I advise people not to mix species, however having them inthe same room is not typically a problem. (I do agree withGypsy about the mice though.) I have ferrets, rabbits andrats all in the same room. The ferrets are absolutely notallowed out with the other critters because they are natural predatorsand very fast moving and even if they weren't going to try to hurt therabbits, they would definitely think binkies were an attempt at the"wild weasel dance" and jump on them playing. The rats tendto sit on my shoulder fairly happily, so they can be with me when therabbits are out, but I would never leave them unsupervised.
Unlike Malo how has experienced territorial gerbils, I tend to thinkthey are much less territorial then hamsters. Hamsters aresolitary animals and can be very aggressive to other animals who invadetheir space. Gerbils live in family groups and make wonderfullittle families. I've kept males together and femalestogether. In fact, I'd never recommend keeping a solitarygerbil. Most recently I had 3 males together, but I used tobreed and you can keep multiple females together and they help eachother with the babies. It's really very cute. Youcan also keep daddy with the mom and babies as he won't hurt them likea hamster or rat would.
If you have any gerbil questions, I'd be happy to help. (Proper caging includes sand, just so you know.)
Jen
