The thermal biology of the white-tailed rat Mystromys albicaudatus, a cricetine relic in southern temperate African grassland.

This study examines the hypothesis that Mystromys albicaudatus, a cricetine relic in southern Africa, has thermal characteristics typical of a rodent adapted to a cold temperature regime. Metabolic rate (oxygen consumption) of M. albicaudatus was measured using open-flow respirometry at ambient temperatures ranging from 5 degrees C to 35 degrees C. Lowest specific oxygen consumption was 1.352 +/- 0.089 ml O2 g-1hr-1 (n = 8; body mass = 93.78 +/- 6.27 g) at 25 degrees C, equivalent to 121.8% of the predicted value of Kleiber (1975), 128.8% of the value predicted for eutherians and 113.7% of the value predicted for cricetidae (Hayssen and Lacy, 1985).