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Biology

How Incubation Temperature Determines Sex in Reptiles

Quick fact

In the American alligator, eggs incubated at 30°C (86°F) all hatch as females, while those at 33°C (91°F) all hatch as males—a difference of just 3°C flips the entire sex ratio.

Why this is interesting

What if your sex were determined not by your genes, but by the temperature of your surroundings? For many reptiles, this is exactly what happens.