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- Shrews (2)
- Sigmodon hispidus (2)
- Southern bog lemming (2)
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Articles 1 - 30 of 47
Full-Text Articles in Animal Sciences
Monitoring Extinction Risk And Threats Of The World's Fishes Based On The Sampled Red List Index, Rafael Miranda, Imanol Miqueleiz, William Darwall, Catherine Sayer, Nicholas K. Dulvy, Kent E. Carpenter, Beth Polidoro, Nadia Dewhurst-Richman, Caroline Pollock, Craig Hilton-Taylor, Robin Freeman, Ben Collen, Monika Böhm
Monitoring Extinction Risk And Threats Of The World's Fishes Based On The Sampled Red List Index, Rafael Miranda, Imanol Miqueleiz, William Darwall, Catherine Sayer, Nicholas K. Dulvy, Kent E. Carpenter, Beth Polidoro, Nadia Dewhurst-Richman, Caroline Pollock, Craig Hilton-Taylor, Robin Freeman, Ben Collen, Monika Böhm
Biological Sciences Faculty Publications
Global biodiversitytargets require us to identify species at risk of extinction and quantify status and trends of biodiversity. The Red List Index (RLI) tracks trends in the conservation status of entire species groups over time by monitoring changes in categories assigned to species. Here, we calculate this index for the world’s fishes in 2010, using a sampled approach to the RLI based on a randomly selected sample of 1,500 species, and also present RLI splits for freshwater and marine systems separately. We further compare specific traits of a worldwide fish list to our sample to assess its representativeness. Overall, 15.1% …
The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David
The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David
Biological Sciences Faculty Publications
Many wildlife species are live captured, sampled, and released; for polar bears (Ursus maritimus) capture often requires chemical immobilization via helicopter darting. Polar bears reduce their activity for approximately 4 days after capture, likely reflecting stress recovery. To better understand this stress, we quantified polar bear activity (via collar‐mounted accelerometers) and body temperature (via loggers in the body core [Tabd] and periphery [Tper]) during 2–6 months of natural behavior, and during helicopter recapture and immobilization. Recapture induced bouts of peak activity higher than those that occurred during natural behavior for 2 of 5 bears, …
Significance Of Autumn And Winter Food Consumption For Reproduction By Southern Beaufort Sea Polar Bears, Ursus Maritimus, Blaine D. Griffen, John P. Whiteman, Sariah Pullan
Significance Of Autumn And Winter Food Consumption For Reproduction By Southern Beaufort Sea Polar Bears, Ursus Maritimus, Blaine D. Griffen, John P. Whiteman, Sariah Pullan
Biological Sciences Faculty Publications
Polar bears (Ursus maritimus) in the southern Beaufort Sea experience long annual periods when preferred seal prey are scarce or are unavailable. Consumption of bowhead whale (Balaena mysticetus) carcasses from native Alaskan subsistence hunting is increasingly common for onshore polar bears, yet the energetic consequences of this consumption remain unclear. We use data on bears captured repeatedly over periods that encompassed autumn and winter, combined with calculations, to show that adult female bears likely consume an average of at least 4 seal equivalents during both autumn and winter periods and that considerable variation in energy intake …
Global Extinction Risk For Seahorses, Pipefishes And Their Near Relatives (Syngnathiformes), Riley A. Pollom, Gina M. Ralph, Caroline M. Pollock, Amanda C.J. Vincent
Global Extinction Risk For Seahorses, Pipefishes And Their Near Relatives (Syngnathiformes), Riley A. Pollom, Gina M. Ralph, Caroline M. Pollock, Amanda C.J. Vincent
Biological Sciences Faculty Publications
Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are …
Scaling The Effects Of Ocean Acidification On Coral Growth And Coral-Coral Competition On Coral Community Recovery, Nicolas R. Evensen, Yves-Marie Bozec, Peter J. Edmunds, Peter J. Mumby
Scaling The Effects Of Ocean Acidification On Coral Growth And Coral-Coral Competition On Coral Community Recovery, Nicolas R. Evensen, Yves-Marie Bozec, Peter J. Edmunds, Peter J. Mumby
Biological Sciences Faculty Publications
Ocean acidification (OA) is negatively affecting calcification in a wide variety of marine organisms. These effects are acute for many tropical scleractinian corals under short-term experimental conditions, but it is unclear how these effects interact with ecological processes, such as competition for space, to impact coral communities over multiple years. This study sought to test the use of individual-based models (IBMs) as a tool to scale up the effects of OA recorded in short-term studies to community-scale impacts, combining data from field surveys and mesocosm experiments to parameterize an IBM of coral community recovery on the fore reef of Moorea, …
The Natural History Of The Marsh Rice Rat, Oryzomys Palustris, In Eastern Virginia, Robert K. Rose
The Natural History Of The Marsh Rice Rat, Oryzomys Palustris, In Eastern Virginia, Robert K. Rose
Biological Sciences Faculty Publications
The marsh rice rat, Oryzomys palustris, is a common rodent in tidal marshes of eastern Virginia, including those on the barrier islands. It also is present in grassy old fields in upland habitats in the coastal plain and parts of the piedmont of Virginia. This report summarizes what has been learned in recent decades about the population biology of this species in Virginia, including aspects of behavior, density, diet, distribution, genetics, habitats, mammal associates, and reproduction.
Insights Into The Feeding Behaviors And Biomechanics Of Varroa Destructor Mites On Honey Bee Pupae Using Electropenetrography And Histology, Andrew Y. Li, Steven C. Cook, Daniel E. Sonenshine, Francisco Pasada-Florez, Noble I.I. Noble, Joseph Mowery, Conner J. Gulbronson, Gary R. Bauchan
Insights Into The Feeding Behaviors And Biomechanics Of Varroa Destructor Mites On Honey Bee Pupae Using Electropenetrography And Histology, Andrew Y. Li, Steven C. Cook, Daniel E. Sonenshine, Francisco Pasada-Florez, Noble I.I. Noble, Joseph Mowery, Conner J. Gulbronson, Gary R. Bauchan
Biological Sciences Faculty Publications
Feeding behaviors and biomechanics of female Varroa destructor mites are revealed from AC-DC electropenetrography (EPG) recordings of mites feeding from Apis mellifera honey bee pupae and histology of mite internal ingestion apparatus. EPG signals characteristic of arthropod suction feeding (ingestion) were identified for mites that fed on pupae during overnight recordings. Ingestion by these mites was confirmed afterwards by observing internally fluorescent microbeads previously injected into their hosts. Micrographs of internal ingestion apparatus illustrate the connection between a gnathosomal tube and a pharyngeal lumen, which is surrounded by alternating dilator and constrictor muscles. Inspection of EPG signals showed the muscularized …
Natural History Of The Eastern Harvest Mouse In Southeastern Virginia, Robert K. Rose
Natural History Of The Eastern Harvest Mouse In Southeastern Virginia, Robert K. Rose
Biological Sciences Faculty Publications
The Eastern Harvest Mouse, Reithrodontomys humulis, has been studied extensively in southeastern Virginia since 1979, using a combination of live and pitfall trapping methods. This smallest rodent of eastern North America also is one of most versatile, occupying a range of habitats in southeastern Virginia from old fields in different stages of succession, brushy edges, and forests of different types. As with other species of Reithrodontomys, R. humulis often is associated with the Hispid Cotton Rat, Sigmodon hispidus, with both reaching modest densities in old fields. Two capture-mark-release studies of small mammal communities in southern Chesapeake lasting …
Natural History Of The Southern Bog Lemming In Southeastern Virginia, Robert K. Rose
Natural History Of The Southern Bog Lemming In Southeastern Virginia, Robert K. Rose
Biological Sciences Faculty Publications
The isolated subspecies of Southern Bog Lemming of southeastern Virginia, Synaptomys cooperi helaletes, has been studied extensively since its "rediscovery" in the Great Dismal Swamp in 1980. Multiple studies using pitfall traps, starting in the Great Dismal Swamp National Wildlife Refuge and then extending elsewhere in southeastern Virginia and adjacent northeastern North Carolina, have revealed lemmings to be much more widespread and often more common than previously believed, with their presence now confirmed as far west as Surry and Sussex counties, about 30 km east of Petersburg, Virginia. When present, lemmings often are among the most numerous members of …
Do Avian Blood Parasites Influence Hypoxia Physiology In A High Elevation Environment?, Farah Ishtiaq, Sahas Barve
Do Avian Blood Parasites Influence Hypoxia Physiology In A High Elevation Environment?, Farah Ishtiaq, Sahas Barve
Biological Sciences Faculty Publications
BACKGROUND: Montane birds which engage in elevational movements have evolved to cope with fluctuations in environmental hypoxia, through changes in physiological parameters associated with blood oxygen-carrying capacity such as haemoglobin concentration (Hb) and haematocrit (Hct). In particular, elevational migrants which winter at low elevations, encounter varying intensities of avian haemosporidian parasites as they traverse heterogeneous environments. Whilst high intensity parasite infections lead to anaemia, one can expect that the ability to cope with haemosporidian infections should be a key trait for elevational migrants that must be balanced against reducing the oxygen-carrying capacity of blood in response to high elevation. In …
Review: Application Of Tick Control Technologies For Blacklegged, Lone Star, And American Dog Ticks, Alexis White, Holly Gaff
Review: Application Of Tick Control Technologies For Blacklegged, Lone Star, And American Dog Ticks, Alexis White, Holly Gaff
Biological Sciences Faculty Publications
Tick population control technologies have been studied for several decades but no method is successful in all situations. The success of each technology depends on tick species identity and abundance, host species identity and abundance, phenology of both ticks and hosts, geographic region, and a multitude of other factors. Here we review current technologies, presenting an overview of each and its effect on three common tick species in the eastern United States: blacklegged ticks (Ixodes scapularis (Say; Ixodida: Ixodidae)), lone star ticks (Amblyomma americanum (Linnaeus; Ixodida: Ixodidae)), and American dog ticks (Dermacentor variabilis (Say; Ixodida: Ixodidae)). Moreover, …
Reproductive Competency And Mitochondrial Variation In Aged Syrian Hamster Oocytes, Fang Li, Frank J. Castora, Wentia Ford, Khalid Alarid, Howard W. Jones Jr., R. James Swanson
Reproductive Competency And Mitochondrial Variation In Aged Syrian Hamster Oocytes, Fang Li, Frank J. Castora, Wentia Ford, Khalid Alarid, Howard W. Jones Jr., R. James Swanson
Biological Sciences Faculty Publications
The hamster is a useful model of human reproductive biology because its oocytes are similar to those in humans in terms of size and structural stability. In the present study we evaluated fecundity rate, ovarian follicular numbers, ova production, mitochondrial number, structure and function, and cytoplasmic lamellae (CL) in young (2–4 months) and old (12–18 months) Syrian hamsters (Mesocricetus auratus). Young hamsters had higher fertilisation rates and larger litters than old hamsters (100 vs 50% and 9.3 +/- 0.6 vs 5.5 +/- 0.6, respectively). Ovarian tissue from superovulated animals showed a 46% decrease in preantral follicles in old …
Testing Alternative Hypotheses For The Cause Of Population Declines: The Case Of The Red-Headed Woodpecker, Walter D. Koenig, Eric L. Walters, Paul G. Rodewald
Testing Alternative Hypotheses For The Cause Of Population Declines: The Case Of The Red-Headed Woodpecker, Walter D. Koenig, Eric L. Walters, Paul G. Rodewald
Biological Sciences Faculty Publications
The Red-headed Woodpecker (Melanerpes erythrocephalus) has experienced strong population declines during the past 3 decades. Using North American Breeding Bird Survey (BBS) and Audubon Christmas Bird Count (CBC) data, we investigated 4 hypotheses that may explain this decline, including: (1) interspecific competition with native Red-bellied Woodpeckers (Melanerpes carolinus) and nonnative European Starlings (Sturnus vulgaris); (2) predation by Cooper's Hawks (Accipiter cooperii) and Sharp-shinned Hawks (Accipiter striatus); (3) climate change; and (4) changes in forested area within their range. In analyses of both the breeding and overwintering periods, our results indicated …
The Small Mammals Of Southeastern Virginia As Revealed By Pitfall Trapping, Robert K. Rose
The Small Mammals Of Southeastern Virginia As Revealed By Pitfall Trapping, Robert K. Rose
Biological Sciences Faculty Publications
Pitfall trapping is a poor method to catch small mammals but the only way to catch and study the Southeastern Shrew (Sorex longirostris), the primary mammal of interest in the field studies reported here. While learning much about its distribution and abundance, still more was learned about the other small mammals present in forests and fields of eastern Virginia. A total of 15 species was captured at 19 locations during the 1990-2013 period, including five shrews, two moles, and eight rodents, representing all but one of the common small mammals in eastern Virginia.
Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky
Diet And Foraging Behaviors Of Timber Rattlesnakes, Crotalus Horridus, In Eastern Virginia, Scott M. Goetz, Christopher E. Petersen, Robert K. Rose, John D. Kleopfer, Alan H. Savitzky
Biological Sciences Faculty Publications
During a 17-yr telemetry study, we examined the diet and ambush behavior of a population of Crotalus horridus in southeastern Virginia. Forty dietary items were identified from 37 fecal samples. We documented 722 instances of snakes in an ambush posture, 61 of which were in a vertical-tree posture, as if hunting arboreal prey at the base of a tree. The most common prey items were Eastern Gray Squirrels (Sciurus carolinensis), which accounted for 45 of all dietary items and represented an estimated 78 of total biomass consumed by C. horridus. Prey was not consumed in proportion to availability, …
Chemical Defense Of An Asian Snake Reflects Local Availability Of Toxic Prey And Hatchling Diet, D. A. Hutchinson, A. H. Savitzky, G. M. Burghardt, C. Nguyen, J. Meinwald, F. C. Schroeder, A. Mori
Chemical Defense Of An Asian Snake Reflects Local Availability Of Toxic Prey And Hatchling Diet, D. A. Hutchinson, A. H. Savitzky, G. M. Burghardt, C. Nguyen, J. Meinwald, F. C. Schroeder, A. Mori
Biological Sciences Faculty Publications
Species that sequester toxins from prey for their own defense against predators may exhibit population-level variation in their chemical arsenal that reflects the availability of chemically defended prey in their habitat. Rhabdophis tigrinus is an Asian snake that possesses defensive glands in the skin of its neck (nuchal glands'), which typically contain toxic bufadienolide steroids that the snakes sequester from consumed toads. In this study, we compared the chemistry of the nuchal gland fluid of R.tigrinus from toad-rich and toad-free islands in Japan and determined the effect of diet on the nuchal gland constituents. Our findings demonstrate that captive-hatched juveniles …
Unusually High Body Mass In Virginia Meadow Voles, Sara B. Longtin, Robert K. Rose
Unusually High Body Mass In Virginia Meadow Voles, Sara B. Longtin, Robert K. Rose
Biological Sciences Faculty Publications
We used monthly capture-mark-recapture information to determine growth rates and life spans for 2 populations of meadow voles studied for 28 and 29 months in eastern Virginia in order to learn whether the exceptionally large body masses of some voles were due to rapid growth, long lives, or both. On 1 study grid, 64 males (19%) and 43 nonpregnant females (11%) were ≥70 g, with the largest male being 89 g. Mostly positive growth rates (averaging 1.1-3.9 g/month) were recorded, even in autumn and winter months, times when meadow voles are losing mass in northern populations, where most studies of …
Effects Of Gypsy Moth Outbreaks On North American Woodpeckers, Walter D. Koenig, Eric L. Walters, Andrew M. Liebhold
Effects Of Gypsy Moth Outbreaks On North American Woodpeckers, Walter D. Koenig, Eric L. Walters, Andrew M. Liebhold
Biological Sciences Faculty Publications
We examined the effects of the introduced gypsy moth (Lymantria dispar) on seven species of North American woodpeckers by matching spatially explicit data on gypsy moth outbreaks with data on breeding and wintering populations. In general, we detected modest effects during outbreaks: during the breeding season one species, the Red-headed Woodpecker (Melanerpes erythrocephalus), increased over pre-outbreak levels, while during the winter one species, the Yellow-bellied Sapsucker (Sphyrapicus varius), increased and one, the Downy Woodpecker (Picoides pubescens), decreased from pre-outbreak levels. Responses following outbreaks were similarly variable, and in general we were unsuccessful …
Range Extension For The Dismal Swamp Southern Bog Lemming, Synaptomys Cooperi Helaletes, In Eastern Virginia, Robert K. Rose
Range Extension For The Dismal Swamp Southern Bog Lemming, Synaptomys Cooperi Helaletes, In Eastern Virginia, Robert K. Rose
Biological Sciences Faculty Publications
The distribution of the Dismal Swamp Southern Bog Lemming is extended to include three counties west of the Dismal Swamp in southeastern Virginia, long considered its only location in the state. Evidence of lemmings was detected at 10 of 27 survey sites, and confirmed by trapping at three of five sites, all dominated by herbaceous vegetation.
A New Species Of The Subterranean Amphipod Crustacean Genus Stygobromus (Crangonyctidae) From A Cave In Nevada, Usa, Steven J. Taylor, John R. Holsinger
A New Species Of The Subterranean Amphipod Crustacean Genus Stygobromus (Crangonyctidae) From A Cave In Nevada, Usa, Steven J. Taylor, John R. Holsinger
Biological Sciences Faculty Publications
Stygobromus albapinus, a new stygobiotic amphipod crustacean species in the family Crangonyctidae, is described from two pools in Model Cave in Great Basin National Park, White Pine County, Nevada, USA. The type specimens were collected on two different visits to the cave. The new species is assigned to the hubbsi group, bringing the number of described species in this group to 45, but many other provisionally recognized species assigned to this group remain undescribed. With exception of a single species from deep wells in southeastern Wisconsin, all other members of the hubbsi group are recorded from a wide variety …
The Impact Of Conservation On The Status Of The World's Vertebrates, Michael Hoffmann, Craig Hilton-Taylor, Ariadne Angulo, Monika Böhm, Thomas M. Brooks, Stuart H. M. Butchart, Kent E. Carpenter, Janice Chanson, Beth A. Polidoro, Jonnell C. Sanciangco
The Impact Of Conservation On The Status Of The World's Vertebrates, Michael Hoffmann, Craig Hilton-Taylor, Ariadne Angulo, Monika Böhm, Thomas M. Brooks, Stuart H. M. Butchart, Kent E. Carpenter, Janice Chanson, Beth A. Polidoro, Jonnell C. Sanciangco
Biological Sciences Faculty Publications
Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the …
Morphological Differences Among Eyeless Amphipods In The Genus Stygobromus Dwelling In Different Subterranean Habitats, David C. Culver, John R. Holsinger, Mary C. Christman, Tanja Pipan
Morphological Differences Among Eyeless Amphipods In The Genus Stygobromus Dwelling In Different Subterranean Habitats, David C. Culver, John R. Holsinger, Mary C. Christman, Tanja Pipan
Biological Sciences Faculty Publications
The amphipod genus Stygobromus occurs in a variety of subterranean habitats in North America, including caves, phreatic (groundwater) lakes, and superficial subterranean habitats (seeps and epikarst). The habitats share the absence of light but differ in other features, such as pore size of the habitat, available food, and degree of seasonality. Measurements of body size, antennal size, and antennal segment number of type specimens were compared for 56 species occurring in the eastern United States. Except for differences in body size, differences among species in the four different habitats were not significant. Body size was related to relative pore size …
Growth And Survival In A Northern Population Of Hispid Cotton Rats, Heather A. Green, Robert K. Rose
Growth And Survival In A Northern Population Of Hispid Cotton Rats, Heather A. Green, Robert K. Rose
Biological Sciences Faculty Publications
Using data from a 28-month capture–mark–recapture study that included 3 winters, we compared rates of body growth and survival for a population of hispid cotton rats (Sigmodon hispidus) in eastern Virginia with another marginal population in eastern Kansas, and where possible, with southern populations in coastal Texas and central Florida. Patterns of seasonal growth were similar in Virginia and Kansas, being low, often near 0, in winter but moderate in other seasons, unlike the uniform seasonal growth rates in Texas. Survival rates were similar between the sexes in both Virginia and Kansas but the overall monthly survival rate …
Population Ecology Of The Golden Mouse, Robert K. Rose
Population Ecology Of The Golden Mouse, Robert K. Rose
Biological Sciences Faculty Publications
An understanding of the population dynamics of a species requires knowledge of the major life-history parameters of a population, including age at maturity, distribution of age classes, and lifetime reproductive contribution of the sexes, sex ratio, length of the breeding season, mean litter size, rates of growth and survival, and life span. Because few long-term studies have been conducted with Ochrotomys nuttalli as the focal species of investigation, only fragmentary information is available for many population parameters. As importantly, densities of golden mice often are low, making them difficult to evaluate statistically. Little has been published on age at maturity …
Advancing Epidemiological Science Through Computational Modeling: A Review With Novel Examples, Scott M. Duke-Sylvester, Eli N. Perencevich, Jon P. Furuno, Leslie A. Real, Holly Gaff
Advancing Epidemiological Science Through Computational Modeling: A Review With Novel Examples, Scott M. Duke-Sylvester, Eli N. Perencevich, Jon P. Furuno, Leslie A. Real, Holly Gaff
Biological Sciences Faculty Publications
Computational models have been successfully applied to a wide variety of research areas including infectious disease epidemiology. Especially for questions that are difficult to examine in other ways, computational models have been used to extend the range of epidemiological issues that can be addressed, advance theoretical understanding of disease processes and help identify specific intervention strategies. We explore each of these contributions to epidemiology research through discussion and examples. We also describe in detail models for raccoon rabies and methicillin-resis-tant Staphylococcus aureus, drawn from our own research, to further illustrate the role of computation in epidemiological modeling.
Oviposition Behavior Partitions Aquatic Landscapes Along Predation And Nutrient Gradients, C. A. Binckley, W. J. Resetarits Jr.
Oviposition Behavior Partitions Aquatic Landscapes Along Predation And Nutrient Gradients, C. A. Binckley, W. J. Resetarits Jr.
Biological Sciences Faculty Publications
That individuals attempt to minimize the ratio of mortality risk/growth rate (μ/g) when foraging within individual habitat patches is well established. Do species partition among spatially discrete communities embedded in complex landscapes in a similar manner? We investigated how 3 ovipositing species (2 Hyla treefrogs and a hydrophilid beetle, Tropisternus lateralis) responded to simultaneous gradients of nutrients and predation risk. Species partitioned our experimental metacommunity primarily by reducing oviposition with fish. Tropisternus positively responded to increased nutrients, but the effect decreased with increasing risk, as predicted by μ/g theory. Use of fish habitats by Tropisternus was unrelated to breeding …
Swimming Dynamics And Propulsive Efficiency Of Squids Throughout Ontogeny, Ian K. Bartol, Paul S. Krueger, Joseph T. Thompson, William J. Stewart
Swimming Dynamics And Propulsive Efficiency Of Squids Throughout Ontogeny, Ian K. Bartol, Paul S. Krueger, Joseph T. Thompson, William J. Stewart
Biological Sciences Faculty Publications
Synopsis Squids encounter vastly different flow regimes throughout ontogeny as they undergo critical morphological changes to their two locomotive systems: the fins and jet. Squid hatchlings (paralarvae) operate at low and intermediate Reynolds numbers (Re) and typically have rounded bodies, small fins, and relatively large funnel apertures whereas juveniles and adults operate at higher Re and generally have more streamlined bodies, larger fins, and relatively small funnel apertures. These morphological changes and varying flow conditions affect swimming performance in squids. To determine how swimming dynamics and propulsive efficiency change throughout ontogeny, digital particle image velocimetry (DPIV) and kinematic …
Dietary Sequestration Of Defensive Steroids In Nuchal Glands Of The Asian Snake Rhabdophis Tigrinus, Deborah A. Hutchinson, Akira Mori, Alan H. Savitsky, Gordon M. Burghardt, Xiaogang Wu, Jerrold Meinwald, Frank C, Schroeder
Dietary Sequestration Of Defensive Steroids In Nuchal Glands Of The Asian Snake Rhabdophis Tigrinus, Deborah A. Hutchinson, Akira Mori, Alan H. Savitsky, Gordon M. Burghardt, Xiaogang Wu, Jerrold Meinwald, Frank C, Schroeder
Biological Sciences Faculty Publications
The Asian snake Rhabdophis tigrinus possesses specialized defensive glands on its neck that contain steroidal toxins known as bufadienolides. We hypothesized that R. tigrinus does not synthesize these defensive steroids but instead sequesters the toxins from toads it consumes as prey. To test this hypothesis, we conducted chemical analyses on the glandular fluid from snakes collected in toad-free and toad-present localities. We also performed feeding experiments in which hatchling R. tigrinus were reared on controlled diets that either included or lacked toads. We demonstrate that the cardiotonic steroids in the nuchal glands of R. tigrinus are obtained from dietary toads. …
The Adaptive Value Of Aggregation Among Juvenile Caribbean Spiny Lobster: An Evaluation Using Individual-Based Modeling, Thomas W. Dolan Iii, Mark J. Butler Iv
The Adaptive Value Of Aggregation Among Juvenile Caribbean Spiny Lobster: An Evaluation Using Individual-Based Modeling, Thomas W. Dolan Iii, Mark J. Butler Iv
Biological Sciences Faculty Publications
Ontogenetic changes in gregariousness by pre-reproductive animals, like that observed in juvenile Caribbean spiny lobsters (Panulirus argus), may be adaptive and reflect size-specific changes in the effectiveness of aggregation in promoting survival. Alternatively, aggregation may simply result from changes in the distribution or availability of suitable habitat structure, or from other behaviors that enhance survival. There are currently two hypotheses explaining the potential benefits of gregarious behavior in juvenile spiny lobsters, both of which focus on increasing survivorship by reducing predation pressure: the group benefit hypothesis and the guide hypothesis. The group benefit hypothesis argues that aggregations of …
New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe
New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe
Biological Sciences Faculty Publications
Three new species of Tegano are described, two from caves on Panglao Island, Bohol, Philippines, and one from a cave on Peleliu Island, Palau. Sriha vagabunda from Sri Lanka is reassigned to the genus Tegano based primarily on the high degree of similarity between Sriha vagabunda and species of Tegano and the fact that these species exhibit a great deal of variation in the reduction of the mandibular palp. A new species of Melita with characters intermediate between those defining the genera Abludomelita, Melita, and Paraniphargus is described from a spring on Guam. The characters of the new …