Today I watched two male Ruby-throated Hummingbirds (Archilochus colubris) try to poke each other to death at my birdfeeder. This species of hummingbird is famously aggressive, with males fiercely protecting their favorite food source. These same two birds will stay here for the rest of the summer fighting over my feeder. When autumn sets in, they will begin their migration south, making their way to Central America - flying up to 2,000 kilometers without stopping. Unfortunately, when they do stop to rest, they will inevitably fight with other hummingbirds for access to food. These two will probably scrap all the way to Belize, and then spend the winter pummeling each other at someone else’s birdfeeder.
On one hand, this system of constant fighting is totally insane. There is more than enough food in my feeder to keep these two birds fat and happy for the entire summer. But their territorial food defense instincts are too strong to override.
From the perspective of natural selection, however, nothing is insane about this. Members of the same species are, by definition, likely to have identical food and shelter requirements. These overlapping needs mean that they will often find themselves in the same location attempting to access the same resources, so within-species (intra-specific) aggression is both likely and logical.
There are, of course, plenty of social species where individuals collaborate to optimize access to resources, like we see for ants, termites, bees, and other eusocial insect species. Or species that stick together in groups for safety, like wildebeest, cows, or horses. Or species like lions, dolphins, or meerkats that increase their individual chances of survival by living and hunting in groups. But even for social animals like these, there is a fair amount of fighting both within and between members of a social group. The study of sociality in animals has been supremely helpful in our understanding of how natural selection works, and inter- and intra-group fighting (even to the death) is often part of normal sociality.
But humans, which are also a social species, are famously able to override the evolutionary forces that would normally generate the kind of fighting that we see in our great-ape relatives like chimpanzees. Our chimpanzee friends typically live in groups of a couple dozen individuals, with the largest community of chimpanzees ever recorded being about 200 individuals. Fights between rival groups are common, and sometimes deadly. Humans, on the other hand, live in villages and towns and cities consisting of thousands or even millions of individuals who co-exist peacefully most of the time. When it comes to living in mind-blowingly large social groups, humans are unexpectedly chill (given our biology).
“If you take 10,000 chimpanzees and cram them together into Wembley Stadium or the Houses of Parliament, you will get chaos,” writes Yuval Noah Harari in Sapiens. “But if you take 10,000 people who have never met before, they can co-operate and create amazing things.”
This is a miracle of the human condition; a testament to our capacity for rational thought and language, allowing us to generate, discuss, and codify (through law or scripture or self-help books) an ethical worldview that extends empathy and moral worth to those well outside our immediate family or friend-group.
But, as we know from watching the news, it does not take much for humans to re-ignite the kind of intra-specific violence that smolders away in our genes.
What strikes me is how dishearteningly similar the human behavior I see on the news is to the unconsidered and seemingly unnecessary hummingbird violence outside my window. The recent anti-immigration riots in the UK are, at their heart, a response by people who feel that their in-group (i.e., fellow “Britons”), are at risk of losing something (access to health care? food? housing?) by allowing too many other non-British humans to live near them.
This completely normal human response is, again, exactly the kind of thing natural selection might favor – a potentially advantageous (for our genes) fight over access to identical and/or limited resources. Although in the case of the UK riots, the resource issue is more strawman than reality. On paper, our planet has the resources to provide enough food, housing, medical care, etc. for everyone not just in the UK, but every human on the planet. It’s only a matter of supply logistics preventing us from allowing universal resource access.
Logistics, and, of course, our biology.
We remain a species that is not genetically designed to want to help every human on the planet. Not even the most social of animals alive today – eusocial insects like bees – are designed for this level of global magnanimity. Rival colonies of bees will fight each other to the death over access to resources (nesting sites, flower patches), just like rival groups of chimpanzees or humans. In the case of humans, we seem to fight each other even if there’s plenty of food to go around - just like hummingbirds.
These Sunday-morning thoughts of mine are hardly revelatory. Surely I am not blowing your mind by noting that humans have a propensity for violence. We all know this is what humans are like. We know what the triggers are that can get us to fight each other. We know the fatal power of in-group vs out-group rivalry.
But there’s something about watching these two hummingbirds fight that brings it all home for me. If their brains possessed the cognitive capacity, they could easily decide to stop fighting and share their food. There is enough sugar water for the both of them. But their minds evolved to make them fight. And they will keep up this fighting from the shores of Nova Scotia to the rainforests of Belize. I mean geez, the whole world is open to them - either of these two angry boys could decide to fly 2,000 kilometers in any random direction and never have to deal with each other again. My neighbor across the valley has a hummingbird feeder with no hummingbirds at it. Just go there FFS! But their minds are narrowed by natural selection. They can’t help but fight.
Humans, on the other hand, need not be narrowed. We can stop ourselves from fighting. Global peace is possible for us. But we must first accept that out brand of sociality is no different to that of other species: it is equal parts empathy and violence.
How we achieve global peace and universal resource access through global structural, social, or political change remains a mystery. But on an individual level, my advice is this: don’t be a hummingbird, my friends. Fight your DNA, not your neighbors.
Share the sugar water.
***
Books I’ve read recently that I recommend are the Zoey Ashe series by Jason Pargin, and A Good Girl’s Guide to Murder by Holly Jackson (now a Netflix series). I also just got a copy of Do I Know You? A Faceblind Reporter's Journey into the Science of Sight, Memory, and Imagination by Sadie Dingfelder, which is on my bedside to-read pile. I’d also like to recommend my pal Angus’ Substack, Experiments in Pith. He’s a superb and thoughtful writer!
brilliant, Justin - as always
We are indeed hard-wired to want it all. We choose—generally—to override the firmware and establish civilization. That doesn’t mean the firmware isn’t still in place, only that we are running different software on top of it: the (thin) veneer of civilization.
Much has been written about what it takes to remove that veneer. Lord of the Flies by William Golding describes a hypothetical situation in which a ship carrying a bunch of British schoolboys goes down. No adults survive, so the island the reach is populated only by them. It’s not pretty.
Jared Diamond’s The Third Chimpanzee looks at chimp behavior as unveneered human interactions. It pretty much mirrors the way what passes for certain human “civilizations”have acted from time to time. Think: the Inquisition, Crusades, Nazis, large parts of the current arab world. The behaviors are aberrant not because they are unnatural, but because they run counter to whatever it was that caused us to establish societies in the first place.
Recall Kipling’s observation that “nature is red in tooth and claw.”
And there’s the problem. It is anti-natural to be civilized. But without a cohesive civilization, humanity dies off rapidly. Small groups of us aren’t going to have enough food to survive. There are many things in a jungle that you can eat to stay alive. There are also many things in the jungle that can eat you to stay alive.