Research led by the University of Exeter shows that some turtles are naturally heat-tolerant.
The study focused on green turtles on Ascension Island. They found that eggs laid by turtles on a naturally hot beach withstand temperatures better than eggs found on cooler beaches just a few kilometers away.
The warmer beach had dark sand and the cooler beach had white sand. Since most female turtles nest on the beaches where they were hatched, it was concluded that the turtles became adapted to specific nesting locations.
Adaptaition to heat
The researchers placed some eggs from each beach into incubators at either 32.5°C or 29°C and monitored the progress. They found the eggs from the warmer beach were better able to survive in the hot incubator than those from the cooler beach. Researchers believe that this is the first time that adaptation to local environmental conditions has been demonstrated in marine turtles.
Dr Sam Weber, who lead the study said, “Such adaptations probably evolve over many generations, so whether turtle evolution can keep pace with the rapid climate change that scientists have predicted remains to be seen. However, occasional movements of heat-adapted turtles to other nesting sites could help to spread favorable genes.” ■