Life Sciences Commons^™

A Road Out Of Naknek Part One: The Tide Turns, Keith Wilson

All NMU Master's Theses

I make an annual summertime return to Naknek, a town on Bristol Bay where the salmon have made their own annual summertime return for thousands of years. My thesis is a series of nonfiction essays about my background there, both as a commercial fisherman and my upbringing. It is something I consider the “Part One” of a book still under the process of writing. It is a series of essays, alternating these two motifs of the salmon and of my experiences growing up somewhere like Naknek.

I constructed this thesis to read like the tide. Bristol Bay salmon go out …

Fleas Of The American Pika: Diversity And Biogeography In North America’S Intermountain West, Niyomi Wijewardena

All NMU Master's Theses

American pikas (Ochotona princeps) are small mammals that are widely distributed across North America’s Intermountain West. Previous investigations revealed five geographically distinct mitochondrial lineages within O. princeps associated with different mountain systems of the Intermountain West. In contrast, diversity of endoparasitic helminths of pikas is not structured geographically in the same way. Instead, there are two primary parasite assemblages, one distributed across southwestern pika populations and one found across the northeastern part of the host range. These contrasting patterns suggest that the shared history of pikas and their parasites had different consequences for the evolutionary trajectories of these …

Phylogenetic Studies Of The Madagascan Freshwater Crabs (Potamoidea, Potamonautidae, Deckeniinae), Rainee Stevens

All NMU Master's Theses

Relationships within the Madagascan freshwater crab fauna were examined based on unstudied specimens from all parts of Madagascar. This study allowed the examination of the validity of existing genera and species, and identified potential new taxa. The new specimens provided phylogenetic and evolutionary data, as well as new insights into the distribution patterns of the Malagasy freshwater crab fauna. In addition, the large number of new localities from previously unsurveyed areas of Madagascar allowed the construction of updated distribution maps.

The present analysis included 62 unidentified specimens plus 13 identified species of Malagasy freshwater crab taxa that had already been …

Comparative Biogeography Of North American Pika Parasites: Unraveling A History Driven By Climate Change, Heather M. Toman

All NMU Master's Theses

Parasites are an understudied group that can provide important information on ecosystem dynamics and climate change as well as host biogeographic history. I performed a comparative biogeographic study on two endoparasitic helminth lineages associated with pikas (Ochotona) -the tapeworm genus Schizorchis and the pinworm subgenus Labiostomum (Eugenuris). Colonization history across Beringia was assessed using analyses of historical range estimation and tests for simultaneous divergence. Analysis results allow me reject the hypothesis that these parasites colonized the Nearctic during a single glacial cycle, as evidenced by multiple Nearctic and Palearctic lineage pairs that did not diverge simultaneously. This …