group was faster in discriminating between the two strings. This group also responded differently to consistent triplets in the reversal training, compared to inconsistent triplets. The No-pause group did not differentiate among the triplet types. These results indicate that pauses in strings of song elements aid song discrimination and memorization of co-occurring element groups. PMID:25771964

  10. Brain activation pattern depends on the strategy chosen by zebra finches to solve an orientation task.

    PubMed

    Mayer, Uwe; Bischof, Hans-Joachim

    2012-02-01

    Zebra finches (Taeniopygia guttata) were trained to find food in one of four feeders on the floor of an aviary. This feeder was always in the same place during training and was additionally marked by a distinct pattern. In the test trial the distinctly patterned feeder was interchanged with one of the other feeders, so that the birds had to decide to use either the pattern or the original location for finding food. Half of the birds used one strategy and half used the other. According to the strategy applied, different brain areas were activated, as demonstrated by c-Fos immunohistochemistry. The hippocampus was activated when spatial cues were used, while in birds orienting using the pattern of the feeder, part of the collothalamic (tectofugal) visual system showed stronger activation. The visual wulst of the lemnothalamic (thalamofugal) visual system was activated with both strategies, indicating an involvement in both spatial and pattern-directed orientation. Because the experimental situation was the same for all zebra finches, the activation pattern was only dependent on the strategy that was voluntarily chosen by each of the birds.

  11. Zebra finches can use positional and transitional cues to distinguish vocal element strings.

    PubMed

    Chen, Jiani; Ten Cate, Carel

    2015-08-01

    Learning sequences is of great importance to humans and non-human animals. Many motor and mental actions, such as singing in birds and speech processing in humans, rely on sequential learning. At least two mechanisms are considered to be involved in such learning. The chaining theory proposes that learning of sequences relies on memorizing the transitions between adjacent items, while the positional theory suggests that learners encode the items according to their ordinal position in the sequence. Positional learning is assumed to dominate sequential learning. However, human infants exposed to a string of speech sounds can learn transitional (chaining) cues. So far, it is not clear whether birds, an increasingly important model for examining vocal processing, can do this. In this study we use a Go-Nogo design to examine whether zebra finches can use transitional cues to distinguish artificially constructed strings of song elements. Zebra finches were trained with sequences differing in transitional and positional information and next tested with novel strings sharing positional and transitional similarities with the training strings. The results show that they can attend to both transitional and positional cues and that their sequential coding strategies can be biased toward transitional cues depending on the learning context. This article is part of a Special Issue entitled: In Honor of Jerry Hogan. PMID:25217867

  12. Digital Atlas of the Zebra Finch (Taeniopygia guttata) Brain: a High Resolution Photo Atlas

    PubMed Central

    Karten, Harvey J.; Brzozowska-Prechtl, Agnieszka; Lovell, Peter V.; Tang, Daniel D.; Mello, Claudio V.; Wang, Haibin; Mitra, Partha P.

    2014-01-01

    We describe a set of new comprehensive, high-quality, high-resolution digital images of histological sections from the brain of male zebra finches (Taeniopygia guttata), and make them publicly available through an interactive website (http://zebrafinch.brainarchitecture.org/). These images provide a basis for the production of a dimensionally accurate and detailed digital non-stereotaxic atlas. Nissl- and myelin-stained brain sections are provided in the transverse, sagittal, and horizontal planes, with the transverse plane approximating the more traditional Frankfurt Plane. In addition, a separate set of brain sections in this same plane is stained for tyrosine hydroxylase, revealing the distribution of catecholaminergic neurons (dopaminergic, noradrenergic, and adrenergic) in the songbird brain. For a subset of sagittal sections we have also prepared a corresponding set of drawings, defining and annotating various nuclei, fields, and fiber tracts that are visible under Nissl and myelin staining. This atlas of the zebra finch brain is expected to become an important tool for birdsong research and comparative studies of brain organization and evolution. PMID:23896990

  13. Budgerigars and zebra finches differ in how they generalize in an artificial grammar learning experiment

    PubMed Central

    Spierings, Michelle J.; ten Cate, Carel

    2016-01-01

    The ability to abstract a regularity that underlies strings of sounds is a core mechanism of the language faculty but might not be specific to language learning or even to humans. It is unclear whether and to what extent nonhuman animals possess the ability to abstract regularities defining the relation among arbitrary auditory items in a string and to generalize this abstraction to strings of acoustically novel items. In this study we tested these abilities in a songbird (zebra finch) and a parrot species (budgerigar). Subjects were trained in a go/no-go design to discriminate between two sets of sound strings arranged in an XYX or an XXY structure. After this discrimination was acquired, each subject was tested with test strings that were structurally identical to the training strings but consisted of either new combinations of known elements or of novel elements belonging to other element categories. Both species learned to discriminate between the two stimulus sets. However, their responses to the test strings were strikingly different. Zebra finches categorized test stimuli with previously heard elements by the ordinal position that these elements occupied in the training strings, independent of string structure. In contrast, the budgerigars categorized both novel combinations of familiar elements as well as strings consisting of novel element types by their underlying structure. They thus abstracted the relation among items in the XYX and XXY structures, an ability similar to that shown by human infants and indicating a level of abstraction comparable to analogical reasoning. PMID:27325756

  14. Budgerigars and zebra finches differ in how they generalize in an artificial grammar learning experiment.

    PubMed

    Spierings, Michelle J; Ten Cate, Carel

    2016-07-01

    The ability to abstract a regularity that underlies strings of sounds is a core mechanism of the language faculty but might not be specific to language learning or even to humans. It is unclear whether and to what extent nonhuman animals possess the ability to abstract regularities defining the relation among arbitrary auditory items in a string and to generalize this abstraction to strings of acoustically novel items. In this study we tested these abilities in a songbird (zebra finch) and a parrot species (budgerigar). Subjects were trained in a go/no-go design to discriminate between two sets of sound strings arranged in an XYX or an XXY structure. After this discrimination was acquired, each subject was tested with test strings that were structurally identical to the training strings but consisted of either new combinations of known elements or of novel elements belonging to other element categories. Both species learned to discriminate between the two stimulus sets. However, their responses to the test strings were strikingly different. Zebra finches categorized test stimuli with previously heard elements by the ordinal position that these elements occupied in the training strings, independent of string structure. In contrast, the budgerigars categorized both novel combinations of familiar elements as well as strings consisting of novel element types by their underlying structure. They thus abstracted the relation among items in the XYX and XXY structures, an ability similar to that shown by human infants and indicating a level of abstraction comparable to analogical reasoning.

  15. In Vivo Recording of Single-Unit Activity during Singing in Zebra Finches

    PubMed Central

    Okubo, Tatsuo S.; Mackevicius, Emily L.; Fee, Michale S.

    2015-01-01

    The zebra finch is an important model for investigating the neural mechanisms that underlie vocal production and learning. Previous anatomical and gene expression studies have identified an interconnected set of brain areas in this organism that are important for singing. To advance our understanding of how these various brain areas act together to learn and produce a highly stereotyped song, it is necessary to record the activity of individual neurons during singing. Here, we present a protocol for recording single-unit activity in freely moving zebra finches during singing using a miniature, motorized microdrive. It includes procedures for both the microdrive implant surgery and the electrophysiological recordings. There are several advantages of this technique: (1) high-impedance electrodes can be used in the microdrive to obtain well-isolated single units; (2) a motorized microdrive is used to remotely control the electrode position, allowing neurons to be isolated without handling the bird, and (3) a lateral positioner is used to move electrodes into fresh tissue before each penetration, allowing recordings from well-isolated neurons over the course of several weeks. We also describe the application of the antidromic stimulation and the spike collision test to identify neurons based on the axonal projection patterns. PMID:25342072

  16. Female but not male zebra finches adjust heat output in response to increased incubation demand.

    PubMed

    Hill, Davina L; Lindström, Jan; McCafferty, Dominic J; Nager, Ruedi G

    2014-04-15

    In many incubating birds, heat transfer from parent to egg is facilitated by the brood patch, an area of ventral abdominal skin that becomes highly vascularised, swells and loses its down feathers around the time of laying. Only the female develops a brood patch in most passerine species, but males of some species can incubate and maintain the eggs at similar temperatures to females even without a brood patch. Here we used a novel application of infrared thermography to examine sex differences in parental care from a physiological perspective. Using incubating male and female zebra finches (Taeniopygia guttata), a species in which the male lacks a brood patch, we measured the surface temperature of the ventral plumage overlying the abdomen and a reference area that does not contact the eggs (thorax) twice per pair. In half of the pairs, clutch size was experimentally enlarged between the two sets of measurements to increase incubation demand. We found that the temperature differential between abdomen and thorax plumage was greater in females than in males, and that abdomen plumage was warmer after clutch enlargement than before in females but not in males. These findings are consistent with morphological sex differences in brood patch development and suggest that male and female zebra finches differ in the way they regulate abdomen versus general body surface temperature in response to variation in incubation demand.

  17. Zebra finches can use positional and transitional cues to distinguish vocal element strings.

    PubMed

    Chen, Jiani; Ten Cate, Carel

    2015-08-01

    Learning sequences is of great importance to humans and non-human animals. Many motor and mental actions, such as singing in birds and speech processing in humans, rely on sequential learning. At least two mechanisms are considered to be involved in such learning. The chaining theory proposes that learning of sequences relies on memorizing the transitions between adjacent items, while the positional theory suggests that learners encode the items according to their ordinal position in the sequence. Positional learning is assumed to dominate sequential learning. However, human infants exposed to a string of speech sounds can learn transitional (chaining) cues. So far, it is not clear whether birds, an increasingly important model for examining vocal processing, can do this. In this study we use a Go-Nogo design to examine whether zebra finches can use transitional cues to distinguish artificially constructed strings of song elements. Zebra finches were trained with sequences differing in transitional and positional information and next tested with novel strings sharing positional and transitional similarities with the training strings. The results show that they can attend to both transitional and positional cues and that their sequential coding strategies can be biased toward transitional cues depending on the learning context. This article is part of a Special Issue entitled: In Honor of Jerry Hogan.

  18. Budgerigars and zebra finches differ in how they generalize in an artificial grammar learning experiment.

    PubMed

    Spierings, Michelle J; Ten Cate, Carel

    2016-07-01

    The ability to abstract a regularity that underlies strings of sounds is a core mechanism of the language faculty but might not be specific to language learning or even to humans. It is unclear whether and to what extent nonhuman animals possess the ability to abstract regularities defining the relation among arbitrary auditory items in a string and to generalize this abstraction to strings of acoustically novel items. In this study we tested these abilities in a songbird (zebra finch) and a parrot species (budgerigar). Subjects were trained in a go/no-go design to discriminate between two sets of sound strings arranged in an XYX or an XXY structure. After this discrimination was acquired, each subject was tested with test strings that were structurally identical to the training strings but consisted of either new combinations of known elements or of novel elements belonging to other element categories. Both species learned to discriminate between the two stimulus sets. However, their responses to the test strings were strikingly different. Zebra finches categorized test stimuli with previously heard elements by the ordinal position that these elements occupied in the training strings, independent of string structure. In contrast, the budgerigars categorized both novel combinations of familiar elements as well as strings consisting of novel element types by their underlying structure. They thus abstracted the relation among items in the XYX and XXY structures, an ability similar to that shown by human infants and indicating a level of abstraction comparable to analogical reasoning. PMID:27325756

  19. An eye for beauty: lateralized visual stimulation of courtship behavior and mate preferences in male zebra finches, Taeniopygia guttata.

    PubMed

    Templeton, Jennifer J; McCracken, Brianna G; Sher, Melissa; Mountjoy, D James

    2014-02-01

    Research on intersexual selection focuses on traits that have evolved for attracting mates and the consequences of mate choice. However, little is known about the cognitive and neural mechanisms that allow choosers to discriminate among potential mates and express an attraction to specific traits. Preferential use of the right eye during lateral displays in zebra finches, and lateralized expression of intermediate early genes in the left hemisphere during courtship led us to hypothesize that: (1) visual information from each eye differentially mediates courtship responses to potential mates; and (2) the ability to discriminate among mates and prefer certain mates over others is lateralized in the right eye/left hemisphere system of zebra finch brains. First, we exposed male zebra finches to females when using left, right or both eyes. Males courted more when the right eye was available than when only the left eye was used. Secondly, male preference for females - using beak color to indicate female quality - was tested. Right-eyed and binocular males associated with and courted orange-beaked more than gray-beaked females; whereas left-eyed males showed no preference. Lateral displays and eye use in male zebra finches increase their attractiveness and ability to assess female quality, potentially enhancing reproductive success. This article is part of a Special Issue entitled: CO3 2013.

  20. Colour vision and background adaptation in a passerine bird, the zebra finch (Taeniopygia guttata)

    PubMed Central

    2016-01-01

    Today, there is good knowledge of the physiological basis of bird colour vision and how mathematical models can be used to predict visual thresholds. However, we still know only little about how colour vision changes between different viewing conditions. This limits the understanding of how colour signalling is configured in habitats where the light of the illumination and the background may shift dramatically. I examined how colour discrimination in zebra finch (Taeniopygia guttata) is affected by adaptation to different backgrounds. I trained finches in a two-alternative choice task, to choose between red discs displayed on backgrounds with different colours. I found that discrimination thresholds correlate with stimulus contrast to the background. Thresholds are low, and in agreement with model predictions, for a background with a red colour similar to the discs. For the most contrasting green background, thresholds are about five times higher than this. Subsequently, I trained the finches for the detection of single discs on a grey background. Detection thresholds are about 2.5 to 3 times higher than discrimination thresholds. This study demonstrates close similarities in human and bird colour vision, and the quantitative data offer a new possibility to account for shifting viewing conditions in colour vision models. PMID:27703702

  1. Muscle activation patterns and motor anatomy of Anna's hummingbirds Calypte anna and zebra finches Taeniopygia guttata.

    PubMed

    Donovan, Edward R; Keeney, Brooke K; Kung, Eric; Makan, Sirish; Wild, J Martin; Altshuler, Douglas L

    2013-01-01

    Flying animals exhibit profound transformations in anatomy, physiology, and neural architecture. Although much is known about adaptations in the avian skeleton and musculature, less is known about neuroanatomy and motor unit integration for bird flight. Hummingbirds are among the most maneuverable and specialized of vertebrate fliers, and two unusual neuromuscular features have been previously reported: (1) the pectoralis major has a unique distribution pattern of motor end plates (MEPs) compared with all other birds and (2) electromyograms (EMGs) from the hummingbird's pectoral muscles, the pectoralis major and the supracoracoideus, show activation bursts composed of one or a few spikes that appear to have a very consistent pattern. Here, we place these findings in a broader context by comparing the MEPs, EMGs, and organization of the spinal motor neuron pools of flight muscles of Anna's hummingbird Calypte anna, zebra finches Taeniopygia guttata, and, for MEPs, several other species. The previously shown MEP pattern of the hummingbird pectoralis major is not shared with its closest taxonomic relative, the swift, and appears to be unique to hummingbirds. MEP arrangements in previously undocumented wing muscles show patterns that differ somewhat from other avian muscles. In the parallel-fibered strap muscles of the shoulder, MEP patterns appear to relate to muscle length, with the smallest muscles having fibers that span the entire muscle. MEP patterns in pennate distal wing muscles were the same regardless of size, with tightly clustered bands in the middle portion of the muscle, not evenly distributed bands over the muscle's entire length. Muscle activations were examined during slow forward flight in both species, during hovering in hummingbirds, and during slow ascents in zebra finches. The EMG bursts of a wing muscle, the pronator superficialis, were highly variable in peak number, size, and distribution across wingbeats for both species. In the pectoralis

  2. “Bird Song Metronomics”: Isochronous Organization of Zebra Finch Song Rhythm

    PubMed Central

    Norton, Philipp; Scharff, Constance

    2016-01-01

    The human capacity for speech and vocal music depends on vocal imitation. Songbirds, in contrast to non-human primates, share this vocal production learning with humans. The process through which birds and humans learn many of their vocalizations as well as the underlying neural system exhibit a number of striking parallels and have been widely researched. In contrast, rhythm, a key feature of language, and music, has received surprisingly little attention in songbirds. Investigating temporal periodicity in bird song has the potential to inform the relationship between neural mechanisms and behavioral output and can also provide insight into the biology and evolution of musicality. Here we present a method to analyze birdsong for an underlying rhythmic regularity. Using the intervals from one note onset to the next as input, we found for each bird an isochronous sequence of time stamps, a “signal-derived pulse,” or pulseS, of which a subset aligned with all note onsets of the bird's song. Fourier analysis corroborated these results. To determine whether this finding was just a byproduct of the duration of notes and intervals typical for zebra finches but not dependent on the individual duration of elements and the sequence in which they are sung, we compared natural songs to models of artificial songs. Note onsets of natural song deviated from the pulseS significantly less than those of artificial songs with randomized note and gap durations. Thus, male zebra finch song has the regularity required for a listener to extract a perceived pulse (pulseP), as yet untested. Strikingly, in our study, pulsesS that best fit note onsets often also coincided with the transitions between sub-note elements within complex notes, corresponding to neuromuscular gestures. Gesture durations often equaled one or more pulseS periods. This suggests that gesture duration constitutes the basic element of the temporal hierarchy of zebra finch song rhythm, an interesting parallel to the

  3. Personality over ontogeny in zebra finches: long-term repeatable traits but unstable behavioural syndromes.

    PubMed

    Wuerz, Yvonne; Krüger, Oliver

    2015-01-01

    A crucial assumption of animal personality research is that behaviour is consistent over time, showing a high repeatability within individuals. This assumption is often made, sometimes tested using short time intervals between behavioural tests, but rarely thoroughly investigated across long time intervals crossing different stages of ontogeny. We performed such a longitudinal test across three life stages in zebra finches (Taeniopygia guttata), representing about 15-20% of their life span in captivity, and found repeatabilities ranging from 0.03 to 0.67. Fearlessness and exploration were the most repeatable traits both within and across life stages. Activity and aggression were repeatable across, but not or only partly within life stages. Boldness was not repeatable. Furthermore, we found no evidence for a consistent behavioural syndrome structure across ontogeny. Our results indicate that the consistency of behavioural traits and their correlations might be overestimated and suggest that life-long stability of animal personality should not simply be assumed. PMID:26813709

  4. Kinematics of flap-bounding flight in the zebra finch over a wide range of speeds

    PubMed

    Tobalske; Peacock; Dial

    1999-07-01

    It has been proposed elsewhere that flap-bounding, an intermittent flight style consisting of flapping phases interspersed with flexed-wing bounds, should offer no savings in average mechanical power relative to continuous flapping unless a bird flies 1.2 times faster than its maximum range speed (Vmr). Why do some species use intermittent bounds at speeds slower than 1.2Vmr? The 'fixed-gear hypothesis' suggests that flap-bounding is used to vary mean power output in small birds that are otherwise constrained by muscle physiology and wing anatomy to use a fixed muscle shortening velocity and pattern of wing motion at all flight speeds; the 'body-lift hypothesis' suggests that some weight support during bounds could make flap-bounding flight aerodynamically advantageous in comparison with continuous flapping over most forward flight speeds. To test these predictions, we studied high-speed film recordings (300 Hz) of wing and body motion in zebra finches (Taenopygia guttata, mean mass 13.2 g, N=4) taken as the birds flew in a variable-speed wind tunnel (0-14 m s-1). The zebra finches used flap-bounding flight at all speeds, so their flight style was unique compared with that of birds that facultatively shift from continuous flapping or flap-gliding at slow speeds to flap-bounding at fast speeds. There was a significant effect of flight speed on all measured aspects of wing motion except percentage of the wingbeat spent in downstroke. Changes in angular velocity of the wing indicated that contractile velocity in the pectoralis muscle changed with flight speed, which is not consistent with the fixed-gear hypothesis. Although variation in stroke-plane angle relative to the body, pronation angle of the wing and wing span at mid-upstroke showed that the zebra finch changed within-wingbeat geometries according to speed, a vortex-ring gait with a feathered upstroke appeared to be the only gait used during flapping. In contrast, two small species that use continuous flapping

  5. Patterns of call communication between group-housed zebra finches change during the breeding cycle.

    PubMed

    Gill, Lisa F; Goymann, Wolfgang; Ter Maat, Andries; Gahr, Manfred

    2015-10-06

    Vocal signals such as calls play a crucial role for survival and successful reproduction, especially in group-living animals. However, call interactions and call dynamics within groups remain largely unexplored because their relation to relevant contexts or life-history stages could not be studied with individual-level resolution. Using on-bird microphone transmitters, we recorded the vocalisations of individual zebra finches (Taeniopygia guttata) behaving freely in social groups, while females and males previously unknown to each other passed through different stages of the breeding cycle. As birds formed pairs and shifted their reproductive status, their call repertoire composition changed. The recordings revealed that calls occurred non-randomly in fine-tuned vocal interactions and decreased within groups while pair-specific patterns emerged. Call-type combinations of vocal interactions changed within pairs and were associated with successful egg-laying, highlighting a potential fitness relevance of calling dynamics in communication systems.

  6. Diet, maternal condition, and offspring sex ratio in the zebra finch, Poephila guttata

    PubMed Central

    Bradbury, R. B.; Blakey, J. K.

    1998-01-01

    Where maternal condition affects condition and reproductive potential of offspring differentially with respect to sex, mothers in relatively good condition should produce more of the sex whose fitness is more dependent on condition. We experimentally manipulated body-condition in unmated zebra finches by feeding them for three months on high- or low-quality diets. Birds were then allowed to breed, while keeping the same diets. Females on the lower quality diet were in better condition and hatched significantly more males than females. Poorer condition females hatched an equal sex ratio. Chicks fed on the low-quality diet, but not on the high-quality diet, showed female-biased mortality. These results show that facultative sex ratio manipulation and sex-biased mortality can act together to produce extreme sex ratios in this vertebrate.

  7. Personality over ontogeny in zebra finches: long-term repeatable traits but unstable behavioural syndromes

    PubMed Central

    2015-01-01

    A crucial assumption of animal personality research is that behaviour is consistent over time, showing a high repeatability within individuals. This assumption is often made, sometimes tested using short time intervals between behavioural tests, but rarely thoroughly investigated across long time intervals crossing different stages of ontogeny. We performed such a longitudinal test across three life stages in zebra finches (Taeniopygia guttata), representing about 15-20% of their life span in captivity, and found repeatabilities ranging from 0.03 to 0.67. Fearlessness and exploration were the most repeatable traits both within and across life stages. Activity and aggression were repeatable across, but not or only partly within life stages. Boldness was not repeatable. Furthermore, we found no evidence for a consistent behavioural syndrome structure across ontogeny. Our results indicate that the consistency of behavioural traits and their correlations might be overestimated and suggest that life-long stability of animal personality should not simply be assumed. PMID:26813709

  8. Inhibition protects acquired song segments during vocal learning in zebra finches

    PubMed Central

    Vallentin, Daniela; Kosche, Georg; Lipkind, Dina; Long, Michael A.

    2016-01-01

    Vocal imitation involves incorporating instructive auditory information into relevant motor circuits through processes that are poorly understood. In zebra finches, we find that exposure to a tutor’s song drives spiking activity within premotor neurons in the juvenile but that inhibition suppresses such responses upon learning in adulthood. We measure inhibitory currents evoked by the tutor song throughout development while simultaneously quantifying each bird’s learning trajectory. Surprisingly, we find that the maturation of synaptic inhibition onto premotor neurons is correlated with learning but not age. We used synthetic tutoring to demonstrate that inhibition is selective for specific song elements that have already been learned and not those still in refinement. Our results suggest that structured inhibition is playing a crucial role during song acquisition, enabling a piece-by-piece mastery of complex tasks. PMID:26816377

  9. A neural circuit mechanism for regulating vocal variability during song learning in zebra finches.

    PubMed

    Garst-Orozco, Jonathan; Babadi, Baktash; Ölveczky, Bence P

    2014-01-01

    Motor skill learning is characterized by improved performance and reduced motor variability. The neural mechanisms that couple skill level and variability, however, are not known. The zebra finch, a songbird, presents a unique opportunity to address this question because production of learned song and induction of vocal variability are instantiated in distinct circuits that converge on a motor cortex analogue controlling vocal output. To probe the interplay between learning and variability, we made intracellular recordings from neurons in this area, characterizing how their inputs from the functionally distinct pathways change throughout song development. We found that inputs that drive stereotyped song-patterns are strengthened and pruned, while inputs that induce variability remain unchanged. A simple network model showed that strengthening and pruning of action-specific connections reduces the sensitivity of motor control circuits to variable input and neural 'noise'. This identifies a simple and general mechanism for learning-related regulation of motor variability.

  10. Neural circuits. Inhibition protects acquired song segments during vocal learning in zebra finches.

    PubMed

    Vallentin, Daniela; Kosche, Georg; Lipkind, Dina; Long, Michael A

    2016-01-15

    Vocal imitation involves incorporating instructive auditory information into relevant motor circuits through processes that are poorly understood. In zebra finches, we found that exposure to a tutor's song drives spiking activity within premotor neurons in the juvenile, whereas inhibition suppresses such responses upon learning in adulthood. We measured inhibitory currents evoked by the tutor song throughout development while simultaneously quantifying each bird's learning trajectory. Surprisingly, we found that the maturation of synaptic inhibition onto premotor neurons is correlated with learning but not age. We used synthetic tutoring to demonstrate that inhibition is selective for specific song elements that have already been learned and not those still in refinement. Our results suggest that structured inhibition plays a crucial role during song acquisition, enabling a piece-by-piece mastery of complex tasks. PMID:26816377

  11. Sex-Specific Audience Effect in the Context of Mate Choice in Zebra Finches.

    PubMed

    Kniel, Nina; Bender, Stefanie; Witte, Klaudia

    2016-01-01

    Animals observing conspecifics during mate choice can gain additional information about potential mates. However, the presence of an observer, if detected by the observed individuals, can influence the nature of the behavior of the observed individuals, called audience effect. In zebra finches (Taeniopygia guttata castanotis), domesticated males show an audience effect during mate choice. However, whether male and female descendants of the wild form show an audience effect during mate choice is unknown. Therefore, we conducted an experiment where male and female focal birds could choose between two distinctive phenotypes of the opposite sex, an artificially adorned stimulus bird with a red feather on the forehead and an unadorned stimulus bird, two times consecutively, once without an audience and once with an audience bird (same sex as test bird). Males showed an audience effect when an audience male was present and spent more time with adorned and less time with unadorned females compared to when there was no audience present. The change in time spent with the respective stimulus females was positively correlated with the time that the audience male spent in front of its cage close to the focal male. Females showed no change in mate choice when an audience female was present, but their motivation to associate with both stimulus males decreased. In a control for mate-choice consistency there was no audience in either test. Here, both focal females and focal males chose consistently without a change in choosing motivation. Our results showed that there is an audience effect on mate choice in zebra finches and that the response to a same-sex audience was sex-specific.

  12. Sex-Specific Audience Effect in the Context of Mate Choice in Zebra Finches

    PubMed Central

    Kniel, Nina; Bender, Stefanie; Witte, Klaudia

    2016-01-01

    Animals observing conspecifics during mate choice can gain additional information about potential mates. However, the presence of an observer, if detected by the observed individuals, can influence the nature of the behavior of the observed individuals, called audience effect. In zebra finches (Taeniopygia guttata castanotis), domesticated males show an audience effect during mate choice. However, whether male and female descendants of the wild form show an audience effect during mate choice is unknown. Therefore, we conducted an experiment where male and female focal birds could choose between two distinctive phenotypes of the opposite sex, an artificially adorned stimulus bird with a red feather on the forehead and an unadorned stimulus bird, two times consecutively, once without an audience and once with an audience bird (same sex as test bird). Males showed an audience effect when an audience male was present and spent more time with adorned and less time with unadorned females compared to when there was no audience present. The change in time spent with the respective stimulus females was positively correlated with the time that the audience male spent in front of its cage close to the focal male. Females showed no change in mate choice when an audience female was present, but their motivation to associate with both stimulus males decreased. In a control for mate-choice consistency there was no audience in either test. Here, both focal females and focal males chose consistently without a change in choosing motivation. Our results showed that there is an audience effect on mate choice in zebra finches and that the response to a same-sex audience was sex-specific. PMID:26839957

  13. Anatomically Discrete Sex Differences in Neuroplasticity in Zebra Finches as Reflected by Perineuronal Nets

    PubMed Central

    Cornez, Gilles; ter Haar, Sita M.; Cornil, Charlotte A.; Balthazart, Jacques

    2015-01-01

    Large morphological sex differences in the vertebrate brain were initially identified in song control nuclei of oscines. Besides gross differences between volumes of nuclei in males and females, sex differences also concern the size and dendritic arborization of neurons and various neurochemical markers, such as the calcium-binding protein parvalbumin (PV). Perineuronal nets (PNN) of the extracellular matrix are aggregates of different compounds, mainly chondroitin sulfate proteoglycans, that surround subsets of neurons, often expressing PV. PNN develop in zebra finches song control nuclei around the end of the sensitive period for song learning and tutor deprivation, known to delay the end of the song learning sensitive period, decreases the numbers of PNN in HVC. We demonstrate here the existence in zebra finches of a major sex difference (males > females) affecting the number of PNN (especially those surrounding PV-positive cells) in HVC and to a smaller extent the robust nucleus of the arcopallium, RA, the two main nuclei controlling song production. These differences were not present in Area X and LMAN, the lateral magnocellular nucleus of the anterior nidopallium. A dense expression of material immunoreactive for chondroitin sulfate was also detected in several nuclei of the auditory and visual pathways. This material was often organized in perineuronal rings but quantification of these PNN did not reveal any sex difference with the exception that the percentage of PNN surrounding PV-ir cells in the dorsal lateral mesencephalic nucleus, MLd, was larger in females than in males, a sex difference in the opposite direction compared to what is seen in HVC and RA. These data confirm and extend previous studies demonstrating the sex difference affecting PNN in HVC-RA by showing that this sex difference is anatomically specific and does not concern visual or auditory pathways. PMID:25848776

  14. Zebra finch males compensate in plumage ornaments at sexual maturation for a bad start in life

    PubMed Central

    2015-01-01

    Background An individual's fitness in part depends on the characteristics of the mate so that sexually attractive ornaments, as signals of quality, are used in mate choice. Often such ornaments develop already early in life and thus are affected by nutritional conditions experienced then. Individuals thus should benefit by compensating as soon as possible for poor initial development of ornaments, to be attractive already at sexual maturity. Here, we tested whether early nutritional stress affects the cheek patch size of male Zebra finches (Taeniopygia guttata), which are important in mate choice, and whether a small cheek patch size early on is compensated at sexual maturation. Furthermore we tested whether exploration behaviour is affected by such a compensation, as shown for other compensatory growth trajectories. Results Zebra finch males which were raised under poorer nutritional conditions initially expressed smaller cheek patches at day 50 post-hatching but then compensated in cheek patch size already at 65 days, i.e. when becoming sexually mature. Furthermore, compensatory growth in cheek patch during adolescence was negatively correlated with activity and exploration behaviour, measured in a novel environment. Conclusion This compensation in cheek patch size benefits male attractiveness but also was related to less exploration behaviour, an established proxy for avian personality traits. We discuss the possibility that compensatory priorities exist so that not all deficits from a bad start are caught-up at the same time. Resource allocation to compensate for poorly expressed traits is likely to have evolved to optimise traits by the time they are most beneficial. PMID:26816511

  15. Natural melatonin fluctuation and its minimally invasive simulation in the zebra finch

    PubMed Central

    Trost, Lisa; Ter Maat, Andries; Gahr, Manfred

    2016-01-01

    Melatonin is a key hormone in the regulation of circadian rhythms of vertebrates, including songbirds. Understanding diurnal melatonin fluctuations and being able to reverse or simulate natural melatonin levels are critical to investigating the influence of melatonin on various behaviors such as singing in birds. Here we give a detailed overview of natural fluctuations in plasma melatonin concentration throughout the night in the zebra finch. As shown in previous studies, we confirm that “lights off” initiates melatonin production at night in a natural situation. Notably, we find that melatonin levels return to daytime levels as early as two hours prior to the end of the dark-phase in some individuals and 30 min before “lights on” in all animals, suggesting that the presence of light in the morning is not essential for cessation of melatonin production in zebra finches. Thus, the duration of melatonin production seems not to be specified by the length of night and might therefore be less likely to directly couple circadian and annual rhythms. Additionally, we show that natural melatonin levels can be successfully simulated through a combination of light-treatment (daytime levels during subjective night) and the application of melatonin containing skin-cream (nighttime levels during subjective day). Moreover, natural levels and their fluctuation in the transition from day to night can be imitated, enabling the decoupling of the effects of melatonin, for example on neuronal activity, from sleep and circadian rhythmicity. Taken together, our high-resolution profile of natural melatonin levels and manipulation techniques open up new possibilities to answer various melatonin related questions in songbirds. PMID:27123378

  16. Sex-Specific Audience Effect in the Context of Mate Choice in Zebra Finches.

    PubMed

    Kniel, Nina; Bender, Stefanie; Witte, Klaudia

    2016-01-01

    Animals observing conspecifics during mate choice can gain additional information about potential mates. However, the presence of an observer, if detected by the observed individuals, can influence the nature of the behavior of the observed individuals, called audience effect. In zebra finches (Taeniopygia guttata castanotis), domesticated males show an audience effect during mate choice. However, whether male and female descendants of the wild form show an audience effect during mate choice is unknown. Therefore, we conducted an experiment where male and female focal birds could choose between two distinctive phenotypes of the opposite sex, an artificially adorned stimulus bird with a red feather on the forehead and an unadorned stimulus bird, two times consecutively, once without an audience and once with an audience bird (same sex as test bird). Males showed an audience effect when an audience male was present and spent more time with adorned and less time with unadorned females compared to when there was no audience present. The change in time spent with the respective stimulus females was positively correlated with the time that the audience male spent in front of its cage close to the focal male. Females showed no change in mate choice when an audience female was present, but their motivation to associate with both stimulus males decreased. In a control for mate-choice consistency there was no audience in either test. Here, both focal females and focal males chose consistently without a change in choosing motivation. Our results showed that there is an audience effect on mate choice in zebra finches and that the response to a same-sex audience was sex-specific. PMID:26839957

  17. An experimental test of condition-dependent male and female mate choice in zebra finches.

    PubMed

    Holveck, Marie-Jeanne; Geberzahn, Nicole; Riebel, Katharina

    2011-01-01

    In mating systems with social monogamy and obligatory bi-parental care, such as found in many songbird species, male and female fitness depends on the combined parental investment. Hence, both sexes should gain from choosing mates in high rather than low condition. However, theory also predicts that an individual's phenotypic quality can constrain choice, if low condition individuals cannot afford prolonged search efforts and/or face higher risk of rejection. In systems with mutual mate choice, the interaction between male and female condition should thus be a better predictor of choice than either factor in isolation. To address this prediction experimentally, we manipulated male and female condition and subsequently tested male and female mating preferences in zebra finches Taeniopygia guttata, a songbird species with mutual mate choice and obligatory bi-parental care. We experimentally altered phenotypic quality by manipulating the brood size in which the birds were reared. Patterns of association for high- or low-condition individuals of the opposite sex differed for male and female focal birds when tested in an 8-way choice arena. Females showed repeatable condition-assortative preferences for males matching their own rearing background. Male preferences were also repeatable, but not predicted by their own or females' rearing background. In combination with a brief review of the literature on condition-dependent mate choice in the zebra finch we discuss whether the observed sex differences and between-studies differences arise because males and females differ in context sensitivity (e.g. male-male competition suppressing male mating preferences), sampling strategies or susceptibility to rearing conditions (e.g. sex-specific effect on physiology). While a picture emerges that juvenile and current state indeed affect preferences, the development and context-dependency of mutual state-dependent mate choice warrants further study. PMID:21901147

  18. An Experimental Test of Condition-Dependent Male and Female Mate Choice in Zebra Finches

    PubMed Central

    Holveck, Marie-Jeanne; Geberzahn, Nicole; Riebel, Katharina

    2011-01-01

    In mating systems with social monogamy and obligatory bi-parental care, such as found in many songbird species, male and female fitness depends on the combined parental investment. Hence, both sexes should gain from choosing mates in high rather than low condition. However, theory also predicts that an individual's phenotypic quality can constrain choice, if low condition individuals cannot afford prolonged search efforts and/or face higher risk of rejection. In systems with mutual mate choice, the interaction between male and female condition should thus be a better predictor of choice than either factor in isolation. To address this prediction experimentally, we manipulated male and female condition and subsequently tested male and female mating preferences in zebra finches Taeniopygia guttata, a songbird species with mutual mate choice and obligatory bi-parental care. We experimentally altered phenotypic quality by manipulating the brood size in which the birds were reared. Patterns of association for high- or low-condition individuals of the opposite sex differed for male and female focal birds when tested in an 8-way choice arena. Females showed repeatable condition-assortative preferences for males matching their own rearing background. Male preferences were also repeatable, but not predicted by their own or females' rearing background. In combination with a brief review of the literature on condition-dependent mate choice in the zebra finch we discuss whether the observed sex differences and between-studies differences arise because males and females differ in context sensitivity (e.g. male-male competition suppressing male mating preferences), sampling strategies or susceptibility to rearing conditions (e.g. sex-specific effect on physiology). While a picture emerges that juvenile and current state indeed affect preferences, the development and context-dependency of mutual state-dependent mate choice warrants further study. PMID:21901147

  19. Natural melatonin fluctuation and its minimally invasive simulation in the zebra finch.

    PubMed

    Seltmann, Susanne; Trost, Lisa; Ter Maat, Andries; Gahr, Manfred

    2016-01-01

    Melatonin is a key hormone in the regulation of circadian rhythms of vertebrates, including songbirds. Understanding diurnal melatonin fluctuations and being able to reverse or simulate natural melatonin levels are critical to investigating the influence of melatonin on various behaviors such as singing in birds. Here we give a detailed overview of natural fluctuations in plasma melatonin concentration throughout the night in the zebra finch. As shown in previous studies, we confirm that "lights off" initiates melatonin production at night in a natural situation. Notably, we find that melatonin levels return to daytime levels as early as two hours prior to the end of the dark-phase in some individuals and 30 min before "lights on" in all animals, suggesting that the presence of light in the morning is not essential for cessation of melatonin production in zebra finches. Thus, the duration of melatonin production seems not to be specified by the length of night and might therefore be less likely to directly couple circadian and annual rhythms. Additionally, we show that natural melatonin levels can be successfully simulated through a combination of light-treatment (daytime levels during subjective night) and the application of melatonin containing skin-cream (nighttime levels during subjective day). Moreover, natural levels and their fluctuation in the transition from day to night can be imitated, enabling the decoupling of the effects of melatonin, for example on neuronal activity, from sleep and circadian rhythmicity. Taken together, our high-resolution profile of natural melatonin levels and manipulation techniques open up new possibilities to answer various melatonin related questions in songbirds. PMID:27123378

  20. Brain pathways for learned and unlearned vocalizations differ in zebra finches.

    PubMed

    Simpson, H B; Vicario, D S

    1990-05-01

    Male zebra finches sing, females do not. However, both sexes produce the "long call" when placed in visual isolation. This call is sexually dimorphic; it includes learned components in males but not in females. The 3 learned features of the male long call are a high fundamental frequency, a fast frequency modulation, and a short, stable duration. These features are learned by the male during development, as is song. Since similar features are also found in song syllables, we wanted to know whether long-call production depends on the same CNS pathway that controls song production. Three critical components of the song pathway are telencephalic nuclei HVC, RA, and the tracheosyringeal (ts) nerves innervating the syrinx. In male zebra finches, bilateral section of the ts nerves affected the fundamental frequency and fast frequency modulations of both the long call and song but left the temporal features intact. Ts nerve section had no effect on the female long call. Bilateral lesions of either HVC or RA in males affected the fundamental frequency, fast frequency modulations, and temporal structure of both the long call and song. Similar lesions had no effect on the female long call. These results demonstrate that HVC, RA, and the ts nerves make critical contributions to the acoustic features of the male long call and song, while the temporal pattern depends on HVC and RA but not the ts nerves. HVC and RA lesions remove all the learned features that distinguish the male call and reveal a simple unlearned vocalization shared by both sexes. We suggest that the learned features of oscine songbird vocalizations are controlled by a telencephalic pathway that acts in concert with other pathways responsible for simpler, unlearned vocalizations.

  1. Pair Bond Formation is Impaired by VPAC Receptor Antagonism in the Socially Monogamous Zebra Finch

    PubMed Central

    Kingsbury, Marcy A.; Goodson, James L.

    2014-01-01

    A variety of recent data demonstrate that vasoactive intestinal polypeptide (VIP) and VPAC receptors (which bind VIP, and to a lesser extent, pituitary adenylatecyclase activating peptide) are important for numerous social behaviors in songbirds, including grouping and aggression, although VIP relates to these behaviors in a site-specific manner. In order to determine the global effects of central VPAC receptor activation on social behavior, we here infused a VPAC receptor antagonist or vehicle twice daily into the lateral ventricle of colony-housed male and female zebra finches and quantified a wide range of behaviors. Aggressive behaviors were not altered by ventricular infusions, consistent with known opposing, site-specific relationships of VIP innervation to aggression. Courtship and self-maintenance behaviors were likewise not altered. However, VPAC antagonism produced significant deficits in pair bonding. Antagonist subjects took longer to form a pair bond and were paired for significantly fewer observation sessions relative to control subjects (median 1.5 of 6 observation sessions for antagonist subjects versus 4 for control subjects). Antagonist subjects were also significantly less likely to be paired in the final observation session. Based on the known distribution of VPAC receptors in finches and other vertebrates, we propose that VPAC receptors may mediate pair bonding via a variety of brain areas that are known to be important for the establishment of partner preferences in voles, including the lateral septum, ventral tegmental area, nucleus accumbens and ventral pallidum. PMID:25014003

  2. Frequency-range discriminations: special and general abilities in zebra finches (Taeniopygia guttata) and humans (Homo sapiens).

    PubMed

    Weisman, R; Njegovan, M; Sturdy, C; Phillmore, L; Coyle, J; Mewhort, D

    1998-09-01

    The acoustic frequency ranges in birdsongs and human speech can provide important pitch cues for recognition. Zebra finches and humans were trained to sort contiguous frequencies into 3 or 8 ranges, based on associations between the ranges and reward. The 3-range task was conducted separately in 3 spectral regions. Zebra finches discriminated 3 ranges in the medium and high spectral regions faster than in the low region and discriminated 8 ranges with precision. Humans discriminated 3 ranges in all 3 spectral regions to the same modest standard and acquired only a crude discrimination of the lowest and highest of 8 ranges. The results indicate that songbirds have a special sensitivity to the pitches in conspecific songs and, relative to humans, have a remarkable general ability to sort pitches into ranges.

  3. Frequency-range discriminations: special and general abilities in zebra finches (Taeniopygia guttata) and humans (Homo sapiens).

    PubMed

    Weisman, R; Njegovan, M; Sturdy, C; Phillmore, L; Coyle, J; Mewhort, D

    1998-09-01

    The acoustic frequency ranges in birdsongs and human speech can provide important pitch cues for recognition. Zebra finches and humans were trained to sort contiguous frequencies into 3 or 8 ranges, based on associations between the ranges and reward. The 3-range task was conducted separately in 3 spectral regions. Zebra finches discriminated 3 ranges in the medium and high spectral regions faster than in the low region and discriminated 8 ranges with precision. Humans discriminated 3 ranges in all 3 spectral regions to the same modest standard and acquired only a crude discrimination of the lowest and highest of 8 ranges. The results indicate that songbirds have a special sensitivity to the pitches in conspecific songs and, relative to humans, have a remarkable general ability to sort pitches into ranges. PMID:9770314

  4. Housing conditions and sacrifice protocol affect neural activity and vocal behavior in a songbird species, the zebra finch (Taeniopygia guttata).

    PubMed

    Elie, Julie Estelle; Soula, Hédi Antoine; Trouvé, Colette; Mathevon, Nicolas; Vignal, Clémentine

    2015-12-01

    Individual cages represent a widely used housing condition in laboratories. This isolation represents an impoverished physical and social environment in gregarious animals. It prevents animals from socializing, even when auditory and visual contact is maintained. Zebra finches are colonial songbirds that are widely used as laboratory animals for the study of vocal communication from brain to behavior. In this study, we investigated the effect of single housing on the vocal behavior and the brain activity of male zebra finches (Taeniopygia guttata): male birds housed in individual cages were compared to freely interacting male birds housed as a social group in a communal cage. We focused on the activity of septo-hypothalamic regions of the "social behavior network" (SBN), a set of limbic regions involved in several social behaviors in vertebrates. The activity of four structures of the SBN (BSTm, medial bed nucleus of the stria terminalis; POM, medial preoptic area; lateral septum; ventromedial hypothalamus) and one associated region (paraventricular nucleus of the hypothalamus) was assessed using immunoreactive nuclei density of the immediate early gene Zenk (egr-1). We further assessed the identity of active cell populations by labeling vasotocin (VT). Brain activity was related to behavioral activities of birds like physical and vocal interactions. We showed that individual housing modifies vocal exchanges between birds compared to communal housing. This is of particular importance in the zebra finch, a model species for the study of vocal communication. In addition, a protocol that daily removes one or two birds from the group affects differently male zebra finches depending of their housing conditions: while communally-housed males changed their vocal output, brains of individually housed males show increased Zenk labeling in non-VT cells of the BSTm and enhanced correlation of Zenk-revealed activity between the studied structures. These results show that

  5. Within-year differences in reproductive investment in laboratory zebra finches ( Taeniopygia guttata), an opportunistically breeding bird

    NASA Astrophysics Data System (ADS)

    Williamson, Kathryn; Gilbert, Lucy; Rutstein, Alison N.; Pariser, Emma C.; Graves, Jeff A.

    2008-12-01

    Reproduction in opportunistically breeding bird species has traditionally been considered non-seasonal with individuals taking advantage of favourable environmental conditions as they arise. However, some studies imply that this opportunistic breeding may be superimposed on an underlying seasonality, which has effects on the readiness to breed when conditions are favourable. The zebra finch ( Taeniopygia guttata) is the classic opportunistic breeder and widely used as such in studies. In a series of laboratory-based breeding experiments, we found evidence to suggest that there are seasonal differences in maternal reproductive investment in the zebra finch even when photoperiod, temperature, relative humidity and diet were held constant. Females showed highly significant seasonal differences in clutch size and egg mass with laying order. Clutch size showed a spring/summer peak typical of multi-brooded species in the wild. There was also a significant increase in egg mass with laying order in all seasons except winter. This variation in breeding parameters with season may allow females to adjust investment depending on the potential fitness returns from a given reproductive attempt. These findings also raise a warning about interpreting results of multiple zebra finch breeding experiments that have been carried out in different seasons.

  6. Physiological and behavioral responses to an acute-phase response in zebra finches: immediate and short-term effects.

    PubMed

    Sköld-Chiriac, Sandra; Nord, Andreas; Nilsson, Jan-Åke; Hasselquist, Dennis

    2014-01-01

    Activation of the immune system to clear pathogens and mitigate infection is a costly process that might incur fitness costs. When vertebrates are exposed to pathogens, their first line of defense is the acute-phase response (APR), which consists of a suite of physiological and behavioral changes. The dynamics of the APR are relatively well investigated in mammals and domesticated birds but still rather unexplored in passerine birds. In this study, we injected male zebra finches (Taeniopygia guttata) with a bacterial endotoxin (lipopolysaccharide [LPS]) to assess the potential physiological, immunological, and behavioral responses during the time course of an APR and also to record any potential short-term effects by measuring the birds during the days after the expected APR. We found that LPS-injected zebra finches decreased activity and gained less body mass during the APR, compared to control individuals. In addition, LPS-injected birds increased their production of LPS-reactive antibodies and reduced their metabolic rate during the days after the expected APR. Our results show that zebra finches demonstrate sickness behaviors during an APR but also that physiological effects persist after the expected time course of an APR. These delayed effects might be either a natural part of the progression of an APR, which is probably true for the antibody response, or a short-term carryover effect, which is probably true for the metabolic response.

  7. Is the rate of metabolic ageing and survival determined by Basal metabolic rate in the zebra finch?

    PubMed

    Rønning, Bernt; Moe, Børge; Berntsen, Henrik H; Noreen, Elin; Bech, Claus

    2014-01-01

    The relationship between energy metabolism and ageing is of great interest because aerobic metabolism is the primary source of reactive oxygen species which is believed to be of major importance in the ageing process. We conducted a longitudinal study on captive zebra finches where we tested the effect of age on basal metabolic rate (BMR), as well as the effect of BMR on the rate of metabolic ageing (decline in BMR with age) and survival. Basal metabolic rate declined with age in both sexes after controlling for the effect of body mass, indicating a loss of functionality with age. This loss of functionality could be due to accumulated oxidative damage, believed to increase with increasing metabolic rate, c.f. the free radical theory of ageing. If so, we would expect the rate of metabolic ageing to increase and survival to decrease with increasing BMR. However, we found no effect of BMR on the rate of metabolic ageing. Furthermore, survival was not affected by BMR in the males. In female zebra finches there was a tendency for survival to decrease with increasing BMR, but the effect did not reach significance (P<0.1). Thus, the effect of BMR on the rate of functional deterioration with age, if any, was not strong enough to influence neither the rate of metabolic ageing nor survival in the zebra finches.

  8. Calbindin-D28K expression increases in the dorsolateral hippocampus following corticosterone treatment in female zebra finches (Taeniopygia guttata).

    PubMed

    Ash, Ashley L; Saldanha, Colin J; Bailey, David J

    2012-03-01

    The hippocampus (HP) in zebra finches (Taeniopygia guttata) is important in the consolidation of spatial memories. Chronic, elevated levels of steroid hormones, like the glucocorticoids, can decrease this type of memory function in birds and mammals; neuronal atrophy, loss, and a decrease in synaptic contacts in the mammalian HP are observed as the underlying cause. Calbindin-D28k is constitutively expressed in cells of the nervous system but increases in concentration following a neurotoxic insult, protecting neurons against apoptotic cell death. We hypothesized that treatment of female zebra finches with a glucocorticoid (corticosterone) would increase calbindin expression in the HP and the caudomedial nidopallium (NCM), a region important for perceptual (song) memories, relative to "blank" controls. Additionally, because the HP in zebra finches appears similar to that in mammals, based on a variety of structural and functional factors, and as particular regions of the HP in mammals are more vulnerable to glucocorticoid-induced damage, we also hypothesized that expression of calbindin would vary among the HP subdivisions. Overall levels of calbindin were higher in the HP of corticosterone-treated birds, due almost entirely to elevated calbindin expression in the dorsolateral subdivision of the HP only. In contrast, the dorsomedial HP, ventral HP, and NCM appear less affected by glucocorticoid exposure. These results suggest a role for glucocorticoids in the modulation of HP- but not NCM-dependent memories as well as a further functional differentiation among the HP subdivisions.

  9. Organization and development of zebra finch HVC and paraHVC based on expression of zRalDH, an enzyme associated with retinoic acid production

    PubMed Central

    Olson, Christopher R.; Rodrigues, Paulo Vianney; Jeong, Jin Kwon; Prahl, Daniel J.; Mello, Claudio V.

    2010-01-01

    The zRalDH gene encodes an aldehyde dehydrogenase associated with the conversion of retinaldehyde (the main vitamin A metabolite) into retinoic acid and its expression is highly enriched in the song control system of adult zebra finches (T. gutatta). Within song control nucleus HVC, zRalDH is specifically expressed in the neurons that project to area X of the striatum. It is also expressed in paraHVC, commonly considered a medial extension of HVC that is closely associated with auditory areas in the caudomedial telencephalon. Here we used in situ hybridization to generate a detailed analysis of HVC and paraHVC based on expression of zRalDH for adult zebra finches of both sexes and for males during the song learning period. We demonstrate that the distribution of zRalDH-positive cells can be used for accurate assessments of HVC and paraHVC in adult and juvenile males. We describe marked developmental changes in the numbers of zRalDH-expressing cells in HVC and paraHVC, reaching a peak at day 50 post-hatch, an effect potentially due to dynamic changes in the population of X-projecting cells in HVC. We also show that zRalDH-expressing cells in adult females, although much less numerous than in males, have a surprisingly broad distribution along the medial-to-lateral extent of HVC but are lacking where paraHVC is found in adult males. Our study thus contributes to our understanding of the nuclear organization of the song system and the dynamics of its developmental changes during the song learning period. PMID:21120932

  10. miR-9 and miR-140-5p target FoxP2 and are regulated as a function of the social context of singing behavior in zebra finches.

    PubMed

    Shi, Zhimin; Luo, Guanzheng; Fu, Lijuan; Fang, Zhide; Wang, XiuJie; Li, XiaoChing

    2013-10-16

    Mutations in the FOXP2 gene cause speech and language impairments, accompanied by structural and functional abnormalities in brain regions underlying speech-related sensory-motor processing, including the striatum and cerebellum. The sequence and expression patterns of FOXP2 are highly conserved among higher vertebrates. In the zebra finch brain, FoxP2 is expressed in Area X, a striatal nucleus required for vocal learning, and reduced FoxP2 expression impairs dendritic development and vocal learning. The FoxP2 gene encodes a transcription factor that controls the expression of many downstream genes. However, how FOXP2 gene expression is regulated is not clearly understood. miRNAs regulate gene expression post-transcriptionally by targeting the 3'-untranslated regions (UTRs) of mRNAs, leading to translational suppression or mRNA degradation. In this study, we identified miR-9 and miR-140-5p as potential regulators of the FoxP2 gene. We show that both miR-9 and miR-140-5p target specific sequences in the FoxP2 3'-UTR and downregulate FoxP2 protein and mRNA expression in vitro. We also show that the expression of miR-9 and miR-140-5p in Area X of the zebra finch brain is regulated during song development in juvenile zebra finches. We further show that in adult zebra finches the expression of miR-9 and miR-140-5p in Area X is regulated as a function of the social context of song behavior in males singing undirected songs. Our findings reveal a post-transcriptional mechanism that regulates FoxP2 expression and suggest that social vocal behavior can influence the basal ganglia circuit controlling vocal learning via a miRNA-FoxP2 gene regulatory network.

  11. Patterns of call communication between group-housed zebra finches change during the breeding cycle

    PubMed Central

    Gill, Lisa F; Goymann, Wolfgang; Ter Maat, Andries; Gahr, Manfred

    2015-01-01

    Vocal signals such as calls play a crucial role for survival and successful reproduction, especially in group-living animals. However, call interactions and call dynamics within groups remain largely unexplored because their relation to relevant contexts or life-history stages could not be studied with individual-level resolution. Using on-bird microphone transmitters, we recorded the vocalisations of individual zebra finches (Taeniopygia guttata) behaving freely in social groups, while females and males previously unknown to each other passed through different stages of the breeding cycle. As birds formed pairs and shifted their reproductive status, their call repertoire composition changed. The recordings revealed that calls occurred non-randomly in fine-tuned vocal interactions and decreased within groups while pair-specific patterns emerged. Call-type combinations of vocal interactions changed within pairs and were associated with successful egg-laying, highlighting a potential fitness relevance of calling dynamics in communication systems. DOI: http://dx.doi.org/10.7554/eLife.07770.001 PMID:26441403

  12. Timing of Ossification in Duck, Quail, and Zebra Finch: Intraspecific Variation, Heterochronies, and Life History Evolution

    PubMed Central

    Mitgutsch, Christian; Wimmer, Corinne; Sánchez-Villagra, Marcelo R.; Hahnloser, Richard; Schneider, Richard A.

    2011-01-01

    Skeletogenic heterochronies have gained much attention in comparative developmental biology. The temporal appearance of mineralized individual bones in a species – the species ossification sequence – is an excellent marker in this kind of study. Several publications describe interspecific variation, but only very few detail intraspecific variation. In this study, we describe and analyze the temporal order of ossification of skeletal elements in the zebra finch, Taeniopygia guttata, the Japanese quail, Coturnix coturnix japonica, and the White Pekin duck, a domestic race of the mallard Anas platyrhynchos, and explore patterns of intraspecific variation in these events. The overall sequences were found to be conserved. In the duck, variability is present in the relative timing of ossification in the occipital, the basisphenoid and the otic regions of the skull and the phalanges in the postcranium. This variation appears generally in close temporal proximity. Comparison with previously published data shows differences in ossification sequence in the skull, the feet, and the pelvis in the duck, and especially the pelvis in the quail. This clearly documents variability among different breeds. PMID:21728797

  13. Song discrimination learning in zebra finches induces highly divergent responses to novel songs.

    PubMed

    Verzijden, Machteld N; Etman, Eric; van Heijningen, Caroline; van der Linden, Marianne; ten Cate, Carel

    2007-01-22

    Perceptual biases can shape the evolution of signal form. Understanding the origin and direction of such biases is therefore crucial for understanding signal evolution. Many animals learn about species-specific signals. Discrimination learning using simple stimuli varying in one dimension (e.g. amplitude, wavelength) can result in perceptual biases with preferences for specific novel stimuli, depending on the stimulus dimensions. We examine how this translates to discrimination learning involving complex communication signals; birdsongs. Zebra finches (Taeniopygia guttata) were trained to discriminate between two artificial songs, using a Go/No-Go procedure. The training songs in experiment 1 differed in the number of repeats of a particular element. The songs in experiment 2 differed in the position of an odd element in a series of repeated elements. We examined generalization patterns by presenting novel songs with more or fewer repeated elements (experiment 1), or with the odd element earlier or later in the repeated element sequence (experiment 2). Control birds were trained with only one song. The generalization curves obtained from (i) control birds, (ii) experimental birds in experiment 1, and (iii) experimental birds in experiment 2 showed large and systematic differences from each other. Birds in experiment 1, but not 2, responded more strongly to specific novel songs than to training songs, showing 'peak shift'. The outcome indicates that learning about communication signals may give rise to perceptual biases that may drive signal evolution.

  14. A neural circuit mechanism for regulating vocal variability during song learning in zebra finches

    PubMed Central

    Garst-Orozco, Jonathan; Babadi, Baktash; Ölveczky, Bence P

    2014-01-01

    Motor skill learning is characterized by improved performance and reduced motor variability. The neural mechanisms that couple skill level and variability, however, are not known. The zebra finch, a songbird, presents a unique opportunity to address this question because production of learned song and induction of vocal variability are instantiated in distinct circuits that converge on a motor cortex analogue controlling vocal output. To probe the interplay between learning and variability, we made intracellular recordings from neurons in this area, characterizing how their inputs from the functionally distinct pathways change throughout song development. We found that inputs that drive stereotyped song-patterns are strengthened and pruned, while inputs that induce variability remain unchanged. A simple network model showed that strengthening and pruning of action-specific connections reduces the sensitivity of motor control circuits to variable input and neural ‘noise’. This identifies a simple and general mechanism for learning-related regulation of motor variability. DOI: http://dx.doi.org/10.7554/eLife.03697.001 PMID:25497835

  15. Behavior-linked FoxP2 regulation enables zebra finch vocal learning.

    PubMed

    Heston, Jonathan B; White, Stephanie A

    2015-02-18

    Mutations in the FOXP2 transcription factor cause an inherited speech and language disorder, but how FoxP2 contributes to learning of these vocal communication signals remains unclear. FoxP2 is enriched in corticostriatal circuits of both human and songbird brains. Experimental knockdown of this enrichment in song control neurons of the zebra finch basal ganglia impairs tutor song imitation, indicating that adequate FoxP2 levels are necessary for normal vocal learning. In unmanipulated birds, vocal practice acutely downregulates FoxP2, leading to increased vocal variability and dynamic regulation of FoxP2 target genes. To determine whether this behavioral regulation is important for song learning, here, we used viral-driven overexpression of FoxP2 to counteract its downregulation. This manipulation disrupted the acute effects of song practice on vocal variability and caused inaccurate song imitation. Together, these findings indicate that dynamic behavior-linked regulation of FoxP2, rather than absolute levels, is critical for vocal learning.

  16. Blood Mercury Levels of Zebra Finches Are Heritable: Implications for the Evolution of Mercury Resistance

    PubMed Central

    Buck, Kenton A.; Varian-Ramos, Claire W.; Cristol, Daniel A.; Swaddle, John P.

    2016-01-01

    Mercury is a ubiquitous metal contaminant that negatively impacts reproduction of wildlife and has many other sub-lethal effects. Songbirds are sensitive bioindicators of mercury toxicity and may suffer population declines as a result of mercury pollution. Current predictions of mercury accumulation and biomagnification often overlook possible genetic variation in mercury uptake and elimination within species and the potential for evolution in affected populations. We conducted a study of dietary mercury exposure in a model songbird species, maintaining a breeding population of zebra finches (Taeniopygia guttata) on standardized diets ranging from 0.0–2.4 μg/g methylmercury. We applied a quantitative genetics approach to examine patterns of variation and heritability of mercury accumulation within dietary treatments using a method of mixed effects modeling known as the 'animal model'. Significant variation in blood mercury accumulation existed within each treatment for birds exposed at the same dietary level; moreover, this variation was highly repeatable for individuals. We observed substantial genetic variation in blood mercury accumulation for birds exposed at intermediate dietary concentrations. Taken together, this is evidence that genetic variation for factors affecting blood mercury accumulation could be acted on by selection. If similar heritability for mercury accumulation exists in wild populations, selection could result in genetic differentiation for populations in contaminated locations, with possible consequences for mercury biomagnification in food webs. PMID:27668745

  17. Song discrimination learning in zebra finches induces highly divergent responses to novel songs.

    PubMed

    Verzijden, Machteld N; Etman, Eric; van Heijningen, Caroline; van der Linden, Marianne; ten Cate, Carel

    2007-01-22

    Perceptual biases can shape the evolution of signal form. Understanding the origin and direction of such biases is therefore crucial for understanding signal evolution. Many animals learn about species-specific signals. Discrimination learning using simple stimuli varying in one dimension (e.g. amplitude, wavelength) can result in perceptual biases with preferences for specific novel stimuli, depending on the stimulus dimensions. We examine how this translates to discrimination learning involving complex communication signals; birdsongs. Zebra finches (Taeniopygia guttata) were trained to discriminate between two artificial songs, using a Go/No-Go procedure. The training songs in experiment 1 differed in the number of repeats of a particular element. The songs in experiment 2 differed in the position of an odd element in a series of repeated elements. We examined generalization patterns by presenting novel songs with more or fewer repeated elements (experiment 1), or with the odd element earlier or later in the repeated element sequence (experiment 2). Control birds were trained with only one song. The generalization curves obtained from (i) control birds, (ii) experimental birds in experiment 1, and (iii) experimental birds in experiment 2 showed large and systematic differences from each other. Birds in experiment 1, but not 2, responded more strongly to specific novel songs than to training songs, showing 'peak shift'. The outcome indicates that learning about communication signals may give rise to perceptual biases that may drive signal evolution. PMID:17148259

  18. Dynamic role of postsynaptic caspase-3 and BIRC4 in zebra finch song response habituation

    PubMed Central

    Huesmann, Graham R.; Clayton, David F.

    2007-01-01

    Summary Activation of the protease caspase-3 is commonly thought to cause apoptotic cell death. Here we show that caspase-3 activity is regulated at postsynaptic sites in brain following stimuli associated with memory (neural activation and subsequent response habituation) instead of cell death. In the zebra finch auditory forebrain, the concentration of caspase-3 active sites increases briefly within minutes after exposure to tape-recorded birdsong. With confocal and immunoelectron microscopy, we localize the activated enzyme to dendritic spines. The activated caspase-3 protein is present even in unstimulated brain but bound to an endogenous inhibitor, BIRC4 (xIAP), suggesting a mechanism for rapid release and sequestering at specific synaptic sites. Caspase-3 activity is necessary to consolidate a persistent physiological trace of the song stimulus, as demonstrated using pharmacological interference and the zenk gene habituation assay. Thus the brain appears to have adapted a core component of cell death machinery to serve a unique role in learning and memory. PMID:17178408

  19. Long-term effects of manipulated natal brood size on metabolic rate in zebra finches.

    PubMed

    Verhulst, Simon; Holveck, Marie-Jeanne; Riebel, Katharina

    2006-09-22

    Long-term effects of developmental conditions on health, longevity and other fitness components in humans are drawing increasing attention. In evolutionary ecology, such effects are of similar importance because of their role in the trade-off between quantity and quality of offspring. The central role of energy consumption is well documented for some long-term health effects in humans (e.g. obesity), but little is known of the long-term effects of rearing conditions on energy requirements later in life. We manipulated the rearing conditions in zebra finches (Taeniopygia guttata) using brood size manipulation and cross-fostering. It has previously been shown in this species that being reared in a large brood has negative fitness consequences, and that such effects are stronger in daughters than in sons. We show that, independent of mass, standard metabolic rate of 1-year-old birds was higher when they had been reared in a large brood, and this is to our knowledge the first demonstration of such an effect. Furthermore, the brood size effect was stronger in daughters than in sons. This suggests that metabolic efficiency may play a role in mediating the long-term fitness consequences of rearing conditions. PMID:17148435

  20. Long-term effects of manipulated natal brood size on metabolic rate in zebra finches

    PubMed Central

    Verhulst, Simon; Holveck, Marie-Jeanne; Riebel, Katharina

    2006-01-01

    Long-term effects of developmental conditions on health, longevity and other fitness components in humans are drawing increasing attention. In evolutionary ecology, such effects are of similar importance because of their role in the trade-off between quantity and quality of offspring. The central role of energy consumption is well documented for some long-term health effects in humans (e.g. obesity), but little is known of the long-term effects of rearing conditions on energy requirements later in life. We manipulated the rearing conditions in zebra finches (Taeniopygia guttata) using brood size manipulation and cross-fostering. It has previously been shown in this species that being reared in a large brood has negative fitness consequences, and that such effects are stronger in daughters than in sons. We show that, independent of mass, standard metabolic rate of 1-year-old birds was higher when they had been reared in a large brood, and this is to our knowledge the first demonstration of such an effect. Furthermore, the brood size effect was stronger in daughters than in sons. This suggests that metabolic efficiency may play a role in mediating the long-term fitness consequences of rearing conditions. PMID:17148435

  1. Heterologous Synapsis and Crossover Suppression in Heterozygotes for a Pericentric Inversion in the Zebra Finch.

    PubMed

    del Priore, Lucía; Pigozzi, María I

    2015-01-01

    In the zebra finch, 2 alternative morphs regarding centromere position were described for chromosome 6. This polymorphism was interpreted to be the result of a pericentric inversion, but other causes of the centromere repositioning were not ruled out. We used immunofluorescence localization to examine the distribution of MLH1 foci on synaptonemal complexes to test the prediction that pericentric inversions cause synaptic irregularities and/or crossover suppression in heterozygotes. We found complete suppression of crossing over in the region involved in the rearrangement in male and female heterozygotes. In contrast, the same region showed high levels of crossing over in homozygotes for the acrocentric form of this chromosome. No inversion loops or synaptic irregularities were detected along bivalent 6 in heterozygotes suggesting that heterologous pairing is achieved during zygotene or early pachytene. Altogether these findings strongly indicate that the polymorphic chromosome 6 originated by a pericentric inversion. Since inversions are common rearrangements in karyotypic evolution in birds, it seems likely that early heterologous pairing could help to fix these rearrangements, preventing crossing overs in heterozygotes and their deleterious effects on fertility.

  2. Increased fat catabolism sustains water balance during fasting in zebra finches.

    PubMed

    Rutkowska, Joanna; Sadowska, Edyta T; Cichoń, Mariusz; Bauchinger, Ulf

    2016-09-01

    Patterns of physiological flexibility in response to fasting are well established, but much less is known about the contribution of water deprivation to the observed effects. We investigated body composition and energy and water budget in three groups of zebra finches: birds with access to food and water, food-deprived birds having access to drinking water and food-and-water-deprived birds. Animals were not stimulated by elevated energy expenditure and they were in thermoneutral conditions; thus, based on previous studies, water balance of fasting birds was expected to be maintained by increased catabolism of proteins. In contrast to this expectation, we found that access to water did not prevent reduction of proteinaceous tissue, but it saved fat reserves of the fasting birds. Thus, water balance of birds fasting without access to water seemed to be maintained by elevated fat catabolism, which generated 6 times more metabolic water compared with that in birds that had access to water. Therefore, we revise currently established views and propose fat to serve as the primary source for metabolic water production. Previously assumed increased protein breakdown for maintenance of water budget would occur if fat stores were depleted or if fat catabolism reached its upper limits due to high energy demands. PMID:27582561

  3. The Forebrain Song System Mediates Predictive Call Timing in Female and Male Zebra Finches.

    PubMed

    Benichov, Jonathan I; Benezra, Sam E; Vallentin, Daniela; Globerson, Eitan; Long, Michael A; Tchernichovski, Ofer

    2016-02-01

    The dichotomy between vocal learners and non-learners is a fundamental distinction in the study of animal communication. Male zebra finches (Taeniopygia guttata) are vocal learners that acquire a song resembling their tutors', whereas females can only produce innate calls. The acoustic structure of short calls, produced by both males and females, is not learned. However, these calls can be precisely coordinated across individuals. To examine how birds learn to synchronize their calls, we developed a vocal robot that exchanges calls with a partner bird. Because birds answer the robot with stereotyped latencies, we could program it to disrupt each bird's responses by producing calls that are likely to coincide with the bird's. Within minutes, the birds learned to avoid this disruptive masking (jamming) by adjusting the timing of their responses. Notably, females exhibited greater adaptive timing plasticity than males. Further, when challenged with complex rhythms containing jamming elements, birds dynamically adjusted the timing of their calls in anticipation of jamming. Blocking the song system cortical output dramatically reduced the precision of birds' response timing and abolished their ability to avoid jamming. Surprisingly, we observed this effect in both males and females, indicating that the female song system is functional rather than vestigial. We suggest that descending forebrain projections, including the song-production pathway, function as a general-purpose sensorimotor communication system. In the case of calls, it enables plasticity in vocal timing to facilitate social interactions, whereas in the case of songs, plasticity extends to developmental changes in vocal structure. PMID:26774786

  4. Sex-specific effects of handling time on an index of immune activity in zebra finches.

    PubMed

    Berzins, Lisha L; Tilman-Schindel, Elinor; Burness, Gary

    2008-01-01

    Recently, there has been considerable interest in the role of the immune system in shaping life-history evolution, sexual selection strategies, and indexes of individual quality. The most frequently used assay of immune function, particularly in avian field studies, is the phytohemagglunitin (PHA) skin test. PHA is injected subcutaneously into the wing web, and the magnitude of the resultant swelling has traditionally been interpreted as an index of an individual's cell-mediated immunocompetence. The test follows one of two protocols: the traditional two-wing injection protocol, with one wing web injected with PHA and the other with phosphate-buffered saline (PBS), or the simplified one-wing protocol that omits the PBS injection. In this technical comment, we alert researchers to the importance of considering handling time when performing the PHA test. We show that zebra finches (Taeniopygia guttata) subjected to the two-wing protocol had a lower wing-web swelling than individuals injected in one wing. In males, handling time explained over 50% of the variation in an individual's skin swelling response; females were relatively unaffected by handling time. We suggest that caution should be exercised when comparing the magnitude of wing-web swelling across studies in which the alternate protocol was followed. In addition, the recording of handling time, and its inclusion in subsequent statistical analyses, may aid in the detection of subtle differences across treatments.

  5. Contractile activity of the pectoralis in the zebra finch according to mode and velocity of flap-bounding flight.

    PubMed

    Tobalske, Bret W; Puccinelli, Lisa A; Sheridan, David C

    2005-08-01

    We studied flying zebra finch (Taeniopygia guttata, N = 12), to provide a new test of a long-standing ;fixed-gear' hypothesis that flap-bounding birds use only intermittent non-flapping phases, instead of variation in muscle activity, to vary mechanical power output in flight. Using sonomicrometry and electromyography, we measured in vivo fascicle length and neuromuscular recruitment in the pectoralis as the birds flew in different flight modes (level, ascending, descending; mean velocity 1.6+/-0.3 m s(-1)) and across velocities in a new, variable-speed wind tunnel (0-12 m s(-1)). Synchronized high-speed digital video (250 Hz) provided a record of wing kinematics. Flight mode had a significant effect upon pectoralis strain, strain rate, fractional shortening and the relative timing of muscle activity (onset, offset and duration). Among flight velocities, we observed significant variation in pectoralis strain, fractional lengthening and shortening, strain rate, relative electromyographic (EMG) amplitude, and EMG duration and offset. In particular, variation in strain rate and relative EMG amplitude indicates that the fixed-gear hypothesis should be rejected. Instead, it appears that zebra finch vary work and power output within wingbeats by modulating muscle contractile behavior and between wingbeats using intermittent bounds. Muscle activity patterns and wing kinematics were similar between free flight and wind tunnel flight at similar speeds. Comparing flights with and without surgically implanted transducers and electrodes, zebra finch exhibited a reduction in maximum velocity (from 14 to 12 m s(-1)) and a significant increase in wingbeat frequency and percent time flapping. This identifies a potential limitation of in vivo flight measurements, and similar studies of bird flight should, therefore, include measurements of the extent to which flight performance is compromised by experimental protocol.

  6. Audience effect alters male mating preferences in zebra finches (Taeniopygia guttata).

    PubMed

    Dubois, Frédérique; Belzile, Alexandra

    2012-01-01

    The social environment of animals strongly influences the mating preferences of both the choosing and the observing individuals. Notably, there is recent evidence that polygamous males decrease their selectivity when being observed by competitors in order to direct their rivals' attention away from their true interest and, consequently, reduce sperm competition risk. Yet, other mechanisms, whose importance remains unexplored, could induce similar effects. In monogamous species with mutual choice, particularly, if males adjust their selectivity according to the risk of being rejected by their preferred mate, they should as well become less selective when potential rivals are present. Here, we investigated whether the presence of bystanders modifies male mating preferences when the risk of sperm competition is low, by carrying out mate-choice experiments with male zebra finches (Taeniopygia guttata) whose preferences for two females were measured twice: with and without an audience. We found that the presence of potential rivals had no effect on the males' choosiness. However, with an audience, they spent more time with the female that was considered as the less attractive one in the control condition. These findings support the hypothesis that monogamous males alter their mate choice decisions in the presence of a male audience to reduce the risk of remaining unpaired. Thus, our results indicate that several explanations can account for the changes in male preferences due to the presence of competitors and highlight the importance of assessing the relative role of each mechanism potentially involved, to be able to make conclusions about the effect of an audience on signal evolution.

  7. Effects of acute corticosterone treatment on partner preferences in male and female zebra finches (Taeniopygia guttata).

    PubMed

    LaPlante, Kimberly A; Huremovic, Enida; Tomaszycki, Michelle L

    2014-04-01

    Stress alters physiology and behavior across species. Most research on the effects of stress on behavior uses chronic stressors, and most are correlational. The effects of acute stressors on physiology and behavior have been mixed. Here, we use zebra finches, a highly gregarious species that forms long-term pair bonds, to test the effects of an acute corticosterone (CORT) on opposite-sex partner preferences over a same-sex individual or a group (the latter is a highly appealing option). We had two competing hypotheses. First, we predicted that acute CORT would alter preferences for the opposite sex bird in both conditions in both sexes. However, since there is a sex difference in the effects of CORT on partner preferences in voles, these effects may be more pronounced in males than in females. To test our hypotheses, we administered 2 doses of CORT (10μg and 20μg) or vehicle (control) using a repeated measures design. In the male vs. female test, there was a significant Sex by Treatment interaction, such that in males, 10μg CORT increased preferences for a female over the male compared to when these same males were treated with saline at baseline. There were no effects of treatment in females. In the opposite-sex vs. group condition, there was an overall effect of Treatment, such that the 10μg dose increased preference for the opposite-sex individual over both saline treatments, regardless of sex. These findings further our understanding of the effects of an acute stressor on sexual partner preferences.

  8. Audience Effect Alters Male Mating Preferences in Zebra Finches (Taeniopygia guttata)

    PubMed Central

    Dubois, Frédérique; Belzile, Alexandra

    2012-01-01

    The social environment of animals strongly influences the mating preferences of both the choosing and the observing individuals. Notably, there is recent evidence that polygamous males decrease their selectivity when being observed by competitors in order to direct their rivals’ attention away from their true interest and, consequently, reduce sperm competition risk. Yet, other mechanisms, whose importance remains unexplored, could induce similar effects. In monogamous species with mutual choice, particularly, if males adjust their selectivity according to the risk of being rejected by their preferred mate, they should as well become less selective when potential rivals are present. Here, we investigated whether the presence of bystanders modifies male mating preferences when the risk of sperm competition is low, by carrying out mate-choice experiments with male zebra finches (Taeniopygia guttata) whose preferences for two females were measured twice: with and without an audience. We found that the presence of potential rivals had no effect on the males’ choosiness. However, with an audience, they spent more time with the female that was considered as the less attractive one in the control condition. These findings support the hypothesis that monogamous males alter their mate choice decisions in the presence of a male audience to reduce the risk of remaining unpaired. Thus, our results indicate that several explanations can account for the changes in male preferences due to the presence of competitors and highlight the importance of assessing the relative role of each mechanism potentially involved, to be able to make conclusions about the effect of an audience on signal evolution. PMID:22916298

  9. Effect of laying sequence on egg mercury in captive zebra finches: an interpretation considering individual variation.

    PubMed

    Ou, Langbo; Varian-Ramos, Claire W; Cristol, Daniel A

    2015-08-01

    Bird eggs are used widely as noninvasive bioindicators for environmental mercury availability. Previous studies, however, have found varying relationships between laying sequence and egg mercury concentrations. Some studies have reported that the mercury concentration was higher in first-laid eggs or declined across the laying sequence, whereas in other studies mercury concentration was not related to egg order. Approximately 300 eggs (61 clutches) were collected from captive zebra finches dosed throughout their reproductive lives with methylmercury (0.3 μg/g, 0.6 μg/g, 1.2 μg/g, or 2.4 μg/g wet wt in diet); the total mercury concentration (mean ± standard deviation [SD] dry wt basis) of their eggs was 7.03 ± 1.38 μg/g, 14.15 ± 2.52 μg/g, 26.85 ± 5.85 μg/g, and 49.76 ± 10.37 μg/g, respectively (equivalent to fresh wt egg mercury concentrations of 1.24 μg/g, 2.50 μg/g, 4.74 μg/g, and 8.79 μg/g). The authors observed a significant decrease in the mercury concentration of successive eggs when compared with the first egg and notable variation between clutches within treatments. The mercury level of individual females within and among treatments did not alter this relationship. Based on the results, sampling of a single egg in each clutch from any position in the laying sequence is sufficient for purposes of population risk assessment, but it is not recommended as a proxy for individual female exposure or as an estimate of average mercury level within the clutch.

  10. Experimental exposure to urban and pink noise affects brain development and song learning in zebra finches (Taenopygia guttata).

    PubMed

    Potvin, Dominique A; Curcio, Michael T; Swaddle, John P; MacDougall-Shackleton, Scott A

    2016-01-01

    Recently, numerous studies have observed changes in bird vocalizations-especially song-in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers' songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats. PMID:27602270

  11. Food, stress, and reproduction: short-term fasting alters endocrine physiology and reproductive behavior in the zebra finch.

    PubMed

    Lynn, Sharon E; Stamplis, Teresa B; Barrington, William T; Weida, Nicholas; Hudak, Casey A

    2010-07-01

    Stress is thought to be a potent suppressor of reproduction. However, the vast majority of studies focus on the relationship between chronic stress and reproductive suppression, despite the fact that chronic stress is rare in the wild. We investigated the role of fasting in altering acute stress physiology, reproductive physiology, and reproductive behavior of male zebra finches (Taeniopygia guttata) with several goals in mind. First, we wanted to determine if acute fasting could stimulate an increase in plasma corticosterone and a decrease in corticosteroid binding globulin (CBG) and testosterone. We then investigated whether fasting could alter expression of undirected song and courtship behavior. After subjecting males to fasting periods ranging from 1 to 10h, we collected plasma to measure corticosterone, CBG, and testosterone. We found that plasma corticosterone was elevated, and testosterone was decreased after 4, 6, and 10h of fasting periods compared with samples collected from the same males during nonfasted (control) periods. CBG was lower than control levels only after 10h of fasting. We also found that, coincident with these endocrine changes, males sang less and courted females less vigorously following short-term fasting relative to control conditions. Our data demonstrate that acute fasting resulted in rapid changes in endocrine physiology consistent with hypothalamo-pituitary-adrenal axis activation and hypothalamo-pituitary-gonadal axis deactivation. Fasting also inhibited reproductive behavior. We suggest that zebra finches exhibit physiological and behavioral flexibility that makes them an excellent model system for studying interactions of acute stress and reproduction.

  12. Experimental exposure to urban and pink noise affects brain development and song learning in zebra finches (Taenopygia guttata)

    PubMed Central

    Curcio, Michael T.; Swaddle, John P.; MacDougall-Shackleton, Scott A.

    2016-01-01

    Recently, numerous studies have observed changes in bird vocalizations—especially song—in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers’ songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats. PMID:27602270

  13. Acoustic Communication and Sound Degradation: How Do the Individual Signatures of Male and Female Zebra Finch Calls Transmit over Distance?

    PubMed Central

    Mouterde, Solveig C.; Theunissen, Frédéric E.; Elie, Julie E.; Vignal, Clémentine; Mathevon, Nicolas

    2014-01-01

    Background Assessing the active space of the various types of information encoded by songbirds' vocalizations is important to address questions related to species ecology (e.g. spacing of individuals), as well as social behavior (e.g. territorial and/or mating strategies). Up to now, most of the previous studies have investigated the degradation of species-specific related information (species identity), and there is a gap of knowledge of how finer-grained information (e.g. individual identity) can transmit through the environment. Here we studied how the individual signature coded in the zebra finch long distance contact call degrades with propagation. Methodology We performed sound transmission experiments of zebra finches' distance calls at various propagation distances. The propagated calls were analyzed using discriminant function analyses on a set of analytical parameters describing separately the spectral and temporal envelopes, as well as on a complete spectrographic representation of the signals. Results/Conclusion We found that individual signature is remarkably resistant to propagation as caller identity can be recovered even at distances greater than a hundred meters. Male calls show stronger discriminability at long distances than female calls, and this difference can be explained by the more pronounced frequency modulation found in their calls. In both sexes, individual information is carried redundantly using multiple acoustical features. Interestingly, features providing the highest discrimination at short distances are not the same ones that provide the highest discrimination at long distances. PMID:25061795

  14. Experimental exposure to urban and pink noise affects brain development and song learning in zebra finches (Taenopygia guttata).

    PubMed

    Potvin, Dominique A; Curcio, Michael T; Swaddle, John P; MacDougall-Shackleton, Scott A

    2016-01-01

    Recently, numerous studies have observed changes in bird vocalizations-especially song-in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers' songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats.

  15. The interplay of within-species perceptual predispositions and experience during song ontogeny in zebra finches (Taeniopygia guttata)

    PubMed Central

    ter Haar, Sita M.; Kaemper, Wiebke; Stam, Koen; Levelt, Clara C.; ten Cate, Carel

    2014-01-01

    Vocal acquisition in songbirds and humans shows many similarities, one of which is that both involve a combination of experience and perceptual predispositions. Among languages some speech sounds are shared, while others are not. This could reflect a predisposition in young infants for learning some speech sounds over others, which combines with exposure-based learning. Similarly, in songbirds, some sounds are common across populations, while others are more specific to populations or individuals. We examine whether this is also due to perceptual preferences for certain within-species element types in naive juvenile male birds, and how such preferences interact with exposure to guide subsequent song learning. We show that young zebra finches lacking previous song exposure perceptually prefer songs with more common zebra finch song element types over songs with less common elements. Next, we demonstrate that after subsequent tutoring, birds prefer tutor songs regardless of whether these contain more common or less common elements. In adulthood, birds tutored with more common elements showed a higher song similarity to their tutor song, indicating that the early bias influenced song learning. Our findings help to understand the maintenance of similarities and the presence of differences among birds' songs, their dialects and human languages. PMID:25320162

  16. Experimental exposure to urban and pink noise affects brain development and song learning in zebra finches (Taenopygia guttata)

    PubMed Central

    Curcio, Michael T.; Swaddle, John P.; MacDougall-Shackleton, Scott A.

    2016-01-01

    Recently, numerous studies have observed changes in bird vocalizations—especially song—in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers’ songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats.

  17. Sex-biased investment in yolk androgens depends on female quality and laying order in zebra finches (Taeniopygia guttata)

    NASA Astrophysics Data System (ADS)

    Gilbert, Lucy; Rutstein, Alison N.; Hazon, Neil; Graves, Jefferson A.

    2005-04-01

    The Trivers-Willard hypothesis predicts sex biases in parental investment according to parental condition. In addition, parents may need to sex bias their investment if there is an asymmetry between the sexes in offspring fitness under different conditions. For studying maternal differential investment, egg resources are ideal subjects because they are self contained and allocated unequivocally by the female. Recent studies show that yolk androgens can be beneficial to offspring, so here we test for sex-biased investment with maternal investment of yolk testosterone (T) in zebra finch (Taeniopygia guttata) eggs. From the Trivers-Willard hypothesis, we predicted females to invest more in male eggs in optimum circumstances (e.g. good-condition mother, early-laid egg), and more in female eggs under suboptimal conditions (e.g. poor-condition mother, late-laid egg). This latter prediction is also because in this species there is a female nestling disadvantage in poor conditions and we expected mothers to help compensate for this in female eggs. Indeed, we found more yolk T in female than male eggs. Moreover, in accordance with our predictions, yolk T in male eggs increased with maternal quality relative to female eggs, and decreased with laying order relative to female eggs. This supports our predictions for the different needs and value of male and female offspring in zebra finches. Our results support the idea that females may use yolk androgens as a tool to adaptively manipulate the inequalities between different nestlings.

  18. A genome-wide search for eigenetically regulated genes in zebra finch using MethylCap-seq and RNA-seq

    PubMed Central

    Steyaert, Sandra; Diddens, Jolien; Galle, Jeroen; De Meester, Ellen; De Keulenaer, Sarah; Bakker, Antje; Sohnius-Wilhelmi, Nina; Frankl-Vilches, Carolina; Van der Linden, Annemie; Van Criekinge, Wim; Vanden Berghe, Wim; De Meyer, Tim

    2016-01-01

    Learning and memory formation are known to require dynamic CpG (de)methylation and gene expression changes. Here, we aimed at establishing a genome-wide DNA methylation map of the zebra finch genome, a model organism in neuroscience, as well as identifying putatively epigenetically regulated genes. RNA- and MethylCap-seq experiments were performed on two zebra finch cell lines in presence or absence of 5-aza-2′-deoxycytidine induced demethylation. First, the MethylCap-seq methodology was validated in zebra finch by comparison with RRBS-generated data. To assess the influence of (variable) methylation on gene expression, RNA-seq experiments were performed as well. Comparison of RNA-seq and MethylCap-seq results showed that at least 357 of the 3,457 AZA-upregulated genes are putatively regulated by methylation in the promoter region, for which a pathway analysis showed remarkable enrichment for neurological networks. A subset of genes was validated using Exon Arrays, quantitative RT-PCR and CpG pyrosequencing on bisulfite-treated samples. To our knowledge, this study provides the first genome-wide DNA methylation map of the zebra finch genome as well as a comprehensive set of genes of which transcription is under putative methylation control. PMID:26864856

  19. Cannabinoid mitigation of neuronal morphological change important to development and learning: insight from a zebra finch model of psychopharmacology.

    PubMed

    Soderstrom, Ken; Gilbert, Marcoita T

    2013-03-19

    Normal CNS development proceeds through late-postnatal stages of adolescent development. The activity-dependence of this development underscores the significance of CNS-active drug exposure prior to completion of brain maturation. Exogenous modulation of signaling important in regulating normal development is of particular concern. This mini-review presents a summary of the accumulated behavioral, physiological and biochemical evidence supporting such a key regulatory role for endocannabinoid signaling during late-postnatal CNS development. Our focus is on the data obtained using a unique zebra finch model of developmental psychopharmacology. This animal has allowed investigation of neuronal morphological effects essential to establishment and maintenance of neural circuitry, including processes related to synaptogenesis and dendritic spine dynamics. Altered neurophysiology that follows exogenous cannabinoid exposure during adolescent development has the potential to persistently alter cognition, learning and memory.

  20. Sex differences in the ventral paleostriatum of the zebra finch: origin of the cholinergic innervation of the song control nuclei.

    PubMed

    Sakaguchi, H; Li, R; Taniguchi, I

    2000-08-21

    The two main song control nuclei in the forebrain of zebra finches, the higher vocal center (HVC) and the robust nucleus of the archistriatum (RA), are sexually dimorphic at many levels of their neural circuitry. These nuclei receive their cholinergic innervation from the ventral paleostriatum (VP), which is homologous to portions of the mammalian basal forebrain. We compared the cholinergic neurons in the VP between the sexes using choline acetyltransferase (ChAT) immunohistochemistry. Both the size and density of the ChAT-immunoreactive somata in areas of the VP that project to the HVC or RA in males were significantly larger than those in females. These sex differences in the VP may be reflected in the sex differences of behaviors such as song perception and production.

  1. Sex-specific effects of maternal immunization on yolk antibody transfer and offspring performance in zebra finches

    PubMed Central

    Martyka, Rafał; Rutkowska, Joanna; Cichoń, Mariusz

    2011-01-01

    Trans-generational antibody transfer constitutes an important mechanism by which mothers may enhance offspring resistance to pathogens. Thus, differential antibody deposition may potentially allow a female to differentiate offspring performance. Here, we examined whether maternal immunization with sheep red blood cells (SRBC) prior to egg laying affects sex-specific yolk antibody transfer and sex-specific offspring performance in zebra finches (Taeniopygia guttata). We showed that immunized mothers deposit anti-SRBC antibodies into the eggs depending on embryo sex and laying order, and that maternal exposure to SRBC positively affects the body size of female, but not male offspring. This is the first study reporting sex-specific consequences of maternal immunization on offspring performance, and suggests that antibody transfer may constitute an adaptive mechanism of maternal favouritism. PMID:20667842

  2. Features of the Retinotopic Representation in the Visual Wulst of a Laterally Eyed Bird, the Zebra Finch (Taeniopygia guttata)

    PubMed Central

    Michael, Neethu; Löwel, Siegrid; Bischof, Hans-Joachim

    2015-01-01

    The visual wulst of the zebra finch comprises at least two retinotopic maps of the contralateral eye. As yet, it is not known how much of the visual field is represented in the wulst neuronal maps, how the organization of the maps is related to the retinal architecture, and how information from the ipsilateral eye is involved in the activation of the wulst. Here, we have used autofluorescent flavoprotein imaging and classical anatomical methods to investigate such characteristics of the most posterior map of the multiple retinotopic representations. We found that the visual wulst can be activated by visual stimuli from a large part of the visual field of the contralateral eye. Horizontally, the visual field representation extended from -5° beyond the beak tip up to +125° laterally. Vertically, a small strip from -10° below to about +25° above the horizon activated the visual wulst. Although retinal ganglion cells had a much higher density around the fovea and along a strip extending from the fovea towards the beak tip, these areas were not overrepresented in the wulst map. The wulst area activated from the foveal region of the ipsilateral eye, overlapped substantially with the middle of the three contralaterally activated regions in the visual wulst, and partially with the other two. Visual wulst activity evoked by stimulation of the frontal visual field was stronger with contralateral than with binocular stimulation. This confirms earlier electrophysiological studies indicating an inhibitory influence of the activation of the ipsilateral eye on wulst activity elicited by stimulating the contralateral eye. The lack of a foveal overrepresentation suggests that identification of objects may not be the primary task of the zebra finch visual wulst. Instead, this brain area may be involved in the processing of visual information necessary for spatial orientation. PMID:25853253

  3. Daily behaviour can differ between colour morphs of the same species: a study on circadian activity behaviour of grey and pied zebra finches.

    PubMed

    Mishra, Ila; Trivedi, Amit Kumar; Kumar, Vinod

    2014-05-01

    To investigate if the plumage colour mutation relates to circadian activity behaviour in the zebra finch, Taeniopygia guttata, wild type grey and pied mutant males were sequentially subjected for three weeks each to 12 h light:12 h darkness (12L:12D) and constant dim light (LL(dim)) condition. During the first 3 h of the 12 h day, pied finches were significantly greater active than grey finches. Also, as compared to grey, pied finches had longer activity duration in the day, with early activity onsets and late activity offsets. This was changed under free-running condition (LL(dim)), when the activity later in the subjective day (clock hour 9 and 11) was significantly greater in grey than in pied finches.Two colour morphs differed in daily activity profile, but not in the total daily activity or circadian rhythm period. Results suggest that greyzebra finches represent late chronotype, and could perhaps be better adapted to a seemingly stressful environment, such as low intensity LL(dim) in the present study.

  4. Frequency-range discriminations and absolute pitch in black-capped chickadees (Poecile atricapillus), mountain chickadees (Poecile gambeli), and zebra finches (Taeniopygia guttata).

    PubMed

    Lee, Tiffany T Y; Charrier, Isabelle; Bloomfield, Laurie L; Weisman, Ronald G; Sturdy, Christopher B

    2006-08-01

    The acoustic frequency ranges in birdsongs provide important absolute pitch cues for the recognition of conspecifics. Black-capped chickadees (Poecile atricapillus), mountain chickadees (Poecile gambeli), and zebra finches (Taeniopygia guttata) were trained to sort tones contiguous in frequency into 8 ranges on the basis of associations between response to the tones in each range and reward. All 3 species acquired accurate frequency-range discriminations, but zebra finches acquired the discrimination in fewer trials and to a higher standard than black-capped or mountain chickadees, which did not differ appreciably in the discrimination. Chickadees' relatively poorer accuracy was traced to poorer discrimination of tones in the higher frequency ranges. During transfer tests, the discrimination generalized to novel tones when the training tones were included, but not when they were omitted.

  5. Frequency-range discriminations and absolute pitch in black-capped chickadees (Poecile atricapillus), mountain chickadees (Poecile gambeli), and zebra finches (Taeniopygia guttata).

    PubMed

    Lee, Tiffany T Y; Charrier, Isabelle; Bloomfield, Laurie L; Weisman, Ronald G; Sturdy, Christopher B

    2006-08-01

    The acoustic frequency ranges in birdsongs provide important absolute pitch cues for the recognition of conspecifics. Black-capped chickadees (Poecile atricapillus), mountain chickadees (Poecile gambeli), and zebra finches (Taeniopygia guttata) were trained to sort tones contiguous in frequency into 8 ranges on the basis of associations between response to the tones in each range and reward. All 3 species acquired accurate frequency-range discriminations, but zebra finches acquired the discrimination in fewer trials and to a higher standard than black-capped or mountain chickadees, which did not differ appreciably in the discrimination. Chickadees' relatively poorer accuracy was traced to poorer discrimination of tones in the higher frequency ranges. During transfer tests, the discrimination generalized to novel tones when the training tones were included, but not when they were omitted. PMID:16893259

  6. Multiple Visual Field Representations in the Visual Wulst of a Laterally Eyed Bird, the Zebra Finch (Taeniopygia guttata)

    PubMed Central

    2016-01-01

    The visual wulst is the telencephalic target of the avian thalamofugal visual system. It contains several retinotopically organised representations of the contralateral visual field. We used optical imaging of intrinsic signals, electrophysiological recordings, and retrograde tracing with two fluorescent tracers to evaluate properties of these representations in the zebra finch, a songbird with laterally placed eyes. Our experiments revealed that there is some variability of the neuronal maps between individuals and also concerning the number of detectable maps. It was nonetheless possible to identify three different maps, a posterolateral, a posteromedial, and an anterior one, which were quite constant in their relation to each other. The posterolateral map was in contrast to the two others constantly visible in each successful experiment. The topography of the two other maps was mirrored against that map. Electrophysiological recordings in the anterior and the posterolateral map revealed that all units responded to flashes and to moving bars. Mean directional preferences as well as latencies were different between neurons of the two maps. Tracing experiments confirmed previous reports on the thalamo-wulst connections and showed that the anterior and the posterolateral map receive projections from separate clusters within the thalamic nuclei. Maps are connected to each other by wulst intrinsic projections. Our experiments confirm that the avian visual wulst contains several separate retinotopic maps with both different physiological properties and different thalamo-wulst afferents. This confirms that the functional organization of the visual wulst is very similar to its mammalian equivalent, the visual cortex. PMID:27139912

  7. Behavioral effects of progesterone on pair bonding and partner preference in the female zebra finch (Taeniopygia guttata).

    PubMed

    Smiley, Kristina O; Vahaba, Daniel M; Tomaszycki, Michelle L

    2012-06-01

    Progesterone is a sex steroid known to be involved in reproduction, but its role in pair relationships is not well understood. This study explored the effects of exogenous progesterone (P4) on courtship and pairing behaviors in female zebra finches (Taeniopygia guttata) in two separate experiments: the first focused on courtship and initial pair formation and the second examined the effects on pair maintenance. In these experiments, we tested the hypothesis that P4 increases pairing behaviors and consequently influences their partner preference. In Experiment 1, animals engaged in significantly more pairing behaviors when they were treated with P4 than when they received the vehicle. However, this effect was not partner-specific, since the association index (a marker for female partner preference) did not differ between treatment conditions. In Experiment 2, females were given two weeks to form a pair and then injected with P4 or vehicle. Pairs were observed that day and the subsequent day to determine if P4 caused a decrease in mate-directed behavior and an increase in extra pair behavior. P4 did not affect the quality of the pair relationship and did not increase extra pair behavior. These results suggest that P4 influences the overall quantity of initial pairing behaviors and may slightly increase the likelihood of partner preference formation over short time courses. However, P4 does not alter a previously established bond, suggesting there are likely separate mechanisms for initial pairing behaviors and pair maintenance.

  8. Co-localization of sorting nexin 2 and androgen receptor in the song system of juvenile zebra finches.

    PubMed

    Wu, Di; Tang, Yu Ping; Wade, Juli

    2010-07-01

    Mechanisms regulating sexual differentiation of the zebra finch song system appear to include both genetic and hormonal factors. Sorting Nexin 2 (SNX2), which is involved in trafficking proteins between cellular membranes, and androgen receptor (AR) mRNA are both increased in song control nuclei of juvenile males compared to females. Here, in situ hybridization for SNX2 and immunohistochemistry for AR were used to evaluate these sexual dimorphisms in more detail. Estimates of the total number of HVC cells expressing SNX2 and AR, individually as well as together, were greater in 25-day-old males compared to females. The densities of these types of cells were generally also increased in males compared to females in HVC and Area X (or the equivalent portion of the medial striatum in females). On average, more than half of the AR+ cells co-expressed SNX2 in both brain regions. The potential, therefore, exists for both AR and SNX2 to be involved in masculinization of these two brain regions. One possibility is that they, either separately or in conjunction, enhance the action of trophic factors within the brain. PMID:20452330

  9. Male foraging efficiency, but not male problem-solving performance, influences female mating preferences in zebra finches.

    PubMed

    Chantal, Véronique; Gibelli, Julie; Dubois, Frédérique

    2016-01-01

    Experimental evidence suggests that females would prefer males with better cognitive abilities as mates. However, little is known about the traits reflecting enhanced cognitive skills on which females might base their mate-choice decisions. In particular, it has been suggested that male foraging performance could be used as an indicator of cognitive capacity, but convincing evidence for this hypothesis is still lacking. In the present study, we investigated whether female zebra finches (Taeniopygia guttata) modify their mating preferences after having observed the performance of males on a problem-solving task. Specifically, we measured the females' preferences between two males once before and once after an observation period, during which their initially preferred male was incapable of solving the task contrary to their initially less-preferred male. We also conducted a control treatment to test whether the shift in female preferences was attributable to differences between the two stimulus males in their foraging efficiency. Finally, we assessed each bird's performance in a color associative task to check whether females can discriminate among males based on their learning speed. We found that females significantly increased their preference toward the most efficient male in both treatments. Yet, there was no difference between the two treatments and we found no evidence that females assess male cognitive ability indirectly via morphological traits. Thus, our results suggest that females would not use the males' problem-solving performance as an indicator of general cognitive ability to gain indirect fitness benefits (i.e., good genes) but rather to assess their foraging efficiency and gain direct benefits.

  10. Male foraging efficiency, but not male problem-solving performance, influences female mating preferences in zebra finches

    PubMed Central

    Chantal, Véronique

    2016-01-01

    Experimental evidence suggests that females would prefer males with better cognitive abilities as mates. However, little is known about the traits reflecting enhanced cognitive skills on which females might base their mate-choice decisions. In particular, it has been suggested that male foraging performance could be used as an indicator of cognitive capacity, but convincing evidence for this hypothesis is still lacking. In the present study, we investigated whether female zebra finches (Taeniopygia guttata) modify their mating preferences after having observed the performance of males on a problem-solving task. Specifically, we measured the females’ preferences between two males once before and once after an observation period, during which their initially preferred male was incapable of solving the task contrary to their initially less-preferred male. We also conducted a control treatment to test whether the shift in female preferences was attributable to differences between the two stimulus males in their foraging efficiency. Finally, we assessed each bird’s performance in a color associative task to check whether females can discriminate among males based on their learning speed. We found that females significantly increased their preference toward the most efficient male in both treatments. Yet, there was no difference between the two treatments and we found no evidence that females assess male cognitive ability indirectly via morphological traits. Thus, our results suggest that females would not use the males’ problem-solving performance as an indicator of general cognitive ability to gain indirect fitness benefits (i.e., good genes) but rather to assess their foraging efficiency and gain direct benefits.

  11. Activation Changes in Zebra Finch (Taeniopygia guttata) Brain Areas Evoked by Alterations of the Earth Magnetic Field

    PubMed Central

    Keary, Nina; Bischof, Hans-Joachim

    2012-01-01

    Many animals are able to perceive the earth magnetic field and to use it for orientation and navigation within the environment. The mechanisms underlying the perception and processing of magnetic field information within the brain have been thoroughly studied, especially in birds, but are still obscure. Three hypotheses are currently discussed, dealing with ferromagnetic particles in the beak of birds, with the same sort of particles within the lagena organs, or describing magnetically influenced radical-pair processes within retinal photopigments. Each hypothesis is related to a well-known sensory organ and claims parallel processing of magnetic field information with somatosensory, vestibular and visual input, respectively. Changes in activation within nuclei of the respective sensory systems have been shown previously. Most of these previous experiments employed intensity enhanced magnetic stimuli or lesions. We here exposed unrestrained zebra finches to either a stationary or a rotating magnetic field of the local intensity and inclination. C-Fos was used as an activity marker to examine whether the two treatments led to differences in fourteen brain areas including nuclei of the somatosensory, vestibular and visual system. An ANOVA revealed an overall effect of treatment, indicating that the magnetic field change was perceived by the birds. While the differences were too small to be significant in most areas, a significant enhancement of activation by the rotating stimulus was found in a hippocampal subdivision. Part of the hyperpallium showed a strong, nearly significant, increase. Our results are compatible with previous studies demonstrating an involvement of at least three different sensory systems in earth magnetic field perception and suggest that these systems, probably less elaborated, may also be found in nonmigrating birds. PMID:22679515

  12. Transient and permanent effects of suboptimal incubation temperatures on growth, metabolic rate, immune function and adrenocortical responses in zebra finches.

    PubMed

    Wada, Haruka; Kriengwatana, Buddhamas; Allen, Natalie; Schmidt, Kimberly L; Soma, Kiran K; MacDougall-Shackleton, Scott A

    2015-09-01

    In birds, incubation temperature can vary by several degrees Celsius among nests of a given species. Parents may alter incubation temperature to cope with environmental conditions and/or to manipulate embryonic development, and such changes in incubation behavior could have long-lasting effects on offspring phenotype. To investigate short- and long-term effects of suboptimal incubation temperatures on survival and physiological functions in zebra finches, eggs were incubated at 36.2, 37.4 or 38.4 °C for the entire incubation period. The post-hatch environment was identical among the treatment groups. We found that hatching success was lowest in the 38.4 °C group, while post-hatch survival was lowest in the 36.2 °C group. Incubation temperature had sex-specific effects on offspring phenotype: incubation temperatures affected body mass (Mb) but not physiological parameters of males and conversely, the physiological parameters but not Mb of females. Specifically, males from the 38.4 °C group weighed significantly less than males from the 36.2 °C group from the nestling period to adulthood, whereas females from different incubation temperature groups did not differ in Mb. In contrast, females incubated at 36.2 °C had transient but significantly elevated basal metabolic rate and adrenocortical responses during the nestling and fledgling periods, whereas no treatment effect was observed in males. Innate immunity was not affected by incubation temperature in either sex. These results suggest that a 1 °C deviation from what is considered an optimal incubation temperature can lower offspring performance and offspring survival.

  13. Male foraging efficiency, but not male problem-solving performance, influences female mating preferences in zebra finches

    PubMed Central

    Chantal, Véronique

    2016-01-01

    Experimental evidence suggests that females would prefer males with better cognitive abilities as mates. However, little is known about the traits reflecting enhanced cognitive skills on which females might base their mate-choice decisions. In particular, it has been suggested that male foraging performance could be used as an indicator of cognitive capacity, but convincing evidence for this hypothesis is still lacking. In the present study, we investigated whether female zebra finches (Taeniopygia guttata) modify their mating preferences after having observed the performance of males on a problem-solving task. Specifically, we measured the females’ preferences between two males once before and once after an observation period, during which their initially preferred male was incapable of solving the task contrary to their initially less-preferred male. We also conducted a control treatment to test whether the shift in female preferences was attributable to differences between the two stimulus males in their foraging efficiency. Finally, we assessed each bird’s performance in a color associative task to check whether females can discriminate among males based on their learning speed. We found that females significantly increased their preference toward the most efficient male in both treatments. Yet, there was no difference between the two treatments and we found no evidence that females assess male cognitive ability indirectly via morphological traits. Thus, our results suggest that females would not use the males’ problem-solving performance as an indicator of general cognitive ability to gain indirect fitness benefits (i.e., good genes) but rather to assess their foraging efficiency and gain direct benefits. PMID:27635358

  14. Neighbours' Breeding Success and the Sex Ratio of Their Offspring Affect the Mate Preferences of Female Zebra Finches

    PubMed Central

    Drullion, Dominique; Dubois, Frédérique

    2011-01-01

    Several hypotheses on divorce predict that monogamous pairs should split up more frequently after a breeding failure. Yet, deviations from the expected pattern “success-stay, failure-leave” have been reported in several species. One possible explanation for these deviations would be that individuals do not use only their own breeding performance (i.e., private information) but also that of others (i.e., public information) to decide whether or not to divorce. To test this hypothesis, we investigated the relative importance of private and public information for mate choice decisions in female zebra finches (Taeniopygia guttata).We manipulated the reproductive performance of breeding pairs and measured females' preferences for their mate and the neighbouring male first following pair formation and then seven weeks later when all females had laid eggs and the young were independent. Although all females reduced their preference for their mate after a breeding failure, the decrease was significant only when the neighbouring pair had reproduced successfully. Furthermore, there was no evidence that females biased the sex ratio of their offspring according to their mate's attractiveness. On the other hand, after reproduction, both successful and unsuccessful females increased their preferences for males who had produced a larger proportion of sons. Despite the fact that other mechanisms may have also contributed to our findings, we suggest that females changed their mate preferences based on the proportion of sons produced by successful males, because offspring sex ratio reflects the male's testosterone level at the moment of fertilization and hence is an indicator of his immune condition. PMID:22216351

  15. The songbird syrinx morphome: a three-dimensional, high-resolution, interactive morphological map of the zebra finch vocal organ

    PubMed Central

    2013-01-01

    Background Like human infants, songbirds learn their species-specific vocalizations through imitation learning. The birdsong system has emerged as a widely used experimental animal model for understanding the underlying neural mechanisms responsible for vocal production learning. However, how neural impulses are translated into the precise motor behavior of the complex vocal organ (syrinx) to create song is poorly understood. First and foremost, we lack a detailed understanding of syringeal morphology. Results To fill this gap we combined non-invasive (high-field magnetic resonance imaging and micro-computed tomography) and invasive techniques (histology and micro-dissection) to construct the annotated high-resolution three-dimensional dataset, or morphome, of the zebra finch (Taeniopygia guttata) syrinx. We identified and annotated syringeal cartilage, bone and musculature in situ in unprecedented detail. We provide interactive three-dimensional models that greatly improve the communication of complex morphological data and our understanding of syringeal function in general. Conclusions Our results show that the syringeal skeleton is optimized for low weight driven by physiological constraints on song production. The present refinement of muscle organization and identity elucidates how apposed muscles actuate different syringeal elements. Our dataset allows for more precise predictions about muscle co-activation and synergies and has important implications for muscle activity and stimulation experiments. We also demonstrate how the syrinx can be stabilized during song to reduce mechanical noise and, as such, enhance repetitive execution of stereotypic motor patterns. In addition, we identify a cartilaginous structure suited to play a crucial role in the uncoupling of sound frequency and amplitude control, which permits a novel explanation of the evolutionary success of songbirds. PMID:23294804

  16. Neighbours' breeding success and the sex ratio of their offspring affect the mate preferences of female zebra finches.

    PubMed

    Drullion, Dominique; Dubois, Frédérique

    2011-01-01

    Several hypotheses on divorce predict that monogamous pairs should split up more frequently after a breeding failure. Yet, deviations from the expected pattern "success-stay, failure-leave" have been reported in several species. One possible explanation for these deviations would be that individuals do not use only their own breeding performance (i.e., private information) but also that of others (i.e., public information) to decide whether or not to divorce. To test this hypothesis, we investigated the relative importance of private and public information for mate choice decisions in female zebra finches (Taeniopygia guttata).We manipulated the reproductive performance of breeding pairs and measured females' preferences for their mate and the neighbouring male first following pair formation and then seven weeks later when all females had laid eggs and the young were independent. Although all females reduced their preference for their mate after a breeding failure, the decrease was significant only when the neighbouring pair had reproduced successfully. Furthermore, there was no evidence that females biased the sex ratio of their offspring according to their mate's attractiveness. On the other hand, after reproduction, both successful and unsuccessful females increased their preferences for males who had produced a larger proportion of sons. Despite the fact that other mechanisms may have also contributed to our findings, we suggest that females changed their mate preferences based on the proportion of sons produced by successful males, because offspring sex ratio reflects the male's testosterone level at the moment of fertilization and hence is an indicator of his immune condition. PMID:22216351

  17. Male foraging efficiency, but not male problem-solving performance, influences female mating preferences in zebra finches.

    PubMed

    Chantal, Véronique; Gibelli, Julie; Dubois, Frédérique

    2016-01-01

    Experimental evidence suggests that females would prefer males with better cognitive abilities as mates. However, little is known about the traits reflecting enhanced cognitive skills on which females might base their mate-choice decisions. In particular, it has been suggested that male foraging performance could be used as an indicator of cognitive capacity, but convincing evidence for this hypothesis is still lacking. In the present study, we investigated whether female zebra finches (Taeniopygia guttata) modify their mating preferences after having observed the performance of males on a problem-solving task. Specifically, we measured the females' preferences between two males once before and once after an observation period, during which their initially preferred male was incapable of solving the task contrary to their initially less-preferred male. We also conducted a control treatment to test whether the shift in female preferences was attributable to differences between the two stimulus males in their foraging efficiency. Finally, we assessed each bird's performance in a color associative task to check whether females can discriminate among males based on their learning speed. We found that females significantly increased their preference toward the most efficient male in both treatments. Yet, there was no difference between the two treatments and we found no evidence that females assess male cognitive ability indirectly via morphological traits. Thus, our results suggest that females would not use the males' problem-solving performance as an indicator of general cognitive ability to gain indirect fitness benefits (i.e., good genes) but rather to assess their foraging efficiency and gain direct benefits. PMID:27635358

  18. The vocal repertoire of the domesticated zebra finch: a data-driven approach to decipher the information-bearing acoustic features of communication signals.

    PubMed

    Elie, Julie E; Theunissen, Frédéric E

    2016-03-01

    Although a universal code for the acoustic features of animal vocal communication calls may not exist, the thorough analysis of the distinctive acoustical features of vocalization categories is important not only to decipher the acoustical code for a specific species but also to understand the evolution of communication signals and the mechanisms used to produce and understand them. Here, we recorded more than 8000 examples of almost all the vocalizations of the domesticated zebra finch, Taeniopygia guttata: vocalizations produced to establish contact, to form and maintain pair bonds, to sound an alarm, to communicate distress or to advertise hunger or aggressive intents. We characterized each vocalization type using complete representations that avoided any a priori assumptions on the acoustic code, as well as classical bioacoustics measures that could provide more intuitive interpretations. We then used these acoustical features to rigorously determine the potential information-bearing acoustical features for each vocalization type using both a novel regularized classifier and an unsupervised clustering algorithm. Vocalization categories are discriminated by the shape of their frequency spectrum and by their pitch saliency (noisy to tonal vocalizations) but not particularly by their fundamental frequency. Notably, the spectral shape of zebra finch vocalizations contains peaks or formants that vary systematically across categories and that would be generated by active control of both the vocal organ (source) and the upper vocal tract (filter). PMID:26581377

  19. Learning to cope with degraded sounds: female zebra finches can improve their expertise in discriminating between male voices at long distances

    PubMed Central

    Mouterde, Solveig C.; Elie, Julie E.; Theunissen, Frédéric E.; Mathevon, Nicolas

    2014-01-01

    Reliable transmission of acoustic information about individual identity is of critical importance for pair bond maintenance in numerous monogamous songbirds. However, information transfer can be impaired by environmental constraints such as external noise or propagation-induced degradation. Birds have been shown to use several adaptive strategies to deal with difficult signal transmission contexts. Specifically, a number of studies have suggested that vocal plasticity at the emitter's level allows birds to counteract the deleterious effects of sound degradation. Although the communication process involves both the emitter and the receiver, perceptual plasticity at the receiver's level has received little attention. Here, we explored the reliability of individual recognition by female zebra finches (Taeniopygia guttata), testing whether perceptual training can improve discrimination of degraded individual vocal signatures. We found that female zebra finches are proficient in discriminating between calls of individual males at long distances, and even more so when they can train themselves with increasingly degraded signals over time. In this latter context, females succeed in discriminating between males as far as 250 m. This result emphasizes that adaptation to adverse communication conditions may involve not only the emitter's vocal plasticity but also the receptor's decoding process through on-going learning. PMID:24948627

  20. Two-photon deep imaging through skin and skull of Zebra finches: preliminary studies for in-vivo brain metabolism monitoring

    NASA Astrophysics Data System (ADS)

    Abi-Haidar, D.; Olivier, T.; Mottin, S.; Vignal, C.; Mathevon, N.

    2007-02-01

    Zebra Finches are songbirds which constitute a model for neuro-ethologists to study the neuro-mechanisms of vocal recognition. For this purpose, in vivo and non invasive monitoring of brain activity is required during acoustical stimulation. MRI (Magnetic Resonance Imaging) or NIRS (Near InfraRed Spectroscopy) are suitable methods for these measurements, even though MRI is difficult to link quantitatively with neural activity and NIRS suffers from a poor resolution. In the particular case of songbirds (whose skin is thin and quite transparent and whose skull structure is hollow), two-photon microscopy enables a quite deep penetration in tissues and could be an alternative. We present here preliminary studies on the feasability of two-photon microscopy in these conditions. To do so, we chose to image hollow fibers, filled with Rhodamine B, through the skin of Zebra finches in order to evaluate the spatial resolution we may expect in future in vivo experiments. Moreover, we used the reflectance-mode confocal configuration to evaluate the exponential decrease of backreflected light in skin and in skull samples. Following this procedure recently proposed by S.L. Jacques and co-workers, we planned to determine the scattering coefficient μ s and the anisotropy g of these tissues and make a comparison between fixed and fresh skin and skull samples for future Monte Carlo simulations of the scattering in our particular multi-layered structure.

  1. Novel Song-Stimulated Dendritic Spine Formation and Arc/Arg 3.1 Expression in Zebra Finch Auditory Telencephalon are Disrupted by Cannabinoid Agonism

    PubMed Central

    Gilbert, Marcoita T; Soderstrom, Ken

    2013-01-01

    Cannabinoids are well-established to alter processes of sensory perception; however neurophysiological mechanisms responsible remain unclear. Arc, an immediate-early gene (IEG) product involved in dendritic spine dynamics and necessary for plasticity changes such as long-term potentiation, is rapidly induced within zebra finch caudal medial nidopallium (NCM) following novel song exposure, a response that habituates after repeated stimuli. Arc appears unique in its rapid postsynaptic dendritic expression following excitatory input. Previously, we found that vocal development-altering cannabinoid treatments are associated with elevated dendritic spine densities in motor- (HVC) and learning-related (Area X) song regions of zebra finch telencephalon. Given Arc’s dendritic morphological role, we hypothesized that cannabinoid-altered spine densities may involve Arc-related signaling. To test this, we examined the ability of the cannabinoid agonist WIN55212-2 (WIN) to: (1) acutely disrupt song-induced Arc expression; (2) interfere with habituation to auditory stimuli and; (3) alter dendritic spine densities in auditory regions. We found that WIN (3 mg/kg) acutely reduced Arc expression within both NCM and Field L2 in an antagonist-reversible manner. WIN did not alter Arc expression in thalamic auditory relay Nucleus Ovoidalis (Ov), suggesting cannabinoid signaling selectively alters responses to auditory stimulation. Novel song stimulation rapidly increased dendritic spine densities within auditory telencephalon, an effect blocked by WIN pretreatments. Taken together, cannabinoid inhibition of both Arc induction and its habituation to repeated stimuli, combined with prevention of rapid increases in dendritic spine densities, implicates cannabinoid signaling in modulation of physiological processes important to auditory responsiveness and memory. PMID:24134952

  2. Developmental pattern of diacylglycerol lipase-α (DAGLα) immunoreactivity in brain regions important for song learning and control in the zebra finch (Taeniopygia guttata)

    PubMed Central

    Soderstrom, Ken; Wilson, Ashley R.

    2013-01-01

    Zebra finch song is a learned behavior dependent upon successful progress through a sensitive period of late-postnatal development. This learning is associated with maturation of distinct brain nuclei and the fiber tract interconnections between them. We have previously found remarkably distinct and dense CB1 cannabinoid receptor expression within many of these song control brain regions, implying a normal role for endocannabinoid signaling in vocal learning. Activation of CB1 receptors via daily treatments with exogenous agonist during sensorimotor stages of song learning (but not in adulthood) results in persistent alteration of song patterns. Now we are working to understand physiological changes responsible for this cannabinoid-altered vocal learning. We have found that song-altering developmental treatments are associated with changes in expression of endocannabinoid signaling elements, including CB1 receptors and the principal CNS endogenous agonist, 2-AG. Within CNS, 2-AG is produced largely through activity of the α isoform of the enzyme diacylglycerol lipase (DAGLα). To better appreciate the role of 2-AG production in normal vocal development we have determined the spatial distribution of DAGLα expression within zebra finch CNS during vocal development. Early during vocal development at 25 days, DAGLα staining is typically light and of fibroid processes. Staining peaks late in the sensorimotor stage of song learning at 75 days and is characterized by fiber, neuropil and some staining of both small and large cell somata. Results provide insight to the normal role for endocannabinoid signaling in the maturation of brain regions responsible for song learning and vocal-motor output, and suggest mechanisms by which exogenous cannabinoid exposure alters acquisition of this form of vocal communication. PMID:24140814

  3. Circulating breeding and pre-breeding prolactin and LH are not associated with clutch size in the zebra finch (Taeniopygia guttata).

    PubMed

    Ryan, Calen P; Dawson, Alistair; Sharp, Peter J; Meddle, Simone L; Williams, Tony D

    2014-06-01

    Clutch size is a fundamental predictor of avian fitness, widely-studied from evolutionary and ecological perspectives, but surprisingly little is known about the physiological mechanisms regulating clutch size variation. The only formal mechanistic hypothesis for avian clutch-size determination predicts an anti-gonadal effect of circulating prolactin (PRL) via the inhibition of luteinizing hormone (LH), and has become widely-accepted despite little experimental support. Here we investigated the relationship between pre-breeding and breeding plasma PRL and LH and clutch-size in captive-breeding female zebra finches (Taeniopygia guttata). Using a repeated-measures design, we followed individual females from pre-breeding, through multiple breeding attempts, and attempted to decrease PRL using the D2-receptor agonist, bromocriptine. Clutch size was independent of variation in pre-breeding PRL or LH, although pre-breeding LH was negatively correlated with the time between pairing and the onset of laying. Clutch size was independent of variation in plasma PRL on all days of egg-laying. Bromocriptine treatment had no effect on plasma PRL, but in this breeding attempt clutch size was also independent of plasma PRL. Finally, we found no evidence for an inverse relationship between plasma PRL and LH levels, as predicted if PRL had inhibitory effects via LH. Thus, our data fail to provide any support for the involvement of circulating PRL in clutch size determination. These findings suggest that alternative models for hormonal control of avian clutch size need to be considered, perhaps involving downstream regulation of plasma PRL at the level of the ovary, or other hormones that have not been considered to date.

  4. Genomic Landscape of Long Terminal Repeat Retrotransposons (LTR-RTs) and Solo LTRs as Shaped by Ectopic Recombination in Chicken and Zebra Finch.

    PubMed

    Ji, Yanzhu; DeWoody, J Andrew

    2016-06-01

    Transposable elements (TEs) are nearly ubiquitous among eukaryotic genomes, but TE contents vary dramatically among phylogenetic lineages. Several mechanisms have been proposed as drivers of TE dynamics in genomes, including the fixation/loss of a particular TE insertion by selection or drift as well as structural changes in the genome due to mutation (e.g., recombination). In particular, recombination can have a significant and directional effect on the genomic TE landscape. For example, ectopic recombination removes internal regions of long terminal repeat retrotransposons (LTR-RTs) as well as one long terminal repeat (LTR), resulting in a solo LTR. In this study, we focus on the intra-species dynamics of LTR-RTs and solo LTRs in bird genomes. The distribution of LTR-RTs and solo LTRs in birds is intriguing because avian recombination rates vary widely within a given genome. We used published linkage maps and whole genome assemblies to study the relationship between recombination rates and LTR-removal events in the chicken and zebra finch. We hypothesized that regions with low recombination rates would harbor more full-length LTR-RTs (and fewer solo LTRs) than regions with high recombination rates. We tested this hypothesis by comparing the ratio of full-length LTR-RTs and solo LTRs across chromosomes, across non-overlapping megabase windows, and across physical features (i.e., centromeres and telomeres). The chicken data statistically supported the hypothesis that recombination rates are inversely correlated with the ratio of full-length to solo LTRs at both the chromosome level and in 1-Mb non-overlapping windows. We also found that the ratio of full-length to solo LTRs near chicken telomeres was significantly lower than those ratios near centromeres. Our results suggest a potential role of ectopic recombination in shaping the chicken LTR-RT genomic landscape.

  5. Cocaine- and amphetamine-regulated transcript peptide (CART) in the brain of zebra finch, Taeniopygia guttata: Organization, interaction with neuropeptide Y, and response to changes in energy status.

    PubMed

    Singh, Omprakash; Kumar, Santosh; Singh, Uday; Kumar, Vinod; Lechan, Ronald M; Singru, Praful S

    2016-10-15

    Cocaine- and amphetamine-regulated transcript (CART) has emerged as a potent anorectic agent. CART is widely distributed in the brain of mammals, amphibians, and teleosts, but the relevant information in avian brain is not available. In birds, CART inhibits food intake, whereas neuropeptide Y (NPY), a well-known orexigenic peptide, stimulates it. How these neuropeptides interact in the brain to regulate energy balance is not known. We studied the distribution of CART-immunoreactivity in the brain of zebra finch, Taeniopygia guttata, its interaction with NPY, and their response to dynamic energy states. CART-immunoreactive fibers were found in the subpallium, hypothalamus, midbrain, and brainstem. Conspicuous CART-immunoreactive cells were observed in the bed nucleus of the stria terminalis, hypothalamic paraventricular, supraoptic, dorsomedial, infundibular (IN), lateral hypothalamic, Edinger-Westphal, and parabrachial nuclei. Hypothalamic sections of fed, fasted, and refed animals were immunostained with cFos, NPY, and CART antisera. Fasting dramatically increased cFos- and NPY-immunoreactivity in the IN, followed by rapid reduction by 2 hours and restoration to normal fed levels 6-10 hours after refeeding. CART-immunoreactive fibers in IN showed a significant reduction during fasting and upregulation with refeeding. Within the IN, double immunofluorescence revealed that 94 ± 2.1% of NPY-immunoreactive neurons were contacted by CART-immunoreactive fibers and 96 ± 2.8% NPY-immunoreactive neurons expressed cFos during fasting. Compared to controls, superfused hypothalamic slices of fasted birds treated with CART-peptide showed a significant reduction (P < 0.001) in NPY-immunoreactivity in the IN. As in other vertebrates, CART in the brain of T. guttata may perform several functions, and has a particularly important role in the hypothalamic regulation of energy homeostasis. J. Comp. Neurol. 524:3014-3041, 2016. © 2016 Wiley Periodicals, Inc. PMID:27018984

  6. Enriched Expression and Developmental Regulation of the Middle-Weight Neurofilament (NF-M) Gene in Song Control Nuclei of the Zebra Finch

    PubMed Central

    VELHO, TARCISO A.F.; LOVELL, PETER; MELLO, CLAUDIO V.

    2014-01-01

    Songbirds evolved a complex set of dimorphic telencephalic nuclei that are essential for the learning and production of song. These nuclei, which together make up the oscine song control system, present several neurochemical properties that distinguish them from the rest of the telencephalon. Here we show that the expression of the gene encoding the middle-weight neurofilament (NF-M), an important component of the neuronal cytoskeleton and a useful tool for studying the cytarchitectonic organization of mammalian cortical areas, is highly enriched in large neurons within pallial song control nuclei (nucleus HVC, robustus nucleus of the arcopallium, and lateral magnocellular nucleus of the nidopallium) of male zebra finches (Taeniopygia guttata). We also show that this transcript is highly expressed in large neurons in the medulla, pons, midbrain, and thalamus. Moreover, we demonstrate that NF-M expression in song control nuclei changes during postembryonic development, peaking during an early phase of the song-learning period that coincides with the maturation of the song system. We did not observe changes in NF-M expression in auditory areas or in song control nuclei in the contexts of hearing song or singing, although these contexts result in marked induction of the transcription factor ZENK. This observation suggests that NF-M might not be under the regulatory control of ZENK in auditory areas or in song control nuclei. Overall, our data indicate that NF-M is a neurochemical marker for pallial song control nuclei and provide suggestive evidence of an involvement of NF-M in the development and/or maturation of the oscine song control system. PMID:17120287

  7. Plasma reactive oxygen metabolites and non-enzymatic antioxidant capacity are not affected by an acute increase of metabolic rate in zebra finches.

    PubMed

    Beamonte-Barrientos, Rene; Verhulst, Simon

    2013-07-01

    Understanding the sources of variation in oxidative stress level is a challenging issue due to the implications of oxidative stress for late age diseases, longevity and life-history trade-offs. Reactive oxygen species that cause oxidative stress are mostly a by-product of energy metabolism and it is therefore often assumed that oxidative stress is proportional to energy consumption. In mammals, an increased metabolic rate induced by cold exposure generally increases oxidative stress. However, compared to mammals, birds generate fewer free radicals per ATP produced and hence it is not obvious that, in birds, a cold-induced increase of metabolic rate increase oxidative stress. We tested whether cold-induced increase in metabolic rate increased oxidative stress in zebra finches by exposing individuals to cold and warm overnight temperatures. We registered metabolic rate and plasma levels of non-enzymatic antioxidants and reactive oxygen metabolites (ROMs), a measure of oxidative damage. Metabolic rate was on average 88 % higher in cold compared to warm temperature, with females being stronger affected than males. However, temperature had no effect on plasma antioxidants or our measure of oxidative damage. Middle-age birds had higher levels of plasma antioxidants than younger and older birds, but age was unrelated to ROMs. Birds showed repeatability of plasma ROMs across temperatures but not of non-enzymatic antioxidants. In contrast to similar studies in mammals, our results do not show evidence of increased oxidative stress in plasma after an acute cold-induced increase of metabolic rate but research in more bird species is needed to assess the generality of this pattern.

  8. Use of a barbed tool by an adult and a juvenile woodpecker finch (Cactospiza pallida).

    PubMed

    Sabine, Tebbich; Irmgard, Teschke; Erica, Cartmill; Sophia, Stankewitz

    2012-02-01

    Here we describe the modification and use of a new tool type in the woodpecker finch (Cactospiza pallida). This species is known to habitually use twigs or cactus spines to extract arthropods out of tree holes. We observed an adult and a juvenile bird using several barbed twigs from introduced blackberry bushes (Rubus niveus) which the adult bird had first modified by removing leaves and side twigs. The barbs of blackberry tools provide a novel functional feature not present in tools made from native plants and de-leafing of twigs never has been observed before. Both birds were observed using several of these tools to extract prey from under the bark of the native scalesia tree (Scalesia penduculta). They oriented the twigs such that the barbs pointed towards themselves; this rendered the barbs functional as they could be used to drag prey out of a crevice. The juvenile bird first watched the adult using the tool and then used the tool that the adult bird had left under the bark at the same location and in the same way as the adult. Our observation highlights the fact that opportunities for the transmission of social information do occur in the wild and indicates that woodpecker finches are flexible in their choice of tool material and tool modification.

  9. The effects of natural biofilms on the reattachment of young adult zebra mussels to artificial substrata.

    PubMed

    Kavouras, Jerry H; Maki, James S

    2003-08-01

    This laboratory study examined the effects of natural biofilms on the reattachment of young adult zebra mussels, Dreissena polymorpha, in Petri dishes. Natural biofilms were developed in glass and polystyrene Petri dishes using water samples collected at various times of the year. Biofilms were developed over 1, 3, 8, and 14 d. Controls were clean glass and polystyrene Petri dishes. Zebra mussels collected from the field (< or = 10 mm, ventral length) were placed in the dishes and their reattachment by byssal threads was recorded after 1 d. Zebra mussels reattached to the dish surface or the shells of other mussels in the dish, or remained unattached. The data indicate that reattachment to clean glass was greater than to clean polystyrene (p < or = 0.05, ANOVA), but there were no consistent differences between reattachment to filmed polystyrene and filmed glass dish surfaces. Zebra mussels in control and filmed glass dishes reattached in higher percentages to the dish surface compared to the shells of other mussels (p < or = 0.05, ANOVA). There was no difference in mussel of reattachment between the dish surface and the shells of other mussels in most control polystyrene dishes (p > 0.05, ANOVA), whereas in filmed polystyrene the percentage of reattachment to the dish surface was greater than to the shells of other mussels (p < or = 0.05, ANOVA). These results indicate that substratum wettability and the presence of biofilms on some types of substrata can be factors in the reattachment of young adult zebra mussels.

  10. Auditory scene analysis in estrildid finches (Taeniopygia guttata and Lonchura striata domestica): a species advantage for detection of conspecific song.

    PubMed

    Benney, K S; Braaten, R F

    2000-06-01

    Operant-conditioning techniques were used to investigate the ability of zebra finches (Taeniopygia guttata) and Bengalese finches (Lonchura striata domestica) to detect a zebra finch or a Bengalese finch target song intermixed with other birdsongs. Sixteen birds were trained to respond to the presence of a particular target song, either of their own species (n = 8) or of another species (n = 8). The birds were able to learn a discrimination between song mixtures that contained a target song and song mixtures that did not, and they were able to maintain their response to the target song when it was mixed with novel songs. Zebra finches, but not Bengalese finches, learned the discrimination with a conspecific target more quickly and were worse at detecting a Bengalese finch in the presence of a conspecific song. The results indicate that selective attention to birdsongs within an auditory scene is related to their biological relevance.

  11. Auditory scene analysis in estrildid finches (Taeniopygia guttata and Lonchura striata domestica): a species advantage for detection of conspecific song.

    PubMed

    Benney, K S; Braaten, R F

    2000-06-01

    Operant-conditioning techniques were used to investigate the ability of zebra finches (Taeniopygia guttata) and Bengalese finches (Lonchura striata domestica) to detect a zebra finch or a Bengalese finch target song intermixed with other birdsongs. Sixteen birds were trained to respond to the presence of a particular target song, either of their own species (n = 8) or of another species (n = 8). The birds were able to learn a discrimination between song mixtures that contained a target song and song mixtures that did not, and they were able to maintain their response to the target song when it was mixed with novel songs. Zebra finches, but not Bengalese finches, learned the discrimination with a conspecific target more quickly and were worse at detecting a Bengalese finch in the presence of a conspecific song. The results indicate that selective attention to birdsongs within an auditory scene is related to their biological relevance. PMID:10890589

  12. Young and intense: FoxP2 immunoreactivity in Area X varies with age, song stereotypy, and singing in male zebra finches.

    PubMed

    Thompson, Christopher K; Schwabe, Fabian; Schoof, Alexander; Mendoza, Ezequiel; Gampe, Jutta; Rochefort, Christelle; Scharff, Constance

    2013-01-01

    FOXP2 is a transcription factor functionally relevant for learned vocalizations in humans and songbirds. In songbirds, FoxP2 mRNA expression in the medium spiny neurons of the basal ganglia song nucleus Area X is developmentally regulated and varies with singing conditions in different social contexts. How individual neurons in Area X change FoxP2 expression across development and in social contexts is not known, however. Here we address this critical gap in our understanding of FoxP2 as a link between neuronal networks and behavior. We used a statistically unbiased analysis of FoxP2-immunoreactivity (FoxP2-IR) on a neuron-by-neuron basis and found a bimodal distribution of FoxP2-IR neurons in Area X: weakly-stained and intensely-stained. The density of intensely-stained FoxP2-IR neurons was 10 times higher in juveniles than in adults, exponentially decreased with age, and was negatively correlated with adult song stability. Three-week old neurons labeled with BrdU were more than five times as likely to be intensely-stained than weakly-stained. The density of FoxP2-IR putative migratory neurons with fusiform-shaped nuclei substantially decreased as birds aged. The density of intensely-stained FoxP2-IR neurons was not affected by singing whereas the density of weakly-stained FoxP2-IR neurons was. Together, these data indicate that young Area X medium spiny neurons express FoxP2 at high levels and decrease expression as they become integrated into existing neural circuits. Once integrated, levels of FoxP2 expression correlate with singing behavior. Together, these findings raise the possibility that FoxP2 levels may orchestrate song learning and song stereotypy in adults by a common mechanism.

  13. Behavioral relevance of species-specific vasotocin anatomy in gregarious finches

    PubMed Central

    Kelly, Aubrey M.; Goodson, James L.

    2013-01-01

    Despite substantial species differences in the vasotocin/vasopressin (VT/VP) circuitry of the medial bed nucleus of the stria terminalis (BSTm) and lateral septum (LS; a primary projection target of BSTm VT/VP cells), functional consequences of this variation are poorly known. Previous experiments in the highly gregarious zebra finch (Estrildidae: Taeniopygia guttata) demonstrate that BSTm VT neurons promote gregariousness in a male-specific manner and reduce anxiety in both sexes. However, in contrast to the zebra finch, the less gregarious Angolan blue waxbill (Estrildidae: Uraeginthus angolensis) exhibits fewer VT-immunoreactive cells in the BSTm as well as differences in receptor distribution across the LS subnuclei, suggesting that knockdown of VT production in the BSTm would produce behavioral effects in Angolan blue waxbills that are distinct from zebra finches. Thus, we here quantified social contact, gregariousness (i.e., preference for the larger of two groups), and anxiety-like behavior following bilateral antisense knockdown of VT production in the BSTm of male and female Angolan blue waxbills. We find that BSTm VT neurons promote social contact, but not gregariousness (as in male zebra finches), and that antisense effects on social contact are significantly stronger in male waxbills than in females. Knockdown of BSTm VT production has no effect on anxiety-like behavior. These data provide novel evidence that species differences in the VT/VP circuitry arising in the BSTm are accompanied by species-specific effects on affiliation behaviors. PMID:24381536

  14. Management of zebras and zebra hybrids (zebroids).

    PubMed

    Wiedner, Ellen B; Lindsay, William A; Isaza, Ramiro

    2012-01-01

    Equine practitioners are sometimes asked to treat zebras or zebra-horse or zebra-donkey hybrids. Although these equids are subject to many of the same health issues as domestic horses, they cannot be handled like horses and generally require heavy sedation to full anesthesia, even for minor procedures. This usually necessitates the use of ultrapotent narcotics administered by remote delivery systems. This article discusses the handling, sedation, anesthesia, and common medical issues of zebras and zebra hybrids.

  15. Characterization of the finch embryo supports evolutionary conservation of the naive stage of development in amniotes.

    PubMed

    Mak, Siu-Shan; Alev, Cantas; Nagai, Hiroki; Wrabel, Anna; Matsuoka, Yoko; Honda, Akira; Sheng, Guojun; Ladher, Raj K

    2015-09-11

    Innate pluripotency of mouse embryos transits from naive to primed state as the inner cell mass differentiates into epiblast. In vitro, their counterparts are embryonic (ESCs) and epiblast stem cells (EpiSCs), respectively. Activation of the FGF signaling cascade results in mouse ESCs differentiating into mEpiSCs, indicative of its requirement in the shift between these states. However, only mouse ESCs correspond to the naive state; ESCs from other mammals and from chick show primed state characteristics. Thus, the significance of the naive state is unclear. In this study, we use zebra finch as a model for comparative ESC studies. The finch blastoderm has mESC-like properties, while chick blastoderm exhibits EpiSC features. In the absence of FGF signaling, finch cells retained expression of pluripotent markers, which were lost in cells from chick or aged finch epiblasts. Our data suggest that the naive state of pluripotency is evolutionarily conserved among amniotes.

  16. Zebra mussel life history

    SciTech Connect

    Ackerman, J.D.

    1995-06-01

    The success of introduced zebra mussels (Dreissena polymorpha (Pallas) and Dreissena bugensis Andrusova) can be related in large parttot a life history that is unlike that of the indigenous freshwater fauna and yet is conserved with marine bivalves. Following external fertilization and embryological development, there is a brief trochophore stage. With the development of a velum and the secretion of a D-shaped larval shell, the larva becomes a D-shaped veliger, which is the first recognizable planktonic larva. Later, the secretion of a second larval shell leads to the last obligate free-swimming veliger stage known as the veliconcha. The last larval stage known as the pediveliger, however, can both swim using its velum or crawl using its fully-functional foot. Pediveligers actively select substrates on which they {open_quotes}settle{close_quotes} by secreting byssal threads and undergo metamorphosis to become plantigrade mussels. The secretion of the adult shell and concomitant changes in growth axis leads to the heteromyariant or mussel-like shape, which is convergent with marine mussels. Like a number of other bivalves, zebra mussels produce byssal threads as adults, but these attachments may be broken enabling their translocation to new areas. The recognition and examination of these life history traits will lead to a better understanding of zebra mussel biology.

  17. Abcb and Abcc transporter homologs are expressed and active in larvae and adults of zebra mussel and induced by chemical stress.

    PubMed

    Navarro, Anna; Weißbach, Susann; Faria, Melissa; Barata, Carlos; Piña, Benjamin; Luckenbach, Till

    2012-10-15

    Multixenobiotic resistance (MXR) of aquatic invertebrates has so far been associated with cellular efflux activity mediated by P-glycoprotein (ABCB1) and MRP (multidrug resistance protein; ABCC) type ABC (ATP binding cassette) transporters. Expression and activity of an abcb1/Abcb1 homolog has been shown in eggs and larvae of the zebra mussel Dreissena polymorpha. Here we report identification of a partial cDNA sequence of an abcc/Abcc homolog from zebra mussel that is transcribed and active as a cellular efflux transporter in embryos and gill tissue of adult mussels. Transcript expression levels were comparatively low in eggs and sharply increased after fertilization, then maintaining high expression levels in 1 and 2 dpf (days post fertilization) larvae. MK571, a known inhibitor of mammalian ABCC transporters, blocks efflux of calcein-am in larvae and gill tissue as indicated by elevated calcein fluorescence; this indicates the presence of active Abcc protein in cells of the larvae and gills. Dacthal and mercury used as chemical stressors both induced expression of abcb1 and abcc mRNAs in larvae; accordingly, assays with calcein-am and ABCB1 inhibitor reversin 205 and ABCC inhibitor MK571 indicated enhanced Abcb1 and Abcc efflux activities. Responses to chemicals were different in gills, where abcb1 transcript abundances were enhanced in dacthal and mercury treatments, whereas abcc mRNA was only increased with mercury. Abcb1 and Abcc activities did not in all cases show increases that were according to respective mRNA levels; thus, Abcc activity was significantly higher with dacthal, whereas Abcb1 activity was unchanged with mercury. Our data indicate that abcb1/Abcb1 and abcc/Abcc transporters are expressed and active in larvae and adult stages of zebra mussel. Expression of both genes is induced as cellular stress response, but regulation appears to differ in larvae and tissue of adult stages. PMID:22819804

  18. Zebra batteries

    NASA Astrophysics Data System (ADS)

    Sudworth, J. L.

    By using molten sodium chloroaluminate as secondary electrolyte, a series of solid transition metal chlorides can be used as positive electrodes in cells with sodium as the negative and beta-alumina as the solid electrlyte. Nickel chloride is preferred and Zebra batteries based on this cell reaction have been developed to the pilot-line production stage. The batteries have a number of features which make them attractive for electric-vehicle applications. Thus, the cells can be assebled in the discharged state eliminating the need to handle liquid sodium. By locating the positive electrode inside the beta-alumina tube, square cell cases can be used giving maximum packing efficiency in batteries. The absence of corrosion in the cell leads to a long life and high reliability. For electric-vehicle applications safety is very imporant, and crash testing has shown that even serious damage to the battery in a crash situation would not present a significant additional hazard to the driver or passengers. The remaining technical challenges are to increase the specific power of the battery towards the end of discharge and to demonstrate that the processes, which have been developed for cell and battery production, are capable of meeting the cost targets.

  19. Intra-ejaculate sperm selection in female zebra finches.

    PubMed

    Hemmings, N; Bennison, C; Birkhead, T R

    2016-06-01

    Among internal fertilizers, typically fewer than 1% sperm survive the journey through the oviduct. Several studies suggest that the sperm reaching the ovum-the 'fertilizing set'-comprise a non-random sub-population, but the characteristics of this group remain unclear. We tested whether oviductal selection in birds results in a morphologically distinct subset of sperm, by exploiting the fact that the fertilizing set are trapped by the perivitelline layer of the ovum. We show that these sperm have remarkably low morphological variation, as well as smaller head size and greater tail length, compared with those inseminated. Our study shows that the morphological composition of sperm-rather than length alone-influences success in reaching the ovum. PMID:27277953

  20. Intra-ejaculate sperm selection in female zebra finches

    PubMed Central

    Bennison, C.; Birkhead, T. R.

    2016-01-01

    Among internal fertilizers, typically fewer than 1% sperm survive the journey through the oviduct. Several studies suggest that the sperm reaching the ovum—the ‘fertilizing set’—comprise a non-random sub-population, but the characteristics of this group remain unclear. We tested whether oviductal selection in birds results in a morphologically distinct subset of sperm, by exploiting the fact that the fertilizing set are trapped by the perivitelline layer of the ovum. We show that these sperm have remarkably low morphological variation, as well as smaller head size and greater tail length, compared with those inseminated. Our study shows that the morphological composition of sperm—rather than length alone—influences success in reaching the ovum. PMID:27277953

  1. Long-Distance Retinoid Signaling in the Zebra Finch Brain

    PubMed Central

    Roeske, Tina C.; Scharff, Constance; Olson, Christopher R.; Nshdejan, Arpik; Mello, Claudio V.

    2014-01-01

    All-trans retinoic acid (ATRA), the main active metabolite of vitamin A, is a powerful signaling molecule that regulates large-scale morphogenetic processes during vertebrate embryonic development, but is also involved post-natally in regulating neural plasticity and cognition. In songbirds, it plays an important role in the maturation of learned song. The distribution of the ATRA-synthesizing enzyme, zRalDH, and of ATRA receptors (RARs) have been described, but information on the distribution of other components of the retinoid signaling pathway is still lacking. To address this gap, we have determined the expression patterns of two obligatory RAR co-receptors, the retinoid X receptors (RXR) α and γ, and of the three ATRA-degrading cytochromes CYP26A1, CYP26B1, and CYP26C1. We have also studied the distribution of zRalDH protein using immunohistochemistry, and generated a refined map of ATRA localization, using a modified reporter cell assay to examine entire brain sections. Our results show that (1) ATRA is more broadly distributed in the brain than previously predicted by the spatially restricted distribution of zRalDH transcripts. This could be due to long-range transport of zRalDH enzyme between different nuclei of the song system: Experimental lesions of putative zRalDH peptide source regions diminish ATRA-induced transcription in target regions. (2) Four telencephalic song nuclei express different and specific subsets of retinoid-related receptors and could be targets of retinoid regulation; in the case of the lateral magnocellular nucleus of the anterior nidopallium (lMAN), receptor expression is dynamically regulated in a circadian and age-dependent manner. (3) High-order auditory areas exhibit a complex distribution of transcripts representing ATRA synthesizing and degrading enzymes and could also be a target of retinoid signaling. Together, our survey across multiple connected song nuclei and auditory brain regions underscores the prominent role of retinoid signaling in modulating the circuitry that underlies the acquisition and production of learned vocalizations. PMID:25393898

  2. Characterization of the finch embryo supports evolutionary conservation of the naive stage of development in amniotes

    PubMed Central

    Mak, Siu-Shan; Alev, Cantas; Nagai, Hiroki; Wrabel, Anna; Matsuoka, Yoko; Honda, Akira; Sheng, Guojun; Ladher, Raj K

    2015-01-01

    Innate pluripotency of mouse embryos transits from naive to primed state as the inner cell mass differentiates into epiblast. In vitro, their counterparts are embryonic (ESCs) and epiblast stem cells (EpiSCs), respectively. Activation of the FGF signaling cascade results in mouse ESCs differentiating into mEpiSCs, indicative of its requirement in the shift between these states. However, only mouse ESCs correspond to the naive state; ESCs from other mammals and from chick show primed state characteristics. Thus, the significance of the naive state is unclear. In this study, we use zebra finch as a model for comparative ESC studies. The finch blastoderm has mESC-like properties, while chick blastoderm exhibits EpiSC features. In the absence of FGF signaling, finch cells retained expression of pluripotent markers, which were lost in cells from chick or aged finch epiblasts. Our data suggest that the naive state of pluripotency is evolutionarily conserved among amniotes. DOI: http://dx.doi.org/10.7554/eLife.07178.001 PMID:26359635

  3. Are Horses Like Zebras, or Vice Versa? Children's Sensitivity to the Asymmetries of Directional Comparisons

    ERIC Educational Resources Information Center

    Chestnut, Eleanor K.; Markman, Ellen M.

    2016-01-01

    Adults exhibit strong preferences when framing symmetrical relations. Adults prefer, for example, "A zebra is like a horse" to "A horse is like a zebra," and "The bicycle is near the building" to "The building is near the bicycle." This is because directional syntax requires more typical or prominent items…

  4. Darwin’s finches treat their feathers with a natural repellent

    PubMed Central

    Cimadom, Arno; Causton, Charlotte; Cha, Dong H.; Damiens, David; Fessl, Birgit; Hood-Nowotny, Rebecca; Lincango, Piedad; Mieles, Alejandro E.; Nemeth, Erwin; Semler, Elizabeth M.; Teale, Stephen A.; Tebbich, Sabine

    2016-01-01

    Darwin’s finches are highly innovative. Recently we recorded for the first time a behavioural innovation in Darwin’s finches outside the foraging context: individuals of four species rubbed leaves of the endemic tree Psidium galapageium on their feathers. We hypothesised that this behaviour serves to repel ectoparasites and tested the repellency of P. galapageium leaf extracts against parasites that negatively affect the fitness of Darwin’s finches, namely mosquitoes and the invasive hematophagous fly Philornis downsi. Mosquitoes transmit pathogens which have recently been introduced by humans and the larvae of the fly suck blood from nestlings and incubating females. Our experimental evidence demonstrates that P. galapageium leaf extracts repel both mosquitoes and adult P. downsi and also inhibit the growth of P. downsi larvae. It is therefore possible that finches use this plant to repel ectopoarasites. PMID:27721475

  5. Mate choice in adult female Bengalese finches: females express consistent preferences for individual males and prefer female-directed song performances.

    PubMed

    Dunning, Jeffery L; Pant, Santosh; Bass, Aaron; Coburn, Zachary; Prather, Jonathan F

    2014-01-01

    In the process of mate selection by female songbirds, male suitors advertise their quality through reproductive displays in which song plays an important role. Females evaluate the quality of each signal and the associated male, and the results of that evaluation guide expression of selective courtship displays. Some studies reveal broad agreement among females in their preferences for specific signal characteristics, indicating that those features are especially salient in female mate choice. Other studies reveal that females differ in their preference for specific characteristics, indicating that in those cases female evaluation of signal quality is influenced by factors other than simply the physical properties of the signal. Thus, both the physical properties of male signals and specific traits of female signal evaluation can impact female mate choice. Here, we characterized the mate preferences of female Bengalese finches. We found that calls and copulation solicitation displays are equally reliable indicators of female preference. In response to songs from an array of males, each female expressed an individual-specific song preference, and those preferences were consistent across tests spanning many months. Across a population of females, songs of some males were more commonly preferred than others, and females preferred female-directed songs more than undirected songs, suggesting that some song features are broadly attractive. Preferences were indistinguishable for females that did or did not have social experience with the singers, indicating that female preference is strongly directed by song features rather than experiences associated with the singer. Analysis of song properties revealed several candidate parameters that may influence female evaluation. In an initial investigation of those parameters, females could be very selective for one song feature yet not selective for another. Therefore, multiple song parameters are evaluated independently

  6. Mate choice in adult female Bengalese finches: females express consistent preferences for individual males and prefer female-directed song performances.

    PubMed

    Dunning, Jeffery L; Pant, Santosh; Bass, Aaron; Coburn, Zachary; Prather, Jonathan F

    2014-01-01

    In the process of mate selection by female songbirds, male suitors advertise their quality through reproductive displays in which song plays an important role. Females evaluate the quality of each signal and the associated male, and the results of that evaluation guide expression of selective courtship displays. Some studies reveal broad agreement among females in their preferences for specific signal characteristics, indicating that those features are especially salient in female mate choice. Other studies reveal that females differ in their preference for specific characteristics, indicating that in those cases female evaluation of signal quality is influenced by factors other than simply the physical properties of the signal. Thus, both the physical properties of male signals and specific traits of female signal evaluation can impact female mate choice. Here, we characterized the mate preferences of female Bengalese finches. We found that calls and copulation solicitation displays are equally reliable indicators of female preference. In response to songs from an array of males, each female expressed an individual-specific song preference, and those preferences were consistent across tests spanning many months. Across a population of females, songs of some males were more commonly preferred than others, and females preferred female-directed songs more than undirected songs, suggesting that some song features are broadly attractive. Preferences were indistinguishable for females that did or did not have social experience with the singers, indicating that female preference is strongly directed by song features rather than experiences associated with the singer. Analysis of song properties revealed several candidate parameters that may influence female evaluation. In an initial investigation of those parameters, females could be very selective for one song feature yet not selective for another. Therefore, multiple song parameters are evaluated independently

  7. Treatment of equine sarcoid in seven Cape mountain zebra (Equus zebra zebra).

    PubMed

    Marais, Hendrik J; Page, Patrick C

    2011-10-01

    Equine sarcoid has been diagnosed in endangered Cape mountain zebra (Equus zebra zebra) in at least two game reserves in South Africa, with prevalence as high as 53% in Bontebok National Park. Seven Cape mountain zebras with sarcoids were treated with either surgical excision, 5-fluorouracil, allogenous vaccine, or a combination of 5-fluorouracil and allogenous vaccine. One of the two sarcoids on one of the 5-fluorouracil-treated zebras was left untreated. The microscopic features of the tumors evaluated showed either all or most of the typical epidermal and dermal histologic features of equine sarcoid. The zebras were examined 2 yr posttreatment to determine outcome. All sarcoids had resolved except on the zebra on which one of the sarcoids was left untreated. The efficacy of the three treatment methods in Cape mountain zebra is encouraging.

  8. Do woodpecker finches acquire tool-use by social learning?

    PubMed Central

    Tebbich, S.; Taborsky, M.; Fessl, B.; Blomqvist, D.

    2001-01-01

    Tool-use is widespread among animals, but except in primates the development of this behaviour is poorly known. Here, we report on the first experimental study to our knowledge of the mechanisms underlying the acquisition of tool-use in a bird species. The woodpecker finch Cactospiza pallida, endemic to the Galápagos Islands, is a famous textbook example of tool-use in animals. This species uses modified twigs or cactus spines to pry arthropods out of tree holes. Using nestlings and adult birds from the field, we tested experimentally whether woodpecker finches learn tool-use socially. We show that social learning is not essential for the development of tool-use: all juveniles developed tool-use regardless of whether or not they had a tool-using model. However, we found that not all adult woodpecker finches used tools in our experiments. These non-tool-using individuals also did not learn this task by observing tool-using conspecifics. Our results suggest that tool-use behaviour depends on a very specific learning disposition that involves trial-and-error learning during a sensitive phase early in ontogeny. PMID:11674865

  9. Zebra mussel mitigation; overview

    SciTech Connect

    Claudi, R.

    1995-06-01

    Zebra mussels cause a number of problems to industrial raw water users as well as having serious impact on civil structures exposed to mussel infested waters. The largest volume of water (up to 90% of the total) drawn into most industrial and power generating plants, is for cooling and heat transfer. The rest of the volume is used for other plant processes, such as make-up in steam systems, and service systems used for cleaning, air conditions, fire protection and human consumption. All raw water systems are vulnerable to zebra mussel infestation to greater or lesser degree. To-date, many different chemical and non-chemical techniques for zebra mussel control have been investigated. However, the treatment of choice for most facilities is based on chemical control. This has been the common practice in Europe and so far it has been the case in North America. This is likely to change as the environmental constraints on release of chemicals into natural water bodies continue to increase. This paper deals with the different steps raw water users should take when deciding on a mitigation strategy, the mitigation measures available to-date and those that have been proposed for the control of zebra mussels in industrial systems.

  10. Zebra mussel monitoring

    SciTech Connect

    Hennagir, T.

    1994-01-01

    In less than a decade, zebra mussels have become the latest environmental scourge to plague the North American power industry. Infestations in the Great Lakes region have already reached natural disaster proportions. The invasion shows little sign of subsiding; Michigan's inland waters are the next most likely threatened area. In the southern United States, the mussles' migration has extended about 50 miles deeper than experts had originally predicted. By the year 2000, zebra mussel monitoring and control efforts will cost business and industry $5 billion, according to the federal Aquatic Nuisance Prevention and Control Act of 1990. Estimates of more than $1 million to control mussel fouling are projected for the Great Lakes area alone. While small independent hydropower stations are not as susceptible to zebra mussles as coal or nuclear facilities, there is cause for concern. Infestations can quickly foul hydropower plant components, hampering equipment operation and reducing facility efficiency. In extreme cases, leaving the mussels unchecked can result in stoplog gate flow blockage or false water level gauge readings. Advance prevention is often an effective first-line of defense against this troublesome, rapidly spreading and extremely prolific mollusk. Mussel monitoring efforts should begin a year in advance of when zebra mussels are expected to appear in a given location. Hydropower facility components that come into contact or rely exclusively on raw water are at greatest risk, as are other external components such as embayment walls, screens, trashracks and fish ladders.

  11. Predation on exotic zebra mussels by native fishes: Effects on predator and prey

    USGS Publications Warehouse

    Magoulick, D.D.; Lewis, L.C.

    2002-01-01

    1. Exotic zebra mussels, Dreissena polymorpha, occur in southern U.S. waterways in high densities, but little is known about the interaction between native fish predators and zebra mussels. Previous studies have suggested that exotic zebra mussels are low profitability prey items and native vertebrate predators are unlikely to reduce zebra mussel densities. We tested these hypotheses by observing prey use of fishes, determining energy content of primary prey species of fishes, and conducting predator exclusion experiments in Lake Dardanelle, Arkansas. 2. Zebra mussels were the primary prey eaten by 52.9% of blue catfish, Ictalurus furcatus; 48.2% of freshwater drum, Aplodinotus grunniens; and 100% of adult redear sunfish, Lepomis microlophus. Blue catfish showed distinct seasonal prey shifts, feeding on zebra mussels in summer and shad, Dorosoma spp., during winter. Energy content (joules g-1) of blue catfish prey (threadfin shad, Dorosoma petenense; gizzard shad, D. cepedianum; zebra mussels; and asiatic clams, Corbicula fluminea) showed a significant species by season interaction, but shad were always significantly greater in energy content than bivalves examined as either ash-free dry mass or whole organism dry mass. Fish predators significantly reduced densities of large zebra mussels (>5 mm length) colonising clay tiles in the summers of 1997 and 1998, but predation effects on small zebra mussels (???5 mm length) were less clear. 3. Freshwater drum and redear sunfish process bivalve prey by crushing shells and obtain low amounts of higher-energy food (only the flesh), whereas blue catfish lack a shell-crushing apparatus and ingest large amounts of low-energy food per unit time (bivalves with their shells). Blue catfish appeared to select the abundant zebra mussel over the more energetically rich shad during summer, then shifted to shad during winter when shad experienced temperature-dependent stress and mortality. Native fish predators can suppress adult zebra

  12. A house finch (Haemorhous mexicanus) spleen transcriptome reveals intra- and interspecific patterns of gene expression, alternative splicing and genetic diversity in passerines

    PubMed Central

    2014-01-01

    Background With its plumage color dimorphism and unique history in North America, including a recent population expansion and an epizootic of Mycoplasma gallisepticum (MG), the house finch (Haemorhous mexicanus) is a model species for studying sexual selection, plumage coloration and host-parasite interactions. As part of our ongoing efforts to make available genomic resources for this species, here we report a transcriptome assembly derived from genes expressed in spleen. Results We characterize transcriptomes from two populations with different histories of demography and disease exposure: a recently founded population in the eastern US that has been exposed to MG for over a decade and a native population from the western range that has never been exposed to MG. We utilize this resource to quantify conservation in gene expression in passerine birds over approximately 50 MY by comparing splenic expression profiles for 9,646 house finch transcripts and those from zebra finch and find that less than half of all genes expressed in spleen in either species are expressed in both species. Comparative gene annotations from several vertebrate species suggest that the house finch transcriptomes contain ~15 genes not yet found in previously sequenced vertebrate genomes. The house finch transcriptomes harbour ~85,000 SNPs, ~20,000 of which are non-synonymous. Although not yet validated by biological or technical replication, we identify a set of genes exhibiting differences between populations in gene expression (n = 182; 2% of all transcripts), allele frequencies (76 FST ouliers) and alternative splicing as well as genes with several fixed non-synonymous substitutions; this set includes genes with functions related to double-strand break repair and immune response. Conclusions The two house finch spleen transcriptome profiles will add to the increasing data on genome and transcriptome sequence information from natural populations. Differences in splenic expression between

  13. Prevention of zebra mussel infestation and dispersal during aquaculture operations

    USGS Publications Warehouse

    Waller, D.L.; Fisher, S.W.; Dabrowska, H.

    1996-01-01

    The zebra mussel Dreissena polymorpha, an exotic invasive species, poses a major threat to North American fish management programs and the aquaculture industry. Fish hatcheries may become infected with zebra mussels from a variety of sources, including the water supply, fish shipments, boats, and equipment. The hatcheries could then serve as agents for the overland dispersal of zebra mussels into stocked waters and to other fish hatcheries. We evaluated the effectiveness and safety of aquaculture chemicals for use in controlling zebra mussels in fish hatcheries and preventing dispersal of veligers during fish transport. Chemicals were evaluated for use in fish transport and as disinfectants for ponds and equipment. Standardized static toxicity tests were conducted with representative species of warmwater, coolwater, and coldwater fishes and with larval (3-d-old veligers), early juvenile (settling larvae), and adult zebra mussels. Chemical concentrations and exposure durations were based on recommended treatment levels for fish, eggs, and ponds. Recommended treatment levels were also exceeded, if necessary, to establish lethal levels for zebra mussels of different developmental stages. Our results indicate that some chemicals currently in use in hatcheries may be effective for controlling zebra mussels in various operations. Chloride salts were the safest and most effective therapeutants tested for use in fish transport. The toxicity of chloride salts to fish varied among species and with temperature; only one treatment regime (sodium chloride at 10,000 mg/L) was safe to all fish species that we tested, but it was only effective on veliger and settler stages of the zebra mussel. Effective disinfectants were benzalkonium chloride for use on equipment and rotenone for use in ponds after fish are harvested. The regulatory status of the identified chemicals is discussed as well as several nonchemical control alternatives.

  14. Sisyphean evolution in Darwin's finches.

    PubMed

    McKay, Bailey D; Zink, Robert M

    2015-08-01

    The trajectory of speciation involves geographic isolation of ancestral populations followed by divergence by natural selection, genetic drift or sexual selection. Once started, the process may experience fits and starts, as sometimes diverging populations intermittently reconnect. In theory populations might cycle between stages of differentiation and never attain species status, a process we refer to as Sisyphean evolution. We argue that the six putative ground finch species (genus Geospiza) of the Galápagos Islands represent a dramatic example of Sisyphean evolution that has been confused with the standard model of speciation. The dynamic environment of the Galápagos, closely spaced islands, and frequent dispersal and introgression have prevented the completion of the speciation process. We suggest that morphological clusters represent locally adapted ecomorphs, which might mimic, and have been confused with, species, but these ecomorphs do not form separate gene pools and are ephemeral in space and time. Thus the pattern of morphological, behavioural and genetic variation supports recognition of a single species of Geospiza, which we suggest should be recognized as Darwin's ground finch (Geospiza magnirostris). We argue that instead of providing an icon of insular speciation and adaptive radiation, which is featured in nearly every textbook on evolutionary biology, Darwin's ground finch represents a potentially more interesting phenomenon, one of transient morphs trapped in an unpredictable cycle of Sisyphean evolution. Instead of revealing details of the origin of species, the mechanisms underlying the transient occurrence of ecomorphs provide one of the best illustrations of the antagonistic effects of natural selection and introgression.

  15. Experimental test of the effect of introduced hematophagous flies on corticosterone levels of breeding Darwin's finches.

    PubMed

    Knutie, Sarah A; Koop, Jennifer A H; French, Susannah S; Clayton, Dale H

    2013-11-01

    Parasites can negatively affect the evolutionary fitness of their hosts by eliciting physiological stress responses. Parasite-induced stress can be monitored by measuring changes in the adrenal steroid hormone corticosterone. We examined the effect of an invasive parasite on the corticosterone concentrations of a common species of Darwin's finch, the medium ground finch (Geospiza fortis). Philornis downsi (Diptera: Muscidae) is a parasitic nest fly recently introduced to the Galapagos Islands, where it feeds on the blood of nestlings and breeding adult female finches. Previous work shows that P. downsi significantly reduces the reproductive success of several species of finches. We predicted that the effect of P. downsi on host reproductive success is mediated by stress responses in breeding female finches. High stress levels could reduce the ability of females to invest in offspring, thus decreasing their reproductive success. To test this hypothesis, we experimentally manipulated the abundance of P. downsi in nests, then measured baseline and acute stress-induced corticosterone levels, body condition, and hematocrit (red blood cell content). Acute stress-induced corticosterone levels increased over baseline levels, but this response did not differ significantly with parasite treatment. There was also no significant difference in the body condition or hematocrit of females from parasitized versus non-parasitized nests. Our results suggest that the lower reproductive success of females from parasitized nests is not mediated by a physiological stress response.

  16. A comparison of spontaneous problem-solving abilities in three estrildid finch (Taeniopygia guttata, Lonchura striata var. domestica, Stagonopleura guttata) species.

    PubMed

    Schmelz, Martin; Krüger, Oliver; Call, Josep; Krause, E Tobias

    2015-11-01

    Cognition has been extensively studied in primates while other, more distantly related taxa have been neglected for a long time. More recently, there has been an increased interest in avian cognition, with the focus mostly on big-brained species like parrots and corvids. However, the majority of bird species has never systematically been studied in diverse cognitive tasks other than memory and learning tasks, so not much can yet be concluded about the relevant factors for the evolution of cognition. Here we examined 3 species of the estrildid finch family in problem-solving tasks. These granivorous, non-tool-using birds are distributed across 3 continents and are not known for high levels of innovation or spontaneous problem solving in the wild. In this study, our aim was to find such abilities in these species, assess what role domestication might play with a comparison of 4 genetically separated zebra finch strains, and to look for between-species differences between zebra finches, Bengalese finches, and diamond firetails. Furthermore, we established a 3-step spontaneous problem-solving procedure with increasing levels of complexity. Results showed that some estrildid finches were generally capable of spontaneously solving problems of variable complexity to obtain food. We found striking differences in these abilities between species, but not between strains within species, and offer a discussion of potential reasons. Our established methodology can now be applied to a larger number of bird species for phylogenetic comparisons on the behavioral level to get a deeper understanding of the evolution of cognitive abilities.

  17. The use of positive reinforcement in training zebra sharks (Stegostoma fasciatum).

    PubMed

    Marranzino, Ashley

    2013-01-01

    Positive reinforcement training (PRT) was used on 4 adult zebra sharks, Stegostoma fasciatum, housed at the Downtown Aquarium, Denver, to determine the ability of zebra sharks to become desensitized to various stimuli associated with veterinary procedures. One male and 3 female sharks were trained for 12 weeks. As a result of PRT, all 4 zebra sharks were desensitized to staying within a closed holding tank off of the main exhibit, the presence of multiple trainers in the closed holding tank, and tactile stimulation. One of the 4 zebra sharks was also successfully desensitized to the presence of a stretcher being brought into the holding tank. All of these procedures are common in veterinary examinations, and it is hoped that desensitization to these stimuli will reduce the stress associated with examinations. The training accomplished has allowed for easier maintenance of the zebra sharks by the aquarium staff and an improvement in the care of the sharks.

  18. Preference of redear sunfish on zebra mussels and rams-horn snails

    USGS Publications Warehouse

    French, John R. P.; Morgan, Michael N.

    1995-01-01

    We tested prey preferences of adult (200- to 222-mm long) redear sunfish (Lepomis microlophus) on two size classes of zebra mussels (Dreissena polymorpha) and two-ridge rams-horns (Helisoma anceps) in experimental aquaria. We also tested physical limitations on consuming these mollusks and determined prey bioenergetic profitability. Redear sunfish strongly preferred rams-horns over zebra mussels, but they displayed no size preference for either prey. Ingestion was not physically limited since both prey species up to 15-mm long fit within the pharyngeal gapes of redear sunfish. Rams-horns were more bioenergetically profitable than zebra mussels and ingestion of rams-horn shell fragments was about three times less than zebra mussels. Rams-horns were somewhat more resistant to shell-crushing, but all size ranges of both prey species tested were crushable by redear sunfish. These studies suggested that the redear sunfish should not be considered a panacea for biological control of zebra mussels.

  19. A Zebra in the Classroom.

    ERIC Educational Resources Information Center

    Leake, Devin; Morvillo, Nancy

    1998-01-01

    Describes the care and breeding of zebra fish, suggests various experiments and observations easily performed in a classroom setting, and provides some ideas to further student interest and exploration of these organisms. (DDR)

  20. Darwin's Galapagos finches in modern biology.

    PubMed

    Abzhanov, Arhat

    2010-04-12

    One of the classic examples of adaptive radiation under natural selection is the evolution of 15 closely related species of Darwin's finches (Passeriformes), whose primary diversity lies in the size and shape of their beaks. Since Charles Darwin and other members of the Beagle expedition collected these birds on the Galápagos Islands in 1835 and introduced them to science, they have been the subjects of intense research. Many biology textbooks use Darwin's finches to illustrate a variety of topics of evolutionary theory, such as speciation, natural selection and niche partitioning. Today, as this Theme Issue illustrates, Darwin's finches continue to be a very valuable source of biological discovery. Certain advantages of studying this group allow further breakthroughs in our understanding of changes in recent island biodiversity, mechanisms of speciation and hybridization, evolution of cognitive behaviours, principles of beak/jaw biomechanics as well as the underlying developmental genetic mechanisms in generating morphological diversity. Our objective was to bring together some of the key workers in the field of ecology and evolutionary biology who study Darwin's finches or whose studies were inspired by research on Darwin's finches. Insights provided by papers collected in this Theme Issue will be of interest to a wide audience.

  1. An aggression-specific cell type in the anterior hypothalamus of finches

    PubMed Central

    Goodson, James L.; Kelly, Aubrey M.; Kingsbury, Marcy A.; Thompson, Richmond R.

    2012-01-01

    The anterior hypothalamus (AH) is a major integrator of neural processes related to aggression and defense, but cell types in the AH that selectively promote aggression are unknown. We here show that aggression is promoted in a very selective and potent manner by dorsal AH neurons that produce vasoactive intestinal polypeptide (VIP). Fos activity in a territorial finch, the violet-eared waxbill (Estrildidae: Uraeginthus granatina) is positively related to aggression in the dorsal AH, overlapping a population of VIP-producing neurons. VIP is known to promote territorial aggression in songbirds, and thus we used antisense oligonucleotides to selectively block AH VIP production in male and female waxbills. This manipulation virtually abolishes aggression, reducing the median number of displacements in a 3-min resident–intruder test from 38 in control subjects to 0 in antisense subjects. Notably, most antisense and control waxbills exhibit an agonistic response such as a threat or agonistic call within 2 s of intrusion. Thus, antisense subjects clearly classify intruders as offensive, but fail to attack. Other social and anxiety-like behaviors are not affected and VIP cell numbers correlate positively with aggression, suggesting that these cells selectively titrate aggression. Additional experiments in the gregarious zebra finch (Estrildidae: Taeniopygia guttata) underscore this functional specificity. Colony-housed finches exhibit significant reductions in aggression (primarily nest defense) following AH VIP knockdown, but no effects are observed for social preferences, pair bonding, courtship, maintenance behaviors, or anxiety-like behaviors. To our knowledge, these findings represent a unique identification of an aggression-specific cell type in the brain. PMID:22872869

  2. Recent data on zebra patterns

    NASA Astrophysics Data System (ADS)

    Chernov, G. P.; Yan, Y. H.; Fu, Q. J.; Tan, Ch. M.

    2005-07-01

    A comparative analysis of two recent solar radio outbursts around 3 GHz with zebra structures and fiber bursts in their dynamical radio spectra is carried out using all available ground-based and satellite data (SOHO, TRACE, RHESSI). The latest theoretical models of the zebra pattern are critically discussed. New data on microwave zebra structures and fiber bursts suggests that they are analogous to similar structures observed at meter wavelengths. It was discovered that in the 2,6-3,8 GHz frequency band more than 34 zebra stripes can appear simultaneously, and some isolated fiber bursts can continuously be transformed into zebra stripes. This fact indicates a single origin for both structures. The zebra pattern was observed when the signs of magnetic reconnections were revealed in images of 195 Å UV lines, and radio sources coincided with positions of some new sources in hard X-rays. All the main properties of the stripes in emission and absorption can be explained if they are associated with interactions between electrostatic plasma waves and whistlers, taking into account the quasi-linear diffusion of fast particles with the loss-cone distribution on whistlers. In this model it is possible to obtain realistic values for the magnetic field strength of B ≈ 160~G at the plasma level of about 3 GHz. The double plasma resonance model for the zebra pattern based on the known realistic dependences of electron density and magnetic field yields a frequency dependence for the frequency separation between stripes that does not agree with the observations.

  3. Experimental test of the effect of introduced hematophagous flies on corticosterone levels of breeding Darwin’s finches

    PubMed Central

    Knutie, Sarah A.; Koop, Jennifer A.H.; French, Susannah S.; Clayton, Dale H.

    2015-01-01

    Parasites can negatively affect the evolutionary fitness of their hosts by eliciting physiological stress responses. Parasite-induced stress can be monitored by measuring changes in the adrenal steroid hormone corticosterone. We examined the effect of an invasive parasite on the corticosterone concentrations of a common species of Darwin’s finch, the medium ground finch (Geospiza fortis). Philornis downsi (Diptera: Muscidae) is a parasitic nest fly recently introduced to the Galapagos Islands, where it feeds on the blood of nestlings and breeding adult female finches. Previous work shows that P. downsi significantly reduces the reproductive success of several species of finches. We predicted that the effect of P. downsi on host reproductive success is mediated by stress responses in breeding female finches. High stress levels could reduce the ability of females to invest in offspring, thus decreasing their reproductive success. To test this hypothesis, we experimentally manipulated the abundance of P. downsi in nests, then measured baseline and acute stress-induced corticosterone levels, body condition, and hematocrit (red blood cell content). Acute stress-induced corticosterone levels increased over baseline levels, but this response did not differ significantly with parasite treatment. There was also no significant difference in the body condition or hematocrit of females from parasitized versus non-parasitized nests. Our results suggest that the lower reproductive success of females from parasitized nests is not mediated by a physiological stress response. PMID:23892015

  4. Optimizing efficiency of zebra mussel monitoring at TVA power plants

    SciTech Connect

    Kerley, B.L.

    1995-06-01

    The Tennessee Valley Authority (TVA) began monitoring for zebra mussels in spring 1992 and first detected veligers entering plant intake at Shawnee, Allen and Cumberland Fossil Plans in summer 1993. Existing information indicated that densities of zebra mussel veligers at plant intakes did not always correspond to densities in critical pipe units; however, a more accurate predictive technique was unavailable. The two sites chosen for this project were Shawnee Fossil Plant on the Ohio River and Allen Fossil Plant on the Mississippi River. The project involved a coordinated series of experiments to determine how densities of zebra mussel veligers varied throughout the day, how veliger densities estimated outside the plants related to estimates at different internal locations, and how growth rate of adult zebra mussels compared using measurements taken inside and outside the plants and from the two different rivers. The data indicated no significant difference in veliger densities from samples collected at the intakes and samples collected inside the plants. There was also no significant difference in densities between samples collected inside the plants. There was also no significant difference in densities between samples taken at different times of the day. The data did indicate a significant difference in density estimates between samples collected on different days and between densities in the rivers compared to densities being drawn into the plant. The results will be used to assist plant staff in evaluating future data and in planning a more effective and cost efficient monitoring program.

  5. Zebra mussel mortality with chlorine

    SciTech Connect

    Van Benschoten, J.E.; Jensen, J.N.; Harrington, D.; DeGirolamo, D.J.

    1995-05-01

    The rate of mortality of the zebra mussel in response to chlorine is described by a kinetic model that combines a statistical characterization of mussel mortality with a disinfection-type modeling approach. Parameter estimates were made with nine sets of data from experiments conducted in Niagara River water. From the kinetic model, an operational diagram was constructed that describes the time to 95% mortality as a function of chlorine concentration and temperature. Either the model or the diagram can be used to assist utilities in planning chlorination treatments for controlling zebra mussels.

  6. Ontogeny of the cranial skeleton in a Darwin's finch (Geospiza fortis)

    PubMed Central

    Genbrugge, Annelies; Heyde, Anne-Sophie; Adriaens, Dominique; Boone, Matthieu; Van Hoorebeke, Luc; Dirckx, Joris; Aerts, Peter; Podos, Jeffrey; Herrel, Anthony

    2011-01-01

    Darwin's finches are a model system in ecological and evolutionary research, but surprisingly little is known about their skull morphology and development. Indeed, only the early beak development and external variation in adult beak shape has been studied. Understanding the development of the skull from embryo up to the adult is important to gain insights into how selection acts upon, and drives, variation in beak shape. Here, we provide a detailed description of the skeletal development of the skull in the medium ground finch (Geospiza fortis). Although the ossification sequence of the cranial elements is broadly similar to that observed for other birds, some differences can be observed. Unexpectedly, our data show that large changes in skull shape take place between the nestling and the juvenile phases. The reorientation of the beak, the orbit and the formation of well-developed processes and cristae suggest that these changes are likely related to the use of the beak after leaving the nest. This suggests that the active use of the jaw muscles during seed cracking plays an important role in shaping the adult skull morphology and may be driving some of the intra-specific variation observed in species such as G. fortis. Investigating the development of the jaw muscles and their interaction with the observed ossification and formation of the skull and lower jaw would allow further insights into the ecology and evolution of beak morphology in Darwin's finches. PMID:21599660

  7. Science Learning Experience Involving Adults and Their Preadolescent and Adolescent Children.

    ERIC Educational Resources Information Center

    Gennaro, Eugene D.; And Others

    1980-01-01

    Describes a five-week course in animal behavior for parents and their middle-school-aged children offered at the Minnesota Zoological Garden. Course activities included discussions, film viewing, demonstrations, zoo observations, and home studies of gerbils or zebra finches. Results of the course are discussed. (CS)

  8. The use of chlorine dioxide for zebra mussel control - A perspective of treatment histories

    SciTech Connect

    Smolik, N.; Rusznak, L.; Anderson, J.; Hale, L.

    1995-06-01

    It is of utmost importance to provide updated performance results of various chemical treatments presently being utilized for zebra mussel control. Zebra mussels have a distinctive ability to endure environmental changes by reproducing effectively and attaching to various hard surfaces. These traits are cause for concern and have resulted in some operating difficulties for industries bordering infested waterways. Various methods are being employed by industries to deal with the problems associated with these species. One of the options is control via chemical treatment. Prior field test studies showed that chlorine dioxide was determined to be an effective molluscicidal agent for adult zebra mussel eradication. Continuous feed of chlorine dioxide at treatment levels ranging from 0.25 - 5.0 ppm above the oxidant demand provided 100% adult zebra mussel mortality which required between 2.9 - 8.8 days of treatment. Previous studies also showed that water temperature was an essential parameter in determining the time required to achieve 100% mortality of adult zebra mussels. Further field applications were undertaken at three electric utility sites located in the midwest. These facilities were concerned with the potential for zebra mussels to reduce efficiency and availability by blocking water flow or plugging equipment. Treatment applications at these facilities consisted of a continuous feed of chlorine dioxide ranging from 0.15 - 0.5 ppm above the oxidant demand. Significant mortality was achieved in monitored mussels tested at each utility in a period ranging from two to four days. This time period was directly related to a number of parameters, with the predominant one being water temperature. Data from these field applications is presented in this paper and confirms that chlorine dioxide is an effective molluscicide for adult zebra mussel control.

  9. Invasion of the zebra mussels

    SciTech Connect

    Giacomo, R.S.; Randell, N.G.

    1993-05-01

    This article describes the threat to efficiency and cost control that zebra mussels are to power plants and the raw-water intakes and pumping facilities for industrial and municipal water users. The topics of the article include control measures such as chlorination, use of potassium permanganate, and other options such as thermal backwashing and physical cleaning of intake piping.

  10. Fresnel incoherent correlation holography (FINCH): a review of research

    NASA Astrophysics Data System (ADS)

    Rosen, Joseph; Brooker, Gary

    2012-07-01

    In this review, we describe our method for creating holograms of incoherent objects, dubbed Fresnel incoherent correlation holography (FINCH). FINCH creates holograms by a single-channel on-axis incoherent interferometer process. Like any Fresnel hologram, the object is correlated with quadratic phase functions, but the correlation is carried out without any movement. Generally, in the FINCH system, light is reflected, or emitted, from a three-dimensional (3D) object, propagates through a spatial light modulator (SLM), and is recorded by a digital camera. The SLM is used as a beam-splitter of the single-channel incoherent interferometer, such that each spherical beam originated from each object point is split into two spherical beams with two different curve radiuses. Incoherent summing of the entire interferences between all the couples of the spherical beams creates the Fresnel hologram of the observed 3D object. When this hologram is reconstructed in the computer, the 3D properties of the object are revealed. In this review, we describe various aspects of FINCH which have been described recently, including FINCH of reflected white light, FINCH of fluorescence objects, a FINCH-based holographic fluorescence microscope, a FINCH configuration which capitalizes on the polarization sensitivity of the SLM and finally FINCH is analyzed in view of linear system theory.

  11. Epigenetics and the evolution of Darwin's Finches.

    PubMed

    Skinner, Michael K; Gurerrero-Bosagna, Carlos; Haque, M Muksitul; Nilsson, Eric E; Koop, Jennifer A H; Knutie, Sarah A; Clayton, Dale H

    2014-07-24

    The prevailing theory for the molecular basis of evolution involves genetic mutations that ultimately generate the heritable phenotypic variation on which natural selection acts. However, epigenetic transgenerational inheritance of phenotypic variation may also play an important role in evolutionary change. A growing number of studies have demonstrated the presence of epigenetic inheritance in a variety of different organisms that can persist for hundreds of generations. The possibility that epigenetic changes can accumulate over longer periods of evolutionary time has seldom been tested empirically. This study was designed to compare epigenetic changes among several closely related species of Darwin's finches, a well-known example of adaptive radiation. Erythrocyte DNA was obtained from five species of sympatric Darwin's finches that vary in phylogenetic relatedness. Genome-wide alterations in genetic mutations using copy number variation (CNV) were compared with epigenetic alterations associated with differential DNA methylation regions (epimutations). Epimutations were more common than genetic CNV mutations among the five species; furthermore, the number of epimutations increased monotonically with phylogenetic distance. Interestingly, the number of genetic CNV mutations did not consistently increase with phylogenetic distance. The number, chromosomal locations, regional clustering, and lack of overlap of epimutations and genetic mutations suggest that epigenetic changes are distinct and that they correlate with the evolutionary history of Darwin's finches. The potential functional significance of the epimutations was explored by comparing their locations on the genome to the location of evolutionarily important genes and cellular pathways in birds. Specific epimutations were associated with genes related to the bone morphogenic protein, toll receptor, and melanogenesis signaling pathways. Species-specific epimutations were significantly overrepresented in these

  12. Population genetic diversity and hybrid detection in captive zebras

    PubMed Central

    Ito, Hideyuki; Langenhorst, Tanya; Ogden, Rob; Inoue-Murayama, Miho

    2015-01-01

    Zebras are members of the horse family. There are three species of zebras: the plains zebra Equus quagga, the Grevy’s zebra E. grevyi and the mountain zebra E. zebra. The Grevy’s zebra and the mountain zebra are endangered, and hybridization between the Grevy’s zebra and the plains zebra has been documented, leading to a requirement for conservation genetic management within and between the species. We characterized 28 microsatellite markers in Grevy’s zebra and assessed cross-amplification in plains zebra and two of its subspecies, as well as mountain zebra. A range of standard indices were employed to examine population genetic diversity and hybrid populations between Grevy’s and plains zebra were simulated to investigate subspecies and hybrid detection. Microsatellite marker polymorphism was conserved across species with sufficient variation to enable individual identification in all populations. Comparative diversity estimates indicated greater genetic variation in plains zebra and its subspecies than Grevy’s zebra, despite potential ascertainment bias. Species and subspecies differentiation were clearly demonstrated and F1 and F2 hybrids were correctly identified. These findings provide insights into captive population genetic diversity in zebras and support the use of these markers for identifying hybrids, including the known hybrid issue in the endangered Grevy’s zebra. PMID:26294133

  13. Population genetic diversity and hybrid detection in captive zebras.

    PubMed

    Ito, Hideyuki; Langenhorst, Tanya; Ogden, Rob; Inoue-Murayama, Miho

    2015-08-21

    Zebras are members of the horse family. There are three species of zebras: the plains zebra Equus quagga, the Grevy's zebra E. grevyi and the mountain zebra E. zebra. The Grevy's zebra and the mountain zebra are endangered, and hybridization between the Grevy's zebra and the plains zebra has been documented, leading to a requirement for conservation genetic management within and between the species. We characterized 28 microsatellite markers in Grevy's zebra and assessed cross-amplification in plains zebra and two of its subspecies, as well as mountain zebra. A range of standard indices were employed to examine population genetic diversity and hybrid populations between Grevy's and plains zebra were simulated to investigate subspecies and hybrid detection. Microsatellite marker polymorphism was conserved across species with sufficient variation to enable individual identification in all populations. Comparative diversity estimates indicated greater genetic variation in plains zebra and its subspecies than Grevy's zebra, despite potential ascertainment bias. Species and subspecies differentiation were clearly demonstrated and F1 and F2 hybrids were correctly identified. These findings provide insights into captive population genetic diversity in zebras and support the use of these markers for identifying hybrids, including the known hybrid issue in the endangered Grevy's zebra.

  14. Mortality of zebra mussel, Dreissena polymorpha, veligers during downstream transport

    USGS Publications Warehouse

    Horvath, T.G.; Lamberti, G.A.

    1999-01-01

    1. Streams flowing from lakes which contain zebra mussels, Dreissena polymorpha, provide apparently suitable habitats for mussel colonization and downstream range expansion, yet most such streams contain few adult mussels. We postulated that mussel veligers experience high mortality during dispersal via downstream transport. They tested this hypothesis in Christiana Creek, a lake-outlet stream in south-western Michigan, U.S.A., in which adult mussel density declined exponentially with distance downstream. 2. A staining technique using neutral red was developed and tested to distinguish quickly live and dead veligers. Live and dead veligers were distinguishable after an exposure of fresh samples to 13.3 mg L-1 of neutral red for 3 h. 3. Neutral red was used to determine the proportion of live veligers in samples taken longitudinally along Christiana Creek. The proportion of live veligers (mean ?? SE) declined from 90 ?? 3% at the lake outlet to 40 ?? 8% 18 km downstream. 4. Veligers appear to be highly susceptible to damage by physical forces (e.g. shear), and therefore, mortality in turbulent streams could be an important mechanism limiting zebra mussel dispersal to downstream reaches. Predictions of zebra mussel spread and population growth should consider lake-stream linkages and high mortality in running waters.

  15. The function of zebra stripes.

    PubMed

    Caro, Tim; Izzo, Amanda; Reiner, Robert C; Walker, Hannah; Stankowich, Theodore

    2014-04-01

    Despite over a century of interest, the function of zebra stripes has never been examined systematically. Here we match variation in striping of equid species and subspecies to geographic range overlap of environmental variables in multifactor models controlling for phylogeny to simultaneously test the five major explanations for this infamous colouration. For subspecies, there are significant associations between our proxy for tabanid biting fly annoyance and most striping measures (facial and neck stripe number, flank and rump striping, leg stripe intensity and shadow striping), and between belly stripe number and tsetse fly distribution, several of which are replicated at the species level. Conversely, there is no consistent support for camouflage, predator avoidance, heat management or social interaction hypotheses. Susceptibility to ectoparasite attack is discussed in relation to short coat hair, disease transmission and blood loss. A solution to the riddle of zebra stripes, discussed by Wallace and Darwin, is at hand.

  16. Midbrain dopamine neurons reflect affiliation phenotypes in finches and are tightly coupled to courtship.

    PubMed

    Goodson, James L; Kabelik, David; Kelly, Aubrey M; Rinaldi, Jacob; Klatt, James D

    2009-05-26

    Mesolimbic dopamine (DA) circuits mediate a wide range of goal-oriented behavioral processes, and DA strongly influences appetitive and consummatory aspects of male sexual behavior. In both birds and mammals, mesolimbic projections arise primarily from the ventral tegmental area (VTA), with a smaller contribution from the midbrain central gray (CG). Despite the well known importance of the VTA cell group for incentive motivation functions, relationships of VTA subpopulations to specific aspects of social phenotype remain wholly undescribed. We now show that in male zebra finches (Estrildidae: Taeniopygia guttata), Fos activity within a subpopulation of tyrosine hydroxylase-immunoreactive (TH-ir; presumably dopaminergic) neurons in the caudal VTA is significantly correlated with courtship singing and coupled to gonadal state. In addition, the number of TH-ir neurons in this caudal subpopulation dichotomously differentiates courting from non-courting male phenotypes, and evolves in relation to sociality (flocking vs. territorial) across several related finch species. Combined, these findings for the VTA suggest that divergent social phenotypes may arise due to the differential assignment of "incentive value" to conspecific stimuli. TH-ir neurons of the CG (a population of unknown function in mammals) exhibit properties that are even more selectively and tightly coupled to the expression of courtship phenotypes (and appetitive courtship singing), both in terms of TH-ir cell number, which correlates significantly with constitutive levels of courtship motivation, and with TH-Fos colocalization, which increases in direct proportion to the phasic expression of song. We propose that these neurons may be core components of social communication circuits across diverse vertebrate taxa. PMID:19439662

  17. Detroit Edison conquers zebra mussels

    SciTech Connect

    Harwood, D.B.; Buda, D.J. )

    1993-11-01

    A potentially troublesome zebra mussel infestation at Detroit Edison's Harbor Beach Power Plant was nipped in time. Reducing the oxygen content of water inside the plant's water systems and using steam to thermally treat a colony of mussels that was established in the plant's screenhouse prevented the problem. So successful was the temperature treatment that it will be used regularly as part of the plant's annual mussel removal program.

  18. Electrocardiography of Grevy's zebras (Equus grevyi).

    PubMed

    Myers, Debbie A; Citino, Scott; Mitchell, Mark A

    2008-09-01

    Electrocardiograms (ECGs) are a good baseline test for assessing cardiac rhythm. ECGs have not been reported in any zebra species and in very few Perissodactyla species. Standard limb, six-lead ECGs were recorded in 23 anesthetized Grevy's zebras (Equus grevyi). Heart rate, RR interval, P-wave duration, RR maximum/minimum, PR interval, QRS duration, QT interval, ST segment deviation, P-wave amplitude, QRS amplitude, and T-wave amplitude were measured and calculated from lead II ECGs from these Grevy's zebras. Several variables were tested, including gender, age (0-24, 24-48, 48-180, and >180 mo), weight (<350 kg or >350 kg), pregnancy status, and anesthetic differences (standard dose or supplemented dose), to see if they affected ECG values in these animals. There were no significant differences in any of the ECG parameters between genders. RR and QT intervals were longer in older zebras; heart rates were faster in younger zebras. The RR and PR intervals, as well as the QRS duration, were greater in heavier zebras; heart rates were faster in lighter zebras. The RR interval was significantly longer in pregnant zebras. There were no significant differences in any of the ECG parameters for zebras anesthetized with a standardized dose of the drug combination etorphine-detomidine-acepromazine compared to those receiving additional supplements of these drugs and/or ketamine. All other parameters were not significantly different among groups, except where noted previously. The results of this research indicate that differences in ECG parameters in zebras may occur between animals of different ages, weights, and pregnancy status and that these factors should be considered when interpreting the respective ECGs of these zebras.

  19. New Concerns Emerge as Zebra Mussel Spreads.

    ERIC Educational Resources Information Center

    Walter, Martha L., Ed.

    1992-01-01

    Reports on the Zebra Mussel invasion of North American inland waterways. Discusses United States Army Corps of Engineers operations that may facilitate or be affected by the spread of Zebra Mussels, the threat to native clams, chemical and mechanical control methods, natural solutions, and ongoing research. (MCO)

  20. Androgen receptor gene polymorphism in zebra species.

    PubMed

    Ito, Hideyuki; Langenhorst, Tanya; Ogden, Rob; Inoue-Murayama, Miho

    2015-09-01

    Androgen receptor genes (AR) have been found to have associations with reproductive development, behavioral traits, and disorders in humans. However, the influence of similar genetic effects on the behavior of other animals is scarce. We examined the loci AR glutamine repeat (ARQ) in 44 Grevy's zebras, 23 plains zebras, and three mountain zebras, and compared them with those of domesticated horses. We observed polymorphism among zebra species and between zebra and horse. As androgens such as testosterone influence aggressiveness, AR polymorphism among equid species may be associated with differences in levels of aggression and tameness. Our findings indicate that it would be useful to conduct further studies focusing on the potential association between AR and personality traits, and to understand domestication of equid species. PMID:26236645

  1. Rope can help with early detection of zebra mussels

    SciTech Connect

    McNabb, C.

    1993-06-01

    Many of the waters in the western US meet all the ecological requirements of suitable habitat for zebra mussels, which can spread to new bodies of water by attaching to boats. With that in mind, Reclamation has launched Zebra Mussel Watch, a program aimed at early detection of the mussel in western waters. As part of the watch program, Reclamation suggests attaching one end of a rope to a weight such as a brock, rick, or cinder block, and placing the weight in shallow water to detect the arrival of zebra mussels. Any kind of rope will do, but nylon is preferred because small mussels are easier to distinguish on nylon's smooth surface than on ropes with rough surfaces. Young mussels smaller than the head of a common straight pin are transparent when they first settle and probably will not be visible to the naked eye for several weeks, when they are larger and they take on the appearance of small, dark-colored clams. [Note: over time, algae, bacteria, and debris will cause the rope to darken. So the color of the rope used doesn't make much difference.] Hang a rope in 8 feet or less of well-oxygenated water where wave action will not move the bottom of the rope to any great degree. (Zebra mussels like slow currents and will not attach where the current is moving 4 to 5 feet per second or faster.) Leave the rope in the water two or three weeks to allow microorganisms to grow on it. Young mussels will settle on surfaces that are coated with algae and other microscopic organisms. Then, at two- to three-week intervals, lift the rope and examine it for young mussels. If adults are around, the young eventually will show up. Reclamation believes that by detecting the first arrival of the mussels, it can implement plans to control the spread of the mussels and alert nearby projects to the approaching menace.

  2. Zebra Stripes through the Eyes of Their Predators, Zebras, and Humans.

    PubMed

    Melin, Amanda D; Kline, Donald W; Hiramatsu, Chihiro; Caro, Tim

    2016-01-01

    The century-old idea that stripes make zebras cryptic to large carnivores has never been examined systematically. We evaluated this hypothesis by passing digital images of zebras through species-specific spatial and colour filters to simulate their appearance for the visual systems of zebras' primary predators and zebras themselves. We also measured stripe widths and luminance contrast to estimate the maximum distances from which lions, spotted hyaenas, and zebras can resolve stripes. We found that beyond ca. 50 m (daylight) and 30 m (twilight) zebra stripes are difficult for the estimated visual systems of large carnivores to resolve, but not humans. On moonless nights, stripes are difficult for all species to resolve beyond ca. 9 m. In open treeless habitats where zebras spend most time, zebras are as clearly identified by the lion visual system as are similar-sized ungulates, suggesting that stripes cannot confer crypsis by disrupting the zebra's outline. Stripes confer a minor advantage over solid pelage in masking body shape in woodlands, but the effect is stronger for humans than for predators. Zebras appear to be less able than humans to resolve stripes although they are better than their chief predators. In conclusion, compared to the uniform pelage of other sympatric herbivores it appears highly unlikely that stripes are a form of anti-predator camouflage. PMID:26799935

  3. Zebra Stripes through the Eyes of Their Predators, Zebras, and Humans.

    PubMed

    Melin, Amanda D; Kline, Donald W; Hiramatsu, Chihiro; Caro, Tim

    2016-01-01

    The century-old idea that stripes make zebras cryptic to large carnivores has never been examined systematically. We evaluated this hypothesis by passing digital images of zebras through species-specific spatial and colour filters to simulate their appearance for the visual systems of zebras' primary predators and zebras themselves. We also measured stripe widths and luminance contrast to estimate the maximum distances from which lions, spotted hyaenas, and zebras can resolve stripes. We found that beyond ca. 50 m (daylight) and 30 m (twilight) zebra stripes are difficult for the estimated visual systems of large carnivores to resolve, but not humans. On moonless nights, stripes are difficult for all species to resolve beyond ca. 9 m. In open treeless habitats where zebras spend most time, zebras are as clearly identified by the lion visual system as are similar-sized ungulates, suggesting that stripes cannot confer crypsis by disrupting the zebra's outline. Stripes confer a minor advantage over solid pelage in masking body shape in woodlands, but the effect is stronger for humans than for predators. Zebras appear to be less able than humans to resolve stripes although they are better than their chief predators. In conclusion, compared to the uniform pelage of other sympatric herbivores it appears highly unlikely that stripes are a form of anti-predator camouflage.

  4. Arthropod parasites of springbok, gemsbok, kudus, giraffes and Burchell's and Hartmann's zebras in the Etosha and Hardap Nature Reserves, Namibia.

    PubMed

    Horak, I G; Anthonissen, M; Krecek, R C; Boomker, J

    1992-12-01

    A total of 48 springbok, 48 gemsbok, 23 kudus and 6 giraffes were examined for ticks and lice, while 9 Burchell's zebras and 6 Hartmann's mountain zebras were examined only for ticks. Springbok and gemsbok were shot in both the Etosha National Park in the north and the Hardap Nature Reserve in the south of Namibia. All the other animals were shot in the Etosha National Park. A total of 7 ixodid tick species and 8 lice species were recovered. The springbok carried few ticks. The adults of a Rhipicephalus sp. (near R. oculatus) were most numerous on the gemsbok, especially during November. The kudus were the only animals harbouring Rhipicephalus zambeziensis. Adult Hyalomma truncatum, followed by adult Hyalomma marginatum rufipes, were most abundant on the giraffes and adult Rhipicephalus evertsi mimeticus were commonest on the zebras.

  5. ZEBRA battery meets USABC goals

    NASA Astrophysics Data System (ADS)

    Dustmann, Cord-H.

    In 1990, the California Air Resources Board has established a mandate to introduce electric vehicles in order to improve air quality in Los Angeles and other capitals. The United States Advanced Battery Consortium has been formed by the big car companies, Electric Power Research Institute (EPRI) and the Department of Energy in order to establish the requirements on EV-batteries and to support battery development. The ZEBRA battery system is a candidate to power future electric vehicles. Not only because its energy density is three-fold that of lead acid batteries (50% more than NiMH) but also because of all the other EV requirements such as power density, no maintenance, summer and winter operation, safety, failure tolerance and low cost potential are fulfilled. The electrode material is plain salt and nickel in combination with a ceramic electrolyte. The cell voltage is 2.58 V and the capacity of a standard cell is 32 Ah. Some hundred cells are connected in series and parallel to form a battery with about 300 V OCV. The battery system including battery controller, main circuit-breaker and cooling system is engineered for vehicle integration and ready to be mounted in a vehicle [J. Gaub, A. van Zyl, Mercedes-Benz Electric Vehicles with ZEBRA Batteries, EVS-14, Orlando, FL, Dec. 1997]. The background of these features are described.

  6. Steam treatment of zebra mussels

    SciTech Connect

    Tsou, J.; Rybarik, D.L.; Thiel, J.; Mussalli, Y.G.; Collins, F.

    1996-08-01

    Steam injection into intake bays is a nonchemical method to control zebra mussels. This technique was demonstrated at Dairyland Power Cooperative`s J.P. Madgett Station located in Alma, Wisconsin. The project was funded by the EPRI Zebra Mussel Consortium which includes: Dairyland Power Cooperative, Central Illinois Public Service, Duke Power, Illinois Power Company, PSI Energy, Public Service Electric & Gas, and Tennessee Valley Authority. This technique can be used by other power plants around the nation. The steam treatments were performed at the J.P. Madgen intake in Alma, Wisconsin, on September 14 and 18, 1994. The J.P. Madgen Station has two water intake bays with capacities of approximately 295,000 gallons and 265,000 gallons each. Each intake can be isolated, permitting either full or reduced generation depending on river temperature conditions. In addition to the intake bays, the outside fire protection loop and hydrants were also treated with the hot water from one of the bays. This paper presents the process design, piping and steam educator configurations, portable industrial boiler sizing and description, and the thermocouples to monitor the water temperature in the intake bay. The biological mortality and control test protocol and treatment results are also presented. Treatment effectiveness was 100%, however equipment installation and operation was more problematic than anticipated. 3 refs., 5 figs., 2 tabs.

  7. How to save the rarest Darwin's finch from extinction: the mangrove finch on Isabela Island.

    PubMed

    Fessl, Birgit; Young, Glyn H; Young, Richard P; Rodríguez-Matamoros, Jorge; Dvorak, Michael; Tebbich, Sabine; Fa, John E

    2010-04-12

    Habitat destruction and predation by invasive alien species has led to the disappearance of several island populations of Darwin's finches but to date none of the 13 recognized species have gone extinct. However, driven by rapid economic growth in the Galápagos, the effects of introduced species have accelerated and severely threatened these iconic birds. The critically endangered mangrove finch (Camarhynchus heliobates) is now confined to three small mangroves on Isabela Island. During 2006-2009, we assessed its population status and monitored nesting success, both before and after rat poisoning. Population size was estimated at around only 100 birds for the two main breeding sites, with possibly 5-10 birds surviving at a third mangrove. Before rat control, 54 per cent of nests during incubation phase were predated with only 18 per cent of nests producing fledglings. Post-rat control, nest predation during the incubation phase fell to 30 per cent with 37 per cent of nests producing fledglings. During the nestling phase, infestation by larvae of the introduced parasitic fly (Philornis downsi) caused 14 per cent additional mortality. Using population viability analysis, we simulated the probability of population persistence under various scenarios of control and showed that with effective management of these invasive species, mangrove finch populations should start to recover. PMID:20194165

  8. The zebra mussel: US utility implications. [Contains Glossary

    SciTech Connect

    McMahon, R.F. )

    1990-11-01

    Dreissena polymorpha, the freshwater macrofouling zebra mussel, was introduced to Lake St. Clair, near Detroit, Michigan, in 1985. It has since spread throughout Lake Erie. Its planktonic veliger larval stage disperses on water currents and adults are transported by human and natural vectors, making it likely to spread throughout most of the United States and southern Canada except for the southwestern and southern United State, where summer water temperatures are above tolerated levels. Veligers enter raw water systems on intake currents to settle and grow to adults attached by secreted byssal threads to hard surfaces. Accumulations of adults impede flow, aggravate sedimentation and corrosion, and foul small-diameter components. Settlement occurs at flow velocities less than 1.5--2.0 m/sec. Mussels can reduce effective pipe diameters and foul intake structures, steam condensers, heat exchangers, fire protection systems, and cooling tower basins. Establishment of mussels in raw water systems should be prevented because subsequent removal is difficult and expensive. Mitigation procedures include manual removal, robotic cleaning, thermal backwashing, water jetting, application of molluscicides, and possibly line pigging and acidic chemical cleaning. Control technologies include oxidizing and non-oxidizing molluscicides, robotic cleaning, shell strainers, exposure of veligers to high voltage electrical fields, thermal backwashing and sand-filtration. The United States power industry can utilize extensive European experience with this species and domestic experience with the Asian clam in its development of effective controls for zebra mussel fouling.

  9. 18. Photographic copy of photograph (at teh offices of Finch, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Photographic copy of photograph (at teh offices of Finch, Pruyn & Company, Glen Street, Glens Falls, New York), Beach?, Photographer, June 31, 1913. Panoramic view east to southwest of the Glens Falls Dam after the 1913 flood taken from the west end of the Finch, Pruyn & Company intake structure. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

  10. 20. Photographic copy of photograph (at the offices of Finch, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. Photographic copy of photograph (at the offices of Finch, Pruyn & Company, Glen Street, Glens Falls, New York), Beach?, Photographer, November 25, 1913. View southwest to northwest of the Glens Falls Dam before activation. Intake structures for International Paper Company and Finch, Pruyn & Company are on the left and right, respectively. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

  11. Controlling zebra mussel infestations at hydroelectric plants

    SciTech Connect

    Sblendorio, R.P.; Malinchock, J.C. ); Claudi, R. )

    1991-07-01

    U.S. and Canadian utilities in the great lakes area have adopted techniques to temporarily prevent infestation of the zebra mussel in their hydro facilities, but are still looking for more permanent solutions.

  12. Introduced species, zebra mussels in North America

    USGS Publications Warehouse

    Schloesser, Don W.; Nierenberg, William A.

    1995-01-01

    The discovery of zebra mussels in North America in 1988 raised concern for water users because the species became abundant enough to obstruct the flow of water in human-made structures such as pipes and screens. This work reviews the biology, distribution, and impacts of zebra mussels in the context of its discovery in the Laurentian Great Lakes and its impending spread to most surface waters of North America.

  13. Zebra mussels invade Lake Erie muds

    USGS Publications Warehouse

    Berkman, Paul Arthur; Haltuch, Melissa A.; Tichich, Emily; Garton, David W.; Kennedy, Gregory W.; Gannon, John E.; Mackey, Scudder D.; Fuller, Jonathan A.; Liebenthal, Dale L.

    1998-01-01

    Zebra mussels (Dreissena polymorpha) originated in western Russia but have now become widespread in Europe and North America. They are widely known for their conspicuous invasion of rocks and other hard substrates in North American and European watersheds. We have found beds of zebra mussels directly colonizing sand and mud sediments each year across hundreds of square kilometres of North America's Lake Erie. This transformation of sedimentary habitats into mussel beds represents an unforeseen change in the invasive capacity of this species.

  14. Environmental DNA mapping of Zebra Mussel populations

    USGS Publications Warehouse

    Amberg, Jon; Merkes, Christopher

    2016-01-01

    Environmental DNA (eDNA) has become a popular tool for detecting aquatic invasive species, but advancements have made it possible to potentially answer other questions like reproduction, movement, and abundance of the targeted organism. In this study we developed a Zebra Mussel (Dreissena polymorpha) eDNA protocol. We then determined if this assay could be used to help determine Zebra Mussel biomass in a lake with a well-established population of Zebra Mussels and a lake with an emerging population of mussels. Our eDNA assay detected DNA of Zebra Mussels but not DNA from more than 20 other species of fish and mussels, many commonly found in Minnesota waters. Our assay did not predict biomass. We did find that DNA from Zebra Mussels accumulated in softer substrates in both lakes, even though the mussels were predominately on the harder substrates. Therefore, we concluded that eDNA may be useful to detect the presence of Zebra Mussels in these lakes but our assay/approach could not predict biomass.

  15. Zebra mussels. The assault continues

    SciTech Connect

    Lamarre, L.

    1993-09-01

    Over the past seven years, zebra mussel infestation has spread relentlessly, fouling up utility cooling intakes and other industrial operations that draw fresh water. The striped invader has flourished in all of the Great Lakes and most of the major river systems east of and including the Mississippi. It has also migrated much deeper into the South than experts anticipated and is making its way westward. Now biologists have turned up a separate, look-alike species they fear may be just as destructive. EPRI is continuing its work to improve control techniques and has published a comprehensive monitoring and control guide that outlines the best practices currently available for dealing with the mussel problem. This article reviews the results of this work.

  16. Zebra Stripes through the Eyes of Their Predators, Zebras, and Humans

    PubMed Central

    Melin, Amanda D.; Kline, Donald W.; Hiramatsu, Chihiro; Caro, Tim

    2016-01-01

    The century-old idea that stripes make zebras cryptic to large carnivores has never been examined systematically. We evaluated this hypothesis by passing digital images of zebras through species-specific spatial and colour filters to simulate their appearance for the visual systems of zebras’ primary predators and zebras themselves. We also measured stripe widths and luminance contrast to estimate the maximum distances from which lions, spotted hyaenas, and zebras can resolve stripes. We found that beyond ca. 50 m (daylight) and 30 m (twilight) zebra stripes are difficult for the estimated visual systems of large carnivores to resolve, but not humans. On moonless nights, stripes are difficult for all species to resolve beyond ca. 9 m. In open treeless habitats where zebras spend most time, zebras are as clearly identified by the lion visual system as are similar-sized ungulates, suggesting that stripes cannot confer crypsis by disrupting the zebra’s outline. Stripes confer a minor advantage over solid pelage in masking body shape in woodlands, but the effect is stronger for humans than for predators. Zebras appear to be less able than humans to resolve stripes although they are better than their chief predators. In conclusion, compared to the uniform pelage of other sympatric herbivores it appears highly unlikely that stripes are a form of anti-predator camouflage. PMID:26799935

  17. Steam treatment of zebra mussels

    SciTech Connect

    Tsou, J.; Rybarik, D.L.; Thiel, J.

    1995-06-01

    Steam injection into intake bays is a nonchemical method to control zebra mussels. This technique was demonstrated at Dairyland Power Cooperative`s J.P. Madgett Station located in Alma, Wisconsin. The project was funded by the EPRI Zebra Mussel Consortium which includes: Dairyland Power Cooperative, Central Illinois Public Service, Duke Power, Illinois Power Company, PSI Energy, Public Service Electric & Gas, and Tennessee Valley Authority. This technique can be used by other power plants with a similar problem. A contract between Electric Power Research Institute (EPRI) and Stone & Webster Engineering Corporation (Stone & Webster) was initiated in August 1994. The steam treatments were performed at the J.P. Madgett intake in Alma, Wisconsin, on September 14 and 18, 1994. The J.P. Madgett Station has two water intake bays with storage capacities of approximately 295,000 and 265,000 gallons, respectively. Each intake can be isolated, permitting either full or reduced generation depending on river temperature conditions. In addition to the intake bays, the outside fire protection loop and hydrants were also treated with the hot water from one of the bays. This paper presents the process design, piping and steam educator configurations, portable industrial boiler sizing and description, and the thermocouples to monitor the water temperature in the intake bay. The biological mortality and control test protocol and treatment results are also presented. Treatment effectiveness was 100%; however, equipment installation and operation was more problematic than anticipated. A generic computer program is developed and verified using thermal data from the test. The PC program will allow other utilities to size the boiler and estimate the heat losses from an intake bay. The treatment also provided valuable information that simplifies future applications and provides for more realistic design and installation schedules and costs.

  18. Zebra: A striped network file system

    NASA Technical Reports Server (NTRS)

    Hartman, John H.; Ousterhout, John K.

    1992-01-01

    The design of Zebra, a striped network file system, is presented. Zebra applies ideas from log-structured file system (LFS) and RAID research to network file systems, resulting in a network file system that has scalable performance, uses its servers efficiently even when its applications are using small files, and provides high availability. Zebra stripes file data across multiple servers, so that the file transfer rate is not limited by the performance of a single server. High availability is achieved by maintaining parity information for the file system. If a server fails its contents can be reconstructed using the contents of the remaining servers and the parity information. Zebra differs from existing striped file systems in the way it stripes file data: Zebra does not stripe on a per-file basis; instead it stripes the stream of bytes written by each client. Clients write to the servers in units called stripe fragments, which are analogous to segments in an LFS. Stripe fragments contain file blocks that were written recently, without regard to which file they belong. This method of striping has numerous advantages over per-file striping, including increased server efficiency, efficient parity computation, and elimination of parity update.

  19. Darwin's finches: population variation and natural selection.

    PubMed Central

    Grant, P R; Grant, B R; Smith, J N; Abbott, I J; Abbott, L K

    1976-01-01

    Van Valen's model, which relates morphological variation to ecological variation in an adaptive scheme, was investigated with individually marked and measured Darwin's finches on two adjacent Galápagos islands, Santa Cruz and Daphne Major. Results show that environmental heterogeneity is correlated with large continuous, morphological variation: variation in bill dimensions of Geospiza fortis is greater on Santa Cruz than on Daphne, as is environmental heterogeneity. Within populations of this species, different phenotypes distribute themselves in different habitat patches, select foods of different sizes and hardness, and exploit them with efficiencies that are phenotype- (bill size) dependent. These data constitute indirect evidence that natural selection has a controlling influence over the level of phenotypic variation exhibited by a population. Further evidence is that phenotypes did not survive equally well during the study period; on Daphne island G. fortis was apparently subjected to directional selection on bill tip length and G. scandens to normalizing selection on body weight and bill depth. Other factors which may have contributed to the establishment of a difference in variation between Santa Cruz and Daphne populations are the founder effect, genetic drift, and assortative mating. Annual climatic unpredictability is considered a source of environmental heterogeneity which, through its effect upon food supply, favors large morphological variation. It is predicted that species of large individual size are more influenced by this than are small species, and consequently exhibit greater size-corrected variation. The prediction is tested with data from six Geospiza species, and found to be correct. PMID:1061123

  20. Diversity of feather mites (Acari: Astigmata) on Darwin's finches.

    PubMed

    Villa, Scott M; Le Bohec, Céline; Koop, Jennifer A H; Proctor, Heather C; Clayton, Dale H

    2013-10-01

    Feather mites are a diverse group of ectosymbionts that occur on most species of birds. Although Darwin's finches are a well-studied group of birds, relatively little is known about their feather mites. Nearly 200 birds across 9 finch species, and from 2 locations on Santa Cruz Island, Galápagos, were dust-ruffled during the 2009 breeding season. We found 8 genera of feather mites; the most prevalent genus was Mesalgoides (53-55%), followed by Trouessartia (40-45%), Amerodectes and Proctophyllodes (26-33%), Xolalgoides (21-27%), Analges and Strelkoviacarus (0-6%), and Dermoglyphus (2-4%). There was no evidence for microclimatic effects (ambient temperature and relative humidity) on mite diversity. Host body mass was significantly correlated with mean feather mite abundance across 7 of 8 well-sampled species of finches. Certhidea olivacea, the smallest species, did not fit this pattern and had a disproportionately high number of mites for its body mass.

  1. Causes of lifetime fitness of Darwin's finches in a fluctuating environment.

    PubMed

    Grant, Peter R; Grant, B Rosemary

    2011-01-11

    The genetic basis of variation in fitness of many organisms has been studied in the laboratory, but relatively little is known of fitness variation in natural environments or its causes. Lifetime fitness (recruitment) may be determined solely by producing many offspring, modified by stochastic effects on their subsequent survival up to the point of breeding, or by an additional contribution made by the high quality of the offspring owing to nonrandom mate choice. To investigate the determinants of lifetime fitness, we measured offspring production, longevity, and lifetime number of mates in four cohorts of two long-lived species of socially monogamous Darwin's finch species, Geospiza fortis and G. scandens, on the equatorial Galápagos Island of Daphne Major. Regression analysis showed that the lifetime production of fledglings was predicted by lifetime number of clutches and that recruitment was predicted by lifetime number of fledglings and longevity. There was little support for a hypothesis of selective mating by females. The offspring sired by extrapair mates were no more fit in terms of recruitment than were half-sibs sired by social mates. These findings provide insight into the evolution of life history strategies of tropical birds. Darwin's finches deviate from the standard tropical pattern of a slow pace of life by combining tropical (long lifespan) and temperate (large clutch size) characteristics. Our study of fitness shows why this is so in terms of selective pressures (fledgling production and adult longevity) and ecological opportunities (pulsed food supply and relatively low predation). PMID:21199941

  2. Determination of plasma parameters in solar zebra radio sources

    NASA Astrophysics Data System (ADS)

    Karlický, M.; Yasnov, L. V.

    2015-09-01

    Aims: We present a new method for determining the magnetic field strength and plasma density in the solar zebra radio sources. Methods: Using the double plasma resonance (DPR) model of the zebra emission, we analytically derived the equations for computing the gyroharmonic number s of selected zebra lines and then solved these equations numerically. Results: The method was successfully tested on artificially generated zebras and then applied to observed ones. The magnetic field strength and plasma density in the radio sources were determined. Simultaneously, we evaluated the parameter Lnb = 2Lb/ (2Ln - Lb), where Ln and Lb are the characteristic scale-heights of the plasma density and magnetic field strength in the zebra source, respectively. Computations show that the maximum frequency of the low-polarized zebras is about 8 GHz, in very good agreement with observations. For the high-polarized zebras, this limit is about four times lower. Microwave zebras are preferentially generated in the regions with steep gradients of the plasma density, such as in the transition region. In models with smaller density gradients, such as those with a barometric density profile, the microwave zebras cannot be produced owing to the strong bremsstrahlung and cyclotron absorptions. We also show that our DPR model is able to explain the zebras with frequency-equidistant zebra lines.

  3. Are Horses Like Zebras, or Vice Versa? Children's Sensitivity to the Asymmetries of Directional Comparisons.

    PubMed

    Chestnut, Eleanor K; Markman, Ellen M

    2016-01-01

    Adults exhibit strong preferences when framing symmetrical relations. Adults prefer, for example, "A zebra is like a horse" to "A horse is like a zebra," and "The bicycle is near the building" to "The building is near the bicycle." This is because directional syntax requires more typical or prominent items (i.e., reference points) to be placed in the complement position. Three experiments with children ages 4-8 (N = 181) explored whether children share this sensitivity to directional syntax. Children of this age showed an incipient preference for framing reference points as complements. Stating, "Girls do math as well as boys," which frames boys as the reference point for girls, may therefore actually teach children that boys set the standard.

  4. Transient coupling of Ng-CAM expression to NgCAM-dependent calcium signaling during migration of new neurons in the adult songbird brain.

    PubMed

    Goldman, S A; Williams, S; Barami, K; Lemmon, V; Nedergaard, M

    1996-01-01

    The adult avian forebrain continues to generate neurons from subependymal zone (SZ) precursor cells, whose neuronal progeny migrate into the brain upon radial guide fibers. These neurons express the immunoglobulin-family adhesion molecule NgCAM, and their migration in culture is disrupted by anti-NgCAM Fab. Confocal imaging of adult zebra finch SZ loaded with the calcium indicator fluo-3, as well as ratio imaging with the indicator fura-2, revealed that migrating new neurons responded to microgram amounts of NgCAM with reversible increments in cytosolic calcium. The calcium response to NgCAM antigen was developmentally restricted, in that it was only manifested by neurons for roughly the 3- to 4-day period between 6 and 9 DIV, even though NgCAM expression persisted tonically thereafter. The period during which NgCAM elicited a calcium signal corresponded to the postmitotic age at which new, bipolar neurons leave the adult SZ to enter the brain parenchyma in vivo. Accordingly, the calcium response to NgCAM was largely limited to morphologically bipolar cells. Anti-NgCAM IgG also evoked a neuronal calcium signal over the same restricted period that NgCAM protein exerted its effect. These findings suggest a dynamic coupling and uncoupling of calcium-dependent signal transduction pathways to a stably expressed surface adhesion molecule, whose function in a given neuron may therefore evolve with cellular maturation.

  5. EFFECTS OF EXOGENOUS ESTROGEN ON MATE SELECTION OF HOUSE FINCHES

    EPA Science Inventory

    Concern about the potential for endocrine disrupting chemicals to interfere with normal breeding behaviors of wildlife has prompted this study of effects of exogenous estrogen on mate selection in songbirds. The house finch (Carpodacus mexicanus) was selected as a model as it is ...

  6. EFFECTS OF EXTROGENOUS ESTROGEN ON MATE SELECTION OF HOUSE FINCHES

    EPA Science Inventory

    Effects of exogenous estrogen on mate selection of house finches. Clark, J., Fairbrother, A*. Parametrix, Inc., Corvallis, OR; Brewer, L., EBA, Inc., Sisters, OR; Bennett, R.S., USEPA, Mid-Continent Ecology Division, Duluth, MN.

    Concern about the potential for endocrine...

  7. Affine transformations capture beak shape variation in Darwin's Finches

    NASA Astrophysics Data System (ADS)

    Brenner, Michael; Campas, Otger; Mallarino, Riccardo; Abzhanov, Arhat

    2009-11-01

    Evolution by natural selection has resulted in extraordinary morphological complexity of living organisms, whose description has thus far defied any precise mathematical characterization linked to the underlying developmental genetics. Here we demonstrate that the morphological diversity of the beaks of Darwin's finches, the classical example of adaptive morphological radiation, is quantitatively accounted for through the mathematical group of affine transformations. Specifically, we show that all beak shapes of Ground Finches (genus Geospiza) are related by scaling transformations (a subgroup of the affine group), and the same scheme occurs for all the beak shapes of Tree and Warbler finches. This analysis shows that the beak shapes within each of these groups differ only by their scales, such as length and depth, each of which is knownto be under genetic control.The complete morphological variability within the beaks of Darwin's finches can be explained by extending the scaling transformations to the entire affine group, by including shear transformations. Altogether our results suggest that the mathematical theory of groups can help decode morphological variability, and points to a potentially hierarchical structure of morphological diversity and the underlying developmental processes.

  8. Zebra Mussel Monitoring and Control Guide

    SciTech Connect

    Not Available

    1992-12-01

    The Electric Power Research Institute (EPRI) Zebra Mussel Monitoring and Control Guide is a comprehensive compilation of US and European practices as reported in the open literature as of the end of 1992. EPRI considers the guide to be a living' document and will update it periodically in order to provide results of current research on chemical and nonchemical control technologies and utility experiences. The zebra mussel has infested all of the Great Lakes and other major rivers and waterways and is positioned to spread even more to the adjoining river basins. The impact of the zebra mussel on industrial power plantsis as a biofouler that clogs water systems and heat exchangers. This EPRI guideline identifies the zebra mussel, discusses its distribution in the United States, presents the potential threats to power plants, and presents the methods to initiate monitoring and control programs. Both preventive and corrective measures are presented. Preventive measures include various monitoring methods to initiate control techniques. The control techniques include both chemical and nonchemical together with combining techniques. Corrective methods include operational considerations, chemical cleaning, and mechanical/physical cleaning. It also may be possible to incorporate design changes, such as open to closed-loop backfit, backflushing, or pretreatment for closed systems. Various appendices are included that contain specifications to aid utilities in implementing several of the monitoring and control technologies, results of chemical evaluations at Cleveland Electric Illuminating Company plants, and data on the fate of various commercial molluscicides.

  9. Motion camouflage induced by zebra stripes.

    PubMed

    How, Martin J; Zanker, Johannes M

    2014-06-01

    The functional significance of the zebra coat stripe pattern is one of the oldest questions in evolutionary biology, having troubled scientists ever since Charles Darwin and Alfred Russel Wallace first disagreed on the subject. While different theories have been put forward to address this question, the idea that the stripes act to confuse or 'dazzle' observers remains one of the most plausible. However, the specific mechanisms by which this may operate have not been investigated in detail. In this paper, we investigate how motion of the zebra's high contrast stripes creates visual effects that may act as a form of motion camouflage. We simulated a biologically motivated motion detection algorithm to analyse motion signals generated by different areas on a zebra's body during displacements of their retinal images. Our simulations demonstrate that the motion signals that these coat patterns generate could be a highly misleading source of information. We suggest that the observer's visual system is flooded with erroneous motion signals that correspond to two well-known visual illusions: (i) the wagon-wheel effect (perceived motion inversion due to spatiotemporal aliasing); and (ii) the barber-pole illusion (misperceived direction of motion due to the aperture effect), and predict that these two illusory effects act together to confuse biting insects approaching from the air, or possibly mammalian predators during the hunt, particularly when two or more zebras are observed moving together as a herd. PMID:24368147

  10. Motion camouflage induced by zebra stripes.

    PubMed

    How, Martin J; Zanker, Johannes M

    2014-06-01

    The functional significance of the zebra coat stripe pattern is one of the oldest questions in evolutionary biology, having troubled scientists ever since Charles Darwin and Alfred Russel Wallace first disagreed on the subject. While different theories have been put forward to address this question, the idea that the stripes act to confuse or 'dazzle' observers remains one of the most plausible. However, the specific mechanisms by which this may operate have not been investigated in detail. In this paper, we investigate how motion of the zebra's high contrast stripes creates visual effects that may act as a form of motion camouflage. We simulated a biologically motivated motion detection algorithm to analyse motion signals generated by different areas on a zebra's body during displacements of their retinal images. Our simulations demonstrate that the motion signals that these coat patterns generate could be a highly misleading source of information. We suggest that the observer's visual system is flooded with erroneous motion signals that correspond to two well-known visual illusions: (i) the wagon-wheel effect (perceived motion inversion due to spatiotemporal aliasing); and (ii) the barber-pole illusion (misperceived direction of motion due to the aperture effect), and predict that these two illusory effects act together to confuse biting insects approaching from the air, or possibly mammalian predators during the hunt, particularly when two or more zebras are observed moving together as a herd.

  11. Research continues on zebra mussel control

    SciTech Connect

    Not Available

    1993-04-01

    Researchers are working on many fronts to learn methods for controlling and combatting zebra mussels, a species of mussel that can attach to the inside of water intakes at hydroelectric and thermal power plants, and can reduce or block water flow. Biologists at the University of Toledo in Ohio report that compounds from the African soapberry plant called lemmatoxins are lethal to zebra mussels. In laboratory tests, researchers have determined 1 to 2 milligrams of purified lemmatoxins per liter will kill the mussels. In field tests, biologist Harold Lee flushed water through a mussel-infested pipe. He found that the berry extract killed mussels in four to eight hours, making continuous treatment of water intake pipes unnecessary, according to a report in New Scientists. The University of Toledo participated in another project, funded by the American Water Works Association Research Foundation. That project team included the cities of Toledo and Cleveland, Ohio, Finkbeiner, Pettis Strout, Ltd. consulting engineers, and researchers from Ohio's Case Western Reserve University. The team identified a chemical oxidant, sodium hypochlorite, as a cost-effective agent for controlling zebra mussels at water treatment plant intakes. Toledo has used the sodium hypochlorite and reports the chemical has cleared colonies of zebra mussels that had attached to the intake of its water treatment plant.

  12. Control of zebra mussels with ultraviolet radiation

    SciTech Connect

    Lewis, D.P.

    1998-07-01

    This paper presents the results of research on the effects of low and medium pressure ultraviolet (UV) radiation on zebra mussel mortality carried out between 1992 and 1995. An initial 1992 study, carried out by Aquatic Sciences (ASI), showed that flow-through UV systems have the ability to kill zebra mussels and prevent them from attaching to downstream surfaces. However, this work did not include expanded testing to determine the limitations of UV radiation at higher flow rates or to further define effective working parameters. The 1994 study was carried out at the Lennox Thermal Generating Station (TGS) of Ontario Hydro in Kingston, Ontario. This study involved the testing of two open channel UV systems (medium and low pressure) in an effort to determine flow rates and volumes for which UV disinfection would be effective and practical for the prevention of zebra mussel infestation. It was recommended that medium pressure (MP) and low pressure (LP) UV systems be tested for their ability to control downstream settlement of zebra mussels, in flow-through trials.

  13. Phylogeny of Darwin’s finches as revealed by mtDNA sequences

    PubMed Central

    Sato, Akie; O’hUigin, Colm; Figueroa, Felipe; Grant, Peter R.; Grant, B. Rosemary; Tichy, Herbert; Klein, Jan

    1999-01-01

    Darwin’s finches comprise a group of passerine birds first collected by Charles Darwin during his visit to the Galápagos Archipelago. The group, a textbook example of adaptive radiation (the diversification of a founding population into an array of species differentially adapted to diverse environmental niches), encompasses 14 currently recognized species, of which 13 live on the Galápagos Islands and one on the Cocos Island in the Pacific Ocean. Although Darwin’s finches have been studied extensively by morphologists, ecologists, and ethologists, their phylogenetic relationships remain uncertain. Here, sequences of two mtDNA segments, the cytochrome b and the control region, have been used to infer the evolutionary history of the group. The data reveal the Darwin’s finches to be a monophyletic group with the warbler finch being the species closest to the founding stock, followed by the vegetarian finch, and then by two sister groups, the ground and the tree finches. The Cocos finch is related to the tree finches of the Galápagos Islands. The traditional classification of ground finches into six species and tree finches into five species is not reflected in the molecular data. In these two groups, ancestral polymorphisms have not, as yet, been sorted out among the cross-hybridizing species. PMID:10220425

  14. Phylogenetic relationships and morphological diversity in Darwin's finches and their relatives.

    PubMed

    Burns, Kevin J; Hackett, Shannon J; Klein, Nedra K

    2002-06-01

    Despite the importance of Darwin's finches to the development of evolutionary theory, the origin of the group has only recently been examined using a rigorous, phylogenetic methodology that includes many potential outgroups. Knowing the evolutionary relationships of Darwin's finches to other birds is important for understanding the context from which this adaptive radiation arose. Here we show that analysis of mitochondrial DNA sequence data from the cytochrome b gene confirm that Darwin's finches are monophyletic. In addition, many taxa previously proposed as the sister taxon to Darwin's finches can be excluded as their closest living relative. Darwin's finches are part of a well-supported monophyletic group of species, all of which build a domed nest. All but two of the non-Darwin's finches included in this clade occur on Caribbean islands and most are Caribbean endemics. These close relatives of Darwin's finches show a diversity of bill types and feeding behaviors similar to that observed among Darwin's finches themselves. Recent studies have shown that adaptive evolution in Darwin's finches occurred relatively quickly. Our data show that among the relatives of Darwin's finches, the evolution of bill diversity was also rapid and extensive.

  15. Phylogeny of Darwin's finches as revealed by mtDNA sequences.

    PubMed

    Sato, A; O'hUigin, C; Figueroa, F; Grant, P R; Grant, B R; Tichy, H; Klein, J

    1999-04-27

    Darwin's finches comprise a group of passerine birds first collected by Charles Darwin during his visit to the Galápagos Archipelago. The group, a textbook example of adaptive radiation (the diversification of a founding population into an array of species differentially adapted to diverse environmental niches), encompasses 14 currently recognized species, of which 13 live on the Galápagos Islands and one on the Cocos Island in the Pacific Ocean. Although Darwin's finches have been studied extensively by morphologists, ecologists, and ethologists, their phylogenetic relationships remain uncertain. Here, sequences of two mtDNA segments, the cytochrome b and the control region, have been used to infer the evolutionary history of the group. The data reveal the Darwin's finches to be a monophyletic group with the warbler finch being the species closest to the founding stock, followed by the vegetarian finch, and then by two sister groups, the ground and the tree finches. The Cocos finch is related to the tree finches of the Galápagos Islands. The traditional classification of ground finches into six species and tree finches into five species is not reflected in the molecular data. In these two groups, ancestral polymorphisms have not, as yet, been sorted out among the cross-hybridizing species.

  16. Physical Conditions in the Source Region of a Zebra Structure

    NASA Astrophysics Data System (ADS)

    Yasnov, L. V.; Karlický, M.; Stupishin, A. G.

    2016-07-01

    We analyze the physical conditions in the source region of a zebra structure, observed with the Ondřejov radiospectrograph during the 1 August 2010 solar flare. To determine the gyro-frequency harmonic numbers of the observed zebra lines, we compute the magnetic field strength, the electron density, and their spatial scales in the source region of the zebra structure. The region where the flare occurred is analyzed using EUV (171 Å and 335 Å) observations. To determine the conditions in the zebra source region, the magnetic field structure is reconstructed using observed photospheric magnetic field data. By computing the dependence of the magnetic field vs. height in this reconstruction and by comparing the magnetic field strength derived from the zebra structure, we determine the dependence of the electron density vs. height in the zebra source-region. We identify the loops where the zebra structure was generated at heights of about 2.5 - 3.3 Mm. Assuming the barometric law for the electron density, we determine the temperature in the zebra source-region to be T ≈ 2.0 × 104 K. Comparing the obtained values of the temperature and electron density in the zebra source-region with a model of the solar atmosphere, we find that the zebra structure was generated in the transition region, in agreement with our previous results.

  17. Physical Conditions in the Source Region of a Zebra Structure

    NASA Astrophysics Data System (ADS)

    Yasnov, L. V.; Karlický, M.; Stupishin, A. G.

    2016-08-01

    We analyze the physical conditions in the source region of a zebra structure, observed with the Ondřejov radiospectrograph during the 1 August 2010 solar flare. To determine the gyro-frequency harmonic numbers of the observed zebra lines, we compute the magnetic field strength, the electron density, and their spatial scales in the source region of the zebra structure. The region where the flare occurred is analyzed using EUV (171 Å and 335 Å) observations. To determine the conditions in the zebra source region, the magnetic field structure is reconstructed using observed photospheric magnetic field data. By computing the dependence of the magnetic field vs. height in this reconstruction and by comparing the magnetic field strength derived from the zebra structure, we determine the dependence of the electron density vs. height in the zebra source-region. We identify the loops where the zebra structure was generated at heights of about 2.5 - 3.3 Mm. Assuming the barometric law for the electron density, we determine the temperature in the zebra source-region to be T ≈ 2.0 × 104~K. Comparing the obtained values of the temperature and electron density in the zebra source-region with a model of the solar atmosphere, we find that the zebra structure was generated in the transition region, in agreement with our previous results.

  18. In vitro maturation and fertilization of oocytes recovered from free-ranging Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae).

    PubMed

    Meintjes, M; Bezuidenhout, C; Bartels, P; Visser, D S; Meintjes, J; Loskutoff, N M; Fourie, F L; Barry, D M; Godke, R A

    1997-09-01

    A noninvasive repeatable method to harvest oocytes for in vitro fertilization (IVF) could potentially be used to assist reproduction in endangered equid species. The objectives of this study were to evaluate a specific transvaginal ultrasound-guided oocyte recovery procedure for use in zebra mares and the general applicability of IVF procedures in zebra. Ovaries were collected from Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae) mares at routine culling for Expt. I. Of the 144 oocytes recovered from these ovaries, 70% were of excellent quality. No significant difference in oocyte quality was found between the two zebra species. Zona drilling was performed on in vitro-matured oocytes prior to IVF. Epididymal sperm from culled Burchell's zebra stallions were used for IVF. The sperm either were exposed to calcium ionophore or were not treated and served as a control. In vitro fertilized oocytes were then co-cultured with zebra granulosa cells (ZGC) or with bovine oviduct cells (BOC) for up to 8 days. Overall, a 38% cleavage rate was obtained with 16% of sperm-exposed oocytes developing to the morula or blastocyst stage. All of the embryos that developed to at least the morula stage were cultured on BOC; whereas, none of those cultured on ZGC reached the morula stage during the same interval. Cleavage rates of oocytes inseminated with ionophore-treated or with control sperm were not significantly different, suggesting that ionophore treatment of epididymal sperm for IVF in these zebra species may be redundant. In Expt. II, 10 transvaginal ultrasound-guided oocyte aspiration procedures on five captive Burchell's zebra mares recovered a total of 33 oocytes (6.6 oocytes/female) of which 94% were considered viable. This approach may be an attractive means of producing gametes for assisted reproduction in endangered species. Furthermore, results from this study indicate that IVF may become a means of producing offspring from zebra and other

  19. A beak size locus in Darwin's finches facilitated character displacement during a drought.

    PubMed

    Lamichhaney, Sangeet; Han, Fan; Berglund, Jonas; Wang, Chao; Almén, Markus Sällman; Webster, Matthew T; Grant, B Rosemary; Grant, Peter R; Andersson, Leif

    2016-04-22

    Ecological character displacement is a process of morphological divergence that reduces competition for limited resources. We used genomic analysis to investigate the genetic basis of a documented character displacement event in Darwin's finches on Daphne Major in the Galápagos Islands: The medium ground finch diverged from its competitor, the large ground finch, during a severe drought. We discovered a genomic region containing the HMGA2 gene that varies systematically among Darwin's finch species with different beak sizes. Two haplotypes that diverged early in the radiation were involved in the character displacement event: Genotypes associated with large beak size were at a strong selective disadvantage in medium ground finches (selection coefficient s = 0.59). Thus, a major locus has apparently facilitated a rapid ecological diversification in the adaptive radiation of Darwin's finches. PMID:27102486

  20. Effect of dose on house finch infection with western equine encephalomyelitis and St. Louis encephalitis viruses.

    PubMed

    Reisen, William K; Chiles, Robert; Martinez, Vincent; Fang, Ying; Green, Emily; Clark, Sharon

    2004-09-01

    House finches, Carpodacus mexicanus, were experimentally infected with high and standard doses of western equine encephalomyelitis virus (WEEV) or St. Louis encephalitis virus (SLEV) to determine whether high doses would produce an elevated viremia response and a high frequency of chronic infections. Finches inoculated with approximately100,000 plaque forming units (PFU) of WEEV or SLEV produced viremia and antibody responses similar to those in finches inoculated with approximately 100 PFU of WEEV or 1000 PFU of SLEV, the approximate quantities of virus expectorated by blood-feeding Culex tarsalis Coquillett. Infected finches were held through winter and then necropsied. Only one finch inoculated with the high dose of SLEV developed a chronic infection. Our data indicated that elevated infectious doses of virus may not increase the viremia level or the frequency of chronic infection in house finches.

  1. CA/CPS: A Communications ZEBRA implementation using CPS

    SciTech Connect

    Roberts, L.A.

    1991-05-01

    CZ/CPS is an implementation of the Communications ZEBRA distributed computing environment utilizing the CPS communications protocol. CZ/CPS is intended for parallelization of high energy physics application programs using the CERN Program Library memory and data structure management features. CZ/CPS provides transparent communication of ZEBRA data structures among cooperative processes using standard interfaces for ZEBRA I/O. Examples of usage in a CPS HBOOK4 and GEANT3 application are provided.

  2. Comparative morphology of zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel sperm: Light and electron microscopy

    USGS Publications Warehouse

    Walker, G.K.; Black, M.G.; Edwards, C.A.

    1996-01-01

    Adult zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels were induced to release large quantities of live spermatozoa by the administration of 5-hydroxytryptamine (serotonin). Sperm were photographed alive using phase-contrast microscopy and were fixed subsequently with glutaraldehyde followed by osmium tetroxide for eventual examination by transmission or scanning electron microscopy. The sperm of both genera are of the ect-aquasperm type. Their overall dimensions and shape allow for easy discrimination at the light and scanning electron microscopy level. Transmission electron microscopy of the cells reveals a barrel-shaped nucleus in zebra mussel sperm and an elongated nucleus in quagga mussel sperm. In both species, an acrosome is cradled in a nuclear fossa. The ultrastructure of the acrosome and axial body, however, is distinctive for each species. The structures of the midpiece are shown, including a unique mitochondrial "skirt" that includes densely packed parallel cristae and extends in a narrow sheet from the mitochondria.

  3. Zebras and Biting Flies: Quantitative Analysis of Reflected Light from Zebra Coats in Their Natural Habitat

    PubMed Central

    Britten, Kenneth H.; Thatcher, Timothy D.; Caro, Tim

    2016-01-01

    Experimental and comparative evidence suggests that the striped coats of zebras deter biting fly attack, but the mechanisms by which flies fail to target black-and-white mammals are still opaque. Two hypotheses have been proposed: stripes might serve either to defeat polarotaxis or to obscure the form of the animal. To test these hypotheses, we systematically photographed free-living plains zebras in Africa. We found that black and white stripes both have moderate polarization signatures with a similar angle, though the degree (magnitude) of polarization in white stripes is lower. When we modeled the visibility of these signals from different distances, we found that polarization differences between stripes are invisible to flies more than 10 m away because they are averaged out by the flies’ low visual resolution. At any distance, however, a positively polarotactic insect would have a distinct signal to guide its visual approach to a zebra because we found that polarization of light reflecting from zebras is higher than from surrounding dry grasses. We also found that the stripes themselves are visible to flies at somewhat greater distances (up to 20 m) than the polarization contrast between stripes. Together, these observations support hypotheses in which zebra stripes defeat visually guided orienting behavior in flies by a mechanism independent of polarotaxis. PMID:27223616

  4. Zebras and Biting Flies: Quantitative Analysis of Reflected Light from Zebra Coats in Their Natural Habitat.

    PubMed

    Britten, Kenneth H; Thatcher, Timothy D; Caro, Tim

    2016-01-01

    Experimental and comparative evidence suggests that the striped coats of zebras deter biting fly attack, but the mechanisms by which flies fail to target black-and-white mammals are still opaque. Two hypotheses have been proposed: stripes might serve either to defeat polarotaxis or to obscure the form of the animal. To test these hypotheses, we systematically photographed free-living plains zebras in Africa. We found that black and white stripes both have moderate polarization signatures with a similar angle, though the degree (magnitude) of polarization in white stripes is lower. When we modeled the visibility of these signals from different distances, we found that polarization differences between stripes are invisible to flies more than 10 m away because they are averaged out by the flies' low visual resolution. At any distance, however, a positively polarotactic insect would have a distinct signal to guide its visual approach to a zebra because we found that polarization of light reflecting from zebras is higher than from surrounding dry grasses. We also found that the stripes themselves are visible to flies at somewhat greater distances (up to 20 m) than the polarization contrast between stripes. Together, these observations support hypotheses in which zebra stripes defeat visually guided orienting behavior in flies by a mechanism independent of polarotaxis. PMID:27223616

  5. Zebras and Biting Flies: Quantitative Analysis of Reflected Light from Zebra Coats in Their Natural Habitat.

    PubMed

    Britten, Kenneth H; Thatcher, Timothy D; Caro, Tim

    2016-01-01

    Experimental and comparative evidence suggests that the striped coats of zebras deter biting fly attack, but the mechanisms by which flies fail to target black-and-white mammals are still opaque. Two hypotheses have been proposed: stripes might serve either to defeat polarotaxis or to obscure the form of the animal. To test these hypotheses, we systematically photographed free-living plains zebras in Africa. We found that black and white stripes both have moderate polarization signatures with a similar angle, though the degree (magnitude) of polarization in white stripes is lower. When we modeled the visibility of these signals from different distances, we found that polarization differences between stripes are invisible to flies more than 10 m away because they are averaged out by the flies' low visual resolution. At any distance, however, a positively polarotactic insect would have a distinct signal to guide its visual approach to a zebra because we found that polarization of light reflecting from zebras is higher than from surrounding dry grasses. We also found that the stripes themselves are visible to flies at somewhat greater distances (up to 20 m) than the polarization contrast between stripes. Together, these observations support hypotheses in which zebra stripes defeat visually guided orienting behavior in flies by a mechanism independent of polarotaxis.

  6. Forecasting the expansion of zebra mussels in the United States.

    PubMed

    Bossenbroek, Jonathan M; Johnson, Ladd E; Peters, Brett; Lodge, David M

    2007-06-01

    Because zebra mussels spread rapidly throughout the eastern United States in the late 1980s and early 1990s, their spread to the western United States has been expected. Overland dispersal into inland lakes and reservoirs, however, has occurred at a much slower rate than earlier spread via connected, navigable waterways. We forecasted the potential western spread of zebra mussels by predicting the overland movement of recreational boaters with a production-constrained gravity model. We also predicted the potential abundance of zebra mussels in two western reservoirs by comparing their water chemistry characteristics with those of water bodies with known abundances of zebra mussels. Most boats coming from waters infested with zebra mussels were taken to areas that already had zebra mussels, but a small proportion of such boats did travel west of the 100th meridian. If zebra mussels do establish in western U.S. water bodies, we predict that population densities could achieve similar levels to those in the Midwestern United States, where zebra mussels have caused considerable economic and ecological impacts. Our analyses suggest that the dispersal of zebra mussels to the western United States is an event of low probability but potentially high impact on native biodiversity and human infrastructure. Combining these results with economic analyses could help determine appropriate investment levels in prevention and control strategies.

  7. Chlorine dioxide treatment for zebra mussel control

    SciTech Connect

    Rybarik, D.; Byron, J.; Germer, M.

    1995-06-01

    Chlorine is recognized and commonly used biocide for power plant cooling water and service water treatment programs, including the control of zebra mussels. Chlorine dioxide has recently become a popular method of zebra mussel control because of its economy, safety, environmental acceptability, and effectiveness when compared to other mussel control methods. This control technique was recently demonstrated at Dairyland Power Cooperative`s Alma Generating Station on the east bank of the upper Mississippi River in Alma, Wisconsin. The project was assisted with EPRI Tailored Collaboration Program funds. The Dairyland Power Alam Generating Station consists of five generating units that utilize raw, untreated Mississippi River water for condenser, circulating, and service water supplies. The first units were built in 1947, with the final and largest unit being completed in 1960. Total station generating capacity is 200 MW. Because of recent increases in the zebra mussel density at the station intake, Dairyland Power selected the team of Nalco and Rio Linda to perform a chlorine dioxide treatment of the station`s new water systems to eradicate and control the mussels before their presence created operational difficulties. This paper will present the results of the treatment including treatment theory, design and construction of the treatment system, the method of chlorine dioxide generation, treatment concentration, analytical methods o monitoring chlorine dioxide generation, residuals and trihalomethane (THM) concentrations, protocol for monitoring treatment mortality, and the effects of chlorine dioxide and detoxification on other water chemistry parameters and equipment materials. The goal of this paper is to inform and assist users with establishing consistent and uniform practices for safely utilizing and monitoring chlorine dioxide in the eradication and control of zebra mussels.

  8. Stravation tolerance of zebra mussels, Dreissena polymorpha

    SciTech Connect

    Chase, R.; McMahon, R.F.

    1995-06-01

    Samples of zebra mussels, Dreissena polymorpha (n=30), were held without food at 5{degrees}, 15{degrees}, or 25{degrees}C and examined daily for mortality. Further samples of 210 mussels at each test temperature were periodically subsampled (n=10) throughout the starvation period. Tissues and shells of sampled specimens were dried to a constant weight. Zebra mussels held at 25{degrees}C experienced 100% mortality after 166 days of starvation while mussels at 15{degrees}C experienced 100% mortality after 545 days. A mortality of 60% was recorded in mussels after 524 days at 5{degrees}C. Dry shell weight (DSW) of starving zebra mussels at 25{degrees}C remained constant; at 15{degrees}C, DSW increased, likely due to deposition of new shell without increase in length. At 5{degrees}C DSW decreased possibly due to the high solubility of shell calcium carbonate at this low temperature. Dry tissue weight (DTW) decreased linearly during starvation at all test temperatures with the rate of DTW loss increasing at higher holding temperatures. Estimated percent tissue biomass reductions in a 20 mm long starved individual were 73.8% after 132 days at 25{degrees}C, 68.9% after 545 days at 15{degrees}C and 61.6% after 516 days at 5{degrees}C. When DTW loss rates were converted to O{sub 2} consumption rates (O{sub 2}), the O{sub 2} of a 20 mm long mussel was estimated to be 22.2% of prestarvation O{sub 2} at 25{degrees}C, 11.0% at 15{degrees}C and 10.2% at 5{degrees}C. Major reduction in metabolic demand in starving zebra mussels at low temperatures allows overwintering without appreciable loss of organic energy stores.

  9. Outbreak of herpesviral conjunctivitis and respiratory disease in gouldian finches.

    PubMed

    Paulman, A; Lichtensteiger, C A; Kohrt, L J

    2006-11-01

    An outbreak of tracheitis, sinusitis, and conjunctivitis, originating in recently imported birds, caused high morbidity and mortality in a flock of finches in Central Illinois. Although several species were present, Gouldian finches (Erythrura [Chloebia] gouldiae) were most commonly and severely affected. Birds submitted for necropsy displayed microscopic lesions characteristic of herpesviral infection, including epithelial cytomegaly and karyomegaly with basophilic, intranuclear inclusion bodies in the nasopharynx, sinuses, trachea, parabronchi, conjunctiva, and occasionally the lacrimal gland or proximal proventricular glands. Viral particles consistent with herpesvirus were visualized within affected epithelial cells with electron microscopy. Based on a partial sequence of the viral DNA polymerase gene, this virus was found to be identical to a herpesvirus previously implicated in a similar outbreak in Canada and is most likely an alphaherpesvirus.

  10. Zebra mussel control using acoustic energy

    SciTech Connect

    Tiller, G.W.; Gaucher, T.A.; Menezes, J.K.; Dolat, S.W. )

    1992-01-01

    A practical and economical device or method that reduces zebra mussel colonization without detrimental side effects is highly desirable. An ideal method is one that could be installed near, on, or in existing raw water intakes and conduits. It must have a known effect that is limited to a defined area, should have maximum effects on a targeted species, and preferably have a low life cycle cost than the current alternative methods of control and maintenance. Underwater sound could be such a desirable solution, if found to be an effective control measure for zebra mussels. Although sound most often applies specifically to acoustic energy that is audible to humans, 20 Hertz (Hz) to 20 kiloHertz (kHz), in this report we will use the terms sound and acoustic to include acoustic energy between 100 Hz and 100 MegaHertz (MHz). This research on zebra mussel biofouling is designed to effect the early developmental stages in the life cycle of Dreissena polymorpha (Pallas). Vulnerable stages in the development of D. polymorpha that might yield to site-specific acoustic deterrence measures include the free-swimming larval veliger stage, the postveliger pre-attachment demersal stage, and the immediate post-attachment stage. The proposed applications include surface treatment to prevent, reduce or eliminate colonization on underwater structures, and the stream treatment to reduce or eliminate (destroy) mussel larvae entrained in a moving volume of water.

  11. Zebra mussel control with backwash filtration

    SciTech Connect

    Dardeau, E.A. Jr.; Bivens, T.

    1995-12-31

    Zebra Mussels (Dreissena polymorpha) were found in North American waters in 1988 at Lake St. Clair, Michigan, when a ship from a European freshwater port released its ballast water. These organisms quickly spread from the Great Lakes to many midwestern, eastern, and southern streams and lakes. As macrofoulers, they quickly colonize new areas on many natural and artificial substrates. Zebra mussels clog intakes, piping, and screens. Power production facilities that withdraw large quantities of raw water to generate electricity and cool critical components are especially vulnerable. Many control strategies have been proposed and tested; however, not all of them are environmentally acceptable. The US Army Corps of Engineers, under the auspices of the Nonindigenous Aquatic Nuisance Prevention and Control Act of 1990, has initiated a research program to control zebra mussels at public facilities. One test being conducted under this research program is a cooperative effort between the Corps` Nashville District, the Corps` Waterways Experiment Station, and several other agencies. The test involves the design and test of a backwash filtration system for a hydropower project in the Cumberland River Basin. The preliminary design, based on lessons learned from associated tests, is discussed. In addition, recommendations for future use are presented.

  12. 17. Photographic copy of photograph (at the offices of Finch, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Photographic copy of photograph (at the offices of Finch, Pruyn & Company, Glen Street, Glens Falls, New York), Beach?, Photographer, March 28, 1913. Panoramic view of the Hudson River at Glens Falls during the March 1913 flood showing overtopped Glens Falls Dam and washed out bridge. Facing southwest. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

  13. Pedigrees, assortative mating and speciation in Darwin's finches.

    PubMed

    Grant, Peter R; Grant, B Rosemary

    2008-03-22

    Pedigree analysis is a useful tool in the study of speciation. It can reveal trans-generational influences on the choice of mates. We examined mating patterns in a population of Darwin's medium ground finches (Geospiza fortis) on Daphne Major Island to improve our understanding of how a barrier to the exchange of genes between populations arises in evolution. Body sizes of mates were weakly correlated. In one year, the smallest females were paired non-randomly with the males of similar size, and in another year the largest males were paired with the largest females. An influence of parental morphology on the choice of mates, as expected from sexual imprinting theory, was found; the body size of mates was predicted by the body sizes of both parents, and especially strongly by the father's. These associations imply that the seeds of reproductive isolation between species are present within a single variable population. The implication was subject to a natural test: two exceptionally large birds of the study species, apparently immigrants, bred with each other, as did their offspring, and not with the members of the resident population. The intense inbreeding represents incipient speciation. It parallels a similar phenomenon when another species, the large ground finch, immigrated to Daphne and established a new population without interbreeding with the resident medium ground finches.

  14. Dietary carotenoids predict plumage coloration in wild house finches.

    PubMed Central

    Hill, Geoffrey E; Inouye, Caron Y; Montgomerie, Robert

    2002-01-01

    Carotenoid pigments are a widespread source of ornamental coloration in vertebrates and expression of carotenoid-based colour displays has been shown to serve as an important criterion in female mate choice in birds and fishes. Unlike other integumentary pigments, carotenoids cannot be synthesized; they must be ingested. Carotenoid-based coloration is condition-dependent and has been shown to be affected by both parasites and nutritional condition. A controversial hypothesis is that the expression of carotenoid-based coloration in wild vertebrates is also affected by the amount and types of carotenoid pigments that are ingested. We tested this carotenoid-limitation hypothesis by sampling the gut contents of moulting house finches and comparing the concentration of carotenoid pigments in their gut contents with the colour of growing feathers. We found a positive association: males that ingested food with a higher concentration of carotenoid pigments grew brighter ornamental plumage. We also compared the concentration of carotenoids in the gut contents of males from two subspecies of house finches with small and large patches of carotenoid-based coloration. Consistent with the hypothesis that carotenoid access drives the evolution of carotenoid-based colour displays, males from the population with limited ornamentation had much lower concentrations of carotenoids in their gut contents than males from the population with extensive ornamentation. These observations support the idea that carotenoid intake plays a part in determining the plumage brightness of male house finches. PMID:12061954

  15. The Cell Birth Marker BrdU Does Not Affect Recruitment of Subsequent Cell Divisions in the Adult Avian Brain

    PubMed Central

    Cattan, Anat

    2015-01-01

    BrdU is commonly used to quantify neurogenesis but also causes mutation and has mitogenic, transcriptional, and translational effects. In mammalian studies, attention had been given to its dosage, but in birds such examination was not conducted. Our previous study suggested that BrdU might affect subsequent cell divisions and neuronal recruitment in the brain. Furthermore, this effect seemed to increase with time from treatment. Accordingly, we examined whether BrdU might alter neurogenesis in the adult avian brain. We compared recruitment of [3H]-thymidine+ neurons in brains of zebra finches (Taeniopygia guttata) when no BrdU was involved and when BrdU was given 1 or 3 months prior to [3H]-thymidine. In nidopallium caudale, HVC, and hippocampus, no differences were found between groups in densities and percentages of [3H]-thymidine+ neurons. The number of silver grains per [3H]-thymidine+ neuronal nucleus and their distribution were similar across groups. Additionally, time did not affect the results. The results indicate that the commonly used dosage of BrdU in birds has no long-term effects on subsequent cell divisions and neuronal recruitment. This conclusion is also important in neuronal replacement experiments, where BrdU and another cell birth marker are given, with relatively long intervals between them. PMID:25759813

  16. Detection of bovine papillomavirus DNA in sarcoid-affected and healthy free-roaming zebra (Equus zebra) populations in South Africa.

    PubMed

    van Dyk, Enette; Oosthuizen, Marinda C; Bosman, Anna-Marie; Nel, Pierre J; Zimmerman, David; Venter, Estelle H

    2009-06-01

    The endangered Cape mountain zebra (Equus zebra zebra) is protected in small numbers in a few isolated populations in South African game parks. Since 1995, sarcoid lesions appeared in zebras in two of the parks. This study was undertaken to investigate if bovine papillomavirus (BPV) is associated with sarcoids in these zebras. A conventional PCR, targeting the E5 ORF of BPV, and subsequent RFLP analysis were initially used to demonstrate the presence of BPV-1 and -2 DNAs in zebra sarcoid tumours. A rapid, sensitive and reliable real-time PCR to detect and distinguish between BPV-1 and -2 infections in zebras was developed. With this assay it was demonstrated that BPV-1 and -2 DNA (either single or mixed infections) are present in sarcoid tumour, healthy skin and blood of sarcoid-affected and healthy zebras from sarcoid-affected parks as well as in the blood of zebras from parks where no sarcoid has been observed before.

  17. Invasion of the Zebra Mussels: A Mock Trial Activity

    ERIC Educational Resources Information Center

    Beck, Judy A.; Czerniak, Charlene M.

    2005-01-01

    In this activity, students learn about the important topic of invasive species, specifically Zebra Mussels. Students role-play different characters in a real-life situation: the trial of the Zebra Mussel for unlawful disruption of the Great Lakes ecosystem. Students will also learn about jurisprudential inquiry by examining the trial process. This…

  18. Comparative biology of zebra mussels in Europe and North America: an overview

    USGS Publications Warehouse

    Mackie, Gerald L.; Schloesser, Don W.

    1996-01-01

    SYNOPSIS. Since the discovery of the zebra mussel, Dreissena polymorpha, in the Great Lakes in 1988 comparisons have been made with mussel populations in Europe and the former Soviet Union. These comparisons include: Population dynamics, growth and mortality rates, ecological tolerances and requirements, dispersal rates and patterns, and ecological impacts. North American studies, mostly on the zebra mussel and a few on a second introduced species, the quagga mussel, Dreissena bugensis, have revealed some similarities and some differences. To date it appears that North American populations of zebra mussels are similar to European populations in their basic biological characteristics, population growth and mortality rates, and dispersal mechanisms and rates. Relative to European populations differences have been demonstrated for: (1) individual growth rates; (2) life spans; (3) calcium and pH tolerances and requirements; (4) potential distribution limits; and (5) population densities of veligers and adults. In addition, studies on the occurrence of the two dreissenid species in the Great Lakes are showing differences in their modes of life, depth distributions, and growth rates. As both species spread throughout North America, comparisons between species and waterbodies will enhance our ability to more effectively control these troublesome species.

  19. The zebra mussel, Dreissena polymorpha (Pallas, 1771), in North America: impact on raw water users

    USGS Publications Warehouse

    Griffiths, Ronald W.; Kovalak, William P.; Schloesser, Donald W.

    1989-01-01

    The zebra mussel, Dreissena polymorpha (Pallas), is a small mollusc native to the Black, Caspian, and Azov Seas that was discovered in Lake Erie of the Laurentian Great Lakes of North America in 1988. Its presence there raises immediate concerns for users of raw water because it can become abundant enough to obstruct the flow of water through pipes, hoses, screens, and condensers. Biofouling attributed to this mussel was observed at several power plants, water treatment plants, and food processing and industrial facilities along Lake Erie in 1989. Estimated densities at one power plant intake canal were as high as 700,000 per m2. In addition, large numbers were found in main steam condensors and in the service water system, threatening the water supply for cooling, fire protection, and dust suppression systems. Municipal water intakes along the Canadian and United States shorelines have also been impaired. In one southeast Michigan city, drinking water withdrawal from Lake Erie was reduced 45% by the mussel. Routine checks of raw water supplies for free-floating zebra mussel veligers are reommended to determine if reproducing adult populations are present in local water bodies. After an early alert, raw water intakes could be protected to alleviate damage from the biofouling zebra mussel.

  20. Linda Finch speaks to children during World Flight in New Orleans, La.

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Linda Finch, who re-created the flight of Amelia Earhardt's flight around the world 60 years ago, landed at New Orleans Lakefront Airport to speak to groups of inner-city school children during World Flight 1997. Stennis Space Center's Educator Resource Center played a role in the event by providing SSC-developed Geomap software to aid students in tracking Finch's flight.

  1. Improved axial resolution of FINCH fluorescence microscopy when combined with spinning disk confocal microscopy

    PubMed Central

    Siegel, Nisan; Brooker, Gary

    2014-01-01

    FINCH holographic fluorescence microscopy creates super-resolved images with enhanced depth of focus. Addition of a Nipkow disk real-time confocal image scanner is shown to reduce the FINCH depth of focus while improving transverse confocal resolution in a combined method called “CINCH”. PMID:25321701

  2. Hudson River Unionids and Zebra Mussels: The Beginning of the End or the End of the Beginning?

    NASA Astrophysics Data System (ADS)

    Strayer, D. L.; Malcom, H. M.

    2005-05-01

    The invasion of the Hudson River estuary by zebra mussels was followed by steep declines (77 to >99.7%) in populations of all species of native bivalves between 1992 and 1999. Body condition of all unionids, and growth and recruitment of young unionids also declined significantly. Declines in population size and body condition were correlated primarily with the filtration rate of the zebra mussel population, not with fouling of native bivalves by zebra mussels. Samples taken since 2000, however, have shown that populations of all 4 common native bivalves have stabilized or even recovered, although the zebra mussel population has not declined. The mechanisms underlying this apparent reversal of fortune are not clear: recruitment and growth of young mussels have showed limited recovery, but body condition of adults has not. We found no evidence that spatial refuges contributed to this reversal of population declines. Simple statistical models project now that native bivalves may persist at population densities about an order of magnitude below their pre-invasion densities.

  3. George Ingle Finch and the Mount Everest expedition of 1922: breaching the 8000-m barrier.

    PubMed

    Rodway, George W

    2007-01-01

    Alpinist and scientist George Ingle Finch was invited on the 1921 British Mount Everest Reconnaissance, but events conspired to keep him away from Everest until the 1922 British expedition to the mountain. Very little is known in the English-speaking world about the 1925 German language book Der Kampf um den Everest, written by Finch and covering the Everest attempts of the 1920s, as it was never published in English. Additionally, very little has been published from Finch's personal diaries of the 1922 Everest climb. The object of this work is to utilize translated sections of Der Kampf um den Everest and passages from Finch's 1922 Everest diaries to create some sense of George Finch's personal perspective of the 1922 Everest attempt. This historic climb was the first mountaineering expedition to breach the 8000-m barrier when two separate parties, one climbing with supplementary oxygen and the other without, established new terrestrial altitude records.

  4. Contrasting natural experiments confirm competition between House Finches and House Sparrows.

    PubMed

    Cooper, Caren B; Hochachka, Wesley M; Dhondt, André A

    2007-04-01

    After House Finches were introduced from the western to the eastern United States and rapidly increased in numbers, House Sparrows declined, leading to suggestions that the decline was caused by interspecific competition. However, other potential causes were not excluded. The rapid decline in House Finches following the emergence of a new disease (mycoplasmal conjunctivitis) caused by a novel strain of Mycoplasma gallisepticum (MG) in 1994 has provided a natural experiment and an opportunity to revisit the hypothesis that interspecific competition from House Finches drives population changes in House Sparrows. If true, the recent decline in House Finches should lead to an increase in House Sparrows. In this paper we test the hypothesis that House Sparrow and House Finch numbers in the northeastern United States vary inversely by examining data from three independent volunteer programs that monitor bird species' abundance and distribution (Christmas Bird Count, Project FeederWatch, and Breeding Bird Survey). In the first analysis we found that House Sparrow and House Finch numbers varied inversely during a time interval when House Finches were increasing and a time interval when House Finches were decreasing. In the second analysis, we found that the rates of geometric change in House Sparrow abundance (ln[HOSP(t+1)/HOSP(t)]) were negatively correlated with initial House Finch (HOFI(t)) and sparrow (HOSP(t)) abundances at individual sites, irrespective of the time period. Given that finch range expansion and subsequent declines in abundance are the result of two very different phenomena, it would be very unlikely for apparent competition or spurious correlations to cause the observed concomitant changes in House Sparrow abundance. We conclude that interspecific competition exists between these two species.

  5. Environmentally Safe Control of Zebra Mussel Fouling

    SciTech Connect

    Daniel Molloy

    2008-02-29

    The two primary objectives of this USDOE-NETL contract were successfully achieved during the project: (1) to accelerate research on the development of the bacterium Pseudomonas fluorescens strain CL145A (Pf-CL145A) as a biocontrol agent for zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis)--two invasive freshwater bivalve species that are infesting water pipes in power plants; and (2) to identify a private-sector company that would move forward to commercialize Pf-CL145A as a substitute for the current polluting use of biocide chemicals for control of these dreissenid mussels in power plant pipes.

  6. Zebra mussels enter the compost pile

    SciTech Connect

    Not Available

    1992-08-01

    Zebra mussels, introduced accidentally into the Great Lakes, are overpopulating at phenomenal rates, especially in Lake Erie, where they damage oyster beds, foster excessive algae growth and cling to boats. They also clog the intake pipes of city water systems and power generating plants. The expense of cleaning intake screens is considerable, since they have to be physically removed and cleaned. Then the mussels must be disposed of, costing some power plants as much as $50,000 a year to landfill, says Wayne Koser of the Michigan Department of Natural Resources.

  7. Zebra mussel infestation of unionid bivalves (Unionidae) in North America

    USGS Publications Warehouse

    Schloesser, Don W.; Nalepa, Thomas F.; Mackie, Gerald L.

    1996-01-01

    In 1989, zebra mussels received national attention in North America when they reached densities exceeding 750,000/m2 in a water withdrawal facility along the shore of western Lake Erie of the Laurentian Great Lakes. Although water withdrawal problems caused by zebra mussels have been of immediate concern, ecological impacts attributed to mussels are likely to be the more important long-term issue for surface waters in North America. To date, the epizoic colonization (i.e., infestation) of unionid bivalve mollusks by zebra mussels has caused the most direct and severe ecological impact. Infestation of and resulting impacts caused by zebra mussels on unionids in the Great Lakes began in 1988. By 1990, mortality of unionids was occurring at some locations; by 1991, extant populations of unionids in western Lake Erie were nearly extirpated; by 1992, unionid populations in the southern half of Lake St. Clair were extirpated; by 1993, unionids in widely separated geographic areas of the Great Lakes and the Mississippi River showed high mortality due to mussel infestation. All infested unionid species in the Great Lakes (23) have become infested and exhibited mortality within two to four years after heavy infestation began. Data indicate that mean zebra mussel densities >5,000–6,000/m2 and infestation intensities >100-200/unionid in the presence of heavy zebra mussel recruitment results in near total mortality of unionids. At present, all unionid species in rivers, streams, and akes that sympatrically occur with zebra mussels have been infested and, in many locations, negatively impacted by zebra mussels. We do not know the potential consequences of infestation on the 297 unionid species found in North America, but believe zebra mussels pose an immediate threat to the abundance and diversity of unionids.

  8. Studies on the parasites of zebras. IV. Cylicodontophorus reineckei n.sp. (Nematoda: Strongylidae) from the Burchell's zebra, Equus burchelli antiquorum H. Smith, 1841 and the mountain zebra, Equus zebra hartmannae Matschie, 1898.

    PubMed

    Scialdo-Krecek, R C; Malan, F S

    1984-12-01

    A new species of nematode, Cylicodontophorus reineckei, was collected from Burchell's zebra, Equus burchelli antiquorum H. Smith, 1841, in both the Etosha National and Kruger National Parks and from mountain zebra, Equus zebra hartmannae Matschie, 1898, in the Namib Naukluft Park in South West Africa/Namibia. These nematodes have an external leaf-crown with longer elements than those of the internal leaf-crown and a well-developed dorsal gutter. The very well-developed oesophageal funnel is both wider and deeper than the buccal capsule.

  9. Crayfish (Orconectes virilis) predation on zebra mussels (Dreissena polymorpha)

    USGS Publications Warehouse

    Love, Joy; Savino, Jacqueline F.

    1993-01-01

    In laboratory studies, we quantified predation rates and handling time of crayfish (Orconectes virilis) on zebra mussels (Dreissena polymorpha) and rainbow trout (Oncorhhynchus mykiss) eggs. In single prey species tests, crayfish ate zebra mussels at similar rates as they ate rainbow trout eggs. When both prey were present, crayfish preferred rainbow trout eggs. Handling time of mussels was about twice that of rainbow trout eggs, and energetic content of mussels was lower. Therefore, net benefit for foraging on rainbow trout eggs was about three times that of foraging on zebra mussels.

  10. Radio diagnostic of loop oscillations with wavy zebra patterns

    NASA Astrophysics Data System (ADS)

    Zlotnik, E. Ya.; Zaitsev, V. V.; Aurass, H.

    The possible reasons for the wave-like frequency drift of zebra stripes in solar radio emission are analysed. For the event of October 25, 1994 recorded by the radio spectrograph of the Astrophysical Institute Potsdam (AIP) it is shown that if the zebra pattern is due to the effect of the double plasma resonance in an inhomogeneous coronal loop, then the oscillating change of zebra stripes frequencies may be associated with fast magneto-sonic (FMS) oscillations of the magnetic flux tube. Such a conclusion is based on the agreement of the theoretically predicted FMS-mode period and its dependence on the harmonic number with the observed values.

  11. Condition index monitoring supports conservation priorities for the protection of threatened grass-finch populations.

    PubMed

    Maute, Kimberly; French, Kristine; Legge, Sarah; Astheimer, Lee; Garnett, Stephen

    2015-01-01

    Conservation agencies are often faced with the difficult task of prioritizing what recovery actions receive support. With the number of species under threat of decline growing globally, research that informs conservation priorities is greatly needed. The relative vulnerability of cryptic or nomadic species is often uncertain, because populations are difficult to monitor and local populations often seem stable in the short term. This uncertainty can lead to inaction when populations are in need of protection. We tested the feasibility of using differences in condition indices as an indication of population vulnerability to decline for related threatened Australian finch sub-species. The Gouldian finch represents a relatively well-studied endangered species, which has a seasonal and site-specific pattern of condition index variation that differs from the closely related non-declining long-tailed finch. We used Gouldian and long-tailed finch condition variation as a model to compare with lesser studied, threatened star and black-throated finches. We compared body condition (fat and muscle scores), haematocrit and stress levels (corticosterone) among populations, seasons and years to determine whether lesser studied finch populations matched the model of an endangered species or a non-declining species. While vulnerable finch populations often had lower muscle and higher fat and corticosterone concentrations during moult (seasonal pattern similar to Gouldian finches), haematocrit values did not differ among populations in a predictable way. Star and black-throated finch populations, which were predicted to be vulnerable to decline, showed evidence of poor condition during moult, supporting their status as vulnerable. Our findings highlight how measures of condition can provide insight into the relative vulnerability of animal and plant populations to decline and will allow the prioritization of efforts towards the populations most likely to be in jeopardy of extinction

  12. Invasive parasites, habitat change and heavy rainfall reduce breeding success in Darwin's finches.

    PubMed

    Cimadom, Arno; Ulloa, Angel; Meidl, Patrick; Zöttl, Markus; Zöttl, Elisabet; Fessl, Birgit; Nemeth, Erwin; Dvorak, Michael; Cunninghame, Francesca; Tebbich, Sabine

    2014-01-01

    Invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. On the Galápagos Islands, the invasive parasitic fly Philornis downsi poses a major threat to the endemic avifauna. Here, we investigated the influence of this parasite on the breeding success of two Darwin's finch species, the warbler finch (Certhidea olivacea) and the sympatric small tree finch (Camarhynchus parvulus), on Santa Cruz Island in 2010 and 2012. While the population of the small tree finch appeared to be stable, the warbler finch has experienced a dramatic decline in population size on Santa Cruz Island since 1997. We aimed to identify whether warbler finches are particularly vulnerable during different stages of the breeding cycle. Contrary to our prediction, breeding success was lower in the small tree finch than in the warbler finch. In both species P. downsi had a strong negative impact on breeding success and our data suggest that heavy rain events also lowered the fledging success. On the one hand parents might be less efficient in compensating their chicks' energy loss due to parasitism as they might be less efficient in foraging on days of heavy rain. On the other hand, intense rainfalls might lead to increased humidity and more rapid cooling of the nests. In the case of the warbler finch we found that the control of invasive plant species with herbicides had a significant additive negative impact on the breeding success. It is very likely that the availability of insects (i.e. food abundance)is lower in such controlled areas, as herbicide usage led to the removal of the entire understory. Predation seems to be a minor factor in brood loss.

  13. Condition index monitoring supports conservation priorities for the protection of threatened grass-finch populations.

    PubMed

    Maute, Kimberly; French, Kristine; Legge, Sarah; Astheimer, Lee; Garnett, Stephen

    2015-01-01

    Conservation agencies are often faced with the difficult task of prioritizing what recovery actions receive support. With the number of species under threat of decline growing globally, research that informs conservation priorities is greatly needed. The relative vulnerability of cryptic or nomadic species is often uncertain, because populations are difficult to monitor and local populations often seem stable in the short term. This uncertainty can lead to inaction when populations are in need of protection. We tested the feasibility of using differences in condition indices as an indication of population vulnerability to decline for related threatened Australian finch sub-species. The Gouldian finch represents a relatively well-studied endangered species, which has a seasonal and site-specific pattern of condition index variation that differs from the closely related non-declining long-tailed finch. We used Gouldian and long-tailed finch condition variation as a model to compare with lesser studied, threatened star and black-throated finches. We compared body condition (fat and muscle scores), haematocrit and stress levels (corticosterone) among populations, seasons and years to determine whether lesser studied finch populations matched the model of an endangered species or a non-declining species. While vulnerable finch populations often had lower muscle and higher fat and corticosterone concentrations during moult (seasonal pattern similar to Gouldian finches), haematocrit values did not differ among populations in a predictable way. Star and black-throated finch populations, which were predicted to be vulnerable to decline, showed evidence of poor condition during moult, supporting their status as vulnerable. Our findings highlight how measures of condition can provide insight into the relative vulnerability of animal and plant populations to decline and will allow the prioritization of efforts towards the populations most likely to be in jeopardy of extinction.

  14. Galápagos mockingbirds tolerate introduced parasites that affect Darwin's finches.

    PubMed

    Knutie, Sarah A; Owen, Jeb P; McNew, Sabrina M; Bartlow, Andrew W; Arriero, Elena; Herman, Jordan M; DiBlasi, Emily; Thompson, Michael; Koop, Jennifer A H; Clayton, Dale H

    2016-04-01

    Introduced parasites threaten native host species that lack effective defenses. Such parasites increase the risk of extinction, particularly in small host populations like those on islands. If some host species are tolerant to introduced parasites, this could amplify the risk of the parasite to vulnerable host species. Recently, the introduced parasitic nest fly Philornis downsi has been implicated in the decline of Darwin's finch populations in the Galápagos Islands. In some years, 100% of finch nests fail due to P. downsi; however, other common host species nesting near Darwin's finches, such as the endemic Galápagos mockingbird (Mimus parvulus), appear to be less affected by P. downsi. We compared effects of P. downsi on mockingbirds and medium ground finches (Geospiza fortis) on Santa Cruz Island in the Galápagos. We experimentally manipulated the abundance of P. downsi in nests of mockingbirds and finches to measure the direct effect of the parasite on the reproductive success of each species of host. We also compared immunological and behavioral responses by each species of host to the fly. Although nests of the two host species had similar parasite densities, flies decreased the fitness of finches but not mockingbirds. Neither host species had a significant antibody-mediated immune response to P. downsi. Moreover, finches showed no significant increase in begging, parental provisioning, or plasma glucose levels in response to the flies. In contrast, parasitized mockingbird nestlings begged more than nonparasitized mockingbird nestlings. Greater begging was correlated with increased parental provisioning behavior, which appeared to compensate for parasite damage. The results of our study suggest that finches are negatively affected by P. downsi because they do not have such behavioral mechanisms for energy compensation. In contrast, mockingbirds are capable of compensation, making them tolerant hosts, and a possible indirect threat to Darwin's finches.

  15. Invasive Parasites, Habitat Change and Heavy Rainfall Reduce Breeding Success in Darwin's Finches

    PubMed Central

    Cimadom, Arno; Ulloa, Angel; Meidl, Patrick; Zöttl, Markus; Zöttl, Elisabet; Fessl, Birgit; Nemeth, Erwin; Dvorak, Michael; Cunninghame, Francesca; Tebbich, Sabine

    2014-01-01

    Invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. On the Galápagos Islands, the invasive parasitic fly Philornis downsi poses a major threat to the endemic avifauna. Here, we investigated the influence of this parasite on the breeding success of two Darwin's finch species, the warbler finch (Certhidea olivacea) and the sympatric small tree finch (Camarhynchus parvulus), on Santa Cruz Island in 2010 and 2012. While the population of the small tree finch appeared to be stable, the warbler finch has experienced a dramatic decline in population size on Santa Cruz Island since 1997. We aimed to identify whether warbler finches are particularly vulnerable during different stages of the breeding cycle. Contrary to our prediction, breeding success was lower in the small tree finch than in the warbler finch. In both species P. downsi had a strong negative impact on breeding success and our data suggest that heavy rain events also lowered the fledging success. On the one hand parents might be less efficient in compensating their chicks' energy loss due to parasitism as they might be less efficient in foraging on days of heavy rain. On the other hand, intense rainfalls might lead to increased humidity and more rapid cooling of the nests. In the case of the warbler finch we found that the control of invasive plant species with herbicides had a significant additive negative impact on the breeding success. It is very likely that the availability of insects (i.e. food abundance)is lower in such controlled areas, as herbicide usage led to the removal of the entire understory. Predation seems to be a minor factor in brood loss. PMID:25248092

  16. Condition index monitoring supports conservation priorities for the protection of threatened grass-finch populations

    PubMed Central

    Maute, Kimberly; French, Kristine; Legge, Sarah; Astheimer, Lee; Garnett, Stephen

    2015-01-01

    Conservation agencies are often faced with the difficult task of prioritizing what recovery actions receive support. With the number of species under threat of decline growing globally, research that informs conservation priorities is greatly needed. The relative vulnerability of cryptic or nomadic species is often uncertain, because populations are difficult to monitor and local populations often seem stable in the short term. This uncertainty can lead to inaction when populations are in need of protection. We tested the feasibility of using differences in condition indices as an indication of population vulnerability to decline for related threatened Australian finch sub-species. The Gouldian finch represents a relatively well-studied endangered species, which has a seasonal and site-specific pattern of condition index variation that differs from the closely related non-declining long-tailed finch. We used Gouldian and long-tailed finch condition variation as a model to compare with lesser studied, threatened star and black-throated finches. We compared body condition (fat and muscle scores), haematocrit and stress levels (corticosterone) among populations, seasons and years to determine whether lesser studied finch populations matched the model of an endangered species or a non-declining species. While vulnerable finch populations often had lower muscle and higher fat and corticosterone concentrations during moult (seasonal pattern similar to Gouldian finches), haematocrit values did not differ among populations in a predictable way. Star and black-throated finch populations, which were predicted to be vulnerable to decline, showed evidence of poor condition during moult, supporting their status as vulnerable. Our findings highlight how measures of condition can provide insight into the relative vulnerability of animal and plant populations to decline and will allow the prioritization of efforts towards the populations most likely to be in jeopardy of extinction

  17. Galápagos mockingbirds tolerate introduced parasites that affect Darwin's finches.

    PubMed

    Knutie, Sarah A; Owen, Jeb P; McNew, Sabrina M; Bartlow, Andrew W; Arriero, Elena; Herman, Jordan M; DiBlasi, Emily; Thompson, Michael; Koop, Jennifer A H; Clayton, Dale H

    2016-04-01

    Introduced parasites threaten native host species that lack effective defenses. Such parasites increase the risk of extinction, particularly in small host populations like those on islands. If some host species are tolerant to introduced parasites, this could amplify the risk of the parasite to vulnerable host species. Recently, the introduced parasitic nest fly Philornis downsi has been implicated in the decline of Darwin's finch populations in the Galápagos Islands. In some years, 100% of finch nests fail due to P. downsi; however, other common host species nesting near Darwin's finches, such as the endemic Galápagos mockingbird (Mimus parvulus), appear to be less affected by P. downsi. We compared effects of P. downsi on mockingbirds and medium ground finches (Geospiza fortis) on Santa Cruz Island in the Galápagos. We experimentally manipulated the abundance of P. downsi in nests of mockingbirds and finches to measure the direct effect of the parasite on the reproductive success of each species of host. We also compared immunological and behavioral responses by each species of host to the fly. Although nests of the two host species had similar parasite densities, flies decreased the fitness of finches but not mockingbirds. Neither host species had a significant antibody-mediated immune response to P. downsi. Moreover, finches showed no significant increase in begging, parental provisioning, or plasma glucose levels in response to the flies. In contrast, parasitized mockingbird nestlings begged more than nonparasitized mockingbird nestlings. Greater begging was correlated with increased parental provisioning behavior, which appeared to compensate for parasite damage. The results of our study suggest that finches are negatively affected by P. downsi because they do not have such behavioral mechanisms for energy compensation. In contrast, mockingbirds are capable of compensation, making them tolerant hosts, and a possible indirect threat to Darwin's finches

  18. Extra-pair paternity in the long-tailed finch Poephila acuticauda

    PubMed Central

    van Rooij, Erica P.; Rollins, Lee A.; Holleley, Clare E.

    2016-01-01

    Although the majority of passerine birds are socially monogamous, true genetic monogamy is rare, with extra-pair paternity (EPP) occurring in almost 90% of surveyed socially monogamous species. We present the first molecular data on the genetic breeding system of the long-tailed finch, Poephila acuticauda, a grass finch endemic to the tropical northern savannah of Australia. Although the species forms socially monogamous pair bonds during the breeding season, we found that extra-pair males sired 12.8% of 391 offspring, in 25.7% of 101 broods. Our findings provide only the second estimate of extra-pair paternity in the estrildid finch family. PMID:26788429

  19. Exploring vocal recovery after cranial nerve injury in Bengalese finches.

    PubMed

    Urbano, Catherine M; Peterson, Jennifer R; Cooper, Brenton G

    2013-02-01

    Songbirds and humans use auditory feedback to acquire and maintain their vocalizations. The Bengalese finch (Lonchura striata domestica) is a songbird species that rapidly modifies its vocal output to adhere to an internal song memory. In this species, the left side of the bipartite vocal organ is specialized for producing louder, higher frequencies (≥2.2kHz) and denervation of the left vocal muscles eliminates these notes. Thus, the return of higher frequency notes after cranial nerve injury can be used as a measure of vocal recovery. Either the left or right side of the syrinx was denervated by resection of the tracheosyringeal portion of the hypoglossal nerve. Histologic analyses of syringeal muscle tissue showed significant muscle atrophy in the denervated side. After left nerve resection, songs were mainly composed of lower frequency syllables, but three out of five birds recovered higher frequency syllables. Right nerve resection minimally affected phonology, but it did change song syntax; syllable sequence became abnormally stereotyped after right nerve resection. Therefore, damage to the neuromuscular control of sound production resulted in reduced motor variability, and Bengalese finches are a potential model for functional vocal recovery following cranial nerve injury.

  20. The secondary contact phase of allopatric speciation in Darwin's finches

    PubMed Central

    Grant, Peter R.; Grant, B. Rosemary

    2009-01-01

    Speciation, the process by which two species form from one, involves the development of reproductive isolation of two divergent lineages. Here, we report the establishment and persistence of a reproductively isolated population of Darwin's finches on the small Galápagos Island of Daphne Major in the secondary contact phase of speciation. In 1981, an immigrant medium ground finch (Geospiza fortis) arrived on the island. It was unusually large, especially in beak width, sang an unusual song, and carried some Geospiza scandens alleles. We followed the fate of this individual and its descendants for seven generations over a period of 28 years. In the fourth generation, after a severe drought, the lineage was reduced to a single brother and sister, who bred with each other. From then on this lineage, inheriting unusual song, morphology, and a uniquely homozygous marker allele, was reproductively isolated, because their own descendants bred with each other and with no other member of the resident G. fortis population. These observations agree with some expectations of an ecological theory of speciation in that a barrier to interbreeding arises as a correlated effect of adaptive divergence in morphology. However, the important, culturally transmitted, song component of the barrier appears to have arisen by chance through an initial imperfect copying of local song by the immigrant. The study reveals additional stochastic elements of speciation, in which divergence is initiated in allopatry; immigration to a new area of a single male hybrid and initial breeding with a rare hybrid female. PMID:19918081

  1. The 1.0-4.5 GHz Zebras in the June 6, 2000 Flare

    NASA Astrophysics Data System (ADS)

    Sawant, H. S.; Karlický, M.; Fernandes, F. C. R.; Cecatto, J. R.

    2002-01-01

    For the first time we are reporting harmonically related zebra structures above 1000 MHz, having ratio of 1:2. Zebra structures show up to 8 zebra lines. In individual zebra patterns the frequency ratio of the neighbouring zebra lines are less than 1.03 and these ratios decrease with the frequency decrease. The zebra patterns are analyzed and interpreted assuming double plasma resonance instability as the cause for their generation. The longitudinal upper hybrid waves are excited at positions of cyclotron resonances and then transformed into electromagnetic ones. Using this model the magnetic field strengths in the flaring loops are estimated in the range of 110-230 G.

  2. Zebra mussel-directed foodchain transfer of environmental contaminants

    SciTech Connect

    Fisher, S.W.; Bruner, K.A.; Landrum, P.F.

    1994-12-31

    Zebra mussel densities in some near-shore areas of Lake Erie exceed 500,000 individuals m{sup 3}. Because of their large biomass, the zebra mussels can collectively filter the entire volume of Lake Erie`s western basin in approximately 7 days. In so doing, the mussels remove a significant fraction of suspended particles, including algae and sediment. If those particles are contaminated with PCBs, the mussels could potentially redirect contaminant cycling in Lake Erie. Their data show that contaminated particles are a significant source of contaminants for the zebra mussel with sediment being more significant source than algae. When particles are the source of contamination for the zebra mussel, significant foodchain contamination may result from direct consumption of contaminated mussels or via an indirect route in which unassimilated contaminants are shunted into zebra mussel feces and the latter are consumed by benthic invertebrates. Trophic transfer of PCBs from zebra mussel feces to gammarids was measured. Importantly, biomagnification of some PCB congeners occurred during foodchain transfer from particles to mussels to feces such that the indirect route of transfer through ingestion of contaminated feces is more significant ecologically. Implications for Lake Erie foodchains will be discussed.

  3. Full genome sequences of zebra-borne equine herpesvirus type 1 isolated from zebra, onager and Thomson's gazelle.

    PubMed

    Guo, Xiaoqin; Izume, Satoko; Okada, Ayaka; Ohya, Kenji; Kimura, Takashi; Fukushi, Hideto

    2014-09-01

    A strain of equine herpesvirus type 1 (EHV-1) was isolated from zebra. This strain, called "zebra-borne EHV-1", was also isolated from an onager and a gazelle in zoological gardens in U.S.A. The full genome sequences of the 3 strains were determined. They shared 99% identities with each other, while they shared 98% and 95% identities with the horse derived EHV-1 and equine herpesvirus type 9, respectively. Sequence data indicated that the EHV-1 isolated from a polar bear in Germany is one of the zebra-borne EHV-1 and not a recombinant virus. These results indicated that zebra-borne EHV-1 is a subtype of EHV-1. PMID:24920546

  4. Steam treatment of zebra mussels. Final report

    SciTech Connect

    Mussalli, Y.; Collins, F.

    1995-12-01

    Steam injection into intake bays is a nonchemical method to control zebra mussels. This technique was demonstrated at Dairyland Power Cooperative`s J.R Madgett Station located in Alma, Wisconsin. The J.P. Madgett Station has two water intakes with capacities of approximately 295,000 gallons and 265,000 gallons each. Each intake can be isolated permitting either full or reduced generation depending on river temperature conditions. In addition to the intake bays, the outside fire protection loop and hydrants were also treated with the hot water from one of the bays. This report describes the process design, piping and steam eductor configurations, portable industrial boiler sizing and description, and thermocouples to monitor the water temperature in the intake bay. The mollusk mortality, monitoring, and treatment results are also included.

  5. Descriptive study of an outbreak of equine sarcoid in a population of Cape mountain zebra (Equus zebra zebra) in the Gariep Nature Reserve.

    PubMed

    Nel, P J; Bertschinger, H; Williams, J; Thompson, P N

    2006-12-01

    An outbreak of equine sarcoid occurred in a population of Cape mountain zebra (Equus zebra zebra) at the Gariep Nature Reserve located in the southern Free State Province of South Africa in 1996. The course of the outbreak during 1996 to 2003 is described. During this period the average population size was 69 animals. Initially (1996) all affected animals were removed from the population. New cases continued to manifest and the incidence varied between 4.6% and 17.6%. Prevalence reached 24.7% in 2002. No sexual predilection was noticed in the 39 recorded cases. Of the affected individuals, 64% had a single lesion and no animal had more than 4 lesions. In males, the majority of lesions occurred in the inguinal area (55.17%), whereas in females they mostly occurred on the head and neck (41.38%). Lesions can increase 260% in size annually and may impede movement.

  6. USGS Zebra Mussel Monitoring Program for north Texas

    USGS Publications Warehouse

    Churchill, Christopher J.; Baldys, Stanley

    2012-01-01

    The U.S. Geological Survey (USGS) Zebra Mussel Monitoring Program for north Texas provides early detection and monitoring of zebra mussels (Dreissena polymorpha) by using a holistic suite of detection methods. The program is designed to assess zebra mussel occurrence, distribution, and densities in north Texas waters by using four approaches: (1) SCUBA diving, (2) water-sample collection with plankton tow nets (followed by laboratory analyses), (3) artificial substrates, and (4) water-quality sampling. Data collected during this type of monitoring can assist rapid response efforts and can be used to quantify the economic and ecological effects of zebra mussels in the north Texas area. Monitoring under this program began in April 2010. The presence of large zebra mussel populations often causes undesirable economic and ecological effects, including damage to water-processing infrastructure and hydroelectric powerplants (with an estimated 10-year cost of $3.1 billion), displacement of native mussels, increases in concentrations of certain species of cyanobacteria, and increases in concentrations of geosmin (an organic compound that results in taste and odor issues in water). Since no large-scale, environmentally safe eradication method has been developed for zebra mussels, it is difficult to remove established populations. Broad physicochemical adaptability, prolific reproductive capacity, and rapid dispersal methods have enabled zebra mussels, within a period of about 20 years, to establish populations under differing environmental conditions across much of the eastern part of the United States. In Texas, the presence of zebra mussels was first confirmed in April 2009 in Lake Texoma in the Red River Basin along the Texas-Oklahoma border. They were most likely introduced into Lake Texoma through overland transport from an infested water body. Since then, the presence of zebra mussels has been reported in both the Red River and Washita River arms of Lake Texoma, in

  7. The evolutionary history of Darwin's finches: speciation, gene flow, and introgression in a fragmented landscape.

    PubMed

    Farrington, Heather L; Lawson, Lucinda P; Clark, Courtney M; Petren, Kenneth

    2014-10-01

    Many classic examples of adaptive radiations take place within fragmented systems such as islands or mountains, but the roles of mosaic landscapes and variable gene flow in facilitating species diversification is poorly understood. Here we combine phylogenetic and landscape genetic approaches to understand diversification in Darwin's finches, a model adaptive radiation. We combined sequence data from 14 nuclear introns, mitochondrial markers, and microsatellite variation from 51 populations of all 15 recognized species. Phylogenetic species-trees recovered seven major finch clades: ground, tree, vegetarian, Cocos Island, grey and green warbler finches, and a distinct clade of sharp-beaked ground finches (Geospiza cf. difficilis) basal to all ground and tree finches. The ground and tree finch clades lack species-level phylogenetic structure. Interisland gene flow and interspecies introgression vary geographically in predictable ways. First, several species exhibit concordant patterns of population divergence across the channel separating the Galápagos platform islands from the separate volcanic province of northern islands. Second, peripheral islands have more admixed populations while central islands maintain more distinct species boundaries. This landscape perspective highlights a likely role for isolation of peripheral populations in initial divergence, and demonstrates that peripheral populations may maintain genetic diversity through outbreeding during the initial stages of speciation.

  8. Examination of the potential of chlorine dioxide for use in zebra mussel veliger control

    SciTech Connect

    Rusznak, L.; Smolik, N.; Hale, L.; Freymark, S.

    1995-06-01

    Dreissena polymorpha (zebra mussel) veligers were treated with various concentrations of chlorine dioxide and exposed at several time intervals to determine the effectiveness of this oxidant as a veliger control agent. The direction of this testing was based on previous studies which determined the effectiveness of chlorine dioxide as a molluscicide for adult zebra mussel control. Zebra mussel veligers were collected from the Niagara River shoreline at an untreated site and tested using filtered river water from the same source. All testing was conducted on site at an industrial plant in order to insure the integrity of veligers collected for this study. The plankton wheel method was used to examine the effects of chlorine dioxide. This methodology involves intense microscopic examination of the test organism prior to and after chemical exposure todeterminen molluscicidal efficacy. Veliger mortality was determined based on observations of veliger movement. Typical criteria for the determination of mortality was expanded to include four categories; veliger actively swimming, internal musculature movement, no internal musculature movement observed, however not necessarily indicating a mortality and obviously a mortality. The treatment levels ranged from 0.75 ppm - 2.0 ppm which are considered to simulate treatment levels in actual applications. Mortality levels ranged on average from 16%-42% based on 30 minute or 60 minute exposure times. The determination exposure time was based on water flow time intervals in actural applications. Sodium hypochlorite was also evaluated in order to compare the effectiveness of chlorine dioxide against this known veliger control agent. Testing resulted in chlorine dioxide providing significantly better veliger control than sodium hypochlorite under similar conditions.

  9. Copper and copper-nickel alloys as zebra mussel antifoulants

    SciTech Connect

    Dormon, J.M.; Cottrell, C.M.; Allen, D.G.; Ackerman, J.D.; Spelt, J.K.

    1996-04-01

    Copper has been used in the marine environment for decades as cladding on ships and pipes to prevent biofouling by marine mussels (Mytilus edulis L.). This motivated the present investigation into the possibility of using copper to prevent biofouling in freshwater by both zebra mussels and quagga mussels (Dreissena polymorpha and D. bugensis collectively referred to as zebra mussels). Copper and copper alloy sheet proved to be highly effective in preventing biofouling by zebra mussels over a three-year period. Further studies were conducted with copper and copper-nickel mesh (lattice of expanded metal) and screen (woven wire with a smaller hole size), which reduced the amount of copper used. Copper screen was also found to be strongly biofouling-resistant with respect to zebra mussels, while copper mesh reduced zebra mussel biofouling in comparison to controls, but did not prevent it entirely. Preliminary investigations into the mechanism of copper antifouling, using galvanic couples, indicated that the release of copper ions from the surface of the exposed metal into the surrounding water is directly or indirectly responsible for the biofouling resistance of copper.

  10. Chemical regulation of spawning in the zebra mussel (Dreissena polymorpha)

    USGS Publications Warehouse

    Ram, Jeffrey L.; Nichols, S. Jerrine; Nalepa, Thomas F.; Schloesser, Donald W.

    1992-01-01

    Previous literature suggests that spawning in bivalves is chemically regulated, both by environmental chemical cues and by internal chemical mediators. In a model proposed for zebra mussels, chemicals from phytoplankton initially trigger spawning, and chemicals associated with gametes provide further stimulus for spawning. The response to environmental chemicals is internally mediated by a pathway utilizing serotonin (5-hydroxytryptamine, a neurotransmitter), which acts directly on both male and female gonads. The role of serotonin and most other aspects of the model have been tested only on bivalves other than zebra mussels. The effect of serotonin on zebra mussel spawning was tested. Serotonin (10-5 and 10-3 M) injected into ripe males induced spawning, but injection of serotonin into females did not. Gametes were not released by 10-6 serotonin; in most cases, serotonin injection did not release gametes from immature recipients. Serotonin injection provides a reliable means for identifying ripe male zebra mussels and for obtaining zebra mussel sperm without the need for dissection.

  11. Identification of larvae: The zebra mussel (Dreissena polymorpha), quagga mussel (Dreissena rosteriformis bugensis), and Asian clam (Corbicula fluminea)

    USGS Publications Warehouse

    Nichols, S. Jerrine; Black, M.G.

    1994-01-01

    There are presently four freshwater bivalves in the United States that produce larvae or veligers commonly found in the water column: two forms of Asian clams and two species of dreissenids. Portions of the geographic range of three of these bivalves, one species of Asian clam (Corbicula fluminea), zebra mussels (Dreissena polymorpha), and quagga mussels (Dreissena rosteriformis bugensis), overlap, causing problems with larval identification. To determine which characteristics can be used to separate larval forms, adult Asian clams, quaggas, and zebra mussels were brought into the laboratory and induced to spawn, and the resulting larvae were reared. Hybrids between quaggas and zebra mussels were also produced, but not reared to maturity. Characteristics allowing for the most rapid and accurate separation of larvae were hinge length, shell length/height, shell shape, shell size, and the presence or absence of a foot and velum. These characteristics were observed in laboratory-reared larvae of known parentage and field-caught larvae of unknown parentage. In most cases, larvae of the Asian clam can be readily separated from those produced by either type of dreissenid on the basis of shell size and presence of a foot. Separating the gametes and embryos of the two types of dreissenids is not possible, but after shell formation, most of the larval stages can be distinguished. Hinge length, shell length/height, and the similarity in size of the shell valves can be used to separate straight-hinged, umbonal, pediveliger, and plantigrade larvae. Quagga × zebra mussel hybrids show characteristics of both parents and are difficult to identify.

  12. Proceedings: Third International Zebra Mussel Conference, 1993

    SciTech Connect

    Tsou, J.L.; Mussalli, Y.G.

    1993-06-01

    This Third International Conference on Zebra Mussels was held on February 23--26, 1993 in Toronto, Ontario, Canada. The Conference was sponsored by American Water Works Association Research Foundation, Electric Power Research Institute, Environment Canada - Fisheries and Oceans, Great Lakes Seal Grant Network, Ontario Hydro, the Ontario Ministry of the Environment, and Ontario Ministry of Natural Resources to bring together representatives of utilities, manufacturers, researchers, and consultants. There were 105 papers presented in 16 sessions over 4 days, typically with 2 sessions running concurrently. These sessions were devoted to the following general topics: General Information, Biological and Ecological Considerations, Chemical Treatments, and Non-Chemical Treatments. A panel discussion devoted to the same topics was conducted on the second day, two concurrent special meetings (Workshop on Application of Electric Power Technology for Biofouling and Research Protocol Panel Meeting) were held on the third day, and a poster session containing 56 poster papers was held on the fourth day. Approximately 700 people attended this conference. This report contains selected technical papers from the formal presentations and the poster session. Of these 49 selected papers, there are 9 papers related to general information, 8 papers related to biological and ecological considerations, 20 papers related to chemical treatments, and 12 papers related to nonchemical treatments. Individual papers have been cataloged separately.

  13. Aryl hydrocarbon receptor activation impairs extracellular matrix remodeling during zebra fish fin regeneration.

    PubMed

    Andreasen, Eric A; Mathew, Lijoy K; Löhr, Christiane V; Hasson, Rachelle; Tanguay, Robert L

    2007-01-01

    Adult zebra fish completely regenerate their caudal (tail) fin following partial amputation. Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibits this regenerative process. Proper regulation of transcription, innervation, vascularization, and extracellular matrix (ECM) composition is essential for complete fin regeneration. Previous microarray studies suggest that genes involved in ECM regulation are misexpressed following activation of the aryl hydrocarbon receptor. To investigate whether TCDD blocks regeneration by impairing ECM remodeling, male zebra fish were i.p. injected with 50 ng/g TCDD or vehicle, and caudal fins were amputated. By 3 days postamputation (dpa), the vascular network in the regenerating fin of TCDD-exposed fish was disorganized compared to vehicle-exposed animals. Furthermore, immunohistochemical staining revealed that axonal outgrowth was impacted by TCDD as early as 3 dpa. Histological analysis demonstrated that TCDD exposure leads to an accumulation of collagen at the end of the fin ray just distal to the amputation site by 3 dpa. Mature lepidotrichial-forming cells (fin ray-forming cells) were not observed in the fins of TCDD-treated fish. The capacity to metabolize ECM was also altered by TCDD exposure. Quantitative real-time PCR studies revealed that the aryl hydrocarbon pathway is active and that matrix-remodeling genes are expressed in the regenerate following TCDD exposure.

  14. Observation of harmonically related solar radio zebra patterns in the 1-4 GHz frequency range

    NASA Astrophysics Data System (ADS)

    Sawant, H. S.; Karlický, M.; Fernandes, F. C. R.; Cecatto, J. R.

    2002-12-01

    A unique case of two zebra patterns related harmonically with ratio of ~ 1:2 was observed by distant radio telescopes at São José dos Campos and Ondřejov Observatories. Accompanied zebras show that the ratio of frequencies of the neighboring zebra lines is in the range of 1.009-1.037. There is a tendency of a decrease of this ratio with decreasing frequency within the specific zebra pattern. Both facts speak in favour of plasma emission models for the zebra pattern fine structure in radio burst continua.

  15. Quagga and zebra mussels: biology, impacts, and control

    USGS Publications Warehouse

    Nalepa, Thomas F.; Schloesser, Don W.; Nalepa, Thomas F.; Schloesser, Don W.

    2013-01-01

    Quagga and Zebra Mussels: Biology, Impacts, and Control, Second Edition provides a broad view of the zebra/quagga mussel issue, offering a historic perspective and up-to-date information on mussel research. Comprising 48 chapters, this second edition includes reviews of mussel morphology, physiology, and behavior. It details mussel distribution and spread in Europe and across North America, and examines policy and regulatory responses, management strategies, and mitigation efforts. In addition, this book provides extensive coverage of the impact of invasive mussel species on freshwater ecosystems, including effects on water clarity, phytoplankton, water quality, food web changes, and consequences to other aquatic fauna. It also reviews and offers new insights on how zebra and quagga mussels respond and adapt to varying environmental conditions. This new edition includes seven video clips that complement chapter text and, through visual documentation, provide a greater understanding of mussel behavior and distribution.

  16. Regulation of stem cells in the zebra fish hematopoietic system.

    PubMed

    Huang, H-T; Zon, L I

    2008-01-01

    Hematopoietic stem cells (HSCs) have been used extensively as a model for stem cell biology. Stem cells share the ability to self-renew and differentiate into multiple cell types, making them ideal candidates for tissue regeneration or replacement therapies. Current applications of stem cell technology are limited by our knowledge of the molecular mechanisms that control their proliferation and differentiation, and various model organisms have been used to fill these gaps. This chapter focuses on the contributions of the zebra fish model to our understanding of stem cell regulation within the hematopoietic system. Studies in zebra fish have been valuable for identifying new genetic and signaling factors that affect HSC formation and development with important implications for humans, and new advances in the zebra fish toolbox will allow other aspects of HSC behavior to be investigated as well, including migration, homing, and engraftment.

  17. IMPACT OF WATER PH ON ZEBRA MUSSEL MORTALITY

    SciTech Connect

    Daniel P. Molloy

    2002-10-15

    The experiments conducted this past quarter have suggested that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels throughout the entire range of pH values tested (7.2 to 8.6). Highest mortality was achieved at pH values characteristic of preferred zebra mussel waterbodies, i.e., hard waters with a range of 7.8 to 8.6. In all water types tested, however, ranging from very soft to very hard, considerable mussel kill was achieved (83 to 99% mean mortality), suggesting that regardless of the pH or hardness of the treated water, significant mussel kill can be achieved upon treatment with P. fluorescens strain CL0145A. These results further support the concept that this bacterium has significant potential for use as a zebra mussel control agent in power plant pipes receiving waters with a wide range of physical and chemical characteristics.

  18. Antibodies against equine herpesviruses in free-ranging mountain zebras from Namibia.

    PubMed

    Borchers, K; Frölich, K

    1997-10-01

    Twenty-one blood samples of free-ranging mountain zebras (Equus zebra) from Namibia were tested for equine herpesvirus (EHV-1, -2, -3, -4) specific antibodies by immunofluorescence assay (IFA) and neutralization test (NT). Additionally, type-specific nested polymerase chain reactions (nested PCR) were employed for detection of EHV-1, -2 and -4 DNA. Equine herpesvirus-1 antibodies were detected by IFA in all zebras, while only seven serum samples contained EHV-4 IFA antibodies. Sera with high IFA antibodies also were found to neutralize EHV-1 and -4. Furthermore, 20 zebras were EHV-2 seropositive by IFA, and one zebra had EHV-2 neutralizing antibodies. Equine herpesvirus-3 specific antibodies were not detected. We did not amplify EHV-1, -2 or -4 specific DNA sequences in peripheral blood leukocytes of the same zebras using type-specific nested PCR. EHV infections appear to be widespread in free-ranging zebras, as they are in domestic horses.

  19. IMPACT OF WATER TEMPERATURE ON ZEBRA MUSSEL MORTALITY

    SciTech Connect

    Daniel P. Molloy

    2002-08-07

    These tests conducted this past quarter have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels at water temperatures ranging from 7 to 23 C. Percent kill will likely be somewhat lower at very low temperatures, e.g., 7 C, but even at such low temperatures high mussel kill can still be achieved (>70% kill). This is significant because the development of a zebra mussel control method that is efficacious in such a wide range of temperatures broadens its usefulness as a potential commercial product.

  20. Multilocus genotypes from Charles Darwin's finches: biodiversity lost since the voyage of the Beagle.

    PubMed

    Petren, Kenneth; Grant, Peter R; Grant, B Rosemary; Clack, Andrew A; Lescano, Ninnia V

    2010-04-12

    Genetic analysis of museum specimens offers a direct window into a past that can predate the loss of extinct forms. We genotyped 18 Galápagos finches collected by Charles Darwin and companions during the voyage of the Beagle in 1835, and 22 specimens collected in 1901. Our goals were to determine if significant genetic diversity has been lost since the Beagle voyage and to determine the genetic source of specimens for which the collection locale was not recorded. Using 'ancient' DNA techniques, we quantified variation at 14 autosomal microsatellite loci. Assignment tests showed several museum specimens genetically matched recently field-sampled birds from their island of origin. Some were misclassified or were difficult to classify. Darwin's exceptionally large ground finches (Geospiza magnirostris) from Floreana and San Cristóbal were genetically distinct from several other currently existing populations. Sharp-beaked ground finches (Geospiza difficilis) from Floreana and Isabela were also genetically distinct. These four populations are currently extinct, yet they were more genetically distinct from congeners than many other species of Darwin's finches are from each other. We conclude that a significant amount of the finch biodiversity observed and collected by Darwin has been lost since the voyage of the Beagle. PMID:20194164

  1. Multilocus genotypes from Charles Darwin's finches: biodiversity lost since the voyage of the Beagle.

    PubMed

    Petren, Kenneth; Grant, Peter R; Grant, B Rosemary; Clack, Andrew A; Lescano, Ninnia V

    2010-04-12

    Genetic analysis of museum specimens offers a direct window into a past that can predate the loss of extinct forms. We genotyped 18 Galápagos finches collected by Charles Darwin and companions during the voyage of the Beagle in 1835, and 22 specimens collected in 1901. Our goals were to determine if significant genetic diversity has been lost since the Beagle voyage and to determine the genetic source of specimens for which the collection locale was not recorded. Using 'ancient' DNA techniques, we quantified variation at 14 autosomal microsatellite loci. Assignment tests showed several museum specimens genetically matched recently field-sampled birds from their island of origin. Some were misclassified or were difficult to classify. Darwin's exceptionally large ground finches (Geospiza magnirostris) from Floreana and San Cristóbal were genetically distinct from several other currently existing populations. Sharp-beaked ground finches (Geospiza difficilis) from Floreana and Isabela were also genetically distinct. These four populations are currently extinct, yet they were more genetically distinct from congeners than many other species of Darwin's finches are from each other. We conclude that a significant amount of the finch biodiversity observed and collected by Darwin has been lost since the voyage of the Beagle.

  2. Disruptive selection in a bimodal population of Darwin's finches.

    PubMed

    Hendry, Andrew P; Huber, Sarah K; De León, Luis F; Herrel, Anthony; Podos, Jeffrey

    2009-02-22

    A key part of the ecological theory of adaptive radiation is disruptive selection during periods of sympatry. Some insight into this process might be gained by studying populations that are bimodal for dual-context traits, i.e. those showing adaptive divergence and also contributing to reproductive isolation. A population meeting these criteria is the medium ground finch (Geospiza fortis) of El Garrapatero, Santa Cruz Island, Galápagos. We examined patterns of selection in this population by relating individual beak sizes to interannual recaptures during a prolonged drought. Supporting the theory, disruptive selection was strong between the two beak size modes. We also found some evidence of selection against individuals with the largest and smallest beak sizes, perhaps owing to competition with other species or to gaps in the underlying resource distribution. Selection may thus simultaneously maintain the current bimodality while also constraining further divergence. Spatial and temporal variation in G. fortis bimodality suggests a dynamic tug of war among factors such as selection and assortative mating, which may alternatively promote or constrain divergence during adaptive radiation.

  3. Disruptive selection in a bimodal population of Darwin's finches

    PubMed Central

    Hendry, Andrew P.; Huber, Sarah K.; De León, Luis F.; Herrel, Anthony; Podos, Jeffrey

    2008-01-01

    A key part of the ecological theory of adaptive radiation is disruptive selection during periods of sympatry. Some insight into this process might be gained by studying populations that are bimodal for dual-context traits, i.e. those showing adaptive divergence and also contributing to reproductive isolation. A population meeting these criteria is the medium ground finch (Geospiza fortis) of El Garrapatero, Santa Cruz Island, Galápagos. We examined patterns of selection in this population by relating individual beak sizes to interannual recaptures during a prolonged drought. Supporting the theory, disruptive selection was strong between the two beak size modes. We also found some evidence of selection against individuals with the largest and smallest beak sizes, perhaps owing to competition with other species or to gaps in the underlying resource distribution. Selection may thus simultaneously maintain the current bimodality while also constraining further divergence. Spatial and temporal variation in G. fortis bimodality suggests a dynamic tug of war among factors such as selection and assortative mating, which may alternatively promote or constrain divergence during adaptive radiation. PMID:18986971

  4. A simple explanation for the evolution of complex song syntax in Bengalese finches

    PubMed Central

    Katahira, Kentaro; Suzuki, Kenta; Kagawa, Hiroko; Okanoya, Kazuo

    2013-01-01

    The songs of Bengalese finches (Lonchura striata var. domestica) have complex syntax and provide an opportunity to investigate how complex sequential behaviour emerges via the evolutionary process. In this study, we suggest that a simple mechanism, i.e. many-to-one mapping from internal states onto syllables, may underlie the emergence of apparent complex syllable sequences that have higher order history dependencies. We analysed the songs of Bengalese finches and of their wild ancestor, the white-rumped munia (L. striata), whose songs are more stereotypical and simpler compared with those of Bengalese finches. The many-to-one mapping mechanism sufficiently accounted for the differences in the complexity of song syllable sequences of these two strains. PMID:24284561

  5. Zebra Mussel Monitoring and Control Guide. Final report

    SciTech Connect

    Not Available

    1992-12-01

    The Electric Power Research Institute (EPRI) Zebra Mussel Monitoring and Control Guide is a comprehensive compilation of US and European practices as reported in the open literature as of the end of 1992. EPRI considers the guide to be a living` document and will update it periodically in order to provide results of current research on chemical and nonchemical control technologies and utility experiences. The zebra mussel has infested all of the Great Lakes and other major rivers and waterways and is positioned to spread even more to the adjoining river basins. The impact of the zebra mussel on industrial power plantsis as a biofouler that clogs water systems and heat exchangers. This EPRI guideline identifies the zebra mussel, discusses its distribution in the United States, presents the potential threats to power plants, and presents the methods to initiate monitoring and control programs. Both preventive and corrective measures are presented. Preventive measures include various monitoring methods to initiate control techniques. The control techniques include both chemical and nonchemical together with combining techniques. Corrective methods include operational considerations, chemical cleaning, and mechanical/physical cleaning. It also may be possible to incorporate design changes, such as open to closed-loop backfit, backflushing, or pretreatment for closed systems. Various appendices are included that contain specifications to aid utilities in implementing several of the monitoring and control technologies, results of chemical evaluations at Cleveland Electric Illuminating Company plants, and data on the fate of various commercial molluscicides.

  6. Reducing costly zebra mussel infestations at power plants

    SciTech Connect

    Smythe, G.

    1994-10-01

    The fast-spreading-zebra mussel has significant potential to foul intakes and other water systems at North American hydro projects. Chemical controls can be effective in reducing infestations, but most have environmental and other drawbacks. Several non-chemical methods promise to help project operators reduce problems associated with the mussels.

  7. Effects of zebra chip disease on potato postharvest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zebra Chip (ZC), an emerging and economically important disease of potato in the United States, Mexico, Central America, and New Zealand, is causing losses of millions of dollars to the potato industry, occasionally leading to abandonment of entire fields. The disease is associated with the bacteriu...

  8. Tame zebra mussels at lower cost using ClO{sub 2}

    SciTech Connect

    Freymark, S.; Hale, L.

    1996-01-01

    A potential cost-effective alternative to other oxidizing molluscicides, chlorine dioxide applied intermittently apparently achieves equivalent control of veliger settlement in cooling systems. Various techniques have been used with success for controlling zebra mussel infestation. Powerplant owners, however, continue to search for methods to minimize treatment costs. One example is a nuclear station located on the eastern shore of Lake Michigan, which has been able to control the mollusk with chlorine (in the form of sodium hypochlorite, generated on-site), non-oxidizing biocide, and mechanical removal of adult mussels. Recently, the plant evaluated the possibility of substituting chlorine dioxide (ClO{sub 2}) to achieve the same result more economically, without additional impact on the environment. Results indicate that initial shock treatment with ClO{sub 2} followed by intermittent application during the spawning season can provide adequate control at a lower cost.

  9. Impact of European zebra mussel infestation to the electric power industry

    SciTech Connect

    McMahon, R.F. )

    1990-01-01

    This paper reports on Dreissena polymorpha, the European freshwater zebra mussel, introduced to the Great Lakes in 1985. It is now found throughout Lakes St. Clair and Erie, in Green Bay, Lake Michigan and invaded western Lake Ontario by Fall 1989. As its planktonic veliger larva is dispersed on water currents and adults are transported by human and natural vectors, it is likely to spread throughout U.S. and southern Canadian freshwaters. Mussel accumulations impede flow, and aggravate sedimentation and corrosion. Settlement occurs at flow velocities less than 1.5-2.0 m/sec. Mussels foul intake structures, low-flow piping, steam condensors, heat exchangers, fire protection systems, and cooling tower basins. Monitoring of source waters for mussels and veligers allows initiation of control measures before macrofouling occurs. Mussel fouling should be prevented as removal is difficult and expensive.

  10. On the Origin of the Zebra Pattern with Pulsating Superfine Structures on 21 April 2002

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Yan, Yihua

    2007-12-01

    Through the data around 3 GHz from the Radio Spectrometer in Huairou, Beijing, zebra-pattern structures from the 21 April 2002 event have been studied. Zebra stripes consist of periodically pulsating superfine structures in this event. An analysis of temporal profiles of intensities at multiple frequency channels shows that the Gaussian temporal profiles of pulse groups on zebra stripes are caused by drifting zebra stripes with Gaussian spectral profiles. The observed quasiperiodic pulsations with about 30 ms period have a peculiar feature of oscillation near a steady state, probably resulting from relaxation oscillations, which modulate the electron cyclotron maser emission that forms the zebra stripes during the process of wave particle interactions. All the main properties of the zebra stripes with pulsating superfine structures indicate that the double plasma resonance model might be the most suitable one, with the relaxation oscillations, to form the superfine structures. The model of LaBelle et al. ( Astrophys. J. 593, 1195, 2003) could not account for the observed properties of zebra-pattern structures in this event nor for most zebra-pattern structures occupying a wide frequency range, mainly because the allowable frequency range of the zebra-pattern structures in their model is too narrow to reproduce the observed zebras.

  11. Frequency variations of solar radio zebras and their power-law spectra

    NASA Astrophysics Data System (ADS)

    Karlický, M.

    2014-01-01

    Context. During solar flares several types of radio bursts are observed. The fine striped structures of the type IV solar radio bursts are called zebras. Analyzing them provides important information about the plasma parameters of their radio sources. We present a new analysis of zebras. Aims: Power spectra of the frequency variations of zebras are computed to estimate the spectra of the plasma density variations in radio zebra sources. Methods: Frequency variations of zebra lines and the high-frequency boundary of the whole radio burst were determined with and without the frequency fitting. The computed time dependencies of these variations were analyzed with the Fourier method. Results: First, we computed the variation spectrum of the high-frequency boundary of the whole radio burst, which is composed of several zebra patterns. This power spectrum has a power-law form with a power-law index -1.65. Then, we selected three well-defined zebra-lines in three different zebra patterns and computed the spectra of their frequency variations. The power-law indices in these cases are found to be in the interval between -1.61 and -1.75. Finally, assuming that the zebra-line frequency is generated on the upper-hybrid frequency and that the plasma frequency ωpe is much higher than the electron-cyclotron frequency ωce, the Fourier power spectra are interpreted to be those of the electron plasma density in zebra radio sources.

  12. Strange star admitting Chaplygin equation of state in Finch-Skea spacetime

    NASA Astrophysics Data System (ADS)

    Bhar, Piyali

    2015-10-01

    In the present paper we propose a new model of an anisotropic strange star which admits the Chaplygin equation of state. The exterior spacetime is described by a Schwarzschild line element. The model is developed by assuming the Finch-Skea ansatz (Finch and Skea in Class. Quantum Gravity 6:467, 1989. We obtain the model parameters in closed form. Our model is free from a central singularity. Choosing some particular values for the parameter we show that our model corroborates the observational data of the strange star PSR J1614-2230 (Gangopadhyay et al. in Mon. Not. R. Astron. Soc. 431:3216, 2013.

  13. Every inch a finch: a commentary on Grant (1993) ‘Hybridization of Darwin's finches on Isla Daphne Major, Galapagos’

    PubMed Central

    Bell, Graham

    2015-01-01

    One of the most familiar features of the natural world is that most animals and plants fall into distinct categories known as species. The attempt to understand the nature of species and the origin of new species was the enterprise that drove the early development of evolutionary biology and has continued to be a major focus of research. Individuals belonging to the same species usually share a distinctive appearance and way of life, and they can mate together successfully and produce viable offspring. New species may evolve, therefore, either through ecological divergence or through sexual isolation. The balance between these processes will depend on the extent of hybridization, especially in the early stages of divergence. Detecting and measuring hybridization in natural populations, however, requires intensive, long-term field programmes that are seldom undertaken, leaving a gap in our understanding of species formation. The finch community of a small, isolated island in the Galapagos provided an opportunity to discover how frequently hybridization takes place between closely related species in a pristine location, and Peter Grant's paper, published in Philosophical Transactions B in 1993, reports the observations that he and his collaborators made during the first 20 years of what is now one of the classical studies of evolution in action. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750230

  14. Every inch a finch: a commentary on Grant (1993) 'Hybridization of Darwin's finches on Isla Daphne Major, Galapagos'.

    PubMed

    Bell, Graham

    2015-04-19

    One of the most familiar features of the natural world is that most animals and plants fall into distinct categories known as species. The attempt to understand the nature of species and the origin of new species was the enterprise that drove the early development of evolutionary biology and has continued to be a major focus of research. Individuals belonging to the same species usually share a distinctive appearance and way of life, and they can mate together successfully and produce viable offspring. New species may evolve, therefore, either through ecological divergence or through sexual isolation. The balance between these processes will depend on the extent of hybridization, especially in the early stages of divergence. Detecting and measuring hybridization in natural populations, however, requires intensive, long-term field programmes that are seldom undertaken, leaving a gap in our understanding of species formation. The finch community of a small, isolated island in the Galapagos provided an opportunity to discover how frequently hybridization takes place between closely related species in a pristine location, and Peter Grant's paper, published in Philosophical Transactions B in 1993, reports the observations that he and his collaborators made during the first 20 years of what is now one of the classical studies of evolution in action. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.

  15. The effect of zebra mussel consumption on growth of freshwater drum in Lake Erie

    USGS Publications Warehouse

    French, John R. P.; Bur, Michael T.

    1996-01-01

    We examined food habits and scale annuli of freshwater drum (Aplodinotus grunniens) from western Lake Erie to determine whether increasing predation on zebra mussels (Dreissena polymorpha) had affected growth of freshwater drum. The volume of zebra mussels in drum guts was greater in older fish. Growth of age classes 3–4, which consumed few zebra mussels, was greater in the most productive year for zebra mussels, July 1990–August 1991, than in three prior years. The total lengths of 5-year-old drum changed little. The mean total length of 6-year-old females has declined since the zebra mussel invaded Lake Erie, even through mussels comprised more than two-thirds of gut samples in these fish. These studies suggest that zebra mussels may not benefit freshwater drum when serving as a staple in the diet. PDF

  16. Proceedings of the fifth international zebra mussel and other aquatic nuisance organisms conference 1995

    SciTech Connect

    Ackerman, J.D.

    1995-06-01

    This report contains articles from the proceedings of the fifth international zebra mussel & other aquatic nuisance organisms conference. Topics include articles on: Zebra mussel life history; Strategies for application of non-oxidizing biocides; examination of the potential of chlorine dioxide for use in zebra mussel veliger control; and ballast water control; overview of the Canadian approach. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  17. Lesser scaup forage on zebra mussels at Cook nuclear plant, Michigan

    USGS Publications Warehouse

    Mitchell, C.A.; Carlson, J.

    1993-01-01

    Nineteen of 21 Lesser Scaup (Aythya affinis) entrained while foraging at the water intake structures of Cook Nuclear Plant, Bridgman, Michigan had consumed zebra mussels (Dreissena polymorpha). The average number of zebra mussels in the upper gastrointestinal tract was 260; maximum number was 987. Migrating Lesser Scaup found this new food source during the first winter following settlement of zebra mussels on the water intake structures of the power plant.

  18. Do zebra mussels (Dreissena polymorpha) alter lake water chemistry in a way that favours Microcystis growth?

    PubMed

    Bykova, Olga; Laursen, Andrew; Bostan, Vadim; Bautista, Joseph; McCarthy, Lynda

    2006-12-01

    This study examined possible relationships between the presence of zebra mussels (Dreissena polymorpha) and Microcystis spp. abundance. Experiments were conducted in 12 microcosms designed to mimic shallow lake ecosystems. Fresh, aerated water with phytoplankton (pseudokirchneriella spp. and Microcystis spp.) was pumped into each microcosm daily to ensure zebra mussels were exposed to oxygen and food. Microcosms containing zebra mussels experienced significantly higher fluxes of nitrate (p=0.019) and lower fluxes of ortho-phosphate (p=0.047) into sediments. In a second experiment, water column nutrient concentrations were compared in microcosms with and without live zebra mussels. Consistent with results of the previous experiment, microcosms with zebra mussels had significantly less nitrate (p=0.023) and organic nitrogen (p=0.003) in the water column, while ammonium (p=0.074), phosphate (p=0.491), and dissolved organic carbon (p=0.820) in the water column were not different between microcosms with or without zebra mussels. Microcosms with zebra mussels also experienced a reduction in green algae (pseudokirchneriella) (p<0.001) and an increase in abundance of Microcystis (p<0.001) relative to microcosms without zebra mussels. In an experiment without zebra mussels, nutrient ratios (N/P) were manipulated to determine potential links between N/P and relative abundance of each phytoplankton. Manipulation of N/P was intended to mimic differences observed in microcosms with and without zebra mussels in the previous experiment. Low N/P (mimicking microcosms with zebra mussels) was related to an increase in Microcystis (p<0.001) and Microcystis/Pseudokirchneriella biovolume (p<0.001). It is this shift in N/P, and possibly some level of selective feeding, that is believed to have driven changes in the relative abundance of Microcystis. In lakes invaded by zebra mussels, alterations in the processing of nitrogen and phosphorus could contribute to the re-emergence of

  19. Do apprehended saffron finches know how to survive predators? A careful look at reintroduction candidates.

    PubMed

    Dutra, Luisa Mascarenhas Ladeia; Young, Robert John; Galdino, Conrado Aleksander Barbosa; Vasconcellos, Angélica da Silva

    2016-04-01

    Wildlife trafficking is a major factor contributing to the reduction of biological diversity. In Brazil, trafficked animals are apprehended by environmental agencies and released in the wild. The maintenance of wild animals in captivity may jeopardize their survival in the wild, for example, by reducing their ability to recognize a predator. Saffron finches (Sicalis flaveola) are among the most trafficked Brazilian birds. Twenty-eight apprehended saffron finches were submitted to Temperament and Predator-recognition tests, with presentation of predator and non-predator models: a live and a taxidermised hawk, a taxidermised armadillo and a Lego cube. The captive saffron finches have retained general anti-predator responses, such as increasing alertness, avoiding back-facing and keeping distance when presented with potential predators. The birds responded more strongly to the live hawk than to the cube. Although some responses to the other stimuli were not statistically different from each other, a decrease in intensity of response with the decrease in threat level was remarkable. We found no relationship between temperament traits and responses to predators: a possible consequence of husbandry practices in captivity. Our results indicate saffron finches may retain basic anti-predator responses in captivity, which favours release and reintroduction programmes: information relevant for conservation management. PMID:26827615

  20. Influenza A(H7N9) Virus Transmission between Finches and Poultry

    PubMed Central

    Jones, Jeremy C.; Sonnberg, Stephanie; Webby, Richard J.

    2015-01-01

    Low pathogenicity avian influenza A(H7N9) virus has been detected in poultry since 2013, and the virus has caused >450 infections in humans. The mode of subtype H7N9 virus transmission between avian species remains largely unknown, but various wild birds have been implicated as a source of transmission. H7N9 virus was recently detected in a wild sparrow in Shanghai, China, and passerine birds, such as finches, which share space and resources with wild migratory birds, poultry, and humans, can be productively infected with the virus. We demonstrate that interspecies transmission of H7N9 virus occurs readily between society finches and bobwhite quail but only sporadically between finches and chickens. Inoculated finches are better able to infect naive poultry than the reverse. Transmission occurs through shared water but not through the airborne route. It is therefore conceivable that passerine birds may serve as vectors for dissemination of H7N9 virus to domestic poultry. PMID:25811839

  1. Influenza A(H7N9) virus transmission between finches and poultry.

    PubMed

    Jones, Jeremy C; Sonnberg, Stephanie; Webby, Richard J; Webster, Robert G

    2015-04-01

    Low pathogenicity avian influenza A(H7N9) virus has been detected in poultry since 2013, and the virus has caused >450 infections in humans. The mode of subtype H7N9 virus transmission between avian species remains largely unknown, but various wild birds have been implicated as a source of transmission. H7N9 virus was recently detected in a wild sparrow in Shanghai, China, and passerine birds, such as finches, which share space and resources with wild migratory birds, poultry, and humans, can be productively infected with the virus. We demonstrate that interspecies transmission of H7N9 virus occurs readily between society finches and bobwhite quail but only sporadically between finches and chickens. Inoculated finches are better able to infect naive poultry than the reverse. Transmission occurs through shared water but not through the airborne route. It is therefore conceivable that passerine birds may serve as vectors for dissemination of H7N9 virus to domestic poultry.

  2. On the Hypothetico-Deductive Nature of Science--Darwin's Finches

    ERIC Educational Resources Information Center

    Lawson, Anton E.

    2009-01-01

    Allchin (2006) has misinterpreted a classic case of hypothetico-deductive (HD) science in terms of his preferred "let's-gather-some-data-and-see-what-emerges" view. The misrepresentation concerns the research program of Peter and Rosemary Grant on Darwin's finches. The present essay argues that the Grants' research is HD in nature and includes a…

  3. Do apprehended saffron finches know how to survive predators? A careful look at reintroduction candidates.

    PubMed

    Dutra, Luisa Mascarenhas Ladeia; Young, Robert John; Galdino, Conrado Aleksander Barbosa; Vasconcellos, Angélica da Silva

    2016-04-01

    Wildlife trafficking is a major factor contributing to the reduction of biological diversity. In Brazil, trafficked animals are apprehended by environmental agencies and released in the wild. The maintenance of wild animals in captivity may jeopardize their survival in the wild, for example, by reducing their ability to recognize a predator. Saffron finches (Sicalis flaveola) are among the most trafficked Brazilian birds. Twenty-eight apprehended saffron finches were submitted to Temperament and Predator-recognition tests, with presentation of predator and non-predator models: a live and a taxidermised hawk, a taxidermised armadillo and a Lego cube. The captive saffron finches have retained general anti-predator responses, such as increasing alertness, avoiding back-facing and keeping distance when presented with potential predators. The birds responded more strongly to the live hawk than to the cube. Although some responses to the other stimuli were not statistically different from each other, a decrease in intensity of response with the decrease in threat level was remarkable. We found no relationship between temperament traits and responses to predators: a possible consequence of husbandry practices in captivity. Our results indicate saffron finches may retain basic anti-predator responses in captivity, which favours release and reintroduction programmes: information relevant for conservation management.

  4. Mechanical stress, fracture risk and beak evolution in Darwin's ground finches (Geospiza)

    PubMed Central

    Soons, Joris; Herrel, Anthony; Genbrugge, Annelies; Aerts, Peter; Podos, Jeffrey; Adriaens, Dominique; de Witte, Yoni; Jacobs, Patric; Dirckx, Joris

    2010-01-01

    Darwin's finches have radiated from a common ancestor into 14 descendent species, each specializing on distinct food resources and evolving divergent beak forms. Beak morphology in the ground finches (Geospiza) has been shown to evolve via natural selection in response to variation in food type, food availability and interspecific competition for food. From a mechanical perspective, however, beak size and shape are only indirectly related to birds' abilities to crack seeds, and beak form is hypothesized to evolve mainly under selection for fracture avoidance. Here, we test the fracture-avoidance hypothesis using finite-element modelling. We find that across species, mechanical loading is similar and approaches reported values of bone strength, thus suggesting pervasive selection on fracture avoidance. Additionally, deep and wide beaks are better suited for dissipating stress than are more elongate beaks when scaled to common sizes and loadings. Our results illustrate that deep and wide beaks in ground finches enable reduction of areas with high stress and peak stress magnitudes, allowing birds to crack hard seeds while limiting the risk of beak failure. These results may explain strong selection on beak depth and width in natural populations of Darwin's finches. PMID:20194171

  5. Regions of Generation and Optical Thicknesses of dm-Zebra Lines

    NASA Astrophysics Data System (ADS)

    Yasnov, L. V.; Karlický, M.

    2015-07-01

    Using a new model based on the double plasma resonance (DPR), we show that the zebra structure seen in solar radio bursts is generated in the transition region and at the tops of the magnetic arcade. The magnetic field in zebra sources is probably weaker than 150 gauss. According to this model, a generation of zebras in stronger magnetic fields is improbable. The high-frequency boundary of decimetric zebras depends on the background electron plasma density, but not on the magnetic field strength in the generation regions. The bremsstrahlung absorption in atmospheric layers above the DPR zebra generation region and the cyclotron absorption in the DPR region and in the gyroresonance layers at higher altitudes limit the spectrum of zebras from both high-frequency and low-frequency sides. While the bremsstrahlung reduces the emission from the high-frequency side, the cyclotron absorption limits the low-frequency side. The observed frequency range and the number of observed zebra lines are determined not only by these absorptions, but also by appropriate distribution functions of superthermal electrons and plasma conditions in this region. Low-frequency (metric) zebra emissions can be generated at high altitudes. Computations show that such emissions can escape from the DPR generation region only at high gyro-harmonics () and with many zebra lines.

  6. The Effect of Zebra Mussels on Algal Community Structure in an Impounded River System

    NASA Astrophysics Data System (ADS)

    Trumble, A. F.; Luttenton, M.

    2005-05-01

    The zebra mussel, Dreissena polymorpha, invaded the Great Lakes Region in the mid 1980's, and subsequently colonized inland lakes and coastal river systems through secondary invasions. The Muskegon River below Croton Dam was colonized by zebra mussels in 2000 following their introduction into Croton impoundment in the late 1990's. No zebra mussels were found below Croton Dam in 1999 but had increased to 25,000 m-2 by 2001. We examined the affect of zebra mussels on epilithic periphyton communities by comparing plots that were and were not colonized by zebra mussels. Chlorophyll a increased in both treatments over time but was significantly higher in control plots than in zebra mussel plots. The concentration of chlorophyll a in the control plots increased from 14 µgcm-2 to 26 µgcm-2 and the concentration in the zebra mussel plots started at 12 µgcm-2, peaked at 19 µgcm-2, and then decreased to 15 µgcm-2 over a 6 week period. In a related experiment using artificial streams, chlorophyll a increased with increasing zebra mussel density, but differences were not significant. The different trends observed between the two experiments may be explained in part by arthropod invertebrates associated with zebra mussel populations.

  7. Changes in corticosterone concentrations and behavior during Mycoplasma gallisepticum infection in house finches (Haemorhous mexicanus).

    PubMed

    Love, Ashley C; Foltz, Sarah L; Adelman, James S; Moore, Ignacio T; Hawley, Dana M

    2016-09-01

    Glucocorticoid stress hormones are important for energy mobilization as well as regulation of the immune system, and thus these hormones are particularly likely to both influence and respond to pathogen infection in vertebrates. In this study, we examined how the glucocorticoid stress response in house finches (Haemorhous mexicanus) interacts with experimental infection of the naturally-occurring bacterial pathogen, Mycoplasma gallisepticum (MG). We also investigated whether infection-induced concentrations of corticosterone (CORT), the primary glucocorticoid in birds, were associated with the expression of sickness behavior, the lethargy typically observed in vertebrates early in infection. We found that experimental infection with MG resulted in significantly higher CORT levels on day 5 post-infection, but this effect appeared to be limited to female house finches only. Regardless of sex, infected individuals with greater disease severity had the highest CORT concentrations on day 5 post-infection. House finches exposed to MG exhibited behavioral changes, with infected birds having significantly lower activity levels than sham-inoculated individuals. However, CORT concentrations and the extent of sickness behaviors exhibited among infected birds were not associated. Finally, pre-infection CORT concentrations were associated with reduced inflammation and pathogen load in inoculated males, but not females. Our results suggest that the house finch glucocorticoid stress response may both influence and respond to MG infection in sex-specific ways, but because we had a relatively low sample size of males, future work should confirm these patterns. Finally, manipulative experiments should be performed to test whether the glucocorticoid stress response acts as a brake on the inflammatory response associated with MG infection in house finches.

  8. Electric utility Zebra Mussel Control technology conference: Proceedings

    SciTech Connect

    Tsou, J.L. ); Mussalli, Y.G. )

    1992-03-01

    This Conference on Zebra Mussel Control technology was held on October 22--23, 1991 in Itasca (Chicago), Illinois. The Conference was sponsored by EPRI Zebra Mussel Task Force and hosted by Commonwealth Edison Company to bring together representatives of utilities, manufacturers, researches, and consultants. Nineteen papers were presented in three sessions. These sessions were devoted to the following topics: Overview and Control Strategy, Monitoring and Non-Chemical Control Technology, and Chemical Control Technology. A half-day workshop/panel discussion devoted to the same topics was conducted at the second day of the formal presentations. More than 160 people attended this Conference. This report contains technical papers and summaries of the workshop/panel sessions. Of these 19 papers, there are 4 papers related to overview and control strategy, 7 papers related to monitoring and non-chemical control technology, and 8 papers related to chemical control technology.

  9. Annually recurring parthenogenesis in a zebra shark Stegostoma fasciatum.

    PubMed

    Robinson, D P; Baverstock, W; Al-Jaru, A; Hyland, K; Khazanehdari, K A

    2011-11-01

    A zebra shark, Stegostoma fasciatum, held in captivity at the Burj Al Arab aquarium, produced embryos and pups in the absence of a male. A total of 15 pups were produced from eggs laid within the aquarium over a period of four consecutive years commencing 2007. Parthenogenesis was confirmed through DNA analysis for three pups sampled during the first two consecutive egg cycles and is presumed to be the method of reproduction responsible thereafter. PMID:22026614

  10. Standing sedation in captive zebra (Equus grevyi and Equus burchellii).

    PubMed

    Hoyer, Mark; de Jong, Sara; Verstappen, Frank; Wolters, Marno

    2012-03-01

    Nine Grevy's zebras (Equus grevyi) and three Burchell's zebras (Equus burchellii) were immobilized in a standing position a total of 70 times for minor, nonpainful procedures over a 9-yr period. Standing sedation was successfully obtained with a combination of detomidine and butorphanol on 47 occasions (67.1%). Detomidine i.m. (median 0.10 mg/kg; range: 0.07-0.21) was administered by dart, followed 10 min later by butorphanol i.m. (median 0.13 mg/kg; range 0.04-0.24). The dosages were varied depending on the initial demeanor of the animal. On 23 occasions (32.9%), small amounts of etorphine (median 2.5 microg/kg; range 1.1-12.3 microg/kg) plus acepromazine (median 10 microg/kg; range 4.4-50 microg/kg) (as in Large Animal-Immobilon) had to be administered i.m. to gain sufficient sedation. In these latter cases, the animals were either excited or known for their aggressive character. The zebras were sufficiently immobilized for the length of most procedures (<45 min) without supplementation. At the end of the procedure, the animals were given atipamezole (2 mg per 1 mg detomidine used) and naltrexone (0.1 mg/kg) to reverse the sedative effects, irrespective of whether etorphine was used or not. Standing sedation, using the combination of the alpha-2 agonist detomidine and the partial agonist-antagonist opioid butorphanol (in some cases supplemented with etorphine + acepromazine), proved to be a very efficacious and safe method to be used in zebras under zoo conditions for short-lasting, nonpainful procedures.

  11. The first complete mitochondrial genome of the Maylandia zebra.

    PubMed

    Xia, Yan; Dang, Xiao; Xu, Qiwu; Zhang, Dongya

    2016-09-01

    Maylandia zebra, a member of the family cichlid living in individual African lakes, are regarded as a significant evolution model. Recently the genome sequencing had been done, but there is no sufficient information about its mitochondria. Herein, we first assembled the complete mitochondrial genome sequence of Maylandia zebra. It is a 16 582 bp long sequence with most mitogenome's characteristic structure, 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and 1 putative control region. The GC-content of our fresh sequence is 45.86%, similar to closely related species Oreochromis niloticus. The accuracy and utility of new determined mitogenome sequences can be verified by the phylogenetic analysis, based on whole mitogenome alignment with Neolamprologus brichardi, Pseudotropheus crabro, Oreochromis niloticu, which is closest relative to Maylandia zebra, and 6 others. Using the full mitogenome, we expect to address taxonomic issues and study the related evolution events. Moreover, this is the first report of the mitogenome of genus Maylandia. PMID:27158870

  12. Zebra mussel control using periodic chlorine dioxide treatments

    SciTech Connect

    Tsou, J.; Coyle, J.; Crone, D.

    1996-08-01

    This paper summarizes the EPRI report (TR-105202) on the same topic as well as presents changes in current thinking on the suitability (applicability) of chlorine dioxide for fouling control. Chlorine dioxide was tested as a zebra mussel biocide at two steam electric generating stations in Illinois and one in Indiana. The purpose of these studies was to determine the efficacy of chlorine dioxide in killing zebra mussels and to develop site specific treatment programs for the three utilities. The Electric Power Research Institute (EPRI) Zebra Mussel Consortium sponsored the testing of this recent use of chlorine dioxide. The raw water system at Central Illinois Public Service`s Meredosia Station, on the Illinois River, received applications of chlorine dioxide in April, July, and September 1994. The raw water system at Illinois Power Company`s Wood River Station, on the Mississippi River, received applications in July 1993, January, April, May, July, and September 1994. The Gallagher Station, on the Ohio River, was treated in July and October 1994. Chlorine dioxide was generated on-site and injected into the water intake structure. Both cooling and service water systems were treated at the facilities. 6 refs., 13 figs.

  13. Evidence for aggressive mimicry in an adult brood parasitic bird, and generalized defences in its host.

    PubMed

    Feeney, W E; Troscianko, J; Langmore, N E; Spottiswoode, C N

    2015-07-01

    Mimicry of a harmless model (aggressive mimicry) is used by egg, chick and fledgling brood parasites that resemble the host's own eggs, chicks and fledglings. However, aggressive mimicry may also evolve in adult brood parasites, to avoid attack from hosts and/or manipulate their perception of parasitism risk. We tested the hypothesis that female cuckoo finches (Anomalospiza imberbis) are aggressive mimics of female Euplectes weavers, such as the harmless, abundant and sympatric southern red bishop (Euplectes orix). We show that female cuckoo finch plumage colour and pattern more closely resembled those of Euplectes weavers (putative models) than Vidua finches (closest relatives); that their tawny-flanked prinia (Prinia subflava) hosts were equally aggressive towards female cuckoo finches and southern red bishops, and more aggressive to both than to their male counterparts; and that prinias were equally likely to reject an egg after seeing a female cuckoo finch or bishop, and more likely to do so than after seeing a male bishop near their nest. This is, to our knowledge, the first quantitative evidence for aggressive mimicry in an adult bird, and suggests that host-parasite coevolution can select for aggressive mimicry by avian brood parasites, and counter-defences by hosts, at all stages of the reproductive cycle. PMID:26063850

  14. Evidence for aggressive mimicry in an adult brood parasitic bird, and generalized defences in its host

    PubMed Central

    Feeney, W. E.; Troscianko, J.; Langmore, N. E.; Spottiswoode, C. N.

    2015-01-01

    Mimicry of a harmless model (aggressive mimicry) is used by egg, chick and fledgling brood parasites that resemble the host's own eggs, chicks and fledglings. However, aggressive mimicry may also evolve in adult brood parasites, to avoid attack from hosts and/or manipulate their perception of parasitism risk. We tested the hypothesis that female cuckoo finches (Anomalospiza imberbis) are aggressive mimics of female Euplectes weavers, such as the harmless, abundant and sympatric southern red bishop (Euplectes orix). We show that female cuckoo finch plumage colour and pattern more closely resembled those of Euplectes weavers (putative models) than Vidua finches (closest relatives); that their tawny-flanked prinia (Prinia subflava) hosts were equally aggressive towards female cuckoo finches and southern red bishops, and more aggressive to both than to their male counterparts; and that prinias were equally likely to reject an egg after seeing a female cuckoo finch or bishop, and more likely to do so than after seeing a male bishop near their nest. This is, to our knowledge, the first quantitative evidence for aggressive mimicry in an adult bird, and suggests that host–parasite coevolution can select for aggressive mimicry by avian brood parasites, and counter-defences by hosts, at all stages of the reproductive cycle. PMID:26063850

  15. Evidence for aggressive mimicry in an adult brood parasitic bird, and generalized defences in its host.

    PubMed

    Feeney, W E; Troscianko, J; Langmore, N E; Spottiswoode, C N

    2015-07-01

    Mimicry of a harmless model (aggressive mimicry) is used by egg, chick and fledgling brood parasites that resemble the host's own eggs, chicks and fledglings. However, aggressive mimicry may also evolve in adult brood parasites, to avoid attack from hosts and/or manipulate their perception of parasitism risk. We tested the hypothesis that female cuckoo finches (Anomalospiza imberbis) are aggressive mimics of female Euplectes weavers, such as the harmless, abundant and sympatric southern red bishop (Euplectes orix). We show that female cuckoo finch plumage colour and pattern more closely resembled those of Euplectes weavers (putative models) than Vidua finches (closest relatives); that their tawny-flanked prinia (Prinia subflava) hosts were equally aggressive towards female cuckoo finches and southern red bishops, and more aggressive to both than to their male counterparts; and that prinias were equally likely to reject an egg after seeing a female cuckoo finch or bishop, and more likely to do so than after seeing a male bishop near their nest. This is, to our knowledge, the first quantitative evidence for aggressive mimicry in an adult bird, and suggests that host-parasite coevolution can select for aggressive mimicry by avian brood parasites, and counter-defences by hosts, at all stages of the reproductive cycle.

  16. Divergence and gene flow among Darwin's finches: a genome-wide view of adaptive radiation driven by interspecies allele sharing

    PubMed Central

    Palmer, Daniela H.; Kronforst, Marcus R.

    2015-01-01

    A recent analysis of the genomes of Darwin's finches revealed extensive interspecies allele sharing throughout the history of the radiation and identified a key locus responsible for morphological evolution in this group. The radiation of Darwin's finches on the Galápagos archipelago has long been regarded as an iconic study system for field ecology and evolutionary biology. Coupled with an extensive history of field work, these latest findings affirm the increasing acceptance of introgressive hybridization, or gene flow between species, as a significant contributor to adaptive evolution. Here we review and discuss these findings in relation to both classical work on Darwin's finches and contemporary work showing similar evolutionary signatures in other biological systems. The continued unification of genomic data with field biology promises to further elucidate the molecular basis of adaptation in Darwin's finches and well beyond. PMID:26200327

  17. Variable light environments induce plastic spectral tuning by regional opsin coexpression in the African cichlid fish, Metriaclima zebra.

    PubMed

    Dalton, Brian E; Lu, Jessica; Leips, Jeff; Cronin, Thomas W; Carleton, Karen L

    2015-08-01

    Critical behaviours such as predation and mate choice often depend on vision. Visual systems are sensitive to the spectrum of light in their environment, which can vary extensively both within and among habitats. Evolutionary changes in spectral sensitivity contribute to divergence and speciation. Spectral sensitivity of the retina is primarily determined by visual pigments, which are opsin proteins bound to a chromophore. We recently discovered that photoreceptors in different regions of the retina, which view objects against distinct environmental backgrounds, coexpress different pairs of opsins in an African cichlid fish, Metriaclima zebra. This coexpression tunes the sensitivity of the retinal regions to the corresponding backgrounds and may aid in detection of dark objects, such as predators. Although intraretinal regionalization of spectral sensitivity in many animals correlates with their light environments, it is unknown whether variation in the light environment induces developmentally plastic alterations of intraretinal sensitivity regions. Here, we demonstrate with fluorescent in situ hybridization and qPCR that the spectrum and angle of environmental light both influence the development of spectral sensitivity regions by altering the distribution and level of opsins across the retina. Normally, M. zebra coexpresses LWS opsin with RH2Aα opsin in double cones of the ventral but not the dorsal retina. However, when illuminated from below throughout development, adult M. zebra coexpressed LWS and RH2Aα in double cones both dorsally and ventrally. Thus, environmental background spectra alter the spectral sensitivity pattern that develops across the retina, potentially influencing behaviours and related evolutionary processes such as courtship and speciation. PMID:26175094

  18. Variable light environments induce plastic spectral tuning by regional opsin coexpression in the African cichlid fish, Metriaclima zebra

    PubMed Central

    Dalton, Brian E.; Lu, Jessica; Leips, Jeff; Cronin, Thomas W.; Carleton, Karen L.

    2015-01-01

    Critical behaviors such as predation and mate choice often depend on vision. Visual systems are sensitive to the spectrum of light in their environment, which can vary extensively both within and among habitats. Evolutionary changes in spectral sensitivity contribute to divergence and speciation. Spectral sensitivity of the retina is primarily determined by visual pigments, which are opsin proteins bound to a chromophore. We recently discovered that photoreceptors in different regions of the retina, which view objects against distinct environmental backgrounds, coexpress different pairs of opsins in an African cichlid fish, Metriaclima zebra. This coexpression tunes the sensitivity of the retinal regions to the corresponding backgrounds and may aid detection of dark objects, such as predators. Although intraretinal regionalization of spectral sensitivity in many animals correlates with their light environments, it is unknown whether variation in the light environment induces developmentally plastic alterations of intraretinal sensitivity regions. Here, we demonstrate with fluorescent in situ hybridization and qPCR that the spectrum and angle of environmental light both influence the development of spectral sensitivity regions by altering the distribution and level of opsins across the retina. Normally M. zebra coexpresses LWS opsin with RH2Aα opsin in double cones of the ventral but not the dorsal retina. However, when illuminated from below throughout development, adult M. zebra coexpressed LWS and RH2Aα in double cones both dorsally and ventrally. Thus, environmental background spectra alter the spectral sensitivity pattern that develops across the retina, potentially influencing behaviors and related evolutionary processes such as courtship and speciation. PMID:26175094

  19. First description of the breeding biology and natural history of the ochre-breasted brush finch atlapetes semirufus in venezuela

    USGS Publications Warehouse

    Biancucci, L.; Martin, T.E.

    2008-01-01

    We provide the first description of the eggs, breeding biology, and natural history of the Ochre-breasted Brush Finch (Atlapetes semirufus). We found 37 nests over four breeding seasons (2004-2007) in Yacamb?? National Park, Venezuela. Nesting activity started in late April and continued until early June suggesting single-brooded behavior despite a typical tropical clutch size of two eggs (x?? = 1.89) that were laid on consecutive days. Egg mass averaged 3.38 g and 11.6% of adult female mass. The incubation and nestling periods averaged 14.9 and 10.5 days, respectively. Only females incubated and the percent time they spent incubating did not change between early and late incubation. Females brooded 42.7% of the time when nestlings were 2 days of age and 20.5% when 9 days of age. Both parents provisioned young at a low rate (3.9 trips/hr) and nestling growth rate (k = 0.45) was also slow. Nest predation rates were relatively high with daily mortality rates of 0.058 and 0.067 during incubation and nestling stages, respectively.

  20. Evaluation of zebra mussels (Dreissena polymorpha) as biomonitors of mercury contamination in aquatic ecosystems.

    PubMed

    Blackwell, Bradley D; Driscoll, Charles T; Spada, Michael E; Todorova, Svetoslava G; Montesdeoca, Mario R

    2013-03-01

    Zebra mussels have invaded many lakes in the United States and could be a useful tool for monitoring responses of aquatic biota to changes in mercury loading. The goal of the present study was to evaluate zebra mussels for use as a biomonitor of mercury contamination by comparing zebra mussel mercury concentrations between a lake with only indirect atmospheric mercury contamination (Otisco Lake, NY, USA) and a lake that was directly contaminated by mercury discharges (Onondaga Lake, NY, USA). Zebra mussels were sampled in both the spring and fall of 2004 and 2005. Total mercury (THg) concentrations in zebra mussels were approximately seven times greater in Onondaga Lake than in Otisco Lake, and water column mercury concentrations differed by an order of magnitude between the two lakes. Seasonal differences resulted in significantly higher zebra mussel THg concentrations during the fall for both lakes. There was also significant variation among different sampling sites in Onondaga Lake. Mussel methylmercury concentrations averaged 53% of THg concentrations but were highly variable. Strong relationships between water column THg and zebra mussel THg suggest that zebra mussels are a good indicator of aquatic mercury concentrations and could be used as an effective biomonitor of mercury contamination in aquatic ecosystems. PMID:23280672

  1. Evaluation of zebra mussels (Dreissena polymorpha) as biomonitors of mercury contamination in aquatic ecosystems.

    PubMed

    Blackwell, Bradley D; Driscoll, Charles T; Spada, Michael E; Todorova, Svetoslava G; Montesdeoca, Mario R

    2013-03-01

    Zebra mussels have invaded many lakes in the United States and could be a useful tool for monitoring responses of aquatic biota to changes in mercury loading. The goal of the present study was to evaluate zebra mussels for use as a biomonitor of mercury contamination by comparing zebra mussel mercury concentrations between a lake with only indirect atmospheric mercury contamination (Otisco Lake, NY, USA) and a lake that was directly contaminated by mercury discharges (Onondaga Lake, NY, USA). Zebra mussels were sampled in both the spring and fall of 2004 and 2005. Total mercury (THg) concentrations in zebra mussels were approximately seven times greater in Onondaga Lake than in Otisco Lake, and water column mercury concentrations differed by an order of magnitude between the two lakes. Seasonal differences resulted in significantly higher zebra mussel THg concentrations during the fall for both lakes. There was also significant variation among different sampling sites in Onondaga Lake. Mussel methylmercury concentrations averaged 53% of THg concentrations but were highly variable. Strong relationships between water column THg and zebra mussel THg suggest that zebra mussels are a good indicator of aquatic mercury concentrations and could be used as an effective biomonitor of mercury contamination in aquatic ecosystems.

  2. Mitigation of unionid mortality caused by zebra mussel infestation: cleaning of unionids

    USGS Publications Warehouse

    Schloesser, Don W.

    1996-01-01

    Exotic zebra mussels Dreissena polymorpha have infested and caused mortality of native unionids in the Great Lakes since 1986; no other such parasitism of native unionids occurs in North America. Survival of unionids threatened by zebra mussel infestation was tested by suspending uncleaned and cleaned unionids in nearshore waters of western Lake Erie. Survival was determined, and newly settled zebra mussels were removed from clean unionids at eight intervals that ranged from 21 d to 77 d between 5 July 1990 and 3 July 1991. After 1 year, survival rates of uncleaned and cleaned unionids were 0% and 42%, respectively. Of the 10 species examined, only indivduals from 3 species (Amblema plicata plicata, Fusconaia flava, and Quadrula quadrula) survived 1 year. These species have relatively thick shells, which may have contributed to their survival. Removal of newly settled zebra mussels may be important to unionid survival because 98% of the zebra mussels removed after the initial cleaning were small mussels (<10 mm long) that could rapidly grow and cover unionids. At present, we do not know how zebra mussels cause mortality of unionids, but the removal of zebra mussels from unionids is the only method known that successfully reduces unionid mortality in waters colonized by zebra mussels.

  3. Magnetic fields, plasma densities, and plasma beta parameters estimated from high-frequency zebra fine structures

    NASA Astrophysics Data System (ADS)

    Karlický, M.; Jiricka, K.

    2002-10-01

    Using the recent model of the radio zebra fine structures (Ledenev et al. 2001) the magnetic fields, plasma densities, and plasma beta parameters are estimated from high-frequency zebra fine structures. It was found that in the flare radio source of high-frequency (1-2 GHz) zebras the densities and magnetic fields vary in the intervals of (1-4)×1010 cm-3 and 40-230 G, respectively. Assuming then the flare temperature as about of 107K, the plasma beta parameters in the zebra radio sources are in the 0.05-0.81 interval. Thus the plasma pressure effects in such radio sources, especially in those with many zebra lines, are not negligible.

  4. Bioaccumulation of pathogenic bacteria and amoeba by zebra mussels and their presence in watercourses.

    PubMed

    Mosteo, R; Goñi, P; Miguel, N; Abadías, J; Valero, P; Ormad, M P

    2016-01-01

    Dreissena polymorpha (the zebra mussel) has been invading freshwater bodies in Europe since the beginning of the nineteenth century. Filter-feeding organisms can accumulate and concentrate both chemical and biological contaminants in their tissues. Therefore, zebra mussels are recognized as indicators of freshwater quality. In this work, the capacity of the zebra mussel to accumulate human pathogenic bacteria and protozoa has been evaluated and the sanitary risk associated with their presence in surface water has also been assessed. The results show a good correlation between the pathogenic bacteria concentration in zebra mussels and in watercourses. Zebra mussels could therefore be used as an indicator of biological contamination. The bacteria (Escherichia coli, Enterococcus spp., Pseudomonas spp., and Salmonella spp.) and parasites (Cryptosporidium oocysts and free-living amoebae) detected in these mussels reflect a potential sanitary risk in water. PMID:26400243

  5. Bioaccumulation of pathogenic bacteria and amoeba by zebra mussels and their presence in watercourses.

    PubMed

    Mosteo, R; Goñi, P; Miguel, N; Abadías, J; Valero, P; Ormad, M P

    2016-01-01

    Dreissena polymorpha (the zebra mussel) has been invading freshwater bodies in Europe since the beginning of the nineteenth century. Filter-feeding organisms can accumulate and concentrate both chemical and biological contaminants in their tissues. Therefore, zebra mussels are recognized as indicators of freshwater quality. In this work, the capacity of the zebra mussel to accumulate human pathogenic bacteria and protozoa has been evaluated and the sanitary risk associated with their presence in surface water has also been assessed. The results show a good correlation between the pathogenic bacteria concentration in zebra mussels and in watercourses. Zebra mussels could therefore be used as an indicator of biological contamination. The bacteria (Escherichia coli, Enterococcus spp., Pseudomonas spp., and Salmonella spp.) and parasites (Cryptosporidium oocysts and free-living amoebae) detected in these mussels reflect a potential sanitary risk in water.

  6. Exploration of structure-antifouling relationships of capsaicin-like compounds that inhibit zebra mussel (Dreissena polymorpha) macrofouling.

    PubMed

    Angarano, Maj-Britt; McMahon, Robert F; Hawkins, Doyle L; Schetz, John A

    2007-01-01

    Macrofouling of aquatic man-made structures by zebra mussels (Dreissena polymorpha) poses significant economic burdens on commercial freshwater shipping and facilities utilising raw water. The negative environmental impact of some current antifouling technologies has limited their use and prompted investigation of non-organometallic and non-oxidising antifoulants as possible environment-friendly alternatives. The plant-derived natural product capsaicin and 18 other compounds with one or more capsaicin-like structural features were tested for their potential to inhibit zebra mussel byssal attachment at a single high concentration of 30 microM. Of these, three compounds displaying the highest levels of attachment inhibition where selected for further concentration-response testing. This testing revealed that capsaicin (8-methyl-N-vanillyl-trans-6-nonenamide), N-vanillylnonanamide, and N-benzoylmonoethanolamine benzoate all inhibited byssal attachment with potency values (EC(50)) in the micromolar range. None of these compounds were lethal to adult specimens of the water flea, Daphnia magna, at concentrations that inhibited mussel byssal attachment.

  7. Carotenoid-based plumage coloration predicts resistance to a novel parasite in the house finch

    NASA Astrophysics Data System (ADS)

    Hill, Geoffrey E.; Farmer, Kristy L.

    2005-01-01

    The Hamilton-Zuk hypothesis proposes that the bright colours displayed by many species of birds serve as signals of individual resistance to parasites. Despite the popularity of this hypothesis, only one previous study has tested whether plumage coloration predicts how individuals respond to a disease challenge. We inoculated 24 male house finches (Carpodacus mexicanus) of variable plumage hue with a novel bacterial pathogen, Mycoplasma gallicepticum (MG). We found no relationship between plumage hue and time to first symptoms following inoculation, but we found a significant negative relationship between plumage hue and clearance of disease: males with redder plumage cleared MG infection significantly better than did males with yellower plumage. The hue of carotenoid-based plumage coloration has been shown to be a primary criterion in female mate choice in the house finch. These observations suggest that one benefit to females for choosing redder males is obtaining mates with better resistance to parasites.

  8. Microlichus americanus acariasis in saffron finches (Sicalis flaveola) with dermatitis and feather loss.

    PubMed

    Rettenmund, Christy L; Ossiboff, Robert J; McAloose, Denise; Knee, Wayne; Wade, Susan E; Paré, Jean A

    2015-05-01

    Over a 5-year period, 13 saffron finches (Sicalis flaveola) housed in mixed aviaries at the Bronx Zoo (Bronx, New York) were examined with feather loss and dermatitis, primarily affecting the nape, neck, and dorsum. Feather loss, hyperkeratosis, epidermal hyperplasia, and mixed granulocytic and mononuclear inflammation were identified in biopsies from live birds and tissue sections from postmortem specimens. In 10 of 13 cases, sections of arthropod parasites were seen histologically within feather follicles and along the surface of affected skin. Based on morphological characteristics, mites recovered from samples of formalin-fixed skin in 4 birds were identified as Microlichus americanus, an epidermoptid mite infrequently reported from wild birds and hippoboscid flies. Gross and histological lesions strongly implicate M. americanus as the cause of dermatitis affecting practically all saffron finches in the collection.

  9. CINCH (confocal incoherent correlation holography) super resolution fluorescence microscopy based upon FINCH (Fresnel incoherent correlation holography)

    PubMed Central

    Siegel, Nisan; Storrie, Brian; Bruce, Marc

    2016-01-01

    FINCH holographic fluorescence microscopy creates high resolution super-resolved images with enhanced depth of focus. The simple addition of a real-time Nipkow disk confocal image scanner in a conjugate plane of this incoherent holographic system is shown to reduce the depth of focus, and the combination of both techniques provides a simple way to enhance the axial resolution of FINCH in a combined method called “CINCH”. An important feature of the combined system allows for the simultaneous real-time image capture of widefield and holographic images or confocal and confocal holographic images for ready comparison of each method on the exact same field of view. Additional GPU based complex deconvolution processing of the images further enhances resolution. PMID:26839443

  10. Peregrine falcon predation of endangered Laysan teal and Laysan Finches on remote Hawaiian atolls

    USGS Publications Warehouse

    Reynolds, Michelle H.; Nash, Sarah A.B.; Courtot, Karen

    2015-01-01

    We report the first records of Peregrine falcon (Falco peregrinus) predation on endangered Laysan teal (or duck; Anas laysanensis) and predation on endangered Laysan finches (Telespiza cantans). At Midway Atoll, vagrant Peregrine falcons killed ≥4% of a newly translocated Laysan teal population in 2006 and ≥2% in 2008. On Laysan Island during 2008–2009, remains of >76 Laysan finches (<1% of the population) were found at peregrine perches. On Midway Atoll, all depredated Laysan teal and other seabirds were recovered at kill sites on tarmac (runways). If the frequency or duration of vagrant raptors visitation increases at small atolls, this could pose a mortality risk to consider, especially during proposed translocations of endangered species. Vegetation restoration of abandoned runways near wetlands at Midway Atoll would provide cover and may help reduce mortality of endangered species due to vagrant raptors.

  11. Carotenoid-based plumage coloration predicts resistance to a novel parasite in the house finch.

    PubMed

    Hill, Geoffrey E; Farmer, Kristy L

    2005-01-01

    The Hamilton-Zuk hypothesis proposes that the bright colours displayed by many species of birds serve as signals of individual resistance to parasites. Despite the popularity of this hypothesis, only one previous study has tested whether plumage coloration predicts how individuals respond to a disease challenge. We inoculated 24 male house finches (Carpodacus mexicanus) of variable plumage hue with a novel bacterial pathogen, Mycoplasma gallicepticum (MG). We found no relationship between plumage hue and time to first symptoms following inoculation, but we found a significant negative relationship between plumage hue and clearance of disease: males with redder plumage cleared MG infection significantly better than did males with yellower plumage. The hue of carotenoid-based plumage coloration has been shown to be a primary criterion in female mate choice in the house finch. These observations suggest that one benefit to females for choosing redder males is obtaining mates with better resistance to parasites. PMID:15558224

  12. Pathology and immunohistochemistry of papillomavirus-associated cutaneous lesions in Cape mountain zebra, giraffe, sable antelope and African buffalo in South Africa.

    PubMed

    Williams, J H; van Dyk, E; Nel, P J; Lane, E; Van Wilpe, E; Bengis, R G; de Klerk-Lorist, L M; van Heerden, J

    2011-06-01

    Skin lesions associated with papillomaviruses have been reported in many animal species and man. Bovine papillomavirus (BVP) affects mainly the epidermis, but also the dermis in several species including bovine, the best-known example being equine sarcoid, which is associated with BVP types 1 and 2. This publication describes and illustrates the macroscopic and histological appearance of BPV-associated papillomatous, fibropapillomatous or sarcoid-like lesions in Cape mountain zebra (Equus zebra zebra) from the Gariep Dam Nature Reserve, 2 giraffes (Giraffa camelopardalis) from the Kruger National Park, and a sable antelope (Hippotragus niger) from the Kimberley area of South Africa. An African buffalo (Syncerus caffer) cow from Kruger National Park also had papillomatous lesions but molecular characterisation of lesional virus was not done. Immunohistochemical staining using polyclonal rabbit antiserum to chemically disrupted BPV-1, which cross-reacts with the L1 capsid of most known papillomaviruses, was positive in cells of the stratum granulosum of lesions in Giraffe 1, the sable and the buffalo and negative in those of the zebra and Giraffe 2. Fibropapillomatous and sarcoid-like lesions from an adult bovine were used as positive control for the immunohistochemistry and are described and the immunohistochemistry illustrated for comparison. Macroscopically, both adult female giraffe had severely thickened multifocal to coalescing nodular and occasionally ulcerated lesions of the head, neck and trunk with local poorly-circumscribed invasion into the subcutis. Necropsy performed on the 2nd giraffe revealed neither internal metastases nor serious underlying disease. Giraffe 1 had scattered, and Giraffe 2 numerous, large, anaplastic, at times indistinctly multinucleated dermal fibroblasts with bizarre nuclei within the sarcoid-like lesions, which were BPV-1 positive in Giraffe 1 and BPV-1 and -2 positive in Giraffe 2 by RT-PCR. The sable antelope presented with a

  13. On the Hypothetico-Deductive Nature of Science—Darwin's Finches

    NASA Astrophysics Data System (ADS)

    Lawson, Anton E.

    2009-01-01

    Allchin (2006) has misinterpreted a classic case of hypothetico-deductive (HD) science in terms of his preferred ‘let’s-gather-some-data-and-see-what-emerges’ view. The misrepresentation concerns the research program of Peter and Rosemary Grant on Darwin’s finches. The present essay argues that the Grants’ research is HD in nature and includes a statement by Peter Grant to that effect.

  14. Is the body condition of the invasive zebra mussel (Dreissena polymorpha) enhanced through attachment to native freshwater mussels (Bivalvia, Unionidae)?

    PubMed

    Pilotto, Francesca; Sousa, Ronaldo; Aldridge, David C

    2016-05-15

    The invasion of zebra mussels, Dreissena polymorpha, into Western Europe and North America has driven widespread ecological change. Attachment of zebra mussels to the shell of native unionoid mussels has resulted in reductions in unionoid abundance and, in extreme cases, their localised extirpations. While the impacts of zebra mussels on infested unionoids are well documented, the possible benefits of the association to the zebra mussel have been little considered. We collected zebra mussels attached to unionoids and to inanimate structures. Zebra mussels attached to unionoids had significantly larger shells, higher standardized body mass and glycogen content than those attached to inanimate substrates, suggesting that D. polymorpha benefits from settling upon unionoids. The body condition of individual zebra mussels was negatively correlated with the number of zebra mussels attached to the unionoid, indicating intraspecific competition. Therefore, zebra mussels seem positively affected through attachment to unionoid mussels, but that these benefits decrease at higher densities of fouling. This association may offer advantages to the spread of zebra mussels within unionoid-rich systems, especially at sites with soft substrates and at the early stages of the invasion process where intraspecific competition is likely to be lower and benefits to the zebra mussels are higher. PMID:26925735

  15. Is the body condition of the invasive zebra mussel (Dreissena polymorpha) enhanced through attachment to native freshwater mussels (Bivalvia, Unionidae)?

    PubMed

    Pilotto, Francesca; Sousa, Ronaldo; Aldridge, David C

    2016-05-15

    The invasion of zebra mussels, Dreissena polymorpha, into Western Europe and North America has driven widespread ecological change. Attachment of zebra mussels to the shell of native unionoid mussels has resulted in reductions in unionoid abundance and, in extreme cases, their localised extirpations. While the impacts of zebra mussels on infested unionoids are well documented, the possible benefits of the association to the zebra mussel have been little considered. We collected zebra mussels attached to unionoids and to inanimate structures. Zebra mussels attached to unionoids had significantly larger shells, higher standardized body mass and glycogen content than those attached to inanimate substrates, suggesting that D. polymorpha benefits from settling upon unionoids. The body condition of individual zebra mussels was negatively correlated with the number of zebra mussels attached to the unionoid, indicating intraspecific competition. Therefore, zebra mussels seem positively affected through attachment to unionoid mussels, but that these benefits decrease at higher densities of fouling. This association may offer advantages to the spread of zebra mussels within unionoid-rich systems, especially at sites with soft substrates and at the early stages of the invasion process where intraspecific competition is likely to be lower and benefits to the zebra mussels are higher.

  16. Detection of Equid herpesvirus 9 DNA in the trigeminal ganglia of a Burchell's zebra from the Serengeti ecosystem.

    PubMed

    Borchers, Kerstin; Lieckfeldt, Dietmar; Ludwig, Arne; Fukushi, Hideto; Allen, George; Fyumagwa, Robert; Hoare, Richard

    2008-12-01

    Equid herpesvirus 9 (EHV-9) was isolated from a herd of Thomson's gazelles affected by encephalitis. The natural host of EHV-9 is unknown, but zebras are suspected to be the source of infection in gazelles. To prove this hypothesis, we analyzed 43 sera from Burchell's zebras (Equus burchelli) and 21 Thomson's gazelles (Gazella thomsoni) from the Serengeti ecosystem for neutralizing antibodies. Seven zebra sera were positive for EHV-1, EHV-9 and EHV-1 from Grevy's zebra strains T965 and T616. The trigeminal ganglia of 17 other Burchell's zebras and one Thomson's gazelle were tested by EHV-9 gB and EHV-1 ICP0-specific nested polymerase chain reaction (PCR). PCR sequencing confirmed that one zebra ganglion was positive for EHV-9. These results suggest that the Burchell's zebras were exposed to EHV-9 and latently infected. PMID:19122410

  17. Detection of Equid herpesvirus 9 DNA in the trigeminal ganglia of a Burchell's zebra from the Serengeti ecosystem.

    PubMed

    Borchers, Kerstin; Lieckfeldt, Dietmar; Ludwig, Arne; Fukushi, Hideto; Allen, George; Fyumagwa, Robert; Hoare, Richard

    2008-12-01

    Equid herpesvirus 9 (EHV-9) was isolated from a herd of Thomson's gazelles affected by encephalitis. The natural host of EHV-9 is unknown, but zebras are suspected to be the source of infection in gazelles. To prove this hypothesis, we analyzed 43 sera from Burchell's zebras (Equus burchelli) and 21 Thomson's gazelles (Gazella thomsoni) from the Serengeti ecosystem for neutralizing antibodies. Seven zebra sera were positive for EHV-1, EHV-9 and EHV-1 from Grevy's zebra strains T965 and T616. The trigeminal ganglia of 17 other Burchell's zebras and one Thomson's gazelle were tested by EHV-9 gB and EHV-1 ICP0-specific nested polymerase chain reaction (PCR). PCR sequencing confirmed that one zebra ganglion was positive for EHV-9. These results suggest that the Burchell's zebras were exposed to EHV-9 and latently infected.

  18. The finch epidemic strain of Trichomonas gallinae is predominant in British non-passerines.

    PubMed

    Chi, Jean F; Lawson, Becki; Durrant, Chris; Beckmann, Katie; John, Shinto; Alrefaei, Abdulwahed F; Kirkbride, Kim; Bell, Diana J; Cunningham, Andrew A; Tyler, Kevin M

    2013-09-01

    Avian trichomonosis, caused by the flagellated protozoan Trichomonas gallinae, is a recently emerged infectious disease of British passerines. The aetiological agent, a clonal epidemic strain of the parasite, has caused unprecedented finch mortality and population-level declines in Britain and has since spread to continental Europe. To better understand the potential origin of this epidemic and to further investigate its host range, T. gallinae DNA extracts were collected from parasite culture and tissue samples from a range of avian species in Britain. Sequence typing at the ITS1/5.8S rRNA/ITS2 region resolved three distinct ITS region types circulating in free-ranging British birds. Subtyping by sequence analyses at the Fe-hydrogenase gene demonstrated further strain variation within these ITS region types. The UK finch epidemic strain was preponderant amongst columbids sampled, however, wide strain diversity was encountered in isolates from a relatively small number of pigeons, suggesting further strains present in columbid populations across the UK are yet to be identified. Fe-hydrogenase gene sequence data in isolates from birds of prey with disease were predominantly identical to the UK finch epidemic strain, demonstrating its presence as a virulent strain in UK birds of prey since at least 2009. PMID:23920088

  19. Structural tissue organization in the beak of Java and Darwin's finches

    PubMed Central

    Genbrugge, Annelies; Adriaens, Dominique; Kegel, Barbara; Brabant, Loes; Hoorebeke, Luc; Podos, Jeffrey; Dirckx, Joris; Aerts, Peter; Herrel, Anthony

    2012-01-01

    Birds are well known for occupying diverse feeding niches, and for having evolved diverse beak morphologies associated with dietary specialization. Birds that feed on hard seeds typically possess beaks that are both deep and wide, presumably because of selection for fracture avoidance, as suggested by prior studies. It follows then that birds that eat seeds of different size and hardness should vary in one or more aspects of beak morphology, including the histological organization of the rhamphotheca, the cellular interface that binds the rhamphotheca to the bone, and the organization of trabeculae in the beak. To explore this expectation we here investigate tissue organization in the rhamphotheca of the Java finch, a large granivorous bird, and describe interspecific differences in the trabecular organization of the beak across 11 species of Darwin's finches. We identify specializations in multiple layers of the horny beak, with the dermis anchored to the bone by Sharpey's fibers in those regions that are subjected to high stresses during biting. Moreover, the rhamphotheca is characterized by a tight dermo-epidermal junction through interdigitations of these two tissues. Herbst corpuscles are observed in high density in the dermis of the lateral aspect of the beak as observed in other birds. Finally, the trabecular organization of the beak in Darwin's finches appears most variable in regions involved most in food manipulation, with the density of trabeculae in the beak generally mirroring loading regimes imposed by different feeding habits and beak use in this clade. PMID:22938039

  20. Rates of karyotypic evolution in Estrildid finches differ between island and continental clades.

    PubMed

    Hooper, Daniel M; Price, Trevor D

    2015-04-01

    Reasons why chromosomal rearrangements spread to fixation and frequently distinguish related taxa remain poorly understood. We used cytological descriptions of karyotype to identify large pericentric inversions between species of Estrildid finches (family Estrildidae) and a time-dated phylogeny to assess the genomic, geographic, and phylogenetic context of karyotype evolution in this group. Inversions between finch species fixed at an average rate of one every 2.26 My. Inversions were twice as likely to fix on the sex chromosomes compared to the autosomes. A high repeat density on the sex chromosomes may increase mutation rates, but other explanations via mutagenic input are not supported, as the number of inversions on a chromosome does not correlate with its length or map size. Inversions have fixed 3.3× faster in three continental clades than in two island chain clades, and fixation rate correlates with both range size and the number of sympatric species pairs. These results point to adaptation as the dominant mechanism driving fixation and suggest a role for gene flow in karyotype divergence. A review shows that the rapid karyotype evolution observed in the Estrildid finches appears to be more general across birds, and by implication other understudied taxa.

  1. DIVERSITY OF FEATHER MITES (ACARI: ASTIGMATA) ON DARWIN’S FINCHES

    PubMed Central

    Villa, Scott M.; Le Bohec, Céline; Koop, Jennifer A. H.; Proctor, Heather C.; Clayton, Dale H.

    2014-01-01

    Feather mites are a diverse group of ectosymbionts that occur on most species of birds. Although Darwin’s finches are a well-studied group of birds, relatively little is known about their feather mites. Nearly 200 birds across 9 finch species, and from 2 locations on Santa Cruz Island, Galápagos, were dust-ruffled during the 2009 breeding season. We found 8 genera of feather mites; the most prevalent genus was Mesalgoides (53–55%), followed by Trouessartia (40–45%), Amerodectes and Proctophyllodes (26–33%), Xolalgoides (21–27%), Analges and Strelkoviacarus (0–6%), and Dermoglyphus (2–4%). There was no evidence for microclimatic effects (ambient temperature and relative humidity) on mite diversity. Host body mass was significantly correlated with mean feather mite abundance across 7 of 8 well-sampled species of finches. Certhidea olivacea, the smallest species, did not fit this pattern and had a disproportionately high number of mites for its body mass. PMID:23691947

  2. Spike-like Bursts as Fine Structure of Zebras

    NASA Astrophysics Data System (ADS)

    Zlobec, P.; Karlický, M.

    2007-12-01

    We studied the characteristics of the zebra-associated spike-like bursts that were recorded with high time resolution at 1420 MHz in four intervals (from 12:45 to 12:48 UT) during 5 August 2003. Our detailed analysis is based on the selection of more than 500 such spike-like bursts and it is, at least to our knowledge, the first study devoted to such short-lived bursts. Their characteristics are different from those pertinent to “normal” spike bursts, as presented in the paper by Güdel and Benz ( Astron. Astrophys. 231, 202, 1990); in particular, their duration (about 7.4 ms at half power) is shorter, so they should be members of the SSS (super short structures) family (Magdalenić et al., Astrophys. J. 642, L77, 2006). The bursts were generally strongly R-polarized; however, during the decaying part of interval I a low R-polarized and L-polarized bursts were also present. This change of polarization shows a trend that resembles the peculiar form of the zebra lines in the spectral dominion (“V” like). A global statistical analysis on the bursts observed in the two polarimetric channels shows that the highest cross-correlation coefficient (about 0.5) was pertinent to interval I. The zebras and the bursts can be interpreted by the same double plasma resonance process as proposed by Bárta and Karlický ( Astron. Astrophys. 379, 1045, 2001) and Karlický et al. ( Astron. Astrophys. 375, 638, 2001); in particular, the spikes are generated by the interruption of this process by assumed turbulence (density or magnetic field variations). This process should be present in the region close to the reconnection site ( e.g., in the plasma reconnection outflows) where the density and the magnetic field vary strongly.

  3. The effect of sodium chlorite solutions on zebra mussel mortality

    SciTech Connect

    Dion, J.; Richer, Y.; Messer, R.

    1995-06-01

    The effect of four dilutions, 8 ppm, 40 ppm, 120 ppm and 473 ppm of the stock solution of a first product, Z-8, on zebra mussel mortality was investigated in static continuous exposure systems and compared to controls. The entire size class spectrum of the mussel population present at the sampling site was tested by leaving mussels attached to their original rock substrata. Two size class grouping of mussels, 13 mm and less and more than 13 mm in length, were exposed in the same test chambers but were analyzed separately. No mortality occurred in the controls. Concentration 8 ppm had no effect after 166 hours on both size class groupings. Concentrations 40, 120 and 473 ppm had observable killing effect within the 331 hours of experiment for both size groupings. The smaller mussels died faster than the larger ones. Another product, Z-11, was similarly tested during fall 1994 with dilutions 8, 40, 80 and 120 ppm. At 8 ppm dilution, Z-11 had induced only little mortality on both size class groupings after 739 hours. At 40, 80 and 120 ppm dilutions, Z-11 had interesting killing effect for both mussel size groupings within the 739 hours of experiment considering the somehow intermittent treatment used. The results already appear to show that sodium chlorite solutions have the potential for eventually becoming a surrogate to the use of chlorine for the control of zebra mussels. That is because they already show a good killing efficiency without being involved in the formation of undesired by-products such as the use of chlorine is. On this purpose, the product is engaged in the process of homologation by Agriculture Canada for it use as treatment against zebra mussels.

  4. Zebra mussel control using thermal treatment for electric utility stations

    SciTech Connect

    Marcus, R.I.; Wahlert, S.L.

    1995-10-01

    When electric utilities and other water users on the Great Lakes were confronted with operating problems due to zebra mussels, Commonwealth Edison Company (ComEd) established a task force to develop a plan to counteract the threat at the ComEd electric generating stations. A monitoring program was initiated at the stations, and an evaluation of control options was started. At State Line Station, located on the southern tip of Lake Michigan, ComEd experimented with thermal treatment of the circulating water and service water systems. The station design allows recirculation of the cooling water with minimal modifications. The trial at State Line Station proved successful in controlling the zebra mussels with minimal impact on operations. Based on the successful trial and the task force`s assessment of other control options, ComEd determined that, for their fossil-fueled generating stations, thermal treatment was the most cost-effective approach, with the least impact on station operation and the environment. Of the 10 fossil-fueled generating stations operated by ComEd, 8 have been selected for modifications. The other 2 stations have not yet been affected by zebra mussels. Before performing detailed design, a study was performed for each station to evaluate the operation of the equipment at elevated temperature and to determine the operating limits needed at the target treatment temperature of 95 F. Conceptual designs for the modifications were developed, and the most cost-effective arrangement was selected for detailed design. Case studies of the modifications being constructed at several stations are presented. The modifications to the circulating water systems are described. Initial results of the treatment are reviewed.

  5. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    SciTech Connect

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  6. Social Memory Formation Rapidly and Differentially Affects the Motivation and Performance of Vocal Communication Signals in the Bengalese Finch (Lonchura striata var. domestica).

    PubMed

    Toccalino, Danielle C; Sun, Herie; Sakata, Jon T

    2016-01-01

    Cognitive processes like the formation of social memories can shape the nature of social interactions between conspecifics. Male songbirds use vocal signals during courtship interactions with females, but the degree to which social memory and familiarity influences the likelihood and structure of male courtship song remains largely unknown. Using a habituation-dishabituation paradigm, we found that a single, brief (<30 s) exposure to a female led to the formation of a short-term memory for that female: adult male Bengalese finches were significantly less likely to produce courtship song to an individual female when re-exposed to her 5 min later (i.e., habituation). Familiarity also rapidly decreased the duration of courtship songs but did not affect other measures of song performance (e.g., song tempo and the stereotypy of syllable structure and sequencing). Consistent with a contribution of social memory to the decrease in courtship song with repeated exposures to the same female, the likelihood that male Bengalese finches produced courtship song increased when they were exposed to a different female (i.e., dishabituation). Three consecutive exposures to individual females also led to the formation of a longer-term memory that persisted over days. Specifically, when courtship song production was assessed 2 days after initial exposures to females, males produced fewer and shorter courtship songs to familiar females than to unfamiliar females. Measures of song performance, however, were not different between courtship songs produced to familiar and unfamiliar females. The formation of a longer-term memory for individual females seemed to require at least three exposures because males did not differentially produce courtship song to unfamiliar females and females that they had been exposed to only once or twice. Taken together, these data indicate that brief exposures to individual females led to the rapid formation and persistence of social memories and support the

  7. Social Memory Formation Rapidly and Differentially Affects the Motivation and Performance of Vocal Communication Signals in the Bengalese Finch (Lonchura striata var. domestica)

    PubMed Central

    Toccalino, Danielle C.; Sun, Herie; Sakata, Jon T.

    2016-01-01

    Cognitive processes like the formation of social memories can shape the nature of social interactions between conspecifics. Male songbirds use vocal signals during courtship interactions with females, but the degree to which social memory and familiarity influences the likelihood and structure of male courtship song remains largely unknown. Using a habituation-dishabituation paradigm, we found that a single, brief (<30 s) exposure to a female led to the formation of a short-term memory for that female: adult male Bengalese finches were significantly less likely to produce courtship song to an individual female when re-exposed to her 5 min later (i.e., habituation). Familiarity also rapidly decreased the duration of courtship songs but did not affect other measures of song performance (e.g., song tempo and the stereotypy of syllable structure and sequencing). Consistent with a contribution of social memory to the decrease in courtship song with repeated exposures to the same female, the likelihood that male Bengalese finches produced courtship song increased when they were exposed to a different female (i.e., dishabituation). Three consecutive exposures to individual females also led to the formation of a longer-term memory that persisted over days. Specifically, when courtship song production was assessed 2 days after initial exposures to females, males produced fewer and shorter courtship songs to familiar females than to unfamiliar females. Measures of song performance, however, were not different between courtship songs produced to familiar and unfamiliar females. The formation of a longer-term memory for individual females seemed to require at least three exposures because males did not differentially produce courtship song to unfamiliar females and females that they had been exposed to only once or twice. Taken together, these data indicate that brief exposures to individual females led to the rapid formation and persistence of social memories and support the

  8. Structure and evolution of electron "zebra stripes" in the inner radiation belt

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Zong, Q.-G.; Zhou, X.-Z.; Foster, J. C.; Rankin, R.

    2016-05-01

    "Zebra stripes" are newly found energetic electron energy-spatial (L shell) distributed structure with an energy between tens to a few hundreds keV in the inner radiation belt. Using high-quality measurements of electron fluxes from Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE) on board the twin Van Allen Probes, we carry out case and statistical studies from April 2013 to April 2014 to study the structural and evolutionary characteristics of zebra stripes below L = 3. It is revealed that the zebra stripes can be transformed into evenly spaced patterns in the electron drift frequency coordinate: the detrended logarithmic fluxes in each L shell region can be well described by sinusoidal functions of drift frequency. The "wave number" of this sinusoidal function, which corresponds to the reciprocal of the gap between two adjacent peaks in the drift frequency coordinate, increases in proportion to real time. Further, these structural and evolutionary characteristics of zebra stripes can be reproduced by an analytic model of the evolution of the particle distribution under a single monochromatic or static azimuthal electric field. It is shown that the essential ingredient for the formation of multiple zebra stripes is the periodic drift of particles. The amplitude of the zebra stripes shows a good positive correlation with Kp index, which indicates that the generation mechanism of zebra stripes should be related to geomagnetic activities.

  9. Food habits of diving ducks in the Great Lakes after the zebra mussel invasion

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.

    1996-01-01

    Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Common Goldeneyes (B. clangula) were collected in western Lake Erie and in Lake St. Clair between fall and spring, 1992-1993 to determine food habits. All 10 Redheads, 97% of Lesser Scaups, 83% of Goldeneyes, 60% of Buffleheads and 9% of Canvasbacks contained one or more zebra mussels in their upper gastrointestinal tracts. The aggregate percent of zebra mussels in the diet of Lesser Scaups was higher in Lake Erie (98.6%) than in Lake St. Clair (54.4%). Zebra mussels (aggregate percent) dominated the diet of Common Goldeneyes (79.2%) but not in Buffleheads (23.5%), Redheads (21%) or Canvasbacks (9%). Lesser Scaups from Lake Erie fed on larger zebra mussels ( = 10.7 i?? 0.66 mm SE) than did Lesser Scaups from Lake St. Clair ( = 4.4 i?? 0.22 mm). Lesser Scaups, Buffleheads and Common Goldeneyes from Lake Erie consumed zebra mussels of similar size.

  10. Occurrence of zebra mussels in near-shore areas of western Lake Erie

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.

    1997-01-01

    Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Common Goldeneyes (B. clangula) were collected in western Lake Erie and in Lake St. Clair between fall and spring, 1992-1993 to determine food habits. All 10 Redheads, 97% of Lesser Scaups, 83% of Goldeneyes, 60% of Buffleheads and 9% of Canvasbacks contained one or more zebra mussels in their upper gastrointestinal tracts. The aggregate percent of zebra mussels in the diet of Lesser Scaups was higher in Lake Erie (98.6%) than in Lake St. Clair (54.4%). Zebra mussels, (aggregate percent) dominated the diet of Common Goldeneyes (79.2%) but not in Buffleheads (23.5%), Redheads (21%) or Canvasbacks (9%). Lesser Scaups from Lake Erie fed on larger zebra mussels ( = 10.7 i?? 0.66 mm SE) than did Lesser Scaups from Lake St. Clair ( = 4.4 i?? 0.22 mm). Lesser Scaups, Buffleheads and Common Goldeneyes from Lake Erie consumed zebra mussels of similar size.

  11. Predation of the zebra mussel (Dreissena polymorpha) by freshwater drum in western Lake Erie

    USGS Publications Warehouse

    French, John R. P.; Bur, Michael T.; Nalepa, Thomas F.; Schloesser, Donald W.

    1992-01-01

    Environmental and economic problems associated with the colonization of zebra mussels (Dreissena polymorpha) in western Lake Erie created a need to investigate control mechanisms. Predation by fishes is one potential means of control, but predation on zebra mussels by native fishes in Lake Erie is unknown. The freshwater drum (Aplodinotus grunniens) is the most likely fish predator since it is the only fish with pharyngeal teeth capable of crushing mollusk shells. In 1990, freshwater drum were collected in western Lake Erie from 9 sites near rocky reefs and 13 sites with silt or sand bottoms, and gut contents were examined. Predation on zebra mussels increased as drum size increased. Small drum (200-249 mm in length) fed mainly on dipterans, amphipods, and small fish; small zebra mussels (375 mm in length) fed almost exclusively on zebra mussels (seasons and locations combined). The smallest drum capable of crushing zebra mussel shells was 265 mm. Since freshwater drum over 375 mm feed heavily on zebra mussels, they may become a possible biological control mechanism for mussels in portions of North America.

  12. Zebra mussels affect benthic predator foraging success and habitat choice on soft sediments.

    PubMed

    Beekey, M A; McCabe, D J; Marsden, J E

    2004-09-01

    The introduction of zebra mussels ( Dreissena spp.) to North America has resulted in dramatic changes to the complexity of benthic habitats. Changes in habitat complexity may have profound effects on predator-prey interactions in aquatic communities. Increased habitat complexity may affect prey and predator dynamics by reducing encounter rates and foraging success. Zebra mussels form thick contiguous colonies on both hard and soft substrates. While the colonization of substrata by zebra mussels has generally resulted in an increase in both the abundance and diversity of benthic invertebrate communities, it is not well known how these changes affect the foraging efficiencies of predators that prey on benthic invertebrates. We examined the effect of zebra mussels on the foraging success of four benthic predators with diverse prey-detection modalities that commonly forage in soft substrates: slimy sculpin ( Cottus cognatus), brown bullhead ( Ameirus nebulosus), log perch ( Percina caprodes), and crayfish ( Orconectes propinquus). We conducted laboratory experiments to assess the impact of zebra mussels on the foraging success of predators using a variety of prey species. We also examined habitat use by each predator over different time periods. Zebra mussel colonization of soft sediments significantly reduced the foraging efficiencies of all predators. However, the effect was dependent upon prey type. All four predators spent more time in zebra mussel habitat than in either gravel or bare sand. The overall effect of zebra mussels on benthic-feeding fishes is likely to involve a trade-off between the advantages of increased density of some prey types balanced against the reduction in foraging success resulting from potential refugia offered in the complex habitat created by zebra mussels.

  13. Zebra mussels anchor byssal threads faster and tighter than quagga mussels in flow.

    PubMed

    Peyer, Suzanne M; McCarthy, Alice J; Lee, Carol Eunmi

    2009-07-01

    While the invasive zebra mussel Dreissena polymorpha has rapidly spread throughout the Great Lakes and inland waterways, it is being displaced by the quagga mussel Dreissena bugensis in shallow water habitats. However, zebra mussels remain dominant in areas with higher water velocity. We hypothesized that the persistence of zebra over quagga mussels in habitats with higher water velocity might result from greater rate and strength of byssal thread attachment. We examined whether zebra mussels relative to quagga mussels have: (1) higher byssal thread synthesis rate, (2) lower dislodgment in flow and (3) greater mechanical force required for detachment from substrate. Specifically, we examined byssal thread synthesis rate and dislodgment of both species in response to water velocities of 0, 50, 100 and 180 cm s(-1). Byssal thread synthesis rate was significantly higher for zebra than for quagga mussels at all velocities. Dislodgment from the substrate increased for both species with increasing velocity but was significantly lower for zebra than for quagga mussels. We also tested the mechanical force to detach mussels after short (32 h) and long (two and three months) periods of attachment on hard substrate. Detachment force was significantly higher for zebra than for quagga mussels only after short-term attachment. Higher byssal thread synthesis rate in zebra mussels was a likely factor that minimized their dislodgment in flow and increased short-term attachment strength. Differences in byssal thread synthesis rate between the two species might partly account for the ability of zebra mussels to maintain dominance over quagga mussels in habitats with high velocities.

  14. Economic impacts of zebra mussels on drinking water treatment and electric power generation facilities.

    PubMed

    Connelly, Nancy A; O'Neill, Charles R; Knuth, Barbara A; Brown, Tommy L

    2007-07-01

    Invasions of nonnative species such as zebra mussels can have both ecological and economic consequences. The economic impacts of zebra mussels have not been examined in detail since the mid-1990s. The purpose of this study was to quantify the annual and cumulative economic impact of zebra mussels on surface water-dependent drinking water treatment and electric power generation facilities (where previous research indicated the greatest impacts). The study time frame was from the first full year after discovery in North America (Lake St. Clair, 1989) to the present (2004); the study area was throughout the mussels' North American range. A mail survey resulted in a response rate of 31% for electric power companies and 41% for drinking water treatment plants. Telephone interviews with a sample of nonrespondents assessed nonresponse bias; only one difference was found and adjusted for. Over one-third (37%) of surveyed facilities reported finding zebra mussels in the facility and almost half (45%) have initiated preventive measures to prevent zebra mussels from entering the facility operations. Almost all surveyed facilities (91%) with zebra mussels have used control or mitigation alternatives to remove or control zebra mussels. We estimated that 36% of surveyed facilities experienced an economic impact. Expanding the sample to the population of the study area, we estimated 267 million dollars (BCa 95% CI = 161 million dollars - 467 million dollars) in total economic costs for electric generation and water treatment facilities through late 2004, since 1989. Annual costs were greater (44,000 dollars/facility) during the early years of zebra mussel infestation than in recent years (30,000 dollars). As a result of this and other factors, early predictions of the ultimate costs of the zebra mussel invasion may have been excessive.

  15. Habitat selection and ecological speciation in Galápagos warbler finches (Certhidea olivacea and Certhidea fusca)

    PubMed Central

    Tonnis, Brandon; Grant, Peter R; Grant, B. Rosemary; Petren, Kenneth

    2005-01-01

    We investigated phylogeographic divergence among populations of Galápagos warbler finches. Their broad distribution, lack of phenotypic differentiation and low levels of genetic divergence make warbler finches an appropriate model to study speciation in allopatry. A positive relationship between genetic and geographical distances is expected for island taxa. Warbler finches actually showed a negative isolation by distance relationship, causing us to reject the hypothesis of distance‐limited dispersal. An alternative hypothesis, that dispersal is limited by habitat similarity, was supported. We found a positive correlation between genetic distances and differences in maximum elevation among islands, which is an indicator of ecological similarity. MtDNA sequence variation revealed monophyletic support for two distinct species. Certhidea olivacea have recently dispersed among larger central islands, while some Certhidea fusca have recently dispersed to small islands at opposite ends of the archipelago. We conclude that females have chosen to breed on islands with habitats similar to their natal environment. Habitat selection is implicated as an important component of speciation of warbler finches, which is the earliest known divergence of the adaptive radiation of Darwin's finches. These results suggest that small populations can harbour cryptic but biologically meaningful variation that may affect longer term evolutionary processes. PMID:15940826

  16. House Finch (Haemorhous mexicanus) Conjunctivitis, and Mycoplasma spp. Isolated from North American Wild Birds, 1994-2015.

    PubMed

    Ley, David H; Hawley, Dana M; Geary, Steven J; Dhondt, André A

    2016-07-01

    Sampling wild birds for mycoplasma culture has been key to the study of House Finch (Haemorhous mexicanus) conjunctivitis, yielding isolates of Mycoplasma gallisepticum spanning the temporal and geographic ranges of disease from emergence to endemicity. Faced with the challenges and costs of sample collection over time and from remote locations for submission to our laboratory for mycoplasma culture, protocols evolved to achieve a practical optimum. Herein we report making M. gallisepticum isolates from House Finches almost every year since the disease emerged in 1994, and we now have 227 isolates from 17 states. Our wild bird host range for M. gallisepticum isolates includes Blue Jay ( Cyanocitta cristata ), American Goldfinch (Spinus tristis), Lesser Goldfinch (Spinus psaltria), Purple Finch (Haemorhous purpureus), Evening Grosbeak ( Coccothraustes vespertinus ), and herein first reports for Western Scrub-jay ( Aphelocoma californica ), and American Crow ( Corvus brachyrhynchos ). By collecting and identifying isolates from birds with clinical signs similar to those of House Finch conjunctivitis, we also expanded the known host range of Mycoplasma sturni and obtained isolates from additional wild bird species. Accumulating evidence shows that a diverse range of wild bird species may carry or have been exposed to M. gallisepticum in the US, as in Europe and Asia. Therefore, the emergence of a pathogenic M. gallisepticum strain in House Finches may actually be the exception that has allowed us to identify the broader epidemiologic picture.

  17. House Finch (Haemorhous mexicanus) Conjunctivitis, and Mycoplasma spp. Isolated from North American Wild Birds, 1994-2015.

    PubMed

    Ley, David H; Hawley, Dana M; Geary, Steven J; Dhondt, André A

    2016-07-01

    Sampling wild birds for mycoplasma culture has been key to the study of House Finch (Haemorhous mexicanus) conjunctivitis, yielding isolates of Mycoplasma gallisepticum spanning the temporal and geographic ranges of disease from emergence to endemicity. Faced with the challenges and costs of sample collection over time and from remote locations for submission to our laboratory for mycoplasma culture, protocols evolved to achieve a practical optimum. Herein we report making M. gallisepticum isolates from House Finches almost every year since the disease emerged in 1994, and we now have 227 isolates from 17 states. Our wild bird host range for M. gallisepticum isolates includes Blue Jay ( Cyanocitta cristata ), American Goldfinch (Spinus tristis), Lesser Goldfinch (Spinus psaltria), Purple Finch (Haemorhous purpureus), Evening Grosbeak ( Coccothraustes vespertinus ), and herein first reports for Western Scrub-jay ( Aphelocoma californica ), and American Crow ( Corvus brachyrhynchos ). By collecting and identifying isolates from birds with clinical signs similar to those of House Finch conjunctivitis, we also expanded the known host range of Mycoplasma sturni and obtained isolates from additional wild bird species. Accumulating evidence shows that a diverse range of wild bird species may carry or have been exposed to M. gallisepticum in the US, as in Europe and Asia. Therefore, the emergence of a pathogenic M. gallisepticum strain in House Finches may actually be the exception that has allowed us to identify the broader epidemiologic picture. PMID:27285414

  18. Byssal proteins of the freshwater zebra mussel, Dreissena polymorpha.

    PubMed

    Gantayet, Arpita; Ohana, Lily; Sone, Eli D

    2013-01-01

    The freshwater zebra mussel (Dreissena polymorpha) is a notorious biofouling organism. It adheres to a variety of substrata underwater by means of a proteinaceous structure called the byssus, which consists of a number of threads with adhesive plaques at the tips. The byssal proteins are difficult to characterize due to extensive cross-linking of 3,4-dihydroxyphenylalanine (DOPA), which renders the mature structure largely resistant to protein extraction and immunolocalization. By inducing secretion of fresh threads and plaques in which cross-linking is minimized, three novel zebra mussel byssal proteins were identified following extraction and separation by gel electrophoresis. Peptide fragment fingerprinting was used to match tryptic digests of several gel bands against a cDNA library of genes expressed uniquely in the mussel foot, the organ which secretes the byssus. This allowed identification of a more complete sequence of Dpfp2 (D. polymorpha foot protein 2), a known DOPA-containing byssal protein, and a partial sequence of Dpfp5, a novel protein with several typical characteristics of mussel adhesive proteins. PMID:23211030

  19. Pseudodiarrhoea in zebra mussels Dreissena polymorpha (Pallas) exposed to microcystins.

    PubMed

    Juhel, Guillaume; Davenport, John; O'Halloran, John; Culloty, Sarah; Ramsay, Ruth; James, Kevin; Furey, Ambrose; Allis, Orla

    2006-03-01

    Microcystins are produced by bloom-forming cyanobacteria and pose significant health and ecological problems. In this study we show that zebra mussels respond differently to different strains of Microcystis aeruginosa, and that a highly toxic strain causes zebra mussels to produce large quantities of mucous pseudofaeces, 'pseudodiarrhoea', that are periodically expelled hydraulically through the pedal gape by shell valve adductions rather than by the normal ciliary tracts. Analysis of the pseudofaecal ejecta showed that the proportion of Microcystis aeruginosa relative to Asterionella formosa was high in the pseudofaeces and even higher in the 'pseudodiarrhoea' when a mixed diet was given to the mussels. This confirms that very toxic Microcystis aeruginosa were preferentially being rejected by comparison with the non-toxic diatom in the pseudofaeces and even more so in the 'pseudodiarrhoea'. Such selective rejection was not observed with low or non-toxic strains and would therefore tend to enhance the presence of toxic Microcystis aeruginosa in mixed Microcystis aeruginosa cyanobacterial blooms, as well as transferring toxins from the water column to the benthos. The observed acute irritant response to the toxin represents the first demonstration of an adverse sublethal effect of microcystins on invertebrate ecophysiology. Our results also suggest that it could be a specific response to microcystin-LF, a little studied toxin variant.

  20. Using zebra mussels to monitor Escherichia coli in environmental waters.

    PubMed

    Selegean, J P; Kusserow, R; Patel, R; Heidtke, T M; Ram, J L

    2001-01-01

    Use of the zebra mussel (Dreissena polymorpha) as an indicator of previously elevated bacteria concentrations in a watershed was examined. The ability of the zebra mussel to accumulate and purge Escherichia coli over several days was investigated in both laboratory and field experiments. In laboratory experiments, periodic enumeration of E. coli in mussels that had been exposed to a dilute solution of raw sewage demonstrated that (i) maximum concentrations of E. coli are reached within a few hours of exposure to sewage, (ii) the tissue concentration attained is higher than the concentration in the ambient water, and (iii) the E. coli concentrations take several days to return to preexposure concentrations when mussels are subsequently placed in sterile water. In field experiments conducted in southeast Michigan in the Clinton River watershed, brief increases in E. coli concentrations in the water were accompanied by increases in mussel concentrations of E. coli that lasted 2 or 3 d. The ability of mussels to retain and to concentrate E. coli made it possible to detect E. coli in the environment under conditions that conventional monitoring may often miss. Sampling caged mussels in a river and its tributaries may enable watershed managers to reduce the sampling frequency normally required to identify critical E. coli sources, thereby providing a more cost-effective river monitoring strategy for bacterial contamination.

  1. Zebra mussel control using periodic chlorine dioxide treatments. Final report

    SciTech Connect

    Mussalli, Y.G.; Martin, P.D.

    1995-11-01

    Chlorine dioxide was injected into the water intakes at two power plants in Illinois and one in Indiana in an effort to eradicate the existing population of zebra mussels and mitigate further settlement in station river water cooling systems. Results of the treatments at Illinois Power Company`s Wood River Station on the Mississippi River, Central Illinois Public Service`s Meredosia Station on the Illinois River, and SI Energy`s Gallagher Station on the Ohio River are reported. Treatments were performed on a turnkey basis, with three treatments performed at Meredosia Station in 1994, six treatments performed at Wood River Station between July 1993 and September 1994, and 2 treatments performed at Gallagher Station in 1994. For each treatment, a contractor installed and operated a portable chlorine dioxide generator, monitored water quality and oxidant levels, and provided and monitored bioboxes containing test mussels. Results of the treatments were very favorable, indicating a good potential for periodic treatments with chlorine dioxide to control zebra mussel infestations in the raw water systems of power plants and other industrial facilities. Some difficulties with the chlorine dioxide generation system and cold temperature effects reduced the treatment effectiveness, particularly the second treatment at Gallagher Station. Average induced mortalities ranged from 70 to 100% at Wood River, 87 to 92% at Meredosia, and 30 to 100% at Gallagher for native mussels. Dechlorination successfully kept total oxidant residual levels at or below 0.05 ppM during all treatments at all stations.

  2. A note on motor laterality in plains zebras (Equus burchellii) and impalas (Aepyceros melampus).

    PubMed

    McGreevy, P D; Landrieu, J-P; Malou, P F J

    2007-09-01

    This observational field study used intermittent still photography to examine the distribution of motor laterality in images of two African grazing quadruped species: plains zebras (Equus burchellii) and impalas (Aepyceros melampus). Zebra images (n=708) had a laterality index of -6.21 and a Z-score of -1.65 (p=.098). Impala images (n=318) had a laterality index of -18.87 and a Z-score of -3.36 (p=.0008). The weak left motor bias in zebras aligns with that reported in domestic horses using a related method.

  3. Longitudinal patterns in abundance of the zebra mussel (Dreissena polymorpha) in the upper Mississippi River

    USGS Publications Warehouse

    Cope, W.G.; Bartsch, M.R.; Hayden, R.R.

    1997-01-01

    We assessed the abundance of zebra mussels in the upper Mississippi River during 1995, four years after they were first found in the river. Samplers were deployed from May 30 to October 19, 1995, at 19 lock and dam facilities in the upper Mississippi River from Minneapolis, Minnesota, to Muscatine, Iowa. Zebra mussels were found at every lock and dam except the two sites farthest upstream (Minneapolis). Generally, densities of zebra mussels were greatest at sites 161 km and farther downstream of the Minneapolis area. The greatest mean mussel density was 11,432/m(2) at Fulton, Illinois.

  4. Experimental infection of zebra mussels Dreissena polymorpha (Mollusca:Bivalvia) by metacercariae of Echinoparyphium sp. (Platyhelminthes:Trematoda).

    PubMed

    Conn, D B; Conn, D A

    1995-04-01

    The zebra mussel Dreissena polymorpha a species recently introduced to North America from Europe, was studied to determine whether it could potentially serve as host for echinostomatid metacercariae. Forty adult mussels were collected from the St. Lawrence River and exposed to cercariae of Echinoparyphium sp. that was emerging from naturally infected Physa sp. collected from a native population in northern New York state. When necropsied 24-30 hr postexposure, 2 (5%) of the 40 harbored a metacercaria of Echinoparyphium sp. in the gonad. None of 200 control mussels collected from the same site was infected. This is the first report of any species or stage of echinostomatid from this host species worldwide. This is also the first report of an echinostomatid metacercaria from the gonad of any host species.

  5. Co-existence of zebra mussels and freshwater unionids: Population dynamics of Leptodea fragilis in a coastal wetland infested with zebra mussels

    USGS Publications Warehouse

    Nichols, S. Jerrine; Amberg, Jon

    1999-01-01

    In 1996, thousands of live Leptodea fragilis were collected from a marsh located in the western basin of Lake Erie that was infested with zebra mussels (Dreissena polymorpha). Despite the presence of zebra mussels at this site for a number of years, this L. fragilis population showed no signs of competition-induced changes in population dynamics. Biofouling was limited: fewer than 1% of the L. fragilis showed evidence of recent or past zebra mussel colonization. Successful recruitment occurred yearly, with multiple year classes collected that ranged in age from 1 to 12 years. However, age and shell length were not well correlated. Seventy-one percent of the individuals collected were 51-80 mm long, but ranged in age from 2 to 4.5 years. Three different patterns of growth or shell deposition were found. Some individuals grew rapidly, reaching 105 mm in 3.5 years, while others grew only 4.5 mm over the same time period. A few grew poorly during some years but very rapidly in others. Individuals with a shell length of 41 mm or more were sexually mature and females were more common than males. The strong recruitment and steady growth of this population showed no change between the years before and after the zebra mussel invasion, indicating that this marsh is functioning as a natural refugium from potential problems caused by zebra mussels.

  6. Illustrated identification keys to strongylid parasites (Strongylidae: Nematoda) of horses, zebras and asses (Equidae).

    PubMed

    Lichtenfels, J Ralph; Kharchenko, Vitaliy A; Dvojnos, Grigory M

    2008-09-15

    The Equidae (the horse, Equus caballus, the ass, Equus asinus, zebras and their hybrids) are hosts to a great variety of nematode parasites, some of which can cause significant morbidity or mortality if individual hosts are untreated. Worldwide the nematode parasites of horses belong to 7 suborders, 12 families, 29 genera and 83 species. The great majority (19 of 29 genera and 64 of 83 species) are members of the family Strongylidae, which includes the most common and pathogenic nematode parasites of horses. Only the Strongylidae are included in this treatise. The Strongylidae (common name strongylids) of horses--nematodes with a well-developed buccal capsule, a mouth collar with two leaf-crowns, and a strongyloid (common name of superfamily Strongyloidea) copulatory bursa--can be separated into two subfamilies: Strongylinae (common name strongylins), usually large or medium-sized with a globular or funnel-shaped buccal capsule; and Cyathostominae (common name cyathostomins), usually small to medium-sized with a cylindrical buccal capsule. The increased attention to strongylid nematode parasites of horses has resulted in the need for updated diagnostic keys to these parasites using readily recognizable characters and the most recent literature on their systematics. Because the cyathostomins have been historically difficult to identify, and because they have emerged as the most significant nematode pathogens of horses, we provide a brief nomenclatural and taxonomic history and an introduction to the morphology of this group. This treatise is intended to serve as a basic working tool--providing easy identifications to genus and species of adult strongylid nematodes of equids. All strongylid nematodes normally parasitic in horses, the ass (and their hybrids), and zebras are included. The keys are illustrated with line drawings and halftone photomicrographs of each species. A short discussion of the systematics of the genus and species is provided for each genus

  7. Predicting the spread of aquatic invaders: insight from 200 years of invasion by zebra mussels.

    PubMed

    Karatayev, Alexander Y; Burlakova, Lyubov E; Mastitsky, Sergey E; Padilla, Dianna K

    2015-03-01

    Understanding factors controlling the introduction and spread of species is crucial to improving the management of both natural populations and introduced species. The zebra mussel, Dreissena polymorpha, is considered the most aggressive freshwater invader in the Northern Hemisphere, and is a convenient model system for invasion biology, offering one of the best aquatic examples for examining the invasion process. We used data on 553 of the 1040 glacial lakes in the Republic of Belarus that were examined for the presence of zebra mussels. We used these data to build, test, and construct modified models to predict the spread of this invader, including selection of important parameters that could limit the spread of this invader. In spite of 200 years of continuous invasion, by 1996, zebra mussels were found in only 16.8% of all lakes studied. Of those lakes without zebra mussels in 1996, 66% were predicted to be susceptible to invasion by zebra mussels in the future, and 33% were predicted to be immune to successful invasion due to their water chemistry. Eighty lakes free of zebra mussels in 1996 were reexamined from 1997 to 2008. Of these, zebra mussels successfully invaded an additional 31 lakes, all of which were classified initially as suitable for zebra mussels; none of the lakes previously classified as unsuitable were invaded. We used the Random Forests classification algorithm with 16 environmental variables to determine the most important factors that differed between invaded lakes and those lakes suitable for invasion that have not yet been invaded. Distance to the nearest infested lakes was found to be the most important variable, followed by the lake area, color, average depth, and concentration of chloride, magnesium, and bicarbonate. This study provides a useful approach for predicting the spread of an invader across a landscape with variable habitat suitability that can be applied to a variety of species and systems. PMID:26263665

  8. Interactions among zebra mussel shells, invertebrate prey, and Eurasian ruffe or yellow perch

    USGS Publications Warehouse

    Kolar, C.S.; Fullerton, A.H.; Martin, K.M.; Lamberti, G.A.

    2002-01-01

    The exotic zebra mussel, Dreissena polymorpha, is established in all of the Laurentian Great Lakes and may affect benthivorous fishes by increasing the complexity of benthic substrates and changing energy flow patterns within the food web. Native yellow perch, Perca flavescens, and the nonindigenous Eurasian ruffe, Gymnocephalus cernuus, are benthivores that may compete for limited food resources. As ruffe spread to areas with more dense zebra mussel populations, the zone of interaction among zebra mussels, yellow perch, and ruffe will increase and intensify. In the laboratory, the effect of zebra mussel shells on the ability of these fishes to forage on amphipods (Gammarus pseudolimnaeus) and chironomids (Chironomus plumosus) was examined in light and darkness. In 12 h, ruffe consumed more amphipods than did similar-sized yellow perch, particularly in darkness on bare cobble, and in light within zebra mussels. Amphipods decreased activity more in the presence of ruffe than yellow perch. More amphipods were found in zebra mussel shells than in bare cobble, whether or not fish were present. In darkness, when ruffe consumed more amphipods on bare cobble, amphipods became more associated with zebra mussel shells. Although ruffe consumed more amphipods than yellow perch, perch consumed more chironomids than ruffe on bare cobble. The presence of zebra mussel shells altered the relative consumption of invertebrates in some substrate-light combinations. Experiments such as these help to improve understanding of the direct and indirect effects of predation between and among native and nonindigenous species that may exert structuring forces on the nearshore communities of the Great Lakes currently or in the future.

  9. Predicting the spread of aquatic invaders: insight from 200 years of invasion by zebra mussels.

    PubMed

    Karatayev, Alexander Y; Burlakova, Lyubov E; Mastitsky, Sergey E; Padilla, Dianna K

    2015-03-01

    Understanding factors controlling the introduction and spread of species is crucial to improving the management of both natural populations and introduced species. The zebra mussel, Dreissena polymorpha, is considered the most aggressive freshwater invader in the Northern Hemisphere, and is a convenient model system for invasion biology, offering one of the best aquatic examples for examining the invasion process. We used data on 553 of the 1040 glacial lakes in the Republic of Belarus that were examined for the presence of zebra mussels. We used these data to build, test, and construct modified models to predict the spread of this invader, including selection of important parameters that could limit the spread of this invader. In spite of 200 years of continuous invasion, by 1996, zebra mussels were found in only 16.8% of all lakes studied. Of those lakes without zebra mussels in 1996, 66% were predicted to be susceptible to invasion by zebra mussels in the future, and 33% were predicted to be immune to successful invasion due to their water chemistry. Eighty lakes free of zebra mussels in 1996 were reexamined from 1997 to 2008. Of these, zebra mussels successfully invaded an additional 31 lakes, all of which were classified initially as suitable for zebra mussels; none of the lakes previously classified as unsuitable were invaded. We used the Random Forests classification algorithm with 16 environmental variables to determine the most important factors that differed between invaded lakes and those lakes suitable for invasion that have not yet been invaded. Distance to the nearest infested lakes was found to be the most important variable, followed by the lake area, color, average depth, and concentration of chloride, magnesium, and bicarbonate. This study provides a useful approach for predicting the spread of an invader across a landscape with variable habitat suitability that can be applied to a variety of species and systems.

  10. Sarcoids in captive zebras (Equus burchellii): association with bovine papillomavirus type 1 infection.

    PubMed

    Löhr, Christiane V; Juan-Sallés, Carles; Rosas-Rosas, Arely; Parás García, Alberto; Garner, Michael M; Teifke, Jens P

    2005-03-01

    Sarcoids were diagnosed in two captive zebras from different facilities. Zebra 1 (Equus burchellii boehmi) was a 4.5-yr-old, captive-born male that presented with a 9- by 7-cm inguinal mass. Seven months after surgical excision of the inguinal mass, the zebra presented with a similar lesion in the right upper eyelid that has relapsed repeatedly and has not responded to treatment including local cisplatin injections and cryosurgery. Zebra 2 (of undetermined taxon) was housed at a private wild animal farm. The zebra presented with a single, raised, 2.5- by 2.0- by 2.0-cm, ulcerated mass on the nose, and surgical excision was curative. Histologically, the three masses consisted of a dermal, compact, nonencapsulated, poorly demarcated neoplasm composed of well-differentiated spindle cells arranged in streams and whorls and accompanied by moderate epidermal hyperplasia with long rete pegs. On the basis of the morphologic resemblance to the unique equine cutaneous neoplasm, "sarcoid" was diagnosed. This is the first description of sarcoids in captive zebras. Association with bovine papillomavirus (BPV) type 1, as it occurs in horses, was demonstrated by polymerase chain reaction, nucleic acid sequencing, and in situ hybridization (ISH) on paraffin-embedded tissues from the inguinal mass of zebra 1. Sequencing revealed 98% identity of the 244-bp fragment with BPV type 1. The ISH for BPV type 1 DNA intensely stained the nuclei of neoplastic mesenchymal spindle cells. The sites and the clinical behavior of the sarcoids in these zebras are similar to those described in horses.

  11. Removal of algae by the zebra mussel (Dreissena polymorpha) population in western Lake Erie: a bioenergetics approach

    USGS Publications Warehouse

    Madenjian, Charles P.

    1995-01-01

    A bioenergetics model for growth of a zebra mussel (Dreissena polymorpha) individual was verified with observations on zebra mussel growth in western Lake Erie. The bioenergetics model was then applied to the zebra mussel population in the western basin of Lake Erie to estimate the removal of phytoplankton by mussels. According to the modeling results, the zebra mussel population consumed 5.0 million tonnes of phytoplankton, while 1.4 million tonnes of phytoplankton was deposited in pseudofeces from the mussels. Thus, a total of 6.4 ± 2.4 million tonnes of phytoplankton was removed from the water column by zebra mussel in western Lake Erie during 1990. Primary production was estimated to be 24.8 million tonnes; therefore, zebra mussel removed the equivalent of 26 ± 10% of the primary production for western Lake Erie.

  12. Habitat engineering by the invasive zebra mussel Dreissena polymorpha (Pallas) in a boreal coastal lagoon: impact on biodiversity

    NASA Astrophysics Data System (ADS)

    Zaiko, Anastasija; Daunys, Darius; Olenin, Sergej

    2009-03-01

    Habitat engineering role of the invasive zebra mussel Dreissena polymorpha (Pallas) was studied in the Curonian lagoon, a shallow water body in the SE Baltic. Impacts of live zebra mussel clumps and its shell deposits on benthic biodiversity were differentiated and referred to unmodified (bare) sediments. Zebra mussel bed was distinguished from other habitat types by higher benthic invertebrate biomass, abundance, and species richness. The impact of live mussels on biodiversity was more pronounced than the effect of shell deposits. The structure of macrofaunal community in the habitats with >103 g/m2 of shell deposits devoid of live mussels was similar to that found within the zebra mussel bed. There was a continuous shift in species composition and abundance along the gradient ‘bare sediments—shell deposits—zebra mussel bed’. The engineering impact of zebra mussel on the benthic community became apparent both in individual patches and landscape-level analyses.

  13. Development of a Bioaerosol single particle detector (BIO IN) for the Fast Ice Nucleus CHamber FINCH

    NASA Astrophysics Data System (ADS)

    Bundke, U.; Reimann, B.; Nillius, B.; Jaenicke, R.; Bingemer, H.

    2010-02-01

    In this work we present the setup and first tests of our new BIO IN detector. This detector was constructed to classify atmospheric ice nuclei (IN) for their biological content. It is designed to be coupled to the Fast Ice Nucleus CHamber FINCH. If one particle acts as an ice nucleus, it will be at least partly covered with ice at the end of the development section of the FINCH chamber. The device combines an auto-fluorescence detector and a circular depolarization detector for simultaneous detection of biological material and discrimination between water droplets, ice crystals and non activated large aerosol particles. The excitation of biological material with UV light and analysis of auto-fluorescence is a common principle used for flow cytometry, fluorescence microscopy, spectroscopy and imaging. The detection of auto-fluorescence of airborne single particles demands some more experimental effort. However, expensive commercial sensors are available for special purposes, e.g. size distribution measurements. But these sensors will not fit the specifications needed for the FINCH IN counter (e.g. high sample flow of up 10 LPM). The newly developed -low cost- BIO IN sensor uses a single high-power UV LED for the electronic excitation instead of much more expensive UV lasers. Other key advantages of the new sensor are the low weight, compact size, and the little effect on the aerosol sample, which allows it to be coupled with other instruments for further analysis. The instrument will be flown on one of the first missions of the new German research aircraft "HALO" (High Altitude and LOng range).

  14. Zebra mussel adhesion: structure of the byssal adhesive apparatus in the freshwater mussel, Dreissena polymorpha.

    PubMed

    Farsad, Nikrooz; Sone, Eli D

    2012-03-01

    The freshwater zebra mussel (Dreissena polymorpha) owes a large part of its success as an invasive species to its ability to attach to a wide variety of substrates. As in marine mussels, this attachment is achieved by a proteinaceous byssus, a series of threads joined at a stem that connect the mussel to adhesive plaques secreted onto the substrate. Although the zebra mussel byssus is superficially similar to marine mussels, significant structural and compositional differences suggest that further investigation of the adhesion mechanisms in this freshwater species is warranted. Here we present an ultrastructural examination of the zebra mussel byssus, with emphasis on interfaces that are critical to its adhesive function. By examining the attached plaques, we show that adhesion is mediated by a uniform electron dense layer on the underside of the plaque. This layer is only 10-20 nm thick and makes direct and continuous contact with the substrate. The plaque itself is fibrous, and curiously can exhibit either a dense or porous morphology. In zebra mussels, a graded interface between the animal and the substrate mussels is achieved by interdigitation of uniform threads with the stem, in contrast to marine mussels, where the threads themselves are non-uniform. Our observations of several novel aspects of zebra mussel byssal ultrastructure may have important implications not only for preventing biofouling by the zebra mussel, but for the development of new bioadhesives as well. PMID:22309789

  15. Efficacy of candidate chemicals for preventing attachment of zebra mussels (Dreissena polymorpha)

    USGS Publications Warehouse

    Cope, W.G.; Bartsch, M.R.; Marking, L.L.

    1997-01-01

    Forty-seven chemicals having potential for preventing the attachment of zebra mussels Dreissena polymorpha were identified and tested. For each chemical, 15 zebra mussels (5-8-mm shell length) in each of two replicates and six treatments were exposed for 48 h followed by a 48-h postexposure period in untreated water. Eleven of the chemicals inhibited the reattachment of zebra mussels after the 48-h exposure; eight had EC50 values ranging from 0.4 to 5.4 mg /L, and three had EC50 values ranging from 19.4 to 29.0 mg/L. Based on an analysis of chemical cost, solubility in water, anticipated treatment concentrations, and potential hazards to humans or the environment, three of the most promising chemicals, all antioxidants (butylated hydroxyanisole [BHA], tert-butylhydroquinone, and tannic acid) were tested on nontarget fish (bluegill, Lepomis macrochirus; channel catfish, Ictalurus punctatus; and rainbow trout, Oncorhynchus mykiss). These chemicals were not selectively toxic to zebra mussels; only the tests with bluegill and BHA and with channel catfish and tannic acid had 48-h LC50 values greater than the concentrations effective for preventing the reattachment of zebra mussels. Although the attachment of zebra mussels can be prevented with selected antioxidants, an alternative formulation should be investigated to minimize effects on nontarget organisms, such as fish.

  16. Effect of acute stresses on zebra fish (Danio rerio) metabolome measured by NMR-based metabolomics.

    PubMed

    Mushtaq, Mian Yahya; Marçal, Rosilene Moretti; Champagne, Danielle L; van der Kooy, Frank; Verpoorte, Robert; Choi, Young Hae

    2014-09-01

    We applied an acute stress model to zebra fish in order to measure the changes in the metabolome due to biological stress. This was done by submitting the fish to fifteen minutes of acute confinement (netting) stress, and then five minutes for the open field and light/dark field tests. A polar extract of the zebra fish was then subjected to (1)H nuclear magnetic spectroscopy. Multivariate data analysis of the spectra showed a clear separation associated to a wide range of metabolites between zebra fish that were submitted to open field and light/dark field tests. Alanine, taurine, adenosine, creatine, lactate, and histidine were high in zebra fish to which the light/dark field test was applied, regardless of stress, while acetate and isoleucine/lipids appeared to be higher in zebra fish exposed to the open field test. These results show that any change in the environment, even for a small period of time, has a noticeable physiological impact. This research provides an insight of how different mechanisms are activated under different environments to maintain the homeostasis of the body. It should also contribute to establish zebra fish as a model for metabolomics studies. PMID:25098933

  17. IMPACT OF OXYGEN CONCENTRATION ON ZEBRA MUSSEL MORTALITY

    SciTech Connect

    Daniel P. Molloy

    2003-01-27

    These tests have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels in environments having dissolved oxygen (DO) concentrations ranging from very low to very high. The results suggest that the highest mussel kill can be achieved in moderately to highly aerated environments, while kill may be 0-20% lower under conditions of very low oxygen. For example, under highly oxygenated conditions 97% kill was achieved while conditions having low DO produced 79% mussel kill. Service water measured in a local power plant indicated that DO concentrations were in the range of 8-9 ppm (e.g., highly aerated) within their pipes. Therefore, we will not expect to see decreases in the efficacy of CL0145A treatments due to oxygen levels within such power plant pipes.

  18. Ultrastructural and Histochemical Characterization of the Zebra Mussel Adhesive Apparatus

    NASA Astrophysics Data System (ADS)

    Farsad, Nikrooz

    Since their accidental introduction into the Great Lakes in mid- to late-1980s, the freshwater zebra mussels, Dreissena polymorpha, have colonized most lakes and waterways across eastern North America. Their rapid spread is partly attributed to their ability to tenaciously attach to hard substrates via an adhesive apparatus called the byssus, resulting in serious environmental and economic impacts. A detailed ultrastructural study of the byssus revealed a 10 nm adhesive layer at the attachment interface. Distributions of the main adhesive amino acid, 3,4-dihydroxyphenylalanine (DOPA), and its oxidizing (cross-linking) enzyme, catechol oxidase, were determined histochemically. It was found that, upon aging, DOPA levels remained high in the portion of the byssus closest to the interface, consistent with an adhesive role. In contrast, reduced levels of DOPA corresponded well with high levels of catechol oxidase in the load-bearing component of the byssus, presumably forming cross-links and increasing the cohesive strength.

  19. Striped-tailed Yellow-finch nesting success in abandoned mining pits from central Brazilian cerrado.

    PubMed

    Gressler, D T; Marini, M Â

    2015-01-01

    Suitability of degraded areas as breeding habitats can be tested through assessment of nest predation rates. In this study we estimated nest success in relation to several potential predictors of nest survival in the Stripe-tailed Yellow-finch (Sicalis citrina) breeding in abandoned mining pits at Brasília National Park. We monitored 73 nests during the 2007-breeding season. Predation was the main cause of nest failure (n = 48, 66%); while six nests were abandoned (8%) and 19 nests produced young (26%). Mayfield's daily survival rates and nest success were 0.94 and 23%, respectively. Our results from nest survival models on program MARK indicated that daily survival rates increase linearly towards the end of the breeding season and decrease as nests aged. None of the nest individual covariates we tested - nest height, nest size, nest substrate, and edge effect - were important predictors of nest survival; however, nests placed on the most common plant tended to have higher survival probabilities. Also, there was no observer effect on daily survival rates. Our study suggests that abandoned mining pits may be suitable alternative breeding habitats for Striped-tailed Yellow-finches since nest survival rates were similar to other studies in the central cerrado region.

  20. Multi-locus sequence typing confirms the clonality of Trichomonas gallinae isolates circulating in European finches.

    PubMed

    Ganas, Petra; Jaskulska, Barbara; Lawson, Becki; Zadravec, Marko; Hess, Michael; Bilic, Ivana

    2014-04-01

    In recent years, Trichomonas gallinae emerged as the causative agent of an infectious disease of passerine birds in Europe leading to epidemic mortality of especially greenfinches Chloris chloris and chaffinches Fringilla coelebs. After the appearance of finch trichomonosis in the UK and Fennoscandia, the disease spread to Central Europe. Finch trichomonosis first reached Austria and Slovenia in 2012. In the present study the genetic heterogeneity of T. gallinae isolates from incidents in Austria and Slovenia were investigated and compared with British isolates. For this purpose comparative sequence analyses of the four genomic loci ITS1-5.8S-ITS2, 18S rRNA, rpb1 and Fe-hydrogenase were performed. The results corroborate that one clonal T. gallinae strain caused the emerging infectious disease within passerine birds and that the disease is continuing to spread in Europe. The same clonal strain was also found in a columbid bird from Austria. Additionally, the present study demonstrates clearly the importance of multi-locus sequence typing for discrimination of circulating T. gallinae strains. PMID:24476813

  1. How well can fishes prey on zebra mussels in eastern North America?

    USGS Publications Warehouse

    French, John R. P.

    1993-01-01

    Literature on mollusk-eating fishes was reviewed to determine the potential for different species of fish to control zebra mussels in eastern North America. At least six species are potential predators of zebra mussels because they possess (1) both upper and lower pharyngeal teeth or (2) lower pharyngeal teeth and chewing pads located on the dorsal roof for crushing mollusk shells. Freshwater drum (Aplodinotus grunniens) and two centrarchids, redear sunfish (Lepomis microlophus) and pumpkinseed (L. gibbosus), possess both upper and lower pharyngeal teeth and are likely to consume more zebra mussels than fishes with only lower pharyngeal teeth. Only two catostomid species, copper and river redhorses (Moxostoma hubbsi and M. carinatum), have chewing pads that enable them to crush mollusks. The exotic omnivorous common carp (Cyprinus carpio), possessing lower teeth and a chewing pad, may prey on zebra mussels when aquatic insect larvae, its preferred food, become rare. Managing populations of drum, sunfishes and redhorses to reduce exploitation of large individuals and improve their habitats are suggested as means to intensify biological control of zebra mussels in eastern North America. Other Eurasian molluscivores, the roach (Rutilus rutilus) and the black carp (Mylopharyngodon piceus) should not be introduced into North America because research has shown repeatedly that an introduced biological controller usually does not forage for unwanted pests or reside only in preferred habitats of pests. Drum, sunfishes and redhorses should be preferred over these exotics as biological controllers of zebra mussels in North America because these native fishes will likely occupy newly established habitats of zebra mussels.

  2. Expression analysis of the speech-related genes FoxP1 and FoxP2 and their relation to singing behavior in two songbird species.

    PubMed

    Chen, Qianqian; Heston, Jonathan B; Burkett, Zachary D; White, Stephanie A

    2013-10-01

    Humans and songbirds are among the rare animal groups that exhibit socially learned vocalizations: speech and song, respectively. These vocal-learning capacities share a reliance on audition and cortico-basal ganglia circuitry, as well as neurogenetic mechanisms. Notably, the transcription factors Forkhead box proteins 1 and 2 (FoxP1, FoxP2) exhibit similar expression patterns in the cortex and basal ganglia of humans and the zebra finch species of songbird, among other brain regions. Mutations in either gene are associated with language disorders in humans. Experimental knock-down of FoxP2 in the basal ganglia song control region Area X during song development leads to imprecise copying of tutor songs. Moreover, FoxP2 levels decrease naturally within Area X when zebra finches sing. Here, we examined neural expression patterns of FoxP1 and FoxP2 mRNA in adult Bengalese finches, a songbird species whose songs exhibit greater sequence complexity and increased reliance on audition for maintaining their quality. We found that FoxP1 and FoxP2 expression in Bengalese finches is similar to that in zebra finches, including strong mRNA signals for both factors in multiple song control nuclei and enhancement of FoxP1 in these regions relative to surrounding brain tissue. As with zebra finches, when Bengalese finches sing, FoxP2 is behaviorally downregulated within basal ganglia Area X over a similar time course, and expression negatively correlates with the amount of singing. This study confirms that in multiple songbird species, FoxP1 expression highlights song control regions, and regulation of FoxP2 is associated with motor control of song.

  3. Seasonal effects of the zebra mussel (Dreissena polymorpha) on sediment denitrification rates in Pool 8 of the Upper Mississippi River

    USGS Publications Warehouse

    Bruesewitz, Denise A.; Tank, Jennifer L.; Bernot, Melody J.; Richardson, William B.; Strauss, Eric A.

    2006-01-01

    Zebra mussels (Dreissena polymorpha) have altered the structure of invaded ecosystems and exhibit characteristics that suggest they may influence ecosystem processes such as nitrogen (N) cycling. We measured denitrification rates seasonally on sediments underlying zebra mussel beds collected from the impounded zone of Navigation Pool 8 of the Upper Mississippi River. Denitrification assays were amended with nutrients to characterize variation in nutrient limitation of denitrification in the presence or absence of zebra mussels. Denitrification rates at zebra mussel sites were high relative to sites without zebra mussels in February 2004 (repeated measures analysis of variance (RM ANOVA), p = 0.005), potentially because of high NO3-N variability from nitrification of high NH4+ zebra mussel waste. Denitrification rates were highest in June 2003 (RM ANOVA, p 3-N concentrations during the study (linear regression, R2 = 0.72, p p ≤ 0.01). Examining how zebra mussels influence denitrification rates will aid in developing a more complete understanding of the impact of zebra mussels and more effective management strategies of eutrophic waters.

  4. Effects of temperature and aerial exposure on the BOD of waste zebra mussels removed from navigational locks.

    PubMed

    Aldridge, D W; Payne, B S

    2001-08-01

    This laboratory study evaluated the effects of temperature and aerial exposure on BOD5 (5-day BOD) of waste zebra mussels of the type generated by maintenance operations on dams and navigational locks. The term waste zebra mussels includes the mussels and their associated debris with the latter including sediment, feces, pseudofeces and other small aquatic organisms. The BOD5 of waste zebra mussel was evaluated after aerial exposure of 3 and 10 days at temperatures of 5, 10, and 20 degrees C. The mean BOD5 values for waste zebra mussels in this study ranged from 18,500 to 30,600 mg O2/l. Factorial ANOVA analysis revealed that both temperature and aerial exposure had a negative effect on waste zebra mussel BOD5 (P<0.05) but there was no significant interaction effect (P = 0.119). Multiple regression analysis predicted that for the range of treatment conditions used in this study each 1 degrees C increase in temperature reduced the waste zebra mussel BOD5 by 284mg O2/l or 0.93% of the maximum mean BOD5. Each I day increase in aerial exposure reduced waste zebra mussel BOD5 by 987 mg O2/l or 3.22% of the maximum mean BOD5. Aerial exposure of waste zebra mussels substantially reduces waste BOD5.

  5. LETHALITY OF PSEUDOMONAS FLUORESCENS STRAIN CLO145A TO THE 2 ZEBRA MUSSEL SPECIES PRESENT IN NORTH AMERICA

    SciTech Connect

    Daniel P. Molloy

    2001-10-28

    These experiments indicated that bacterial strain CL0145A of Pseudomonas fluorescens is equally lethal to the 2 zebra mussel species present in North America, Dreissena polymorpha and Dreissena bugensis. Thus, this bacterial strain should be equally effective at killing zebra mussels in power plant pipes, irrespective of which species is present.

  6. Modeling the Role of Zebra Mussels in the Proliferation of Blue-green Algae in Saginaw Bay, Lake Huron

    EPA Science Inventory

    Under model assumptions from Saginaw Bay 1991, selective rejection of blue-green algae by zebra mussels appears to be a necessary factor in the enhancement of blue-green algae production in the presence of zebra mussels. Enhancement also appears to depend on the increased sedime...

  7. Bioaccumulation of human waterborne protozoa by zebra mussel (Dreissena polymorpha): interest for water biomonitoring.

    PubMed

    Palos Ladeiro, M; Aubert, D; Villena, I; Geffard, A; Bigot, A

    2014-01-01

    Cryptosporidium parvum, Giardia duodenalis and Toxoplasma gondii are ubiquitous pathogens, which waterborne transmission has been largely demonstrated. Since they can be found in various watercourses, interactions with aquatic organisms are possible. Protozoan detection for watercourses biomonitoring is currently based on large water filtration. The zebra mussel, Dreissena polymorpha, is a choice biological model in ecotoxicological studies which are already in use to detect chemical contaminations in watercourses. In the present study, the zebra mussel was tested as a new tool for detecting water contamination by protozoa. In vivo exposures were conducted in laboratory experiments. Zebra mussel was exposed to various protozoan concentrations for one week. Detection of protozoa was realized by Taqman real time qPCR. Our experiments evidenced C. parvum, G. duodenalis and T. gondii oocyst bioaccumulation by mussels proportionally to ambient contamination, and significant T. gondii prevalence was observed in muscle tissue. To our knowledge, this is the first study that demonstrates T. gondii oocyst accumulation by zebra mussel. The results from this study highlight the capacity of zebra mussels to reveal ambient biological contamination, and thus to be used as a new effective tool in sanitary biomonitoring of water bodies. PMID:24112626

  8. Novel proteins identified in the insoluble byssal matrix of the freshwater zebra mussel.

    PubMed

    Gantayet, Arpita; Rees, David J; Sone, Eli D

    2014-04-01

    The freshwater zebra mussel, Dreissena polymorpha, is an invasive, biofouling species that adheres to a variety of substrates underwater, using a proteinaceous anchor called the byssus. The byssus consists of a number of threads with adhesive plaques at the tips. It contains the unusual amino acid 3, 4-dihydroxyphenylalanine (DOPA), which is believed to play an important role in adhesion, in addition to providing structural integrity to the byssus through cross-linking. Extensive DOPA cross-linking, however, renders the zebra mussel byssus highly resistant to protein extraction, and therefore limits byssal protein identification. We report here on the identification of seven novel byssal proteins in the insoluble byssal matrix following protein extraction from induced, freshly secreted byssal threads with minimal cross-linking. These proteins were identified by LC-MS/MS analysis of tryptic digests of the matrix proteins by spectrum matching against a zebra mussel cDNA library of genes unique to the mussel foot, the organ that secretes the byssus. All seven proteins were present in both the plaque and thread. Comparisons of the protein sequences revealed common features of zebra mussel byssal proteins, and several recurring sequence motifs. Although their sequences are unique, many of the proteins display similarities to marine mussel byssal proteins, as well as to adhesive and structural proteins from other species. The large expansion of the byssal proteome reported here represents an important step towards understanding zebra mussel adhesion. PMID:24057171

  9. How the zebra got its stripes: a problem with too many solutions

    PubMed Central

    Larison, Brenda; Harrigan, Ryan J.; Thomassen, Henri A.; Rubenstein, Daniel I.; Chan-Golston, Alec M.; Li, Elizabeth; Smith, Thomas B.

    2015-01-01

    The adaptive significance of zebra stripes has thus far eluded understanding. Many explanations have been suggested, including social cohesion, thermoregulation, predation evasion and avoidance of biting flies. Identifying the associations between phenotypic and environmental factors is essential for testing these hypotheses and substantiating existing experimental evidence. Plains zebra striping pattern varies regionally, from heavy black and white striping over the entire body in some areas to reduced stripe coverage with thinner and lighter stripes in others. We examined how well 29 environmental variables predict the variation in stripe characteristics of plains zebra across their range in Africa. In contrast to recent findings, we found no evidence that striping may have evolved to escape predators or avoid biting flies. Instead, we found that temperature successfully predicts a substantial amount of the stripe pattern variation observed in plains zebra. As this association between striping and temperature may be indicative of multiple biological processes, we suggest that the selective agents driving zebra striping are probably multifarious and complex. PMID:26064590

  10. Use of on-site refugia to protect unionid populations from zebra mussel-induced mortality

    USGS Publications Warehouse

    Nichols, S. Jerrine; Black, M. Glen; Allen, Jeffrey D.

    2000-01-01

    Protecting unionid populations as zebra mussels spread into inland waterways has relied mainly on relocating at-risk animals into aquaculture facilities. While such relocations are the only viable management technique for some populations, facility availability is limited, leaving many unionids facing extirpation. Another management strategy is in-situ protection either by enhancing natural refugia or by creating managed refugia. We have reviewed all reports of natural refugia and found that refugia for unionids can be found in many areas. There are many habitats where zebra mussel colonization has been limited, or of a temporary nature. Within zebra mussel infested areas, unionid communities continue to survive in some shallow water sites such as estuaries, deltas, and lake-connected wetlands. Managed refugia can be created in areas where natural refugia do not exist. We present a case study on recent efforts to create refugia in an area with rapidly expanding zebra mussel populations. Preliminary analysis of unionid body condition indicates that removal of encrusted zebra mussels only once a year can improve unionid condition factors and decrease mortality. Natural and managed refugia can provide an additional conservation management option in some areas.

  11. Rotationally driven 'zebra stripes' in Earth's inner radiation belt.

    PubMed

    Ukhorskiy, A Y; Sitnov, M I; Mitchell, D G; Takahashi, K; Lanzerotti, L J; Mauk, B H

    2014-03-20

    Structured features on top of nominally smooth distributions of radiation-belt particles at Earth have been previously associated with particle acceleration and transport mechanisms powered exclusively by enhanced solar-wind activity. Although planetary rotation is considered to be important for particle acceleration at Jupiter and Saturn, the electric field produced in the inner magnetosphere by Earth's rotation can change the velocity of trapped particles by only about 1-2 kilometres per second, so rotation has been thought inconsequential for radiation-belt electrons with velocities of about 100,000 kilometres per second. Here we report that the distributions of energetic electrons across the entire spatial extent of Earth's inner radiation belt are organized in regular, highly structured and unexpected 'zebra stripes', even when the solar-wind activity is low. Modelling reveals that the patterns are produced by Earth's rotation. Radiation-belt electrons are trapped in Earth's dipole-like magnetic field, where they undergo slow longitudinal drift motion around the planet because of the gradient and curvature of the magnetic field. Earth's rotation induces global diurnal variations of magnetic and electric fields that resonantly interact with electrons whose drift period is close to 24 hours, modifying electron fluxes over a broad energy range into regular patterns composed of multiple stripes extending over the entire span of the inner radiation belt. PMID:24646996

  12. Rotationally driven 'zebra stripes' in Earth's inner radiation belt.

    PubMed

    Ukhorskiy, A Y; Sitnov, M I; Mitchell, D G; Takahashi, K; Lanzerotti, L J; Mauk, B H

    2014-03-20

    Structured features on top of nominally smooth distributions of radiation-belt particles at Earth have been previously associated with particle acceleration and transport mechanisms powered exclusively by enhanced solar-wind activity. Although planetary rotation is considered to be important for particle acceleration at Jupiter and Saturn, the electric field produced in the inner magnetosphere by Earth's rotation can change the velocity of trapped particles by only about 1-2 kilometres per second, so rotation has been thought inconsequential for radiation-belt electrons with velocities of about 100,000 kilometres per second. Here we report that the distributions of energetic electrons across the entire spatial extent of Earth's inner radiation belt are organized in regular, highly structured and unexpected 'zebra stripes', even when the solar-wind activity is low. Modelling reveals that the patterns are produced by Earth's rotation. Radiation-belt electrons are trapped in Earth's dipole-like magnetic field, where they undergo slow longitudinal drift motion around the planet because of the gradient and curvature of the magnetic field. Earth's rotation induces global diurnal variations of magnetic and electric fields that resonantly interact with electrons whose drift period is close to 24 hours, modifying electron fluxes over a broad energy range into regular patterns composed of multiple stripes extending over the entire span of the inner radiation belt.

  13. Thermal treatment effectively controls zebra mussels at Illinois power plants

    SciTech Connect

    Marcus, R.I. ); Wahlert, S.L. )

    1994-12-01

    This article describes how a Commonwealth Edison Co. (ComEd) task force finds thermal treatment method most cost-effective with the least impact on station operation and the environment. Thermal treatment is accomplished by recirculating condenser discharge to raise circulating water (CW) and service water (SW) temperatures to 95 F. This treatment's effectiveness was demonstrated at the company's State Line Station in 1990 and 1991. In parallel with the State Line demonstration, a ComEd task force assessed treatment options for all of its stations. The task force determined that thermal treatment was the least-cost control approach considering construction costs and long-term operating and maintenance (O and M) expenditures. Compared to other alternatives, thermal treatment minimizes unit deratings and outages and minimizes impact to the environment. Based on the task force's assessment and the successful treatment at State Line Station, thermal treatment was selected as the preferred, least-cost method to control zebra mussels at the company's fossil-fueled stations.

  14. Phylogeography and systematics of zebra mussels and related species.

    PubMed

    Gelembiuk, Gregory W; May, Gemma E; Lee, Carol Eunmi

    2006-04-01

    The genus Dreissena includes two widespread and aggressive aquatic invaders, the zebra mussel, Dreissena polymorpha, and the quagga mussel, Dreissena bugensis. This genus evolved in the Ponto-Caspian Sea basin, characterized by dynamic instability over multiple timescales and a unique evolutionary environment that may predispose to invasiveness. The objectives of this study were to gain insights into the demographic history of Dreissena species in their endemic range, to reconstruct intraspecific phylogeographic relationships among populations, and to clarify systematics of the genus, using DNA sequences from the mitochondrial cytochrome oxidase I (COI) gene. We found four deeply diverged clades within this genus, with a basal split that approximately coincided with the Cretaceous-Tertiary boundary. Divergence events within the four base clades were much more recent, corresponding to geographically disjunct sets of populations, which might represent species complexes. Across all taxa, populations of Dreissena shared a common pattern of genetic signatures indicating historical population bottlenecks and expansions. Haplotype diversity was relatively low in Ponto-Caspian drainages relative to more stable tectonic lakes in Greece, Macedonia, and Turkey. The phylogeographic and demographic patterns in the endemic range of Dreissena might have resulted from vicariance events, habitat instability, and the high fecundity and passive dispersal of these organisms.

  15. Changes in ultra-structures and electrophysiological properties in HVC of untutored and deafened Bengalese finches relation to normally reared birds: implications for song learning.

    PubMed

    Peng, Zhe; Zhang, XueBo; Xi, Chao; Zeng, ShaoJu; Liu, Nan; Zuo, MingXue; Zhang, XinWen

    2012-12-01

    Songbirds are increasingly used as an experimentally tractable system to study the neurobiological underpinnings of vocal learning. To gain additional insights into how birdsongs are learned, we compared the size of HVC, the high vocal center for song production, and its ultrastructural or electrophysiological properties between the normally reared Bengalese finches, and the untutored or deafened ones before the onset of sensory learning (around post-hatching day 20). Our results showed that HVC had more synapses and concave synaptic curvature, but fewer perforated synapse, in the untutored or deafened birds in comparison with those in the normally reared birds. Although there was no significant difference of the ratio of straight or compound synapses, there was an increasing tendency for the untutored and deafened birds to possess more straight and compound synapses. These data revealed that synapses in the isolated or deafened birds had lower synapse activity in relation to those with normal hearing. This was confirmed by our electrophysiological results to show significant decreases in the firing rates of spike or burst in the isolated or deafened birds in the three types of HVC neurons i.e., putative X-projecting neurons, RA-projecting neurons and interneurons. In addition, low firing frequency (<10Hz) occurred much more in the above three types of HVC neurons in the tutored or deafened birds than in the normally reared birds. These data suggest that all the three putative types of neurons in HVC might be involved in the activity of the production of adult normal songs.

  16. Zebra Crossing Spotter: Automatic Population of Spatial Databases for Increased Safety of Blind Travelers

    PubMed Central

    Ahmetovic, Dragan; Manduchi, Roberto; Coughlan, James M.; Mascetti, Sergio

    2016-01-01

    In this paper we propose a computer vision-based technique that mines existing spatial image databases for discovery of zebra crosswalks in urban settings. Knowing the location of crosswalks is critical for a blind person planning a trip that includes street crossing. By augmenting existing spatial databases (such as Google Maps or OpenStreetMap) with this information, a blind traveler may make more informed routing decisions, resulting in greater safety during independent travel. Our algorithm first searches for zebra crosswalks in satellite images; all candidates thus found are validated against spatially registered Google Street View images. This cascaded approach enables fast and reliable discovery and localization of zebra crosswalks in large image datasets. While fully automatic, our algorithm could also be complemented by a final crowdsourcing validation stage for increased accuracy. PMID:26824080

  17. AFLP analysis and zebra disease resistance identification of 40 sisal genotypes in China.

    PubMed

    Gao, Jianming; Luoping; Guo, Chaoming; Li, Jinzhi; Liu, Qiaolian; Chen, Helong; Zhang, Shiqing; Zheng, Jinlong; Jiang, Chenji; Dai, Zhenzhen; Yi, Kexian

    2012-05-01

    Sisal is the most important fiber crop in tropical and subtropical areas in China and the world. Zebra disease is a serious threat to the main cultivar Agave hybrid No.11648 (H.11648) worldwide. To select germplasm materials with zebra disease resistance for breeding, the fluorescent amplified fragment length polymorphism (AFLP) technique was used to make a cluster analysis of the genetic relationships of 40 sisal genotypes grown in China, and Phytophthora nicotianae was used to inoculate the 40 genotypes to identify their resistance to zebra disease. As a result, the similarity coefficient among 40 sisal genotypes was found to be 0.44-0.83 and the 40 genotypes show different levels of disease resistance. According to the AFLP analysis, the disease resistance and chromosomal ploidy, it can be reasoned that, A. attenuata var. marginata, Dong 109, Nan ya 1 and A. attenuata are suitable for hybridization with H.11648 to breed a new disease-resistant variety. PMID:22327644

  18. Structural activity relationship studies of zebra mussel antifouling and antimicrobial agents from verongid sponges.

    PubMed

    Diers, Jeffrey A; Pennaka, Hari Kishore; Peng, Jiangnan; Bowling, John J; Duke, Stephen O; Hamann, Mark T

    2004-12-01

    Several dibromotyramine derivatives including moloka'iamine were selected as potential zebra mussel (Dreissena polymorpha) antifoulants due to the noteworthy absence of fouling observed on sponges of the order Verongida. Sponges of the order Verongida consistently produce these types of bromotyrosine-derived secondary metabolites. Previously reported antifouling data for the barnacle Balanus amphitrite(EC50 = 12.2 microM) support the results reported here that the compound moloka'iamine may be a potential zebra mussel antifoulant compound (EC50 = 10.4 microM). The absence of phytotoxic activity of the compound moloka'iamine toward Lemna pausicostata and, most importantly, the compound's significant selectivity against macrofouling organisms such as zebra mussels suggest the potential utility of this compound as a naturally derived antifoulant lead.

  19. Structural Activity Relationship Studies of Zebra Mussel Antifouling and Antimicrobial Agents from Verongid Sponges

    PubMed Central

    Diers, Jeffrey A.; Pennaka, Hari Kishore; Peng, Jiangnan; Bowling, John J.; Duke, Stephen O.; Hamann, Mark T.

    2016-01-01

    Several dibromotyramine derivatives including moloka’iamine were selected as potential zebra mussel (Dreissena polymorpha) antifoulants due to the noteworthy absence of fouling observed on sponges of the order Verongida. Sponges of the order Verongida consistently produce these types of bromotyrosine-derived secondary metabolites. Previously reported antifouling data for the barnacle Balanus amphitrite (EC50 = 12.2 μM) support the results reported here that the compound moloka’iamine may be a potential zebra mussel antifoulant compound (EC50 = 10.4 μM). The absence of phytotoxic activity of the compound moloka’iamine toward Lemna pausicostata and, most importantly, the compound’s significant selectivity against macrofouling organisms such as zebra mussels suggest the potential utility of this compound as a naturally derived antifoulant lead. PMID:15620267

  20. Cannabinoids inhibit zebra mussel (Dreissena polymorpha) byssal attachment: a potentially green antifouling technology.

    PubMed

    Angarano, Maj-Britt; McMahon, Robert F; Schetz, John A

    2009-01-01

    Macrofouling by zebra mussels (Dreissena polymorpha) has serious environmental, economic and legal consequences for freshwater shipping and raw water facilities. Current antifouling technologies, such as organometallics or aggressive oxidisers, have negative environmental impacts limiting their application. As part of an effort to discover antifoulants with a reduced environmental footprint, the endocannabinoid, anandamide and nine other compounds sharing structural or functional features were tested for their ability to inhibit zebra mussel byssal attachment. A byssal attachment bioassay identified six efficacious compounds; four compounds also had no negative impact on mussels at concentrations maximally inhibiting byssal attachment and three of them had no significant cumulative toxicity towards a non-target organism, Daphnia magna. This discovery demonstrates that both naturally occurring and synthetic cannabinoids can serve as non-toxic efficacious zebra mussel antifoulants. Applications with this technology may lead to a new genre of cleaner antifoulants, because the strategy is to prevent attachment rather than to poison mussels.

  1. Lessons learned in over 100 zebra mussel control applications at industrial facilities

    SciTech Connect

    McGough, C.M.; Gilland, P.H.; Muia, R.A.

    1998-12-31

    Since their introduction into US waterways, Zebra Mussels (Dreissena polymorphae) have spread rapidly throughout the Great Lakes and Mississippi regions. These mussels have continued to colonize the intake pipes of industrial water supplies and water distribution systems throughout the affected areas. Their colonization has compromised plant safety and production efficiency, and steadily increased costs to water users. The design of each industrial plant water distribution system is unique. A comprehensive zebra mussel control strategy using the best available options must be considered in each specific situation. This paper discusses the successful use of one strategy (a quaternary ammonia-based molluscicide) in the battle against zebra mussels. The commercial life cycle of an industrial molluscicide began with initial toxicity screening in the laboratory. The evaluation continued at plant sites through field trials and applications. Lessons learned from these experiences helped direct the efforts toward the development of a second generation program.

  2. Phyllodistomum folium (Trematoda: Gorgoderidae) infecting zebra mussels (Dreissena polymorpha) in the Ebro River, Spain.

    PubMed

    Peribáñez, Miguel A; Elrío, María L; Gracia, María J; Fernández de Luco, Daniel; Castillo, Juan A; Lucientes, Javier; Cia, Imanol

    2006-06-01

    Zebra mussels (Dreissena polymorpha) were first found in the Ebro River (Spain) in Ribaroja reservoir, in the summer of 2001. This paper reports a study to detect parasites in this bivalve species. From September 2003 to August 2004, a total of 1380 zebra mussels were collected and dissected or sectioned in paraffin and haematoxylin and eosin staining. We observed the presence of Phyllodistomum folium (Olfers, 1816) in two hosts (prevalence 0.14%). Sporocysts containing metacercariae were located within the gill lamellae. One of the mussels was collected in January and the other one in July. In both cases the shell length was >2 cm. P. folium had not been previously reported in Spain and D. polymorpha is its only known intermediate host. It represents a new invasive species in this river basin, presumably introduced together with the zebra mussels.

  3. Low frequency sound as a control measure for zebra mussel fouling

    SciTech Connect

    Donskoy, D.M.; Ludyanskiy, M.L.

    1995-06-01

    The study of the effect of acoustic energy on zebra mussels first began in the Soviet Union over 30 years ago, where researchers indicated the feasibility of reducing Dreissena fouling, in particular on cooling systems. However, these studies were discontinued due to the successful use of chlorination and the relatively low level of technology at that time in the Soviet Union. Interest in the use of acoustic energy as a control measure has been revived, and the three major approaches are: (1) cavitation, (2) sound treatment, and (3) sound treatment. The objective of the present paper is to determine the feasibility and effectivensss of low frequency sound techniques to fight zebra mussel fouling. A number of experiments were performed, and the results are presented and discussed. It is concluded that low frequency sound can be an effective means of control of zebra mussel fouling.

  4. AFLP analysis and zebra disease resistance identification of 40 sisal genotypes in China.

    PubMed

    Gao, Jianming; Luoping; Guo, Chaoming; Li, Jinzhi; Liu, Qiaolian; Chen, Helong; Zhang, Shiqing; Zheng, Jinlong; Jiang, Chenji; Dai, Zhenzhen; Yi, Kexian

    2012-05-01

    Sisal is the most important fiber crop in tropical and subtropical areas in China and the world. Zebra disease is a serious threat to the main cultivar Agave hybrid No.11648 (H.11648) worldwide. To select germplasm materials with zebra disease resistance for breeding, the fluorescent amplified fragment length polymorphism (AFLP) technique was used to make a cluster analysis of the genetic relationships of 40 sisal genotypes grown in China, and Phytophthora nicotianae was used to inoculate the 40 genotypes to identify their resistance to zebra disease. As a result, the similarity coefficient among 40 sisal genotypes was found to be 0.44-0.83 and the 40 genotypes show different levels of disease resistance. According to the AFLP analysis, the disease resistance and chromosomal ploidy, it can be reasoned that, A. attenuata var. marginata, Dong 109, Nan ya 1 and A. attenuata are suitable for hybridization with H.11648 to breed a new disease-resistant variety.

  5. Effects of immunosuppression on encephalitis virus infection in the house finch, Carpodacus mexicanus.

    PubMed

    Reisen, William K; Chiles, Robert E; Green, Emily N; Fang, Ying; Mahmood, Farida; Martinez, Vincent M; Laver, Thomas

    2003-03-01

    Immunosuppression of house finches was attempted by blood feeding Culex tarsalis Coquillett mosquitoes or by injecting birds with the corticosteroid dexamethasone or the immunosuppressant drug cyclophosphamide before and after inoculation with western equine encephalomyelitis or St. Louis encephalitis viruses. Mosquito bites (8-37 females blood feeding on each bird over a 3-d period) did not enhance the viremia response or increase the frequency of chronic infection. In contrast, dexamethasone and cyclophosphamide enhanced the amplitude and duration of the viremia response, but had no consistent effect on the antibody responses as measured by enzyme immunoassay or plaque reduction neutralization assay. Elevated viremias were followed by increases in the frequency of chronic infections with St. Louis encephalitis, but not western equine encephalomyelitis. Immunosuppression may provide a useful tool to study the chronic infection process of flaviviruses in vertebrates. PMID:12693850

  6. Darwin's finches and their diet niches: the sympatric coexistence of imperfect generalists.

    PubMed

    De León, L F; Podos, J; Gardezi, T; Herrel, A; Hendry, A P

    2014-06-01

    Adaptive radiation can be strongly influenced by interspecific competition for resources, which can lead to diverse outcomes ranging from competitive exclusion to character displacement. In each case, sympatric species are expected to evolve into distinct ecological niches, such as different food types, yet this expectation is not always met when such species are examined in nature. The most common hypotheses to account for the coexistence of species with substantial diet overlap rest on temporal variation in niches (often diets). Yet spatial variation in niche overlap might also be important, pointing to the need for spatiotemporal analyses of diet and diet overlap between closely related species persisting in sympatry. We here perform such an analysis by characterizing the diets of, and diet overlap among, four sympatric Darwin's ground finch species at three sites and over 5 years on a single Galápagos island (Santa Cruz). We find that the different species have broadly similar and overlapping diets - they are to some extent generalists and opportunists - yet we also find that each species retains some 'private' resources for which their morphologies are best suited. Importantly, use of these private resources increased considerably, and diet overlap decreased accordingly, when the availability of preferred shared foods, such as arthropods, was reduced during drought conditions. Spatial variation in food resources was also important. These results together suggest that the ground finches are 'imperfect generalists' that use overlapping resources under benign conditions (in space or time), but then retreat to resources for which they are best adapted during periods of food limitation. These conditions likely promote local and regional coexistence. PMID:24750315

  7. State-space modeling of population sizes and trends in Nihoa Finch and Millerbird

    USGS Publications Warehouse

    Gorresen, P. Marcos; Brinck, Kevin W.; Camp, Richard J.; Farmer, Chris; Plentovich, Sheldon M.; Banko, Paul C.

    2016-01-01

    Both of the 2 passerines endemic to Nihoa Island, Hawai‘i, USA—the Nihoa Millerbird (Acrocephalus familiaris kingi) and Nihoa Finch (Telespiza ultima)—are listed as endangered by federal and state agencies. Their abundances have been estimated by irregularly implemented fixed-width strip-transect sampling from 1967 to 2012, from which area-based extrapolation of the raw counts produced highly variable abundance estimates for both species. To evaluate an alternative survey method and improve abundance estimates, we conducted variable-distance point-transect sampling between 2010 and 2014. We compared our results to those obtained from strip-transect samples. In addition, we applied state-space models to derive improved estimates of population size and trends from the legacy time series of strip-transect counts. Both species were fairly evenly distributed across Nihoa and occurred in all or nearly all available habitat. Population trends for Nihoa Millerbird were inconclusive because of high within-year variance. Trends for Nihoa Finch were positive, particularly since the early 1990s. Distance-based analysis of point-transect counts produced mean estimates of abundance similar to those from strip-transects but was generally more precise. However, both survey methods produced biologically unrealistic variability between years. State-space modeling of the long-term time series of abundances obtained from strip-transect counts effectively reduced uncertainty in both within- and between-year estimates of population size, and allowed short-term changes in abundance trajectories to be smoothed into a long-term trend.

  8. Food restriction negatively affects multiple levels of the reproductive axis in male house finches, Haemorhous mexicanus.

    PubMed

    Valle, Shelley; Carpentier, Elodie; Vu, Bethany; Tsutsui, Kazuyoshi; Deviche, Pierre

    2015-09-01

    Nutrition influences reproductive functions across vertebrates, but the effects of food availability on the functioning of the hypothalamic-pituitary-gonadal (HPG) axis in wild birds and the mechanisms mediating these effects remain unclear. We investigated the influence of chronic food restriction on the HPG axis of photostimulated house finches, Haemorhous mexicanus. Food-restricted birds had underdeveloped testes with smaller seminiferous tubules than ad libitum-fed birds. Baseline plasma testosterone increased in response to photostimulation in ad libitum-fed but not in food-restricted birds. Food availability did not, however, affect the plasma testosterone increase resulting from a gonadotropin-releasing hormone-I (GnRH) or a luteinizing hormone (LH) challenge. The number of hypothalamic GnRH immunoreactive (ir) but not proGnRH-ir perikarya was higher in food-restricted than in ad libitum-fed finches, suggesting inhibited secretion of GnRH. Hypothalamic gonadotropin-inhibitory hormone (GnIH)-ir and neuropeptide Y (NPY)-ir were not affected by food availability. Plasma corticosterone (CORT) was also not affected by food availability, indicating that the observed HPG axis inhibition did not result from increased activity of the hypothalamic-pituitary-adrenal (HPA) axis. This study is among the first to examine multilevel functional changes in the HPG axis in response to food restriction in a wild bird. The results indicate that food availability affects both hypothalamic and gonadal function, but further investigations are needed to clarify the mechanisms by which nutritional signals mediate these effects.

  9. House finch responses to Mycoplasma gallisepticum infection do not vary with experimentally increased aggression.

    PubMed

    Adelman, James Stephen; Moore, Ignacio Tomás; Hawley, Dana Michelle

    2015-01-01

    Aggression can alter infectious disease dynamics through two, non-exclusive mechanisms: 1) increasing direct contact among hosts and 2) altering hosts' physiological response to pathogens. Here we examined the latter mechanism in a social songbird by manipulating intraspecific aggression in the absence of direct physical contact. We asked whether the extent of aggression an individual experiences alters glucocorticoid levels, androgen levels, and individual responses to infection in an ecologically relevant disease model: house finches (Haemorhous mexicanus) infected with Mycoplasma gallisepticum (MG). Wild-caught male finches were housed in one of three settings, designed to produce increasing levels of aggression: 1) alone, with no neighbor ("no neighbor"), 2) next to a sham-implanted stimulus male ("sham neighbor"), or 3) next to a testosterone-implanted stimulus male ("testosterone neighbor"). Following one week of social treatment, focal males were experimentally infected with MG, which causes severe conjunctivitis and induces sickness behaviors such as lethargy and anorexia. While social treatment increased aggression as predicted, there were no differences among groups in baseline corticosterone levels, total circulating androgens, or responses to infection. Across all focal individuals regardless of social treatment, pre-infection baseline corticosterone levels were negatively associated with the severity of conjunctivitis and sickness behaviors, suggesting that corticosterone may dampen inflammatory responses in this host-pathogen system. However, because corticosterone levels differed based upon population of origin, caution must be taken in interpreting this result. Taken together, these results suggest that in captivity, although aggression does not alter individual responses to MG, corticosterone may play a role in this disease.

  10. Secondary Magnetization of ZEBRA Dolomites in the Basin and Range Province of Eastern Nevada

    NASA Astrophysics Data System (ADS)

    Elmore, R. D.; Dulin, S. A.

    2013-12-01

    Zebra dolomites within the Devonian Guilmette Formation of the southern Basin and Range Province, Nevada, are the focus of a paleomagnetic study to determine if a characteristic magnetization exists that will yield insight into the timing of zebra dolomite formation. Zebra dolomites consist of alternating bands of light and dark dolomite, and are found throughout Nevada, often associated with mineralized ore deposits. Although a variety of mechanisms have been suggested for formation, the zebra dolomite throughout Nevada is likely associated with hydrothermal fluid migration. The current study focuses on zebra dolomites that have formed in close stratigraphic proximity and within the Alamo Breccia in the Delamar Range in southeastern Nevada. The Alamo Breccia is an impact generated mega-breccia zone within the Devonian Guilmette Formation. The zebra dolomites, including those in the Alamo Breccia, and host Guilmette in the Delamar Range have a characteristic remanent magnetization (ChRM) with maximum laboratory unblocking temperatures of 480°C that is interpreted to reside in magnetite. The rocks were structurally rotated to remove Cenozoic extension, and the stratigraphic mean direction of the ChRM has a declination of 164.4°, with an inclination of -3°. The calculated pole is at 51.6°N, 90.7°E (dp = 2.2, dm = 4.3) which lies near the late Triassic portion of the apparent polar wander path (APWP) for North America. Based on low burial temperatures, this ChRM is interpreted as a chemical remanent magnetization (CRM) that was acquired due to the mobilization of brines possibly associated with the Triassic Sonoma orogeny. Geochemical data are consistent with alteration by externally derived fluids. The presence of a late Triassic magnetization indicates that the zebra dolomite can be no younger than Late Triassic. Preliminary results from zebra dolomites in other areas in southeastern Nevada indicate a more complex magnetization; some locations contain both

  11. Cryptosporidium parvum oocysts in zebra mussels (Dreissena polymorpha): evidence from the St Lawrence River.

    PubMed

    Graczyk, T K; Marcogliese, D J; de Lafontaine, Y; Da Silva, A J; Mhangami-Ruwende, B; Pieniazek, N J

    2001-03-01

    Molluscan shellfish can recover and concentrate environmentally derived waterborne pathogens and can be used for the sanitary assessment of water quality. Oocysts of Cryptosporidium parvum (genotype 1) were identified in zebra mussels (Dreissena polymorpha) from the St. Lawrence River, Quebec. Approximately 67 oocysts/ml of hemolymph and 129 oocysts/g of soft tissue were recovered. The adjusted concentration of oocysts per gram of tissue was 2.2 x 10(2), and approximately 4.4 x 10(2) oocysts were recovered from a single mussel. Zebra mussels can serve as biological indicators of waterborne contamination with Cryptosporidium.

  12. The ZEBRA electric vehicle battery: power and energy improvements

    NASA Astrophysics Data System (ADS)

    Galloway, Roy C.; Haslam, Steven

    Vehicle trials with the first sodium/nickel chloride ZEBRA batteries indicated that the pulse power capability of the battery needed to be improved towards the end of the discharge. A research programme led to several design changes to improve the cell which, in combination, have improved the power of the battery to greater than 150 W kg -1 at 80% depth of discharge. Bench and vehicle tests have established the stability of the high power battery over several years of cycling. The gravimetric energy density of the first generation of cells was less than 100 Wh kg -1. Optimisation of the design has led to a cell with a specific energy of 120 Wh kg -1 or 86 Wh kg -1 for a 30 kWh battery. Recently, the cell chemistry has been altered to improve the useful capacity. The cell is assembled in the over-discharged state and during the first charge the following reactions occur: at 1.6 V: Al+4NaCl=NaAlCl 4+3Na; at 2.35 V: Fe+2NaCl=FeCl 2+2Na; at 2.58 V: Ni+2NaCl=NiCl 2+2 Na. The first reaction serves to prime the negative sodium electrode but occurs at too low a voltage to be of use in providing useful capacity. By minimising the aluminium content more NaCl is released for the main reactions to improve the capacity of the cell. This, and further composition optimisation, have resulted in cells with specific energies in excess of 140 Wh kg -1, which equates to battery energies>100 Wh kg -1. The present production battery, as installed in a Mercedes Benz A class electric vehicle, gives a driving range of 205 km (128 miles) in city and hill climbing. The cells with improved capacity will extend the practical driving range to beyond 240 km (150 miles).

  13. Review of techniques to prevent introduction of zebra mussels (Dreissena polymorpha) during native mussel (Unionoidea) conservation activities

    USGS Publications Warehouse

    Cope, W.G.; Newton, T.J.; Gatenby, C.M.

    2003-01-01

    Because of the declines in diversity and abundance of native freshwater mussels (superfamily Unionoidea), and the potential decimation of populations of native mussels resulting from the rapid spread of the exotic zebra mussel Dreissena polymorpha, management options to eliminate or reduce the threat of the zebra mussel are needed. Relocating native mussels to refugia (artificial and natural) has been proposed to mitigate the threat of zebra mussels to native species. Relocation of native mussels to refugia such as fish hatchery facilities or natural habitats within their historic range. Which are unlikely to be infested by zebra mussels, necessitates that protocols be developed to prevent the inadvertent introduction of zebra mussels. Several recent studies have developed Such protocols, and have assessed their effectiveness on the health and survival of native mussels during subsequent relocation to various refugia. The purpose of this project is to synthesize and evaluate the current protocols and to develop a set of procedures that resource managers and researchers should consider before conducting conservation activities in zebra mussel infested waters. We found that the existing protocols have many common points of concern, such as facility modification and suitability, zebra mussel risk assessment and management procedures, and health and disease management procedures. These conservation protocols may have broad applicability to other situations and locations. A summary and evaluation of the information in these main areas, along with recommended guidelines, are presented in this article.

  14. Efficacy of Pseudomonas fluorescens (Pf-CL145A) spray dried powder for controlling zebra mussels adhering to test substrates

    USGS Publications Warehouse

    Luoma, James A.; Severson, Todd J.; Weber, Kerry L.; Mayer, Denise A.

    2015-01-01

    Approximately 30 days after exposure, zebra mussels were sorted into live and dead, and enumerated. Mean survival of zebra mussels in control treatments exceeded 95 percent. Mean survival of zebra mussels in the Lake Carlos WWC SDP-treated groups ranged from 0.5 to 2.1 percent and when compared at the same exposure duration, no difference was detected in survival between the 50 and 100 milligrams per liter (mg/L) treatment groups. Similarly, mean survival of zebra mussels in the Shawano Lake WWC SDP-treated groups ranged from 2.0 to 12.6 percent and when compared at the same exposure duration, no difference was detected in survival between the 50- and 100-mg/L treatment groups. Mean survival of zebra mussels in the Lake Carlos BI trial SDP-treated groups did not differ (p = 0.93) and was 18.1 and 18.0 percent in the 50- and 100-mg/L treatment groups, respectively. Mean survival of zebra mussels in the Shawano Lake BI trial SDP-treated groups differed (p < 0.01) and was 2.9 and 0.9 percent in the 50- and 100-mg/L treatment groups, respectively. Survival of zebra mussels assigned to the SDP-treated groups in the Lake Carlos WWC trial (12-hour exposure duration) differed from the survival of zebra mussels assigned to the SDP-treated groups in the Lake Carlos BI trial; however, after modification of the BI application technique, no difference (p = 0.22) was detected between the survival of zebra mussel in the Shawano Lake WWC (12-hour exposure duration) and BI trials.

  15. The Relationship between Plants Used to Sustain Finches (Fringillidae) and Uses for Human Medicine in Southeast Spain.

    PubMed

    Belda, Antonio; Peiró, Victoriano; Seva, Eduardo

    2012-01-01

    We analyzed plants that are traditionally used by wild bird hunters and breeders to capture and promote captive breeding of Fringillidae (finches or songbirds) in the province of Alicante, Spain. The majority of plants used in songbird breeding have medicinal properties in traditional human medicine (48 different uses); thus, another main goal was to show their relationships with human medical uses. We compiled a list of 97 plant species from 31 botanical families that are used to attract finches and identified 11 different use categories for these plants in finch keeping. The most common uses were for trapping birds and as a source of food for birds in captivity. Cannabis sativa has the greatest cultural importance index (CI = 1.158), and Phalaris canariensis (annual canary grass or alpist) was the most common species used to attract Fringillidae and was used by all informants (n = 158). Most of the 97 species are wild plants and mainly belong to the families Compositae, Gramineae, Cruciferae, and Rosaceae and also have medicinal properties for humans. In the study area, the intensification of agriculture and abandonment of traditional management practices have caused the population of many songbirds to decline, as well as the loss of popular ethnographic knowledge. PMID:22611428

  16. The Relationship between Plants Used to Sustain Finches (Fringillidae) and Uses for Human Medicine in Southeast Spain

    PubMed Central

    Belda, Antonio; Peiró, Victoriano; Seva, Eduardo

    2012-01-01

    We analyzed plants that are traditionally used by wild bird hunters and breeders to capture and promote captive breeding of Fringillidae (finches or songbirds) in the province of Alicante, Spain. The majority of plants used in songbird breeding have medicinal properties in traditional human medicine (48 different uses); thus, another main goal was to show their relationships with human medical uses. We compiled a list of 97 plant species from 31 botanical families that are used to attract finches and identified 11 different use categories for these plants in finch keeping. The most common uses were for trapping birds and as a source of food for birds in captivity. Cannabis sativa has the greatest cultural importance index (CI = 1.158), and Phalaris canariensis (annual canary grass or alpist) was the most common species used to attract Fringillidae and was used by all informants (n = 158). Most of the 97 species are wild plants and mainly belong to the families Compositae, Gramineae, Cruciferae, and Rosaceae and also have medicinal properties for humans. In the study area, the intensification of agriculture and abandonment of traditional management practices have caused the population of many songbirds to decline, as well as the loss of popular ethnographic knowledge. PMID:22611428

  17. Development of a molecular diagnostic system to discriminate Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel)

    USGS Publications Warehouse

    Hoy, M.S.; Kelly, K.; Rodriguez, R.J.

    2010-01-01

    A 3-primer PCR system was developed to discriminate invasive zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel. The system is based on: 1) universal primers that amplifies a region of the nuclear 28s rDNA gene from both species and 2) a species-specific primer complementary to either zebra or quagga mussel. The species-specific primers bind to sequences between the binding sites for the universal primers resulting in the amplification of two products from the target species and one product from the nontarget species. Therefore, nontarget products are positive amplification controls. The 3-primer system accurately discriminated zebra and quagga mussels from seven geographically distinct populations.

  18. Removal of enteric viruses and Escherichia coli from municipal treated effluent by zebra mussels.

    PubMed

    Mezzanotte, Valeria; Marazzi, Francesca; Bissa, Massimiliano; Pacchioni, Sole; Binelli, Andrea; Parolini, Marco; Magni, Stefano; Ruggeri, Franco M; De Giuli Morghen, Carlo; Zanotto, Carlo; Radaelli, Antonia

    2016-01-01

    Dreissena polymorpha is a widespread filter-feeder species, resistant to a broad range of environmental conditions and different types of pollutants,which has recently colonized Italian freshwaters. Although widely used to monitor pollution in freshwater environments, this species is also an important food source for some fish and water birds. It can also be used to concentrate or remove particulate organic matter to interrupt avian-to-human transmission of pollutants and control health risks for animals and humans. In this study, the accumulation/inactivation in D. polymorpha of human health-related spiked enteric viruses was described. The removal of endogenous Escherichia coli, the classical indicator of fecal contamination,was tested as well.Our preliminary lab-scale results demonstrate that zebra mussels can reduce significantly poliovirus titer after 24 h and rotavirus titer after 8 h. E. coli counts were also reduced in the presence of zebra mussels by about 1.5 log after 4 h and nearly completely after 24 h. The fate of the two enteric viruses after concentration by zebra mussels was also investigated after mechanical disruption of the tissues. To our knowledge, the accumulation from water and inactivation of human health-related enteric viruses by zebra mussels has never been reported. PMID:26372942

  19. Bindweed Psyllid: Biology, Natural History, and Interactions with the Zebra Chip Pathogen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bactericera maculipennis is a native psyllid that commonly occurs on field bindweed in the western United States. We have found that Pacific Northwest populations of B. maculipennis carry Liberibacter solanacearum, the pathogen associated with zebra chip disease of potato. In North America, this p...

  20. Variations in Zebra Chip disease expression and tuber biochemistry in response to vector density

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined effects of the number of ‘Candidatus Liberibacter solanacearum’ (Lso)-positive psyllids feeding on potatoes to Lso titers, zebra chip disease (ZC) symptom severity, and levels of amino acids, carbohydrates, and phenolics in tubers harvested weeks later. Red La Soda and Russet Nor...

  1. Zebra Chip: What is the risk of disease transmission through potato tubers?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zebra chip disease of potato is an economically devastating disease that causes a reduction in quality and quantity of tubers produced, and has affected growers in the United States, Mexico, Central America, and New Zealand. In an effort to determine if disease transmission can occur through fresh ...

  2. Potato psyllids and their bacterial allies: Two fronts in the war against zebra chip disease.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato psyllid is a major pest of potato in the western United States that transmits the pathogen that causes zebra chip disease. Potato psyllids, like all psyllids, have close associations with bacterial endosymbionts living within them. These endosymbionts may be obligate or facultative, and the...

  3. Equid herpesvirus 9 (EHV-9) isolates from zebras in Ontario, Canada, 1989 to 2007

    PubMed Central

    Rebelo, Ana Rita; Carman, Susy; Shapiro, Jan; van Dreumel, Tony; Hazlett, Murray; Nagy, Éva

    2015-01-01

    The objective of this study was to identify and partially characterize 3 equid herpesviruses that were isolated postmortem from zebras in Ontario, Canada in 1989, 2002, and 2007. These 3 virus isolates were characterized by plaque morphology, restriction fragment length polymorphism (RFLP) of their genomic deoxyribonucleic acid (DNA), real-time polymerase chain reaction (PCR) assay, and sequence analyses of the full length of the glycoprotein G (gG) gene (ORF70) and a portion of the DNA polymerase gene (ORF30). The isolates were also compared to 3 reference strains of equid herpesvirus 1 (EHV-1). Using rabbit kidney cells, the plaques for the isolates from the zebras were found to be much larger in size than the EHV-1 reference strains. The RFLP patterns of the zebra viruses differed among each other and from those of the EHV-1 reference strains. Real-time PCR and sequence analysis of a portion of the DNA polymerase gene determined that the herpesvirus isolates from the zebras contained a G at nucleotide 2254 and a corresponding N at amino acid position 752, which suggested that they could be neuropathogenic EHV-1 strains. However, subsequent phylogenetic analysis of the gG gene suggested that they were EHV-9 and not EHV-1. PMID:25852233

  4. ZEBRA MUSSEL COLONIZATION OF RUSTY CRAYFISH IN GREEN BAY, LAKE MICHIGAN

    EPA Science Inventory

    In August, 1995 six rusty crayfish colonized with zebra mussels were captured in small-meshed fyke-nets sets set apart as of a fish sampling effort at Peter's Marsh and Long-Tail Point Wetland in lower Green Bay. Mussels colonized virtually all areas of the crayfish bodies, but ...

  5. Assessing the potential for fish predation to impact zebra mussels (Dreissena polymorpha): Insight from bioenergetics models

    USGS Publications Warehouse

    Eggleton, M.A.; Miranda, L.E.; Kirk, J.P.

    2004-01-01

    Rates of annual food consumption and biomass were modeled for several fish species across representative rivers and lakes in eastern North America. Results were combined to assess the relative potential of fish predation to impact zebra mussels (Dreissena polymorpha). Predicted annual food consumption by fishes in southern waters was over 100% greater than that in northern systems because of warmer annual water temperatures and presumed increases in metabolic demand. Although generally increasing with latitude, biomasses of several key zebra mussel fish predators did not change significantly across latitudes. Biomasses of some less abundant fish predators did increase significantly with latitude, but increases were not of the magnitude to offset predicted decreases in food consumption. Our results generally support the premise that fishes in rivers and lakes of the southern United States (U.S.) have inherently greater potential to impact zebra mussels by predation. Our simulations may provide a partial explanation of why zebra mussel invasions have not been as rapid and widespread in southern U.S. waters compared to the Great Lakes region. ?? Blackwell Munksgaard, 2004.

  6. SPATIALLY AND SPECTRALLY RESOLVED OBSERVATIONS OF A ZEBRA PATTERN IN A SOLAR DECIMETRIC RADIO BURST

    SciTech Connect

    Chen Bin; Bastian, T. S.; Gary, D. E.; Jing Ju

    2011-07-20

    We present the first interferometric observation of a zebra-pattern radio burst with simultaneous high spectral ({approx}1 MHz) and high time (20 ms) resolution. The Frequency-Agile Solar Radiotelescope Subsystem Testbed (FST) and the Owens Valley Solar Array (OVSA) were used in parallel to observe the X1.5 flare on 2006 December 14. By using OVSA to calibrate the FST, the source position of the zebra pattern can be located on the solar disk. With the help of multi-wavelength observations and a nonlinear force-free field extrapolation, the zebra source is explored in relation to the magnetic field configuration. New constraints are placed on the source size and position as a function of frequency and time. We conclude that the zebra burst is consistent with a double-plasma resonance model in which the radio emission occurs in resonance layers where the upper-hybrid frequency is harmonically related to the electron cyclotron frequency in a coronal magnetic loop.

  7. Zebra mussel antifouling activity of the marine natural product aaptamine and analogs.

    PubMed

    Diers, Jeffrey A; Bowling, John J; Duke, Stephen O; Wahyuono, Subagus; Kelly, Michelle; Hamann, Mark T

    2006-01-01

    Several aaptamine derivatives were selected as potential zebra mussel (Dreissena polymorpha) antifoulants because of the noteworthy absence of fouling observed on Aaptos sponges. Sponges of the genus Aaptos collected in Manado, Indonesia consistently produce aaptamine-type alkaloids. To date, aaptamine and its derivatives have not been carefully evaluated for their antifoulant properties. Structure-activity relationship studies were conducted using several aaptamine derivatives in a zebra mussel antifouling assay. From these data, three analogs have shown significant antifouling activity against zebra mussel attachment. Aaptamine, isoaaptamine, and the demethylated aaptamine compounds used in the zebra mussel assay produced EC(50) values of 24.2, 11.6, and 18.6 microM, respectively. In addition, neither aaptamine nor isoaaptamine produced a phytotoxic response (as high as 300 microM) toward a nontarget organism, Lemna pausicostata, in a 7-day exposure. The use of these aaptamine derivatives from Aaptos sp. as potential environmentally benign antifouling alternatives to metal-based paints and preservatives is significant, not only as a possible control of fouling organisms, but also to highlight the ecological importance of these and similar biochemical defenses.

  8. Zebra Mussel Antifouling Activity of the Marine Natural Product Aaptamine and Analogs

    PubMed Central

    Diers, Jeffrey A.; Bowling, John J.; Duke, Stephen O.; Wahyuono, Subagus; Kelly, Michelle; Hamann, Mark T.

    2016-01-01

    Several aaptamine derivatives were selected as potential zebra mussel (Dreissena polymorpha) antifoulants because of the noteworthy absence of fouling observed on Aaptos sponges. Sponges of the genus Aaptos collected in Manado, Indonesia consistently produce aaptamine-type alkaloids. To date, aaptamine and its derivatives have not been carefully evaluated for their antifoulant properties. Structure–activity relationship studies were conducted using several aaptamine derivatives in a zebra mussel antifouling assay. From these data, three analogs have shown significant antifouling activity against zebra mussel attachment. Aaptamine, isoaaptamine, and the demethylated aaptamine compounds used in the zebra mussel assay produced EC50 values of 24.2, 11.6, and 18.6 μM, respectively. In addition, neither aaptamine nor isoaaptamine produced a phytotoxic response (as high as 300 μM) toward a nontarget organism, Lemna pausicostata, in a 7-day exposure. The use of these aaptamine derivatives from Aaptos sp. as potential environmentally benign antifouling alternatives to metal-based paints and preservatives is significant, not only as a possible control of fouling organisms, but also to highlight the ecological importance of these and similar biochemical defenses. PMID:16718618

  9. Evaluation of several chemical disinfectants for removing zebra mussels from unionid mussels

    USGS Publications Warehouse

    Waller, D.L.; Fisher, S.W.

    1998-01-01

    We evaluated the safety and effectiveness of chemical treatments for killing veliger and juvenile stages of the zebra mussel Dreissena polymorpha attached to unionid mussels. Static toxicity tests were conducted on eight unionid mussel species with common aquaculture chemicals (benzalkonium chloride, formalin, hydrogen peroxide, calcium chloride, potassium chloride, and sodium chloride). The concentration and duration of each chemical treatment tested had previously been found to kill zebra mussel veligers and juveniles. Several species (e.g., Elliptio dilatata, Lampsilis cardium, and Lasmigona complanata) incurred less than 10% mortality in chloride salt treatments, while in other species (e.g., Obliquaria reflexa and Leptodea fragilis) mortality varied greatly among treatment regimes. Treatments with benzalkonium chloride, formalin, and hydrogen peroxide were less than 90% effective on juvenile stages of zebra mussels and, therefore, were ruled out after preliminary trials. Limited application of specific chemical treatments may be feasible for more tolerant species; however, effective disinfection of unionid shells will require the use of chemical treatment followed by a quarantine period to completely remove zebra mussel larvae and juveniles.

  10. Examining the role of tuber biochemistry in the development of zebra chip in stored potato tubers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Zebra chip disease (ZC), associated with infection by the bacterium ‘Candidatus Liberibacter solanacearum’ (Lso), is an emerging problem for potato growers in the United States, Mexico, and New Zealand. Although potato tubers exhibiting ZC symptoms will be rejected by processors, it remains possible...

  11. DNA damage and effects on antioxidative enzymes in zebra fish (Danio rerio) induced by atrazine.

    PubMed

    Zhu, Lu-Sheng; Shao, Bo; Song, Yan; Xie, Hui; Wang, Jun; Wang, Jin-Hua; Liu, Wei; Hou, Xin-Xin

    2011-01-01

    The effect of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1, 3, 5-triazine) on the activity of some antioxidative enzymes (superoxide dismutase, SOD; catalase, CAT; and guaiacol peroxidase, POD) and DNA damage induced by atrazine were investigated in zebra fish (Danio rerio). Zebra fish were exposed to four different concentrations of atrazine (0, 2.5, 5, and 10 mg/L) for 7, 14, and 21 days, with three replicates of 10 fishes per treatment. Compared to the controls, the SOD activity in the 2.5 mg/L treatment was markedly stimulated in 21 days, while the SOD activities in the 5 mg/L treatment was stimulated at first and then inhibited. The change of CAT activity at 2.5 mg/L was similar to the SOD activity at 2.5 mg/L. The POD activities in the 2.5, 5, and 10 mg/L treatment were markedly higher on days 14 and 21 compared with the controls. The olive tail moments of single-cell gel electrophoresis (SCGE) of zebra fish enhanced after treatment of different doses on days 7, 14, and 21, and significant differences were found compared to the controls. In conclusion, these findings showed the effect regularity of atrazine to zebra fish, and also provide the basis for the future research of adverse effects induced by atrazine in aquatic ecosystems.

  12. Non-destructive NIR detection of Zebra Chip disease in w