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Full-Text Articles in Life Sciences

Body Size And Growth Patterns Of Microtus Pennsylvanicus (Ord.) In Chesapeake, Virginia, Sara E. Bell Apr 2010

Body Size And Growth Patterns Of Microtus Pennsylvanicus (Ord.) In Chesapeake, Virginia, Sara E. Bell

Biological Sciences Theses & Dissertations

From Dec 2002-Feb 2008, a capture-mark-release study was conducted on 2 Chesapeake, Virginia populations of meadow voles (Microtus pennsylvanicus). The study sites were effectively 1 ha grids in old fields. Two modified live Fitch-type traps were placed at 12.5 m intervals on grids that were trapped for 3 days each month. In northern North America, voles have distinct breeding cohorts (spring and autumn), experience autumn and winter weight loss, demonstrate both delayed growth and sexual maturation in autumn-born young, have lifespans less than 15 weeks, and average about 35-50 g as adults. Chesapeake voles bred year-round, experienced no …


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 Jan 2010

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 Jan 2010

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 …