Maturity and Receptiveness or ready to mate, if they rapidly "twitch" their head from side to side upon seeing a female. If they do this, you should also notice color changes on the male's face and belly. Testing if a female is receptive is also as easy. You should not just put the female in the male's cage, but rather keep her on your hand so you can make sure the two will not fight. If she is unreceptive, she will usually turn black or darker than her normal colors, begin to rock her body back and forth, and gape, or open her mouth, at the male. If this happens, remove the female from sight of the male, and try again in a couple of weeks. You may notice that large males will shoot their tongues at small females to try to get them closer if they cannot easily reach them. After you find your pair is receptive and ready to mate, put the female in the male's enclosure. The mating process for chameleons can be quite violent sometimes, so do not be worried at the first sight of aggression. Males may be rough with the females by head-butting, grabbing, and pinning them down, but this is all natural. The most aggressive species we have