Meet the "Snot Otter," North America's Biggest Salamander

If you've splashed around in the creeks of Appalachia, you may have been close to the largest salamander in North America, the Eastern hellbender, but you probably wouldn't have known it. Learn about this magnificent critter in a short documentary produced by Freshwaters Illustrated and the US Forest Service. » 10/24/14 5:35pm Friday 5:35pm

Size Matters: Narwhals With Longer Tusks Have Bigger Testicles

Narwhals grow long tusks, if they have the balls to do it. The spear at the end of the male sea unicorn has been variously thought to be a sensory organ, a device for battling other males, or an elaborate reproductive signal. New evidence shows they're the whale version of peacock feathers. » 9/22/14 6:42pm 9/22/14 6:42pm