Open Access. Powered by Scholars. Published by Universities.®

Comparative and Evolutionary Physiology Commons™

Open Access. Powered by Scholars. Published by Universities.®

University of Nebraska - Lincoln

Discipline
Keyword
Publication Year
Publication

Articles 1 - 6 of 6

Full-Text Articles in Comparative and Evolutionary Physiology

Patterns Of Morphological And Molecular Evolution In The Antillean Tree Bat, Ardops Nichollsi (Chiroptera: Phyllostomidae), Roxanne J. Larsen, Peter A. Larsen, Caleb D. Phillips, Hugh H. Genoways, Gary G. Kwiecinski, Scott C. Pedersen, Carleton J. Phillips, Robert J. Baker Mar 2017

Patterns Of Morphological And Molecular Evolution In The Antillean Tree Bat, Ardops Nichollsi (Chiroptera: Phyllostomidae), Roxanne J. Larsen, Peter A. Larsen, Caleb D. Phillips, Hugh H. Genoways, Gary G. Kwiecinski, Scott C. Pedersen, Carleton J. Phillips, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

Species endemic to oceanic islands offer unique insights into the mechanisms underlying evolution and have served as model systems for decades. Often these species show phenotypic variation that is correlated with the ecosystems in which they occur and such correlations may be a product of genetic drift, natural selection, and/or environmental factors. We explore the morphologic and genetic variation within Ardops nichollsi, a species of phyllostomid bat endemic to the Lesser Antillean islands. Ardops nichollsi is an ideal taxon to investigate the tempo of evolution in Chiroptera, as it: is a recently derived genus in the family Phyllostomidae; contains …


Factors Affecting The Immune System Of The Ornate Box Turtle (Errapene Ornata), Michelle W. Mcquinn, Abigail A. Neyer, Gwendolyn C. Bachman Apr 2016

Factors Affecting The Immune System Of The Ornate Box Turtle (Errapene Ornata), Michelle W. Mcquinn, Abigail A. Neyer, Gwendolyn C. Bachman

UCARE: Research Products

While many studies have detailed the complex intricacies of the endothermic immune system, relatively little is known about the immune system of ectotherms--specifically, reptiles. In an attempt to gain more knowledge about the factors affecting reptilian immune function, ornate box turtles (Terrapene ornata) were subjected to chronic stress in the form of high ambient temperatures in a semi-natural environment. It was hypothesized that chronic stress would lead to elevated levels of corticosterone in the blood, which would, in turn, suppress immune activity. It was found that body temperature and body mass in particular were significantly affected by chronic heat stress. …


Evolution Of Starvation Resistance In Drosophila Melanogaster: Measurement Of Direct And Correlated Responses To Artificial Selection, Tiffany E. Schwasinger-Schmidt, Stephen D. Kachman, Lawrence G. Harshman Jan 2012

Evolution Of Starvation Resistance In Drosophila Melanogaster: Measurement Of Direct And Correlated Responses To Artificial Selection, Tiffany E. Schwasinger-Schmidt, Stephen D. Kachman, Lawrence G. Harshman

Lawrence G. Harshman Publications

Laboratory selection for resistance to starvation has been conducted under relatively controlled conditions to investigate direct and correlated responses to artificial selection. With regard to starvation resistance, there are three physiological routes by which the trait can evolve: resource accumulation, energy conservation and starvation tolerance. A majority of energetic compounds and macromolecules including triglycerides, trehalose and other sugars, and soluble protein increased in abundance as a result of selection. Movement was additionally investigated with selected males moving less than control males and selected females exhibiting a similar response to selection. Results obtained from this study supported two of the possible …


Mice Deficient In The Serine/Threonine Protein Kinase Vrk1 Are Infertile Due To A Progressive Loss Of Spermatogonia, Matthew S. Wiebe, R. Jeremy Nichols, Tyler P. Molitor, Jill K. Lindgren, Paula Traktman Jan 2009

Mice Deficient In The Serine/Threonine Protein Kinase Vrk1 Are Infertile Due To A Progressive Loss Of Spermatogonia, Matthew S. Wiebe, R. Jeremy Nichols, Tyler P. Molitor, Jill K. Lindgren, Paula Traktman

Nebraska Center for Virology: Faculty Publications

The VRK1 protein kinase has been implicated as a proproliferative factor. Genetic analyses of mutant alleles of the Drosophila and Caenorhabditis elegans VRK1 homologs have revealed phenotypes ranging from embryonic lethality to mitotic and meiotic defects with resultant sterility. Herein, we describe the first genetic analysis of murine VRK1. Two lines of mice containing distinct gene-trap integrations into the Vrk1 locus were established. Insertion into intron 12 (GT12) spared VRK1 function, enabling the examination of VRK1 expression in situ. Insertion into intron 3 (GT3) disrupted VRK1 function, but incomplete splicing to the gene trap rendered this allele hypomorphic (~15% of …


Morphological Variation In The Southeastern Pocket Gopher, Geomys Pinetis (Mammalia: Rodentia), Stephen L. Williams, Hugh H. Genoways Dec 1980

Morphological Variation In The Southeastern Pocket Gopher, Geomys Pinetis (Mammalia: Rodentia), Stephen L. Williams, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

The nominal species of southeastern pocket gophers (Geomys pinetis, G. colonus, G. cumberlandius, and G. fontanelus), which collectively occupy a geographic range on the Atlantic and Gulf coastal plain of Alabama, Georgia, and Florida, were examined for morphological variation. Univariate and multivariate analyses were used to determine age, sexual, individual, and geographic variation in G. pinetis. Significant differences were found among different age classes and between sexes. Males displayed higher individual variation than females and external measurements were more variable than cranial measurements. Of the four named species in the pinetis-species group (colonus …


Critical Flicker Frequency In A Harp Seal, Pagophilus Groenlandicus (Erxleben, 1777), Charles D. Bernholz Jan 1973

Critical Flicker Frequency In A Harp Seal, Pagophilus Groenlandicus (Erxleben, 1777), Charles D. Bernholz

University of Nebraska-Lincoln Libraries: Faculty Publications

Critical flicker frequency (CFF) in a free-swimming harp seal (Pagophilus groenlandicus) was investigated using behavioral techniques. The resulting CFF versus intensity contour indicates a definite rod-cone break, confirming a duplex photoreceptor population whose presence had not been observed in previous morphological reports.