Pet rat burying the other

Question
We just got a new pet rat, did the neutral environment introductions, and during that, they got into a nasty scuffle. Now our first rat, is trying to bury the new guy into his home...why? do we need to separate them?

Answer
 If burying is all they are doing it should be just fine.  The rat being buried should be easily able to dig himself out.  I haven't seen this type of behaviour myself in males, though females will often rearrange nesting material when they are being territorial so maybe it is the same kind of thing.  It's normal for them to fight a little bit, but if they are viciously attacking each other, drawing blood, and constantly fighting you may have to separate them either for a short period and try to reintroduce them again later or leave them apart permanently.  Males can be tricky to introduce if they are older so don't feel bad if it doesn't work out; they will be just fine on their own.  I hope that answers your question, good luck with your rats!