Hibernation in a tropical prim

Physiology: Hibernation in a tropical primate

KATHRIN H. DAUSMANN*, JULIAN GLOS†, JÖRG U. GANZHORN‡ & GERHARD HELDMAIER*

* Department of Animal Physiology, Phillips University, 35043 Marburg, Germany
† Department of Animal Ecology and Tropical Biology, Julius–Maximilians–University, 97074 Würzburg, Germany
‡ Department of Animal Ecology and Conservation, University of Hamburg, 20146 Hamburg, Germany


e-mail: dausmann@staff.uni-marburg.de




The Madagascan fat-tailed dwarf lemur, Cheirogaleus medius, hibernates in tree holes for seven months of the year, even though winter temperatures rise to over 30 °C. Here we show that this tropical primate relies on a flexible thermal response that depends on the properties of its tree hole: if the hole is poorly insulated, body temperature fluctuates widely, passively following the ambient temperature; if well insulated, body temperature stays fairly constant and the animal undergoes regular spells of arousal. Our findings indicate that arousals are determined by maximum body temperatures and that hypometabolism in hibernating animals is not necessarily coupled to a low body temperature