I have a question about my hamsters - Ryuuk and Rem. They have been with me for a year now since they were babies.

For the past couple of weeks, both of them have been fighting like mad and it's bloody. The first brutal fight I witnessed was when Ryuuk bit Rem near the neck and it was bleeding. I thought Ryuuk was culprit because he is scared of people touching him and will pounce on your finger and bite if you try to touch him.

But I was wrong, it seems Rem is the culprit because I started noticing that Rem is always initiating the fights and chasing Ryuuk around in the cage.

Now I have seperated them and both of them have scars because of the fight.

I would like to know why Rem has become so brutal and disliking Rem so much. Before this, they were ok. Although they did fight, but only for a couple of seconds then everything's back to normal with both of them sleeping beside each other. Now they can't even stay in the same cage. Is it some mid-life crisis thing because they are a year old now.

Thanks.