Thermogenic capacity in subterranean mammals: insights from intraspecific analysis in Ctenomys talarum

LUNA F; ANTINUCHI CD

Congreso; XI International Mammalogical Congress; 2013

One of the central tenets of ecological physiology is the identification of selective factors influencing energy metabolism. In this sense, the convergent evolution of subterranean forms of life among mammals is a fascinating evolutionary phenomenon. Subterranean mammals often exhibit convergent morpho-physiological features that can be seen as adaptation to the subterranean environment. The aim of this study is to evaluate intraspecific variation in thermogenic capacity of the subterranean rodent Ctenomys talarum. We estimate non-shivering thermogenesis (NST) and cold-induced maximum metabolic rate (MMR) of individuals of 6 population of C. talarum separated each other ~150Km in grasslands of Argentina. Basal metabolic rate (BMR) was different (p<0.01), but neither NST (p=0.13) nor MMR (p=0.73) differed among populations. Similar NST could be related to thermal stability within burrows, but external Ta could be, at the same time, an important factor since cold-induced MMR was x 4 times BMR.