An external and cranial mophometric study of altitudinal variation in Microtus arvalis in Switzerland ...

• Main Author: Prescott-Allen, Christine
• Format: Text
• Language: English
• Published: University of British Columbia 2010
• Subjects: Common vole; Microtus arvalis
• Online Access: https://dx.doi.org/10.14288/1.0095479; https://doi.library.ubc.ca/10.14288/1.0095479

Cranial and external measurements in 422 museum specimens of the common vole, Microtus arvalis, from Switzerland were examined to determine whether they varied with altitude in accordance with either (1) Bergmann's Rule, or (2) subspeciation. Correlation coefficients between altitude and size were calculated on 32 dimensions, each of which had been divided into sex segregated age groups. In not one of the 108 tests was correlation significant. The lack of adherence to Bergmann's Rule was investigated by (1) reviewing the basic concepts of the Rule, as applied to homeotherms; (2) identifying the major abiotic and biotic selection pressures that might affect growth in Microtus arvalis, including climate and competition with sympatric congenerics; and (3) indicating deficiencies in data derived from museum specimens which might have influenced the computations. There were several references in the literature to the occurrence of two subspecies of Microtus arvalis in Switzerland - the nominate subspecies M. a. ...