Crocodiles Sleep With One Eye Open – Literally

Video highlights from Outback Wrangler

Aussie scientists have proven the ancient legend about the fearsome reptiles

Researchers have revealed evidence to support the ancient Aboriginal legends that crocodiles sleep with one eye open.

La Trobe University scientists found that crocodiles may engage in unihemisphere sleep – sleeping with only half of their brain at a time.

This behaviour would allow crocodiles to keep one eye open and connected to the awake side of their brain while the other half of the brain and the eye are sleeping, meaning they can more quickly respond to threats or nearby prey.

We’ve known for a while that some birds and marine animals engaged in unihemisphere sleep, but this is the first comprehensive study into crocodilians.

"These findings are really exciting as they are the first of their kind involving crocodilians and may change the way we consider the evolution of sleep," lead researcher Michael Kelly said.

"What we think of as 'normal' sleep may be more novel than we think."

Using a specially-adapted aquarium with infrared cameras, researchers observed crocodile behaviour day and night, including when humans and juvenile crocodiles were introduced.

The discovery is bad news for people like Outback Wrangler Matt Wright, who’ll have to take even more care as he relocates crocs around the Northern Territory.

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