Incubation temperature alters stripe formation and head colouration in American alligator hatchlings and is unaffected by E2-induced sex reversal.

Considerations of the impact climate change has on reptiles are typically focused on habitat change or loss, range shifts, and skewed sex ratios in species with temperature-dependent sex determination. Here, we show that incubation temperature alters stripe number and head colouration of hatchling American alligators (Alligator mississippiensis). Animals incubated at higher temperatures (33.5˚C) had, on average, one more stripe than those at lower temperatures (29.5˚C), and also had significantly lighter heads. These patterns were not affected by estradiol-induced sex reversal, suggesting independence from hatchling sex. Therefore, increases in nest temperatures as a result of climate change have the potential to alter pigmentation patterning, which may have implications for offspring fitness.