I was watching Mythbusters, and the redhead girl says, "for this experiment, we'll be using rats because rats are self-aware and less likely to put themselves in danger." so I just had to look this up. turns out some people at the U of Georgia did some studies that seem to suggest this. (from Newsweek): I think it's pretty cool. All studies on animal intelligence fascinate me. So if anyone knows more studies along these lines I'd love to know about them... or videos. I watched a BBC doc on chimps a few months ago (can't remember the name) that was awesome.