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Full-Text Articles in Population Biology
Population Genetic Structure And Parasite Communities In A Nomadic Songbird, The Red Crossbill (Loxia Curvirostra), Erica L. Lovett
Population Genetic Structure And Parasite Communities In A Nomadic Songbird, The Red Crossbill (Loxia Curvirostra), Erica L. Lovett
Electronic Thesis and Dissertation Repository
Although much speciation occurs in allopatry, populations with overlapping geographic ranges may also experience reduced gene flow due to ecological differences. Parasites are an important feature of the biotic environment, and place important selective pressures on their hosts, potentially reducing gene flow among geographically separated host populations. However, virtually nothing is known about host-parasite interactions in systems where hosts have nomadic distributions, and where ecologically distinct populations exist in sympatry. I examined population genetic structuring and characterized bloodborne parasite communities across four ecologically distinct, but partially sympatric, “vocal types” of nomadic red crossbills (Loxia curvirostra) sampled at multiple …
Weather And Photoperiod Indices Of Autumn And Winter Dabbling Duck Abundance In The Mississippi And Atlantic Flyways Of North America, Lena M. Van Den Elsen
Weather And Photoperiod Indices Of Autumn And Winter Dabbling Duck Abundance In The Mississippi And Atlantic Flyways Of North America, Lena M. Van Den Elsen
Electronic Thesis and Dissertation Repository
Climate change may influence autumn and winter distributions of dabbling ducks throughout the Atlantic and Mississippi Flyways of North America. To determine how weather and photoperiod influenced autumn-winter abundances of dabbling ducks at staging areas in eastern North America, I modeled weather and photoperiod variables with rate of change in relative abundance of various dabbling duck species over space and time. Latitude was incorporated into models to determine if changes in duck abundance in relation to weather severity were influenced by locale. Changes in abundance were best described by weather models incorporating temperature and snowfall variables for all species except …