Energy budgets were determined for adult female Anolis limifrons on Barro Colorado Island in Panama. Experiments were conducted in the early wet season when the oviposition rate is maximal. Old and young adults ingested 64 and 88 cal g'd-1 respectively, and assimilated 86% of ingested calories. Old adult females allocated 27% of assimilated energy to reproduction and fat contributed 8% of the caloric value of eggs laid. Young adult females allocated 11% of assimilated energy to growth and 11% to reproduction. During one year, an adult female allocates 23% of metabolizable energy to reproduction and 2% to growth and fat storage. In terms of fractional allocation of energy to maintenance, growth, and reproduction, the annual energy budget of A. limifrons is similar to those of temperate zone iguanids. In contrast, this tropical species has 1.5-3.5 times more energy per unit body weight that can be used for growth and reproduction than do the temperate species. Thus, the prediction from life history theory that A. limifrons should have a greater reproductive effort than temperate zone iguanids is supported by its absolute allocation of energy to reproduction and not by the fraction of its energy budget used for this purpose.