Energetics of the Southamerican subterranean Ctenomys rodents: Integrating different levels of understanding

LUNA F; ANTENUCCI CD

Mendoza, Argentina

Congreso; X International Mammalogical Congress; 2009

Maintenance of life requires a continuous flow of energy. Internal restrictions (i.e. digestive capacity), as external (i.e. environmental temperature) might determine the physiological responses of the individuals. The convergent evolution of subterranean forms of life among mammals is a fascinating evolutionary phenomenon. Subterranean mammals often exhibit convergent morphological and physiological features that can be seen as adaptation to the subterranean environment. In this broad context, species belonging to the genus Ctenomys are a valuable model to explore and understand several hypotheses related to energy acquisition and expenditure at different hierarchical levels (individuals or populations), since have a broad geographical distribution, occurring from 10º S to 55º S, in the southern cone of South America, can be found between 0 and 5000 masl, are all herbivores and inhabits a variety of habitats and climates, and contrary to other subterranean mammals, have an extensive use of surface food items. Even Ctenomys includes more than 60 extant species, these are relatively morpho-physiologicaly homogeneous, but differing markedly in body mass, ranging from 100 g (C. pundti) to more than 1000 g (C. conoveri). In this study we attempt to show the state of the art in the knowledge of Ctenomys energetics. Also we will relate different ecological patterns, such as distribution and abundance, to physiological and molecular mechanisms underlying them, hence to understand the physiological strategies of Ctenomys species to cope with subterranean conditions. Finally, by comparing the observed patterns with recent information of different mammals groups, we could give insights into the factors that influence the broad scale pattern of subterranean mammals energetics.