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Full-Text Articles in Animal Sciences
Biogeography Of The American Pika (Ochotona Princeps) In Oregon And Southern Washington: Illuminating Genetic Relationships Among Disjunct Populations, George Washington Batten Iii
Biogeography Of The American Pika (Ochotona Princeps) In Oregon And Southern Washington: Illuminating Genetic Relationships Among Disjunct Populations, George Washington Batten Iii
Dissertations and Theses
The American pika (Ochotona princeps) finds moderately warm temperatures (>25°C) lethally stressful, and at the end of the last Ice Age 10,000 years ago was forced to disperse to cooler, "sky island" mountaintops where they are almost exclusively found today. Thirty six subspecies are recognized, all established using morphological characters, and it is uncertain whether these subspecies' designations are corroborated by genetic analyses. This study elucidates three hypotheses regarding populations in Oregon and southern Washington: 1) O. p. fumosa constitutes a subspecies distinct form O. p. brunnescens, 2) the Columbia River constitutes a barrier to gene …
Spatial Segregation Of The Sexes In A Salt Marsh Grass Distichlis Spicata (Poaceae), Charlene Ashley Mercer
Spatial Segregation Of The Sexes In A Salt Marsh Grass Distichlis Spicata (Poaceae), Charlene Ashley Mercer
Dissertations and Theses
Understanding the maintenance of sexual systems is of great interest to evolutionary and ecological biologists because plant systems are extremely varied. Plant sexual systems have evolved to include not only complete plants with both male and female reproduction occurring on one plant (i.e., monoecious and hermaphroditic) but also plants with male and female function on separate plants (dioecious). The dioecious reproductive system can be used to test theories on niche differentiation given that having separate plants potentially allows for the exploitation of a broader niche. This increase in the realized niche is due to the ability for separate sexes to …