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Coyotes-Wolves-Cougars.blogspot.com

Grizzly bears, black bears, wolves, coyotes, cougars/ mountain lions,bobcats, wolverines, lynx, foxes, fishers and martens are the suite of carnivores that originally inhabited North America after the Pleistocene extinctions. This site invites research, commentary, point/counterpoint on that suite of native animals (predator and prey) that inhabited The Americas circa 1500-at the initial point of European exploration and subsequent colonization. Landscape ecology, journal accounts of explorers and frontiersmen, genetic evaluations of museum animals, peer reviewed 20th and 21st century research on various aspects of our "Wild America" as well as subjective commentary from expert and layman alike. All of the above being revealed and discussed with the underlying goal of one day seeing our Continent rewilded.....Where big enough swaths of open space exist with connective corridors to other large forest, meadow, mountain, valley, prairie, desert and chaparral wildlands.....Thereby enabling all of our historic fauna, including man, to live in a sustainable and healthy environment. - Blogger Rick

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Tuesday, December 18, 2018

"Coyotes (Canis latrans) provide a tractable system to address questions related to range expansion genomics"..............."Confined to the western and central regions of North America prior to 1900 (hereafter referred to as the coyote historical range), coyotes have substantially expanded their geographic range over the last century to occupy every continental US state and Canadian province"............."The research paper(click on link below to read full paper) focuses on the eastward expansion across the midwestern US and southeastern Canada, culminating along the eastern seaboard"..............."This expansion began in the early 20th century and followed two broad expansion routes across distinct environments"..........."In the northeast, coyotes expanded across the Great Lakes region of the United States and Canada into New England, New York, and Pennsylvania"..............."The southeastern expansion occurred at a slower rate and followed an approximate trajectory through Louisiana, Alabama, and Georgia, with initial reports of coyotes in the Carolinas as recently as the 1980s".............."Though fine‐scale variation in expansion routes has been documented for the northeast , a recent genetic survey supports two genetically distinct eastern coyote populations across the eastern seaboard that correspond to these broadly described northeastern and southeastern expansion routes, suggesting that fine‐scale expansion routes have likely converged".............."Counter to theoretical expectations for populations to bottleneck during range expansions, the research team observed minimal evidence for decreased genomic diversity across coyotes sampled along either expansion front, which is likely due to hybridization with other Canis species(e.g. eastern and red wolves, with a touch of domestic dog)".

READ FULL ARTICLE BY CLICKING ON LINK



ORIGINAL RESEARCH

 Range expansion is a widespread biological process, with well‐described theoretical expectations associated with the colonization of novel ranges. However, comparatively few empirical studies address the genomic outcomes accompanying the genome‐wide consequences associated with the range expansion process, particularly in recent or ongoing expansions.

Map of coyote historical range, 1950s range, 2000s range, and sample size per location. Ranges are approximate and modified from Hody and Kays (2018)














 Here, we assess two recent and distinct eastward expansion fronts of a highly mobile carnivore, the coyote Canis latrans), to investigate patterns of genomic diversity and identify variants that may have been under selection during range expansion. Using a restriction‐associated DNA sequencing (RADseq), we genotyped 394 coyotes at 22,935 SNPs and found that overall population structure corresponded to their 19th century historical range and two distinct populations that expanded during the 20th century. 

Eastern Coyote in Maine














Counter to theoretical expectations for populations to bottleneck during range expansions, we observed minimal evidence for decreased genomic diversity across coyotes sampled along either expansion front, which is likely due to hybridization with other Canis species. 

Furthermore, we identified 12 SNPs, located either within genes or putative regulatory regions, that were consistently associated with range expansion. Of these 12 genes, three (CACNA1C, ALK, and EPHA6) have putative functions related to dispersal, including habituation to novel environments and spatial learning, consistent with the expectations for traits under selection during range expansion.

Eastern Coyote in North Carolina











Although coyote colonization of eastern North America is well‐publicized, this study provides novel insights by identifying genes associated with dispersal capabilities in coyotes on the two eastern expansion fronts.

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