If you've ever been unable to find a bathroom in a moment of need, you know the gotta-go feeling. That's nothing compared to the wood frog, which doesn't urinate all winter. In Alaska, wood frogs go eight months without peeing. And scientists have now figured out how they do it, or more accurately, how they survive without doing it. Recycling urea — the main waste in urine — into useful nitrogen keeps the small frogs alive as they hibernate and freeze, inside and out. It protects cells and tissues, even as the critter's heart, brain and bloodstream stop. The frogs can do it because special microbes in their guts recycle the urea, said a study in the Proceedings of the Royal Society B. "This is stress that would definitely kill any mammal," Jon Costanzo, a zoologist, said. "People are fascinated by bear hibernation, but in my book any animal that allows itself to freeze solid and is able to recover from it and walk away and thus go about its business like nothing happened, to me that's about as cool as it gets."

Elephants walk may also be a kind of talk

With a trunk that produces 110-decibel blasts that can be heard for miles, elephants are well-equipped for long-distance communication. But it turns out they may be letting their feet do some of the talking, too. Using tools designed for detecting earthquakes, researchers found that different elephant activities — walking, running, snorting, grunting — create distinct "seismic signatures" in the ground. In some cases, said a study in the journal Current Biology, these vibrations travel farther through the ground than they could through the air, giving the animals a variety of powerful methods for long-distance communication.

News services