Normal and abnormal behaviour in rats?

Itching isn't normal under any cirstances, if they look like they are itchy then they have something wrong with them, Abnormal - hiding not responding to you, Normal always happy to see you and greet you at the bars - Abnormal - spiked up hair/illness Normal - spiked up hair /showing domninance/making themselves look bigger Abnormal biting when never bitten before/illness Normal biting through hormonal aggression(needs a neuter) you see some same things can have two different reasons - I have done loads of research on the net and I am surprised that you say you found very little when I found tons & tons especially on the forums thats were the knowledglbe people are PS my lot have loads of things in their cage and they don't make use of very much of it, it isn't because they are displaying Abnormal behaviour its because they are all big fat lazy bucks, so I would knock no.4 off your list - GO TO GOOSEMOOSE pet portal ''Rats Rule'' can't go wrong