SREL Reprint #3852

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

Grace Rogerson1, Samantha Bock2,3, Yeraldi Loera4, Benjamin Parrott2,3, and John F. Mulley1

1School of Natural Sciences, Bangor University, Deiniol Road, Bangor, Gwynedd LL57 2UW, UK
2Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
3Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802, USA
4Department of Ecology & Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA

Abstract: 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.

Keywords: Stripe formation, Incubation temperature, Alligators, Climate change, Sex reversal, Temperature-dependent sex determination

SREL Reprint #3852

Rogerson, G., S. Bock, Y. Loera, B. Parrott, and J. F. Mulley. 2023. Incubation temperature alters stripe formation and head colouration in American alligator hatchlings and is unaffected by estradiol-induced sex reversal. The Company of Biologists 226(6).

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).