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Full-Text Articles in Life Sciences
Beringian Biogeography: Patterns Of Intercontinental Dispersal And The Structuring Of A Holarctic Tapeworm Genus, Genevieve M. Haas
Beringian Biogeography: Patterns Of Intercontinental Dispersal And The Structuring Of A Holarctic Tapeworm Genus, Genevieve M. Haas
All NMU Master's Theses
The opening and closing of the Bering Land Bridge due to Pleistocene climate fluctuations facilitated the exchange of taxa between the Palearctic and Nearctic. While many studies have worked toward elucidating the role of Beringia in assembling northern faunas, relatively little work has focused on parasites. Here I examine the number and direction of transberingian colonization events within the Holarctic tapeworm genus, Arostrilepis Mas-Coma & Tenora, 1997. I performed maximum likelihood and multi-locus coalescent phylogenetic reconstructions using mitochondrial and nuclear DNA sequences. Biogeographic ancestral range estimations were conducted on the resulting species phylogeny. My systematic reconstructions reveal as many as …
Fleas Of The American Pika: Diversity And Biogeography In North America’S Intermountain West, Niyomi Wijewardena
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 …
Comparative Biogeography Of North American Pika Parasites: Unraveling A History Driven By Climate Change, Heather M. Toman
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 …