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Full-Text Articles in Life Sciences

Physico Chemical, Azhagu Raj Ramakrishnan Oct 2015

Physico Chemical, Azhagu Raj Ramakrishnan

Azhaguraj Ramakrishnan

No abstract provided.


High Prevalence Of Leucocytozoon Parasites In Nestling Northern Goshawks (Accipiter Gentilis) In The Northern Great Basin, U.S.A., Michelle I. Jeffries, Robert A. Miller, Michelle D. Laskowski, Jay D. Carlisle Sep 2015

High Prevalence Of Leucocytozoon Parasites In Nestling Northern Goshawks (Accipiter Gentilis) In The Northern Great Basin, U.S.A., Michelle I. Jeffries, Robert A. Miller, Michelle D. Laskowski, Jay D. Carlisle

Robert Miller

The Northern Goshawk (Accipiter gentilis) is currently listed as a sensitive species by the U.S.D.A. Forest Service. Previous research in our study area, the South Hills of the Minidoka Ranger District of the Sawtooth National Forest, Idaho, identified possible signs of parasite infections among the banded adult and nestling goshawks, which could influence their survival and breeding success. Therefore, we sought to quantify the prevalence and intensity of Leucocytozoon parasites among a sample of nestling goshawks in the South Hills during the 2012 breeding season. We sampled 27 nestlings from 12 nests for Leucocytozoon parasites by examining ...


A Re-Assessment Of Priority Amphibian Species Of Peru, Edgar Lehr, Laurence Jarvis, Ariadne Angulo, Alessandro Catenazzi, Rudolf Von May, Jason Brown, James Lewis Aug 2015

A Re-Assessment Of Priority Amphibian Species Of Peru, Edgar Lehr, Laurence Jarvis, Ariadne Angulo, Alessandro Catenazzi, Rudolf Von May, Jason Brown, James Lewis

Edgar Lehr

Peru supports approximately 588 amphibian species, of which 492 have been assessed on the IUCN Red List of Threatened Species. Of these, 111 are classified as Threatened, with 69 species classified as Critically Endangered or Endangered. In addition, 140 amphibian species remain Data Deficient. We re-assessed the conservation status of 38 amphibian species originally identified as potentially Threatened by von May et al. (2008), using the IUCN Red List Categories and Criteria. Fourteen species assessments changed as a result of re-assessment, of which eight changed from Data Deficient to Threatened; two changed from Data Deficient to Near Threatened and Least ...


Clinical Anesthesia And Analgesia In Fish, Lynne U. Sneddon Jul 2015

Clinical Anesthesia And Analgesia In Fish, Lynne U. Sneddon

Lynne Sneddon, PhD

Fish have become a popular experimental model and companion animal, and are also farmed and caught for food. Thus, surgical and invasive procedures in this animal group are common, and this review will focus on the anesthesia and analgesia of fish. A variety of anesthetic agents are commonly applied to fish via immersion. Correct dosing can result in effective anesthesia for acute procedures as well as loss of consciousness for surgical interventions. Dose and anesthetic agent vary between species of fish and are further confounded by a variety of physiological parameters (e.g., body weight, physiological stress) as well as ...


The Efficacy Of Three Types Of Analgesic Drugs In Reducing Pain In The Rainbow Trout, Oncorhynchus Mykiss, Jessica J. Mettam, Lois J. Oulton, Catherine R. Mccrohan, Lynne U. Sneddon Jul 2015

The Efficacy Of Three Types Of Analgesic Drugs In Reducing Pain In The Rainbow Trout, Oncorhynchus Mykiss, Jessica J. Mettam, Lois J. Oulton, Catherine R. Mccrohan, Lynne U. Sneddon

Lynne Sneddon, PhD

Recent research has shown the possibility of pain perception in fish; therefore, the use of analgesia or “painkillers” should be considered for invasive procedures. However, there is relatively little information on the effectiveness of analgesic drugs nor on the appropriate dose for fish. This study assessed the efficacy of three types of drug: an opioid, buprenorphine, a non-steroidal anti-inflammatory drug (NSAID), carprofen and a local anaesthetic, lidocaine. Each drug was tested at three doses on rainbow trout that were noxiously stimulated and the most effective dose was also given to fish experiencing no pain to investigate side-effects. Ventilation rate and ...


Diffusion Tensor Imaging Of Dolphin Brains Reveals Direct Auditory Pathway To Temporal Lobe, Gregory S. Berns, Peter F. Cook, Sean Foxley, Saad Jbabdi, Karla L. Miller, Lori Marino Jul 2015

Diffusion Tensor Imaging Of Dolphin Brains Reveals Direct Auditory Pathway To Temporal Lobe, Gregory S. Berns, Peter F. Cook, Sean Foxley, Saad Jbabdi, Karla L. Miller, Lori Marino

Lori Marino, Ph.D.

The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes’ auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this position induced by expansion of ‘associative0 regions in lateral and caudal directions. However, the precise location of the auditory cortex and its connections are still unknown. Here ...


Two Tickets To Paradise: Multiple Dispersal Events In The Founding Of Hoary Bat Populations In Hawai'i, Amy L. Russell, Corinna A. Pinzari, Maarten J. Vonhof, Kevin J. Olival, Frank J. Bonaccorso Jun 2015

Two Tickets To Paradise: Multiple Dispersal Events In The Founding Of Hoary Bat Populations In Hawai'i, Amy L. Russell, Corinna A. Pinzari, Maarten J. Vonhof, Kevin J. Olival, Frank J. Bonaccorso

Amy L. Russell

The Hawaiian islands are an extremely isolated oceanic archipelago, and their fauna has long served as models of dispersal in island biogeography. While molecular data have recently been applied to investigate the timing and origin of dispersal events for several animal groups including birds, insects, and snails, these questions have been largely unaddressed in Hawaii'i's only native terrestrial mammal, the Hawaiian hoary bat, Lasiurus cinereus semotus. Here, we use molecular data to test the hypotheses that (1) Hawaiian L. c. semotus originated via dispersal from North American populations of L. c. cinereus rather than from South American L ...


Relative Volume Of The Cerebellum In Dolphins And Comparison With Anthropoid Primates, L. Marino, James K. Rilling, Shinko K. Lin, Sam H. Ridgway Jun 2015

Relative Volume Of The Cerebellum In Dolphins And Comparison With Anthropoid Primates, L. Marino, James K. Rilling, Shinko K. Lin, Sam H. Ridgway

Lori Marino, PhD

According to the ‘developmental constraint hypothesis’ of comparative mammalian neuroanatomy, brain growth follows predictable allometric trends. Therefore, brain structures should scale to the entire brain in the same way across mammals. Evidence for a departure from this pattern for cerebellum volume has recently been reported among the anthropoid primates. One of the mammalian groups that has been neglected in tests of the ‘developmental constraint hypothesis’ is the cetaceans (dolphins, whales, and porpoises). Because many cetaceans possess relative brain sizes in the range of primates comparative tests of the ‘developmental constraint hypothesis’ across these two groups could help to delineate the ...


Spatial Patterns Of Road Mortality: Assessing Turtle Barrier Conservation Strategies, Dorothy Ives-Dewey, James Lewandowski May 2015

Spatial Patterns Of Road Mortality: Assessing Turtle Barrier Conservation Strategies, Dorothy Ives-Dewey, James Lewandowski

Dorothy Ives-Dewey

No abstract provided.


The Evolutionary History Of Cetacean Brain And Body Size, Stephen H. Montgomery, Jonathan H. Geisler, Michael R. Mcgowen, Charlotte Fox, Lori Marino, John Gatesy May 2015

The Evolutionary History Of Cetacean Brain And Body Size, Stephen H. Montgomery, Jonathan H. Geisler, Michael R. Mcgowen, Charlotte Fox, Lori Marino, John Gatesy

Lori Marino, PhD

Cetaceans rival primates in brain size relative to body size and include species with the largest brains and biggest bodies to have ever evolved. Cetaceans are remarkably diverse, varying in both phenotypes by several orders of magnitude, with notable differences between the two extant suborders, Mysticeti and Odontoceti.We analyzed the evolutionary history of brain and body mass, and relative brain size measured by the encephalization quotient (EQ), using a data set of extinct and extant taxa to capture temporal variation in the mode and direction of evolution. Our results suggest that cetacean brain and body mass evolved under strong ...


New Records Of Merriam’S Shrew (Sorex Merriami) From Western North Dakota, Michael J. Shaughnessy Jr., Neal Woodman Mar 2015

New Records Of Merriam’S Shrew (Sorex Merriami) From Western North Dakota, Michael J. Shaughnessy Jr., Neal Woodman

Neal Woodman

Despite having a broad geographic distribution, Merriam’s Shrew (Sorex merriami Dobson 1890) is known from a relatively few, widely-scattered localities. In North Dakota, the species was known from only a single poorly-preserved specimen collected in 1913 near Medora. We recently collected two new specimens of Merriam’s Shrew from Billings and McKenzie counties in the western quarter of the state. These specimens confirm the presence of S. merriami in North Dakota and better define the northeastern edge of the species’ distribution.


Who Invented The Mule Deer (Odocoileus Hemionus)? On The Authorship Of The Fraudulent 1812 Journal Of Charles Le Raye, Neal Woodman Mar 2015

Who Invented The Mule Deer (Odocoileus Hemionus)? On The Authorship Of The Fraudulent 1812 Journal Of Charles Le Raye, Neal Woodman

Neal Woodman

The captivity journal of Charles Le Raye was first published in 1812 as a chapter in A topographical description of the state of Ohio, Indiana Territory, and Louisiana, a volume authored anonymously by “a late officer in the U. S. Army”. Le Raye was purported to be a French Canadian fur trader who, as a captive of the Sioux, had travelled across broad portions of the Missouri and Yellowstone river drainages a few years before the Lewis and Clark expedition (1804–1806), and his account of the land, its people, and its natural resources was relied upon as a primary ...


Genetic Susceptibility To Chronic Wasting Disease In Free-Ranging White-Tailed Deer: Complement Component C1q And Prnp Polymorphisms, Julie A. Blanchong, Dennis M. Heisey, Kim T. Scribner, Scot V. Libants, Chad Johnson, Judd M. Aiken, Julia A. Langenberg, Michael D. Samuel Mar 2015

Genetic Susceptibility To Chronic Wasting Disease In Free-Ranging White-Tailed Deer: Complement Component C1q And Prnp Polymorphisms, Julie A. Blanchong, Dennis M. Heisey, Kim T. Scribner, Scot V. Libants, Chad Johnson, Judd M. Aiken, Julia A. Langenberg, Michael D. Samuel

Julie A. Blanchong

The genetic basis of susceptibility to chronic wasting disease (CWD) in free-ranging cervids is of great interest. Association studies of disease susceptibility in free-ranging populations, however, face considerable challenges including: the need for large sample sizes when disease is rare, animals of unknown pedigree create a risk of spurious results due to population admixture, and the inability to control disease exposure or dose. We used an innovative matched case–control design and conditional logistic regression to evaluate associations between polymorphisms of complement C1q and prion protein (Prnp) genes and CWD infection in white-tailed deer from the CWD endemic area in ...


Reduction Of Water Surface Tension Significantly Impacts Gecko Adhesion Underwater, Peter Niewiarowski, Ali Dhinojwala, Alyssa Stark, Brandon Mcclung Mar 2015

Reduction Of Water Surface Tension Significantly Impacts Gecko Adhesion Underwater, Peter Niewiarowski, Ali Dhinojwala, Alyssa Stark, Brandon Mcclung

Dr. Peter H. Niewiarowski

The gecko adhesive system is dependent on weak van der Waals interactions that are multiplied across thousands of fine hair-like structures (setae) on geckos' toe pads. Due to the requirements of van der Waals forces, we expect that any interruption between the setae and substrate, such as a water layer, will compromise adhesion. Our recent results suggest, however, that the air layer (plastron) surrounding the superhydrophobic toe pads aid in expelling water at the contact interface and create strong shear adhesion in water when in contact with hydrophobic surfaces. To test the function of the air plastron, we reduced the ...


The Larvae Of Eurycea Junaluska (Amphibia: Caudata: Plethodontidae), With Comments On Distribution, Travis Ryan Feb 2015

The Larvae Of Eurycea Junaluska (Amphibia: Caudata: Plethodontidae), With Comments On Distribution, Travis Ryan

Travis J. Ryan

Travis J. Ryan's shorter contribution to Copeia 1997.


The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne Feb 2015

The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne

Travis J. Ryan

Reptile species are declining on a global scale. Six significant threats to reptile populations are habitat loss and degradation, introduced invasive species, environmental pollution, disease, unsustainable use, and global climate change.


Ultrastructure Of The Reproductive System Of The Black Swamp Snake (Seminatrix Pygaea): Part Ii. Annual Oviducal Cycle, David Sever, Travis Ryan, Deborah Patton, Shannon Swafford Feb 2015

Ultrastructure Of The Reproductive System Of The Black Swamp Snake (Seminatrix Pygaea): Part Ii. Annual Oviducal Cycle, David Sever, Travis Ryan, Deborah Patton, Shannon Swafford

Travis J. Ryan

This article is the first ultrastructural study on the annual oviducal cycle in a snake. The ultrastructure of the oviduct was studied in 21 females of the viviparous natricine snake Seminatrix pygaea. Specimens were collected and sacrificed in March, May, June, July, and October from one locale in South Carolina during 1998–1999. The sample included individuals: 1) in an inactive reproductive condition, 2) mated but prior to ovulation, and 3) from early and late periods of gravidity. The oviduct possesses four distinct regions from cranial to caudal: the anterior infundibulum, the posterior infundibulum containing sperm storage tubules (SSTs), the ...


Does Sex Influence Post-Reproductive Metamorphosis In Ambystoma Talpoideum?, Travis Ryan, Gabrielle Swenson Feb 2015

Does Sex Influence Post-Reproductive Metamorphosis In Ambystoma Talpoideum?, Travis Ryan, Gabrielle Swenson

Travis J. Ryan

Shorter communication in the Journal of Herpetology v. 35.


Eurycea Junaluska. Morphology, Travis Ryan Feb 2015

Eurycea Junaluska. Morphology, Travis Ryan

Travis J. Ryan

Morphology of Junaluska salamander.


Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis Ryan, Raymond Semlitsch Feb 2015

Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis Ryan, Raymond Semlitsch

Travis J. Ryan

Complex life cycles (CLCs) contain larval and adult phases that are morphologically and ecologically distinct. Simple life cycles (SLCs) have evolved from CLCs repeatedly in a wide variety of lineages but the processes that may underlie the transition have rarely been identified or investigated experimentally. We examined the influence of larval growth rate on the facultative expression of alternative life cycles (metamorphosis or maturation as gill-bearing adults [= paedomorphosis]) in the salamander Ambystoma talpoideum. We manipulated growth rates by altering the amount of food individuals received throughout larval development. The expression of alternative life cycles in A. talpoideum is influenced by ...


Evaporative Water Loss In Two Natricine Snakes, Nerodia Fasciata And Seminatrix Pygaea, Christopher Winne, Travis Ryan, Yale Leiden, Michael Dorcas Feb 2015

Evaporative Water Loss In Two Natricine Snakes, Nerodia Fasciata And Seminatrix Pygaea, Christopher Winne, Travis Ryan, Yale Leiden, Michael Dorcas

Travis J. Ryan

Shorter communication in Journal of Herpetology v. 35.


Aspects Of Sex-Specific Differences In The Expression Of An Alternative Life Cycle In The Salamander Ambystoma Talpoideum, Christopher Winne, Travis Ryan Feb 2015

Aspects Of Sex-Specific Differences In The Expression Of An Alternative Life Cycle In The Salamander Ambystoma Talpoideum, Christopher Winne, Travis Ryan

Travis J. Ryan

A recent evolutionary ecological model of facultative paedomorphosis predicts that body size of mature individuals should be larger than immatures of the same cohort. We investigated sex-specific differences in body size and maturation within a single cohort of branchiate (= larval and paedomorphic) mole salamanders, Ambystoma talpoideum. In addition, we also sampled the population after the breeding season, as some individuals began to undergo metamorphosis and leave the pond. The branchiate population was female-biased (62.7%), and mature (paedomorphic) females were significantly smaller than paedomorphic males or immature (larval) females. The majority of male branchiates were mature (86.6%), whereas significantly ...


Effects Of Hydroperiod On Metamorphosis In Rana Sphenocephala, Travis J. Ryan, Christopher T. Winne Feb 2015

Effects Of Hydroperiod On Metamorphosis In Rana Sphenocephala, Travis J. Ryan, Christopher T. Winne

Travis J. Ryan

Hydroperiod, the time a temporary pond holds water, is an important factor influencing recruitment in amphibian populations and structuring amphibian communities. We conducted an experiment to test the effect of hydroperiod on metamorphic traits of the southern leopard frog (Rana sphenocephala), a common amphibian in the southeastern United States. We reared larval R. sphenocephala in artificial ponds at a density of 32 larvae per tank (initial volume = approximately 650 liter). We dried the tanks according to natural patterns, using three different hydroperiods (60, 75 and 90 d). Experimental hydroperiods had a significant effect on the number of metamorphs and the ...


Life History Evolution And Adaptive Radiation Of Hemidactyliine Salamanders, Travis Ryan, R. Bruce Feb 2015

Life History Evolution And Adaptive Radiation Of Hemidactyliine Salamanders, Travis Ryan, R. Bruce

Travis J. Ryan

T.J. Ryan and R.C. Bruce's contribution to: The Biology of Plethodontid Salamanders, R. C. Bruce, R. G. Jaeger, and L. D. Houck, eds. Kluwer Academic/Plenum Publishers, New York.


Ultrastructure Of The Reproductive System Of The Black Swamp Snake (Seminatrix Pygaea). I. Evidence For Oviducal Sperm Storage, David Sever, Travis Ryan Feb 2015

Ultrastructure Of The Reproductive System Of The Black Swamp Snake (Seminatrix Pygaea). I. Evidence For Oviducal Sperm Storage, David Sever, Travis Ryan

Travis J. Ryan

Oviducal sperm storage in the viviparous (lecithotrophic) colubrid snake Seminatrix pygaea was studied by light and electron microscopy. Out of 17 adult snakes examined from May–October, sperm were found in the oviducts of only two specimens. In a preovulatory female sacrificed 14 May, sperm were found in the oviducal lumen and sperm storage tubules (SSTs) of the posterior infundibulum. In a nonvitellogenic female sacrificed 9 June, sperm were found in the lumen and glands of the posterior uterus and anterior vagina, indicating a recent mating. The glands in the posterior infundibulum and vagina were simple or compound tubular, whereas ...


Hatching Asynchrony, Survival, And The Fitness Of Alternative Adult Morphs In Ambystoma Talpoideum, Travis J. Ryan Feb 2015

Hatching Asynchrony, Survival, And The Fitness Of Alternative Adult Morphs In Ambystoma Talpoideum, Travis J. Ryan

Travis J. Ryan

The mole salamander, Ambystoma talpoideum, exhibits both aquatic (gilled) and terrestrial (metamorphosed) adult morphologies. Previous studies have shown the existence of body-size advantages associated with the terrestrial morph in A. talpoideum and other polymorphic salamanders (e.g., A. tigrinum). However, aquatic adult A. talpoideum mature at a younger age and often breed earlier than terrestrial adults. We tested the hypothesis that early maturation and reproduction in aquatic adults increase fitness (irrespective of body size). We reared larval A. talpoideum in mesocosms and varied the timing of hatching, with early-hatching larvae representing the offspring from early-breeding aquatic adults, and late-hatching larvae ...


Intraspecific Heterochrony And Life History Evolution: Decoupling Somatic And Sexual Development In A Facultatively Paedomorphic Salamander, Travis J. Ryan, Raymond D. Semlitsch Feb 2015

Intraspecific Heterochrony And Life History Evolution: Decoupling Somatic And Sexual Development In A Facultatively Paedomorphic Salamander, Travis J. Ryan, Raymond D. Semlitsch

Travis J. Ryan

Morphological features such as size and shape are the most common focus in studies of heterochronic change. Frequently, these easily observed and measured features are treated as a major target of selection, potentially ignoring traits more closely related to fitness. We question the primacy of morphological data in studies of heterochrony, and instead suggest that principal sources of fitness, such as life history characteristics, are not only the chief targets of selection, but changes in them may necessitate changes in other (subordinate) elements of the organism. We use an experimental approach to investigate the timing of metamorphosis and maturation in ...


Larval Life History And Abundance Of A Rare Salamander, Eurycea Junaluska (Plethodontidae), Travis Ryan Feb 2015

Larval Life History And Abundance Of A Rare Salamander, Eurycea Junaluska (Plethodontidae), Travis Ryan

Travis J. Ryan

The larval life history of Eurycea junaluska was studied in three southwestern North Carolina populations. Populations were sampled quarterly over a 13 mo period and size-class analyses were used to evaluate the pattern of larval growth and metamorphosis. Young of the year appeared in the late spring and experienced rapid growth through the first summer. Growth slowed in the second year and metamorphosis usually occured in the summer at about 25.5 mo post-hatching, although some data suggest that either 1yr or 3yr larval periods may be possible. The overall larval growth rate of E. junaluska is estimated at 1 ...


Biomass Turnover, Energy Balance, And Interpopulation Variation In The Stream Limpet, Ferrissia Rivularis (Say), With Special Reference To Respiration, Growth, And Fecundity, Albert Burky Feb 2015

Biomass Turnover, Energy Balance, And Interpopulation Variation In The Stream Limpet, Ferrissia Rivularis (Say), With Special Reference To Respiration, Growth, And Fecundity, Albert Burky

Albert J. Burky

This investigation extends from 1965 through 1968 and involves 42,926 individual measurements on 19,479 limpets from populations of F. rivularis in the Canandaigua Outlet at Alloway, New York (AL)* and in Black Creek at Cleveland, New York (BC)*, with some comparative results from a population in Chittenango Creek at Cazenovia, New York (CC)*. These localities are located in the Seneca-Clyde-Oneida drainage system which flows by way of the Oswego River into Lake Ontario. For populations at AL (eutrophic environment) and BC (mesotrophic environment) variations in life-cycle, accompanied by marked differences in fecundity and biomass turnover rates (growth and ...


Human-Wildlife Conflict-Causes, Consequences And Mitigation Measures With Special Reference To Kashmir, Aadil Habib, Ishfaq Nazir, Mustahson F. Fazili, Bilal A. Bhat Feb 2015

Human-Wildlife Conflict-Causes, Consequences And Mitigation Measures With Special Reference To Kashmir, Aadil Habib, Ishfaq Nazir, Mustahson F. Fazili, Bilal A. Bhat

JOZS JOURNAL

The rising levels of man-animal conflicts at various locations of Kashmir valley in India are due to close proximity between humans and wild carnivores particularly leopard and black bear. The data regarding human injuries and mortalities caused during conflicts from 2010 to 2012 was collected from Shere Kashmir Institute of Medical Sciences (SKIMS) Soura, Srinagar and its associated medical college hospital at Bemina Srinagar. The data indicates rising levels of man-carnivore conflicts in Kashmir. The leopard and Asiatic black bear were mainly involved in causing several forms of conflict. The human population growth and expansion, habitat degradation and fragmentation, land ...