Wild gerbils are colored for camoflauge but modern gerbils come in every color but day glow. Check out some of the possibilities at The Gerbils Color Palette.
Different sources seem to disagree on exactly how many gerbil species there are. The gerbil most commonly kept as a pet or lab animal is the Mongolian Gerbil (Meriones unguiculatus) but it's certainly not the only gerbil. Another gerbil is the Duprasi or fat tailed gerbil (Pachyuromys duprasis). Lewis Stead has started a Duprasi FAQ.
A picture titled gerbil that was posted to alt.binaries.pictures.misc on 12/14/95. It's not your standard fur ball. It's a strange psychedelic mandala of a gerbil. (This picture is from Jeff Lundstrom's archive of several binary newsgroups.)
