In The Mirror, Again

My YouTube feed sent me another goodie recently. The title was something about animal warfare and it opened with that Fallout quote — "War, war never changes" — before pivoting to the paper just published in Science about a chimpanzee civil war in Uganda. It was a reasonably good summary and I watched the whole thing. What it mostly did was make me want to write this post, which I have been pondering for a couple of weeks now since the study broke.

Because this is not new territory for me. I have been looking into this particular mirror since long before I started this blog. Chimpanzee culture and behavior have always caught my eye for some reason. A natural curiosity. Jane Goodall’s first book gripped me in my college years.

In 2009 I wrote about a BBC Planet Earth segment narrated by David Attenborough — extraordinary HD footage of 150 male chimpanzees in Uganda organizing themselves into a raiding party and attacking a neighboring group's territory. Several were killed. An infant was passed from chimp to chimp after the battle and eaten, almost ceremonially, down to the skeleton. I watched it with Jennifer and kept saying “his is just like 2001. The Dawn of Man. Apes fighting over scarce resources, killing for territory and dominance, doing things we had always told ourselves were uniquely human.” I wrote then that war has always been with us. That it is as natural an expression of our humanity as belief in deities or the need for love. The chimpanzees of Uganda were a mirror. In them I saw the familiar face of the highest primate of all.

Then on January 6, 2022 to be precise, the one-year anniversary of the Capitol riot, I returned to the mirror. I had just read about the Gombe Chimpanzee War, Jane Goodall's Four-Year War in Tanzania in the 1970s. A single community split. The northern Kasakela faction sent out war bands to systematically ambush and eliminate the Kahama males one by one. They did not fight at the border. They hunted. They celebrated afterward, hooting and dragging branches in what observers described as something resembling a victory dance. By 1978 the Kahama community had been completely eradicated. Writing about it on the anniversary of January 6, I found I couldn't separate the mirror from the moment. "The more hardwired Primate Brains," I wrote, "are ready to use violence against their political opposition." Trump had tapped something ancient. Something encoded. The Gombe civil war suddenly felt familiar.

Now there is a third war (that we know of). And this one might be the most disturbing of the three.

The Ngogo chimpanzee community in Kibale National Park, Uganda, has been studied continuously since 1995. It was the largest known wild chimpanzee community ever documented — roughly 200 individuals at its peak, living in smaller social clusters but functioning as one group. They hunted together. They mated across cluster lines. Researchers took videos of males from different clusters holding hands. For twenty years this community represented something like a proof of concept: a large, stable, complex primate society held together by overlapping bonds of kinship, friendship, and mutual interest.

Then in 2014 several older males died of disease. Not alpha males, not dominant figures in any obvious sense. What they were, researchers would later determine, were bridge individuals — the ones whose social relationships crossed the internal divides, who connected otherwise separate clusters to each other. With them gone, the network began to gradually polarize.

A new alpha male rose in 2015. Leadership transitions create instability in chimpanzee communities as surely as they do in human ones. Then a respiratory epidemic in 2017 took additional lives, several of them also connective figures. Each loss was another severed thread in a web that had held 200 animals together for two decades.

(Think of all our distant ancestors who died of all manner of epidemics precisely this way.)

The visible break came on a single afternoon: June 24, 2015. Primatologist Aaron Sandel of the University of Texas was observing the Western cluster when he noticed them go suddenly silent upon hearing the Central cluster approaching nearby. Nothing unusual about the sound — they had been hearing each other for years. But the Western chimps didn't go to meet them. They grimaced. They reached out to touch each other in what observers recognized as reassurance gestures — the way chimps comfort each other when frightened. Then they fled. The Central chimps chased them. The two groups avoided each other entirely for the next six weeks.

"I can pinpoint it to one particular day," Sandel said. "They were acting as if they were hearing outsider chimps." They weren't outsiders. They had groomed each other. They had held hands. Something had shifted inside the social network, invisibly, and on that June afternoon it became visible.

By 2017 the two groups occupied entirely distinct territories. What had been the center of a shared home range had become a border. In 2018 the killing started. The first documented lethal attack was on an adolescent male from the Central cluster named Errol. Over the following years the Western faction carried out at least 24 coordinated raids. Seven adult males killed. Seventeen infants. At least fourteen other adult males simply disappeared — no signs of illness, no bodies recovered. The researchers believe most of them were also killed. By 2026 the confirmed death toll stands at 28, with attacks still ongoing. Sandel has noted additional raids in 2025 and 2026 beyond what the Science paper covers.

Here is the detail that the YouTube video rightly emphasized and that I haven't been able to stop thinking about. The Western group was outnumbered three to one. Seventy-six animals against roughly two hundred and thirty. They were the smaller faction. They have been winning decisively. The Western group has grown from 76 members to 108 while the Central group has suffered what researchers soberly call a "stepwise decline." The New York Times called it the bloodiest chimpanzee conflict ever recorded.

They won outnumbered three to one because of internal cohesion. Because the fracture that destroyed the community as a whole forged the Western group into something tight and lethal. Between 2018 and 2024 they organized up to fifteen patrols every four months. They found isolated Central males and overwhelmed them with coordinated attacks — biting, pounding, dragging, kicking. They were not fighting at the border. They were hunting. The same tactics the Kasakela used at Gombe fifty years ago. And beginning in 2021, as at Gombe, they began killing infants.

I wrote in 2009 that the infant cannibalism I saw in the Attenborough footage seemed cultural rather than necessary. No material need explained it. It seemed to serve something psychological in the group. I still think that. There is a logic to infant killing in these raids that is military as much as anything else: you eliminate the next generation of fighters. You demoralize the enemy. You signal total commitment to the destruction of the other group. Humans have done exactly this throughout recorded history, up to and including the present century. The mirror does not flatter.

What makes the Ngogo war new, and more disturbing than the Gombe war or the Attenborough raid, is what the researchers call the relational dynamics hypothesis.

At Gombe, some scientists argued — and still argue — that human interference distorted chimp behavior. Goodall's team had used feeding stations, provisioning the animals with bananas. Maybe the aggression was an artifact. The Ngogo community was studied passively, with no feeding stations, no provisioning, minimal human interference. This war happened on its own. And it happened without scarcity triggering it, without territorial encroachment from outside, without competing ethnic groups or religious ideologies or ancient grievances. The forest at Kibale was rich. The group was well-fed. What collapsed was the social network itself. And when the social network collapsed, the killing followed as night follows day.

"Even without ethnicity, religion, or political ideologies," lead researcher Sandel said, "social networks can divide, leading to collective violence." Former friends become enemies on the basis of which side of the new line they happen to be standing on. Nothing more is required.

I have been looking into this mirror since 2009. Each time I look, the reflection is clearer and more specific than the last. In 2009 the mirror showed: we make war. In 2022 it showed: we are already doing it, and the ancient wiring is being activated right now. In 2026 the mirror is showing me the mechanism. Not just that civil war happens. Not just that communities fracture. But exactly how it works, stripped of every variable we normally use to explain our own violence away.

Remove the bridge individuals. Let the network polarize. Watch what was the center become a border. The rest follows without ideology, without scarcity, without any of the stories we tell ourselves about why this time is different, why our conflict is justified, why we are not like the apes.

The hopeful note I reached for in 2022 — the dying chimpanzee smiling at her old keeper, the kindlier side of the primate brain — I won't pretend it has gotten easier to reach. It is still true. The capacity for reconciliation is in the same brain as the capacity for organized lethal violence. Sometimes the bridges hold.

But in Kibale National Park right now, the Central chimps are taking a stepwise decline, and the bridge individuals are gone, and there is no sign the war is ending.

That’s what I see in the mirror now. This is a hardwired part of our brains as well as theirs. These chimps have been killing like this for thousands of years. And so have we.