Researchers say sloths aren't lazy, they're just "energy efficient." (Photo illustration: Yahoo News; photo: Getty Images) Magill says that by examining these “lazy behaviors,” humans might learn how ...

Today is International Sloth Day, a moment for the world to stop and appreciate the exquisitely strange gift that is the sloth. Below are some of the things you need to know to truly appreciate ...

They’re slow, they're sedentary and they like to sleep. Sloths are widely known as the world’s laziest animal but are they getting a bad rap? NBC’s Stephanie Gosk gets up close and personal with ...

The sloth may seem lazy, but its ancestors were anything but. In this video, evolutionary trade-offs reveal how energy efficiency replaced strength, transforming a once-powerful creature into one of ...