Seasonally breeding animals, such as the green anole lizard (Anolis carolinensis), differ morphologically, physiologically and behaviorally between their breeding and non-breeding states. While non-breeding, anoles have regressed gonads, lower gonadal steroid hormone levels and decreased reproductive behavior compared to breeding lizards. Initially, non-breeding anoles enter a refractory period where reproduction is inhibited. After, a post-refractory period occurs where breeding can be triggered by appropriate environmental conditions. However, it remains unclear what morphological, molecular and behavioral parameters might differ across these two non-breeding periods. To address this, male anoles were examined during October (refractory) and early February (post-refractory), while visually isolated and maintained in the laboratory under the same non-breeding-like environmental conditions. Preliminary results revealed that post-refractory testes had a greater mass, greater volume, and whiter color (all p < 0.01, n = 8) compared to refractory testes. Interestingly, these results suggest that, independent of breeding-like environment conditions, time-dependent physiological changes are occurring that initiate the transition towards breeding. We are continuing to conduct analyses on reproductive behavior, gonadal and kidney morphology, as well as gonadal gene expression in these lizards to characterize any additional differences between refractory and post-refractory periods. In our study, we have seen that environmental stimulation is not necessary for the transition to a breeding-like state in this species. However, this raises questions regarding what potential molecular and/or physiological factors, independent of external cues, are required for the onset of breeding.