A "crocodile smile" has long been used to describe someone who is intimidating and up to no good, but what if a true crocodiles smile actually meant he likes having a good time? New research has determined that top crocs are actually very playful creatures, riding waves, chasing balls, and taking piggyback rides just for fun! 

That's at least according to a study recently published in the journal Animal Behavior and Cognition, which details how observing crocodile play could help tip zoos how to care for these otherwise seemingly brutish animals.

It's no secret that play can be a powerful stress reliever. Past studies have revealed that mammals and even birds play, indicating that it is an essential part of life for healthy adult animals. A recent study also showed that play and hidey-holes alike can help cats quickly adapt to new and stressful environments, such as an animal shelter.

Now, this latest study has coupled professional field observation from anecdotal evidence and observation from croc-centric social media groups and zoos for more examples.

Vladimir Dinets, a behavioral ecologist from the University of Tennessee, Knoxville and the author of the study, found that crocodiles seem to participate in all three kinds of common play in particular: play involving movement, play with items, and social play.

Specifically, young crocs seem to enjoy playing with balls supplied by zookeepers or even debris floating in their habitats. Older crocs can be found surfing waves for no notable reason other than enjoyment, and large male crocs have even been found to give their female mates "piggyback rides" around their neighborhood - again, for no discernible reason other than for fun.

"Hundreds of thousands of crocodilians are now kept in captivity in zoos, commercial farms, and breeding centers set up for endangered species," Dinets added when speaking with Red Orbit. "Providing them with toys and other opportunities for play makes them happier and healthier."

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