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This is Scientific American's 60-Second Science. I am Karen Hopkin. It will just take a minute.
 
Picture a sloth¹ and what do you see? Some slow-moving, hairy beasts just hanging around, maybe even catching² some Zs, and that’s just your husband. OK, seriously. We've all seen films of three-toed sloths³,odd-looking creatures that spend their days hanging upside down in the rain forest canopy⁴. They move so slowly that mossy looking algae⁵ actually grow on them. And legend has it they sleep like 16 hours a day. But researchers from Germany and the US have found that sloth might not be the slugabeds we think. Using an equipment designed to monitor the brain wave of animals in the wild, the scientists found the sloth actually spend less then ten hours a day asleep in the trees. The results appear in the current issue of the Royal Society journal Biology Letters. Why the discrepancy⁶? While the earlier estimate comes from work done with animals in captivity⁷. And maybe in the sloths' sleep lab. There is not much to do besides snooze. In the wild ,on the other hand, the animals need to keep an eye open for potential predators⁸, like snakes or birds, and they also spend time foraging⁹ for food, because nobody bringing a sloth any breakfast in bed.
 
Thanks for the minute for Scientific American's 60-Second Science, I am Karen Hopkin.