sudden fatal fight?

Question
I had 2 female pet rats, approximately 4 months old. They were purchased from the same pet store about a week apart and had always gotten along fine together in a large cage. They were very sociable, having been around children in a school setting frequently, and were introduced to other rats without any issues. Any tussles they had were completely normal--wrestling here and there, but never any bites. Today I discovered 1 dead on the cage floor, and (this is graphic) her face literally torn apart. It was one of the most horrifying things I've ever seen. This obviously happened while I was not there, perhaps the evening before while I was out.

I cannot for the life of me imagine what happened. In all my years of rat-keeping, I've never seen or heard of anything like this. I've owned mice before and have witnessed similar things when there are 3 or more mice. But never with rats. Have you ever encountered this kind of thing. I am at a loss for words!

Answer
I doubt that your rat died from the other rat.  This is why I always suggest a necropsy. Vets usually do NOT charge for one unless tissue samples are sent out.  You  would know if your rat died from natural causes such as cardiac arrest or an aneurysm.  I just cant see four month old rats, esp females that have usually been docile with each other.

I am almost as sure as I am sitting here that she died from something else and....as graphic as it sounds...it is actually a normal thing for other rats to consume their dead. Its actually an "honor" to their dead....a way to bury them, keep their bodies from predators and to protect their nests location in the wild.  If a rat is left dead, predators will come for the remains and may discover the rat colony so a proper disposal is necessary.  Usually the rats consume the abdomen and the head, or parts of it.

I am sorry you had to witness this.  As shocking as it seems, this is nature at work and the rats natural instincts kicked in, despite domestication.   Remarkable in many ways,misunderstood by others, but still it is fascinating the way these animals can think and reason things out the way they do.