These things survived the Great Extinction and have essentially remained unchanged for well over 50,000 years. They're darn cute, too. This is a "toony" sort of version of the pika -- they're sort of a cross between a mouse and a bunny with big round ears, ratlike feet, and slightly longer legs than a rat (but shorter than a bunny.) Their mouth pouches are flexible; you can find the funniest pictures of these with their mouths stuffed full of vegetation.

Coat color varies. Many of them seem to turn white in the winter.