It stands to reason whether ants and chimpanzees wage war or show behavior patterns that are from a human perspective similar enough to what we call war, that we describe it as such.
Being a biologist, I think it's dangerous to ascribe uncritically things like 'language' to bees or 'waging war' to ants and chimpanzees. Not because it's leading to humans looking like animals, but rather because it's anthropomorphizing animals.
War, as we know it among humans, is something else than the behavior of bonobos and ants. War as humans wage it has to be understood as an actual, intentional and widespread armed conflict between political communities. The kind of conflicts over territory that chimpanzees fight out aren't really of the same category. Biologists describe them as 'wars' in analogy to human behavior. Just like physicists used to explain the Atom as a 'small solar system' back when Bohr's atom model was sota.
I know that nowadays there is a prevalence for using such analogies in the life sciences, but there is a problem with that: While only very few, confused, people would take the sentence "An atom is a really, really small solar system." to be meant literal, people do so if it's a sentence like "Chimpanzees wage war." and that's a problem. Still biologists go for such descriptions of animal behavior because they are popular, probably because otherwise very complex phenomena are thus broken down to a state where the usual listener thinks that he understood what chimpanzees are doing there.
So, do chimpanzees and ants conduct war? Not in the same sense as humans do. War is not only a category that describes a certain behavior of the animal species 'homo sapiens', but it's a term that implies an ethical dimension because it's meant to refer to something in which ethically responsible actors engage in. Thus, it has to be assessed from an ethical perspective.
Ethically speaking, war has little merit in itself. If we ask what is good about war, then we will inevitably come to the conclusion that everything we come up with to answer this question is something that war might lead to, but is external to war: Innvoation and creation? Nothing that is an exclusive feature of war. Re-evaluating (bad) ideas? We can have that without war as well. Interestingly in both cases we reap the real benefits only after the war ceased to be, that is, after peace has been established.
It turns out that war itself isn't something to be desired, even if some of it's effects might be desirable: Chiefly among these effects is the establishment of peace. Still, already having peace is indubitably better than establishing it.
So, while I wouldn't subscribe to the idea that war is 'the most evil thing humans do', as it can be under certain conditions be an ethical means to ethical ends, I'd say that war is never an ethical ends and thus should be avoided whenever possible.
It's evil to pursue war, even though it might be good to pursue peace through war. War, thus, might sometimes be what one might call "a necessary evil". One has to pay close attention to the conditions under which it is really necessary, though. I don't think that some elusive and speculative 'long, long term benefits' constitute such a necessity.
Tl;Dr: What Matoko said.