Many species, including humans, struggle to survive when temperatures rise too high. But even small increases can affect animals, causing subtle changes in physiology or behavior that alter how they fare.

For some lizards, the effects of heat may, somewhat literally, be a no-brainer. A new study published in Royal Society Open Science has found that a temperature increase on the scale expected from climate change can make bearded dragons dumber.

Bearded dragons are Australian lizards that have become popular as pets, and like other reptiles, they’re not as dumb as they might seem. “Reptiles were long considered to be sluggish and unintelligent creatures,” said Anna Wilkinson, an animal cognition scientist at the University of Lincoln in the U.K. But