Zoology Commons^™

A Study Of Defensive Mechanisms Employed By Two Species Of Nudibranchs Using Toxicity And Unpalatability Analyses, Sean Youn

Independent Study Project (ISP) Collection

Nudibranchs are marine invertebrates that have developed an intriguing defense mechanism, including warning coloration and the use of chemicals accumulated through their sponge diet. The goal of this study was to determine whether the strength of chemical defenses differs between dietary and accumulated secondary metabolites for two species: Glossodoris vespa and Ceratosoma brevicaudatum. First, NMR spectroscopy was used to not only identify specific compounds in the mantle (outer covering) and the viscera (gut) but also to analyze the possibility of nudibranch species transporting more toxic compounds for defensive purposes. Next, toxicity (brine shrimp) and palatability (Palaemon shrimp) assays were used …

Rare, Threatened And Endangered Species Of Oregon (2016), James S. Kagan, Sue Vrilakas, John A. Christy, Eleanor P. Gaines, Lindsey Wise, Cameron Pahl, Kathy Howell

Institute for Natural Resources Publications

Extinction is a natural process. Today, however, plant and animal species are disappearing world-wide at an accelerated pace. Based on current trends, half of the species on earth will be extinct within the next 100 years. The major reasons for this are human caused changes to the environment, which continue to increase - in Oregon and throughout the world.

Once lost, a species can never be recovered, and there is no way of knowing how useful it may have been. We do know that human beings and many of their industries depend on plant and animal products. About 50% of …

Walking Behavior Of Zoo Elephants: Associations Between Gps-Measured Daily Walking Distances And Environmental Factors, Social Factors, And Welfare Indicators, Matthew Robert Holdgate, Cheryl L. Meehan, Jennifer N. Hogan, Lance J. Miller, Josesph Soltis, Jeff Andrews, David J. Shepherdson

Biology Faculty Publications and Presentations

Research with humans and other animals suggests that walking benefits physical health. Perhaps because these links have been demonstrated in other species, it has been suggested that walking is important to elephant welfare, and that zoo elephant exhibits should be designed to allow for more walking. Our study is the first to address this suggestion empirically by measuring the mean daily walking distance of elephants in North American zoos, determining the factors that are associated with variations in walking distance, and testing for associations between walking and welfare indicators. We used anklets equipped with GPS data loggers to measure outdoor …

Recumbence Behavior In Zoo Elephants: Determination Of Patterns And Frequency Of Recumbent Rest And Associated Environmental And Social Factors, Matthew Robert Holdgate, Cheryl L. Meehan, Jennifer N. Hogan, Lance J. Miller, Jeff Rushen, Anne-Marie De Passillé, Josesph Soltis, Jeff Andrews, David J. Shepherdson

Biology Faculty Publications and Presentations

Resting behaviors are an essential component of animal welfare but have received little attention in zoological research. African savanna elephant (Loxodonta africana) and Asian elephant (Elephas maximus) rest includes recumbent postures, but no large-scale investigation of African and Asian zoo elephant recumbence has been previously conducted. We used anklets equipped with accelerometers to measure recumbence in 72 adult female African (n = 44) and Asian (n = 28)elephants housed in 40 North American zoos. We collected 344 days of data and determined associations between recumbence and social, housing, management, and demographic factors. African elephants were recumbent less (2.1 hours/day, S.D. …

Range-Wide Patterns Of Geographic Variation In Songs Of Golden-Crowned Sparrows (Zonotrichia Atricapilla), Daizaburo Shizuka, M Ross Lein, Glen Chilton

School of Biological Sciences: Faculty Publications

Discrete geographic variation, or dialects, in songs of songbirds arise as a consequence of complex interactions between ecology and song learning. Four of the five species of Zonotrichia sparrows, including the model species White-crowned Sparrow (Z. leucophrys), have been studied with respect to the causes and consequences of geographic variation in song. Within White-crowned Sparrows, subspecies that migrate farther have larger range size of dialects. Here, we assessed geographic patterns of song variation in the fifth species of this genus, the Golden-crowned Sparrow (Z. atricapilla). We analyzed field-recorded songs from 2 sampling periods (1996–1998 and 2006–2013) …

Elevational Variation In Body-Temperature Response To Immune Challenge In A Lizard, Francisco Javier Zamora-Camacho, Senda Reguera, Gregorio Moreno-Rueda

Dartmouth Scholarship

Immunocompetence benefits animal fitness by combating pathogens, but also entails some costs. One of its main components is fever, which in ectotherms involves two main types of costs: energy expenditure and predation risk. Whenever those costs of fever outweigh its benefits, ectotherms are expected not to develop fever, or even to show hypothermia, reducing costs of thermoregulation and diverting the energy saved to other components of the immune system. Environmental thermal quality, and therefore the thermoregulation cost/benefit balance, varies geographically. Hence, we hypothesize that, in alpine habitats, immune-challenged ectotherms should show no thermal response, given that (1) hypothermia would be …

Molecular Analysis Confirming The Introduction Of Nile Crocodiles, Crocodylus Niloticus Laurenti 1768 (Crocodylidae), In Southern Florida, With An Assessment Of Potential For Establishment, Spread, And Impacts., Michael R. Rochford, Kenneth L. Krysko, Frank J. Mazzotti, Matthew W. Shirley, Mark W. Parry, Joseph A. Wasilewski, Jeffrey S. Beauchamp, Christpher R. Gillette, Edward F. Metzger Iii, Michiko A. Squires, Louis A. Somma

Papers in Herpetology

The state of Florida, USA, has more introduced herpetofauna than any other governmental region on Earth. Four species of nonnative crocodilians have been introduced to Florida (all since 1960), one of which is established. Between 2000–2014 we field-collected three nonnative crocodilians in Miami-Dade County, Florida, and one in Hendry County, Florida. We used DNA barcoding and molecular phylogenetics to determine species identification and native range origin. Also, we described diet, movement, and growth for one crocodile. Our molecular analyses illustrated that two of the crocodiles we collected are most closely related to Nile Crocodiles (Crocodylus niloticus) from South Africa, suggesting …

Global Phylogeny Of The Water Penny Beetles Using Both Molecular And Morphological Evidence (Co, Mathew Vincent Wood

Masters Theses & Specialist Projects

The Psephenidae is a family of freshwater beetles usually found in swift streams worldwide. Their unique disc shaped and flattened larvae have made this a group of interest for scientists for centuries. Morphologically, this family has been relatively well researched, and systematically the family is fairly well known and supported as monophyletic. One issue with Psephenidae, and with many other insect groups, is the lack of the molecular phylogenetic analyses to test morphology hypothesizes.

After successfully sequencing these two genes from species representing nearly all of the known genera, the data were analyzed using both Bayesian and parsimony methods. Analyses …

Skeletal Muscle Mass And Composition During Mammalian Hibernation, Clark J. Cotton

Biology Faculty Publications

Hibernation is characterized by prolonged periods of inactivity with concomitantly low nutrient intake, conditions that would typically result in muscle atrophy combined with a loss of oxidative fibers. Yet, hibernators consistently emerge from winter with very little atrophy, frequently accompanied by a slight shift in fiber ratios to more oxidative fiber types. Preservation of muscle morphology is combined with down-regulation of glycolytic pathways and increased reliance on lipid metabolism instead. Furthermore, while rates of protein synthesis are reduced during hibernation, balance is maintained by correspondingly low rates of protein degradation. Proposed mechanisms include a number of signaling pathways and transcription …

New Verified Nonindigenous Amphibians And Reptiles In Florida Through 2015, With A Summary Of More Than 152 Years Of Introductions., Kenneth L. Krysko, Louis A. Somma, Dustin C. Smith, Christopher R. Gillette, Daniel Cueva, Joseph A. Wasilewski, Kevin M. Enge, Steve A. Johnson, Todd S. Campbell, Jake R. Edwards, Michael R. Rochford, Ryan Tompkins, Jeffrey L. Fobb, Scott Mullin, Christopher J. Lechowicz, Dallas Hazelton, Alície Warren

Papers in Herpetology

More nonindigenous species occur in Florida, USA, than any other region worldwide and may threaten many of Florida’s natural resources. The frequency of new reports mandates the need for regular updates. Herein, we use photographic and specimen vouchers in addition to literature records to provide updated information on verified nonindigenous amphibians and reptiles in Florida. Between our most recent summary in 2012 and the end of 2015, 38 additional species are known to have been intercepted (n = 2) or introduced (n = 36). We also update the invasion stage of seven species previously reported from Florida and report that …

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

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, …