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Full-Text Articles in Life Sciences

Population Ecology Of The Golden Mouse, Robert K. Rose Jan 2008

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 …


Oviposition Behavior Partitions Aquatic Landscapes Along Predation And Nutrient Gradients, C. A. Binckley, W. J. Resetarits Jr. Jan 2008

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 Jan 2008

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 …


Accelerated Exchange Of Exon Segments In Viperid Three-Finger Toxin Genes (Sistrurus Catenatus Edwardsii; Desert Massasauga), Robin Doley, Susanta Pahari, Stephen P. Mackessy, Manjunatha Kini Jan 2008

Accelerated Exchange Of Exon Segments In Viperid Three-Finger Toxin Genes (Sistrurus Catenatus Edwardsii; Desert Massasauga), Robin Doley, Susanta Pahari, Stephen P. Mackessy, Manjunatha Kini

Biological Sciences Faculty Publications

BACKGROUND: Snake venoms consist primarily of proteins and peptides showing a myriad of potent biological activities which have been shaped by both adaptive and neutral selective forces. Venom proteins are encoded by multigene families that have evolved through a process of gene duplication followed by accelerated evolution in the protein coding region. RESULTS: Here we report five gene structures of three-finger toxins from a viperid snake, Sistrurus catenatus edwardsii. These toxin genes are structured similarly to elapid and hydrophiid three-finger toxin genes, with two introns and three exons. Both introns and exons show distinct patterns of segmentation, and the insertion/deletion …


Genomic Organization And Phylogenetic Utility Of Deer Mouse (Peromyscus Maniculatus) Lymphotoxin-Alpha And Lymphotoxin-Beta, Tiffany Richens, Aparna D.N. Palmer, Joseph Prescott, Tony Schountz Jan 2008

Genomic Organization And Phylogenetic Utility Of Deer Mouse (Peromyscus Maniculatus) Lymphotoxin-Alpha And Lymphotoxin-Beta, Tiffany Richens, Aparna D.N. Palmer, Joseph Prescott, Tony Schountz

Biological Sciences Faculty Publications

BACKGROUND: Deer mice (Peromyscus maniculatus) are among the most common mammals in North America and are important reservoirs of several human pathogens, including Sin Nombre hantavirus (SNV). SNV can establish a life-long apathogenic infection in deer mice, which can shed virus in excrement for transmission to humans. Patients that die from hantavirus cardiopulmonary syndrome (HCPS) have been found to express several proinflammatory cytokines, including lymphotoxin (LT), in the lungs. It is thought that these cytokines contribute to the pathogenesis of HCPS. LT is not expressed by virus-specific CD4+ T cells from infected deer mice, suggesting a limited role for this …


Scientific Review For The Identification Of Critical Habitat For Woodland Caribou (Rangifer Tarandus Caribou), Boreal Population, In Canada, Mark Hebblewhite, Environment Canada Jan 2008

Scientific Review For The Identification Of Critical Habitat For Woodland Caribou (Rangifer Tarandus Caribou), Boreal Population, In Canada, Mark Hebblewhite, Environment Canada

Biological Sciences Faculty Publications

Woodland Caribou (Rangifer tarandus caribou), Boreal Population (herein referred to as boreal caribou), are formally listed as Threatened under the federal Species at Risk Act (SARA). The Act requires the Minister of Environment to prepare a Recovery Strategy for the species that includes, to the extent possible and based upon the best available information, an identifi cation of its Critical Habitat and/or, if there is insuffi cient information available, a Schedule of Studies to determine that information. In August 2007, Environment Canada (EC) launched a science-based review with the mandate to identify Critical Habitat to the extent possible, using the …


What Constitutes A Natural Fire Regime? Insight From The Ecology And Distribution Of Coniferous Forest Birds In North America, Richard L. Hutto, Courtney J. Conway, Victoria A. Saab, Jeffrey R. Walters Jan 2008

What Constitutes A Natural Fire Regime? Insight From The Ecology And Distribution Of Coniferous Forest Birds In North America, Richard L. Hutto, Courtney J. Conway, Victoria A. Saab, Jeffrey R. Walters

Biological Sciences Faculty Publications

Bird species that specialize in the use of burned forest conditions can provide insight into the prehistoric fire regimes associated with the forest types that they have occupied over evolutionary time. The nature of their adaptations reflects the specific post-fire conditions that occurred prior to the unnatural influence of humans after European settlement. Specifically, the post-fire conditions, nest site locations, and social systems of two species (Bachman's sparrow [Aimophila aestivalis] and red-cockaded woodpecker [Picoides borealis]) suggest that, prehistorically, a frequent, low-severity fire regime characterized the southeastern pine system in which they evolved. In contrast, the patterns …


Competitive Abilities Of Native Grasses And Non-Native (Bothriochloa Spp.) Grasses, Cheryl D. Schmidt, Rob Channell Ph.D., Karen R. Hickman, Keith Harmoney, William J. Stark Ph.D. Jan 2008

Competitive Abilities Of Native Grasses And Non-Native (Bothriochloa Spp.) Grasses, Cheryl D. Schmidt, Rob Channell Ph.D., Karen R. Hickman, Keith Harmoney, William J. Stark Ph.D.

Biological Sciences Faculty Publications

Old World Bluestems (OWB), introduced from Europe and Asia in the 1920s, recently have begun to raise concerns in the Great Plains. Despite suggestion in the late 1950s that OWB were weedy and negatively impacted biological diversity, they were widely introduced throughout the Great Plains for agricultural purposes. Anecdotal evidence suggests that OWB exhibit invasive characteristics that promote competitive exclusion of native species. The objective of our study was to quantify the competitive abilities of two OWB species (Caucasian bluestem; Bothriochloa bladhii (Retz.) S. T. Blake (= Bothriochloa caucasica (Trin.) C. E. Hubb.) and yellow bluestem; Bothriochloa ischaemum (L.) Keng) …