Torpor in the tropics: the case of the gray mouse lemur (Microcebus murinus)

The most extreme adaptations to seasonal food scarcity and low ambient temperatures are daily torpor and hibernation. Torpor is realized in the small malagasy cheirogaleids, Microcebus and Cheirogaleus. In the present overview, I reviewed information on daily and prolonged torpor of the gray mouse lemur ( Microcebus murinus). Specifically, I related the occurrence of seasonal changes in body mass, metabolic rate, body temperature and energy expenditure to changes in external conditions. Furthermore, I discussed the relation between seasonality and life history traits. This study revealed that torpor in this species may not only reflect its impact on the energy demands, but involve much wider adaptive implications such as water requirements. The function of torpor appeared to vary among individuals and has a strong influence on the population dynamics of M. murinus.