When I first got Felix, he was very friendly and curious. He was reasonably comfortable being picked up and generally easier to handle than Basil, the gerbil I'd had for two weeks. Now that Basil and Felix are in the same cage, Felix has gotten really skittish. He wasn't this way when they were in the split cage. He stays in the nest box most of the time and when he does come out, he moves in a quick jerky way and dashes back to the nest if I make any quick movement--even if I'm several feet from the cage. If I put food in my hand sometimes he will eventually come out to get some, but he seems really scared the whole time. I didn't change anything about the way I handle him and I haven't tried to pick him up since this started. What happened to my friendly Felix? 



