I received what I think it a Teddy Bear hampster (has semi-long fur, with sections of his fur that are gray and stick out farther than the rest of him) from a friend who could no longer care for him. I got a new cage since his old one was too small. I got one of the white wire ones that sits on top of a 10 gallon aquarium. I have owned hamsters in the past, so knew that I would be able to care for him correctly. I've had him about three months, but I woke up this morning and he was laying on his side, looking pretty dead. I noticed right before I left for work, but had to get to work due to a project deadline. Here is some background on his recent behavior, and I'm hoping you might be able to help me determine what the cause of death was so that it does not happen with my next hamster. By the way, he was about 1 year old.
     I went on vacation for 4 days but made sure he had plenty of water and food. Ever since I returned from vacation, he has been very "bitey" and extremely active. He was doing this dare-devil thing by climbing the wire part of the cage, and going monkey-bar across the top. He falls often (far trip in my opinion, think two 10 gallon tanks stacked on top of each other), but always got back up and started it again. Do you think he fell last night, went into shock and died?
     Next, he was chewing on the bars NON-STOP the past few weeks, even with chew sticks available to him. Could the paint coming off of the bars as he chews cause his death? Doubtful, but I'm reaching for anything here!
     Finally, I also noticed when I got back that it looked like someone had trimmed off all of his long gray hairs (the ones I described above). Of course no one trimmed them, but I can't quite explain why all of them disappeared. There were 6 total tufts, right behind the ears on each side, and then on each side mid-way down his body, and then one on each side by his rear. Could this somehow relate to his death? And if not, what might be the cause?
    Again, I woke up this morning and he was laying on his side not moving. I really want to know what happened so that I can make sure it does not happen with the next hamster I get.
     Thanks for your help, I appreciate it!