Inside their territory, they will attempt to kill any other predator who could compete with them and who belongs to a weaker species. This is a necessary strategy, because any territory has a limited productivity and it cannot sustain too many predators that want to eat the same kind of prey. Thus predators either specialize into separate niches, e.g. some eat mice, some eat rabbits and some eat deer, or they kill each other if they want the same food, to eliminate the competition.
They will also attempt to repel outside their territory any predator of the same species with them. They will seldom attempt to actually kill a predator of their own species, but that mainly because this would be risky, as in a fight to death they could be killed themselves, so ritualized harmless fights are preferred.
The difference with some primates like chimpanzees and humans, is that competitors of the same species may be treated as other predators treat only predators from different, weaker species.
The reason might be that when you cooperate within a bigger team, you may have the same advantage against competitors that a stronger predator has against a weaker predator, e.g. a wolf against a fox.
Thus a fight to death may be chosen, because the bigger team has good chances to win the fight. So chimpanzees start wars for the same reason why Russia attacks Ukraine or USA attacks Iran, those who have more weapons and more money believe that they can win the war, so they start it.
Most other predators do not start wars against their own kind, because in a balanced fight the winner is unpredictable.
> Thus a fight to death may be chosen, because the bigger team has good chances to win the fight. So chimpanzees start wars for the same reason why Russia attacks Ukraine or USA attacks Iran, those who have more weapons and more money believe that they can win the war, so they start it.
In the two Chimpanzee "wars" discussed in Wikipedia (Ngogo and Gombe) it was the smaller group that started the aggression. They were objectively at a disadvantage, but managed to kill or drive off most of the chimps from the larger group. It's as if being focused on aggressive behavior was their advantage.
Smaller groups do not start aggression simultaneously against the entirety of a bigger group.
They seize the opportunity when a smaller group than themselves is separated from the remainder of the big group, and then they overpower the smaller group.
Then they repeat this until they eliminate the bigger group.
My point was that animals understand very well the advantages of belonging to the bigger group at the moment of starting a fight, and they will start the fight only when they estimate that they will win.
The same happens with other social predators. A big group of hyenas will harass or even kill other predators, like leopards or lionesses, which would make them run away when in a small group.
Humans and chimpanzees are probably better at planning a long-term strategy about how to use their advantage in numbers in order to eliminate rivals. Other predators might use their advantage in numbers when an opportunity happens, but they might not perform a surveillance of the actions of a neighbor community, to discover when it becomes possible to use the bulk of their mates against a smaller group of the neighbors that happens to be separated from the others during their foraging activities.
I don't disagree with anything you're saying, mind you! I'm just curious that in the two Chimp cases at the forefront of this conversation, the smaller group started the war. Yes, they of course attacked when they could find isolated targets, but still it seems more "planned" than simply chance and opportunistic attacks (as much as it makes sense to state Chimps planned this, of course).
As a comparison, and changing species, in the also mentioned Mapogo lion coalition (a similar "war" with lots of casualties), the attackers had the numbers, motive and power advantage: six "disenfranchised" male lions, healthy and powerful and experienced with tackling big game such as buffalo, which gave them an advantage when killing other lions (and yet they still chose to isolate victims first, because as you said, animals understand the principle of strength in numbers).
I'm not disagreeing with you on anything, just musing.
Inside their territory, they will attempt to kill any other predator who could compete with them and who belongs to a weaker species. This is a necessary strategy, because any territory has a limited productivity and it cannot sustain too many predators that want to eat the same kind of prey. Thus predators either specialize into separate niches, e.g. some eat mice, some eat rabbits and some eat deer, or they kill each other if they want the same food, to eliminate the competition.
They will also attempt to repel outside their territory any predator of the same species with them. They will seldom attempt to actually kill a predator of their own species, but that mainly because this would be risky, as in a fight to death they could be killed themselves, so ritualized harmless fights are preferred.
The difference with some primates like chimpanzees and humans, is that competitors of the same species may be treated as other predators treat only predators from different, weaker species.
The reason might be that when you cooperate within a bigger team, you may have the same advantage against competitors that a stronger predator has against a weaker predator, e.g. a wolf against a fox.
Thus a fight to death may be chosen, because the bigger team has good chances to win the fight. So chimpanzees start wars for the same reason why Russia attacks Ukraine or USA attacks Iran, those who have more weapons and more money believe that they can win the war, so they start it.
Most other predators do not start wars against their own kind, because in a balanced fight the winner is unpredictable.