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Showing 1 to 12 of 12 for “"pika"”.
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Molecular evolutionary analysis of the American pika (Ochotona princeps)
<p>American pika (<em>Ochotona princeps</em>) are small winter-active mammals inhabiting alpine environments. As the American pika occupies a niche characterized by hypoxia, these animals are an excellent system to use for detecting genetic changes associated with adaptation to these conditions. …
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FLEAS OF THE AMERICAN PIKA: DIVERSITY AND BIOGEOGRAPHY IN NORTH AMERICA’S INTERMOUNTAIN WEST
<p>American pikas (<em>Ochotona princeps</em>) are small mammals that are widely distributed across North America’s Intermountain West. Previous investigations revealed five geographically distinct mitochondrial lineages within <em>O. princeps </em>associated with different mountain systems of the …
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COMPARATIVE BIOGEOGRAPHY OF NORTH AMERICAN PIKA PARASITES: UNRAVELING A HISTORY DRIVEN BY CLIMATE CHANGE
… endoparasitic helminth lineages associated with pikas (<em>Ochotona</em>) -the tapeworm genus <em>Schizorchis</em> and the pinworm subgenus <em>Labiostomum (Eugenuris)</em>. Colonization history across Beringia was assessed using analyses of historical range estimation and tests for simultaneous …
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The Hitchhiker's Guide to the Host: Fleas and the History of Pikas in North America
… not recorded by the phylogenetics of the host. Pikas (small lagomorphs) host a diverse parasite community comprising endoparasites (e.g., coccidians, nematodes, and cestodes) and ectoparasites (e.g., fleas and mites). Phylogenetic analysis of pika endoparasites has revealed pikas evolved in Asia …
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Middle Cambrian linguliformean brachiopods of the Pika and Sullivan formations, southern Canadian Rocky Mountains, Alberta, Canada
… collected and described from the middle Cambrian Pika and Sullivan formations in the southern Canadian Rocky Mountains. These formations consist of coarse-grained grainstone interbedded with lime mudstones and siltstones in a storm-influenced, distal offshore setting. Grainstone and rudstone beds …
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Understanding the complex relationships between climate, vegetation, and foraging behavior of a climate-sensitive alpine mammal in order to explain patterns of persistence
… highly sensitive to climate change. The American pika (<em>Ochotona princeps</em>) serves as an indicator species of climate change and a model organism for studying its impacts on mountain mammals. Certain aspects of plant community composition and structure can function as predictors of pika …
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Integrating multiple sign types to improve occupancy estimation for inconspicuous species: a case study of American pika in the Pacific Northwest
… for inconspicuous species like the American pika (Ochotona princeps). In this study, we modeled occupancy dynamics for American pika using multiple direct and indirect indicators of pika presence (fresh scat, fresh haypiles, pika calls and pika sightings) collected from 2010 to 2021 at five …
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Testing the forage preference of the American pika (Ochotona princeps) for use in connectivity corridors in the Washington Cascades
… a 15-mile stretch of Interstate-90. American pikas (<em>Ochotona princeps</em>) are being monitored for the SPEP because they have specific habitat requirements and are poor dispersers. Making the crossing structures “pika-friendly” will encourage these low-mobility animals to use the …
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Influence Of Landscape On Gene Differentiation In The American Pika (Ochotona princeps) Within The Interstate 90 Snoqualmie Pass Corridor
… compare genetic connectivity among 13 American pika (<em>Ochotona princeps</em>) habitat patches across an approximately 77 square km area adjacent to Interstate 90 near Snoqualmie Pass, WA. Tissue samples were collected from 85 individuals and genotyped at six microsatellite loci to determine …
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Molecular Evolution in the Mountains: Genetic Affinity and the Environment led to Adaptive Variation in the American Pika (Ochotona princeps)
<p>The American pika (<em>Ochotona princeps</em>) is discontinuously distributed in high elevation and montane regions across western North America, where isolated lineages have potentially evolved along divergent trajectories since the mid-Pleistocene. <em>Ochotona princeps</em> encounters cold …
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Are Highways Stressful for Pikas?: Analysis of Stress Hormones of the American Pika (<i>Ochotona princeps</i>) Living Adjacent to Interstate 90 in the Cascade Range of Washington State
… in a low-mobility species, the American Pika (<em>Ochotona princeps</em>), living in anthropogenic rock embankment along Interstate 90 (highway) in the Cascade Range of Washington. I extracted fecal glucocorticoid metabolite (fGCM) concentrations from fresh fecal samples to determine …
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New cytotoxic natural products from North-Eastern Pacific marine invertebrates
An investigation into the chemistry of four species of marine invertebrates which were found to produce cytotoxic crude extracts (ED50 against the L1210 murine leukemia cell line 5 30 pg/mL) led to the isolation of nine new and eleven previously known secondary metabolites. The structures of the …