Geographic Variation in Red-backed Mice (Genus Clethrionomys) of the Southern Rocky Mountain Region

Geographic Variation in Red-backed Mice (Genus Clethrionomys) of the Southern Rocky Mountain Region

This file was derived from scanned images.The original text and copies of the included illustration is presented.Clicking on the Map will allow the user to view a larger copy of the scanned image from which it was derived. In the course of the preparation of a synopsis of the North American terrestrial microtines by one of us (Cockrum), and the completion of a Master's thesis on the geographical variation of the red-backed mice of Wyoming by the other (Fitch) we had occasion to study the red-backed mice of the southern Rocky Mountain region (see figure 1). Results of these studies are the recognition of two heretofore unnamed subspecies of the red-backed mouse in the southern Rocky Mountain region, and a clarification of the taxonomic status of two additional kinds. Remarks.--C. g. galei, with the largest geographic range of any of the Rocky Mountain subspecies, is also the most variable. Three principal areas of geographic variation were found. These areas are: The mountains of north-central Colorado and southern Wyoming (this area includes the type locality); the Big Horn area probably northwest into Montana (no adult specimens from Montana or Alberta examined); and the Teton area which includes the mountains east and southeast of Yellowstone National Park. Specimens from these areas have noticeable differences in pelage, but no constant cranial differentiation could be detected. Specimens from the Medicine Bow Mountains of southern Wyoming have a more reddish dorsal stripe, and more buff and less gray on the sides than either of the northern geographic variants. The dorsal stripe continues farther anteriorly and is better defined through its entire length. There are fewer differences between the two northern[284] geographic variants than between either one of them and the southern variant. Specimens from the Teton Mountains, however, have grayer sides, and the outer margin of the ear is tipped with chestnut (little or no chestnut shows on the ears of the specimens from the Big Horn Mountains); the dorsal stripe is less distinct (with slightly more gray throughout) than in either of the other geographic variants of the one subspecies. ......Buy Now (To Read More)

Product details

Ebook Number: 32679
Author: Cockrum, E. Lendell
Release Date: Jun 4, 2010
Format: eBook
Language: English

Contributors

Contributor (Author): Fitch, Kenneth Leonard, 1929-