> To the extent that they have good memory, they live in a world of finite resources, and their behavior was shaped by the forces of game theory as applied to tribes, this is more or less inevitable. You can read that as defeatism or just math. We can't overcome the force of game theory, but we can make it work for us by making our transactions increasingly transparent and repeatable, so that cooperation is more successful than defection.

Note that the conclusions of the paper, while acknowledging the problem of access to resources, are different. They also do not conclude that this is "more or less inevitable":

> The lethal aggression that followed the fission at Ngogo informs models of intergroup conflict. All observed attacks were initiated by the numerically smaller Western group, contradicting simple imbalance-of-power models that predict an advantage for larger groups. Persistent offensive success by Western males suggests that cohesion supported by enduring relationships can outweigh numeric disadvantage. Our observations are also relevant for predictions from parochial altruism. Because cohesion among the Western cluster preceded overt hostility, external threats may be unnecessary to foster cooperation. Cohesion among members of the wider Ngogo group, however, may have weakened when external threats from adjacent groups decreased after territorial expansion in 2009.

and

> This study encourages a reevaluation of current models of human collective violence. If chimpanzee groups can polarize, split, and engage in lethal aggression without human-type cultural markers, then relational dynamics may play a larger causal role in human conflict than often assumed. Cultural traits remain essential for large-scale cooperation, but many conflicts may originate in the breakdown of interpersonal relationships rather than in entrenched ethnic or ideological divisions. It is tempting to attribute polarization and war that occur in humans today to ethnic, religious, or political divisions. Focusing entirely on these cultural factors, however, overlooks social processes that shape human behavior—processes also present in one of our closest animal relatives. In some cases, it may be in the small, daily acts of reconciliation and reunion between individuals that we find opportunities for peace.

Which sounds kinda hopeful!

My own observations is that the preconditions for the split that led to open warfare between the two Chimp groups was:

1. The nonviolent (illness) death of a few key individuals that linked both groups, and...

2. The complete stop of interbreeding. Once the two groups stopped interbreeding, the split was finalized and they became truly hostile.

Stretching this a bit, it makes me think of those (usually white supremacists) who claim "multiculturalism" is to blame for all the world's problems, and if only every ethnic or religious group stayed in their lane and didn't mix with the other, we could all live in peace. But it seems to me the lesson from this paper is that this (isolating us in separate groups) would make the split complete enough that we would decisively start butchering each other.

Chimpanzees in Uganda locked in eight-year 'civil war', say researchers