Why do hamsters eat their young?

I believe I've read somewhere one reason the mom will do that is if she thinks there's a threat to the babies. Also, if you don't provide adequate food and water, she'll think there's not enough for the babies and she'll eat them. I don't understand why they do that though, some kind of instinct they have. I would suggest, if you haven't already, separating the male and female so they DO NOT have babies. Otherwise, the babies will breed with mom and dad and each other, and you will very quickly have hundreds of hamsters. Males are ready to start breeding by about 6 weeks old, and females a few weeks after that. If you don't do that, and let her have another litter, be sure not to touch or disturb the babies or mom until they're at least 2 weeks old, and walking around on their own. Just leave them alone. And make sure there's lots of food and water for all of them.