Description:
The hypothesis that in tropical habitats sit-and-wait lizards should be more affected by seasonal fluctuations in food availability than active foraging lizards (resulting in seasonal reproduction in the former and continuous reproduction in the latter) was investigated using 13 lizard species from six localities at the Brazilian Cerrados and Amazonian Savannas. Using fat body mass as an indicator of food availability, we predicted that active foragers should exhibit larger values of fat body mass than sit-and-wait foragers during the dry season. Contrary to our expectations, sit-and-wait lizards displayed larger fat bodies than active foraging lizards, thus being apparently less affected by dry season reductions in arthropod abundance. We postulated that higher accumulation of fat in sit-and-wait lizards during the dry season results from a higher production efficiency than active foraging lizards, as a consequence of lower maintenance costs, and that reproductive seasonality is not constrained by food limitation.