What determines if animals of the same species will fight when they meet?

Question

What determines if animals of the same species will fight when they meet?

Answer 1

If one or the other thinks that its position (as alpha) is threatened then it will try and show dominance over the other.  What s*x they are also determines if they fight or not, usually two males will fight.  Territory is also another cause, if one animal of the same species crosses into anothers territory they will fight to show that this land is theirs.  Cannabilism is another cause, chimps will attack other troops of chimps and eat them.

Answer 2

Depends on how the group is co-ordinated. If they have to have an alpha male then they will fight if they think they are the strongest. They might also fight to defend there territory or over certain resorces if it is scarce.