Glob. Change Biol. http://doi.org/4cc (2015)

Credit: © GEORGE H.H. HUEY / ALAMY

In most reptiles the sex of hatchlings is determined by incubation temperature, which is affected by environmental temperature. However, the sensitivity of this temperature-dependant sex determination (TSD) to climate change and potential effects on species persistence remain unclear.

Pilar Santidrián Tomillo from the Institut Mediterrani d'Estudis Avançats, Spain, and co-workers simulated the response of leatherback turtle populations to increasing nest temperatures and compared the results with a theoretical population with fixed (genetically determined) sex ratios. They found that leatherback populations with TSD could mitigate the negative effects of higher temperatures by increasing production of female offspring resulting in increased fecundity. However, the effective range of this TSD adjustment mechanism is limited so that projected temperature increases are still expected to yield a negative effect.