Vue lecture

Do Reptiles Have Moods, Too?

Long dismissed as unintelligent, reptiles are emerging as cognitively and emotionally complex animals. A new study involving tortoises suggests that they also possess mood states.

© Federico Rios for The New York Times

A wary red-footed tortoise. In tortoises, neck extension is an indicator of relaxation; the farther the animal sticks its head out, the less anxious it is likely to be.
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