Cultural Knowledge Explains Humanity's Ecological Success
But what does it mean when so much of it is now discovered, stored, and iterated on via platforms like YouTube and TikTok?
Hey everyone! I hope your week is going well.
I am back in Chicago as of Monday, having spent the last week in California with my mom. It was beautiful out there. It usually is.
Before I left, I picked up The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter, by Harvard anthropologist Joseph Henrich. The book is a contrarian effort to explain humanity’s ecological success, and it’s fantastic. I’ve read parts of it before, but wanted to give it a second look. I find that I can make more connections between the real world and what I read after I’ve read it a second time.
Writing this essay helped me grapple with Henrich’s argument. I open the essay pulling heavily from Henrich to outline it.1 Writing the essay also made me realize that this essay ends up asking more questions than it answers.
The main one: How does the way in which a platform like YouTube allows information to flow affect the people who consume it?
I hope you enjoy it.
Cultural Knowledge Explains Humanity's Ecological Success
“Evolution is cleverer than you are.”
—Leslie Orgel
In The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter, Harvard anthropologist Joseph Henrich argues that our species’ unprecedented ecological success cannot be explained by our individual intelligence.
Instead, he argues, our success is a result of our ability to learn from one another.
This refutes the hypothesis that our species’ success is a result of our individual abilities to adapt to our often hostile environments. Though having once pitched a tent in the rain might have you think otherwise, it turns out we—and, by extension, you—are not very good at this.
The first case study Henrich offers is that of Sir John Franklin.
In 1845, the British tasked Franklin—a seasoned Arctic explorer—with finding the Northwest passage. Doing so would supercharge global trade by connecting Western Europe and East Asia. Franklin and his 105 men set out in the summer of 1845, outfitted with two ice-breaking ships—the HMS Erebus and HMS Terror—and five years worth of provisions.
Things went as planned until the summer of 1847. The ice, which had trapped them in the winter of 1845 and melted in the summer of 1846, froze again in the winter of 1846, but didn’t melt in the summer of 1847. Around the time Franklin realized they’d be stuck at least until the summer of 1848, he died. This left an experienced Arctic officer named Crozier in charge. In the spring of 1848, after just shy of two years stuck on ice, Crozier ordered his 105 men to abandon ship and set up camp on nearby King William Island.
The record of what happened next is fuzzy, which makes it only slightly less ugly. Inuit reported encountering a band of the men and attempting to offer help before noticing that they were transporting human limbs.2 Crozier, Henrich notes, is rumored to have encountered an Inuit tribe and lived out his remaining days hiding from the shame of association with cannibalism. He is the only one suspected to have survived.
Of course, while cannibalism is deplorable, maybe it’s not surprising that Crozier’s men ended up resorting to it. It isn’t like the Arctic is a hospitable climate, after all. That said, the Inuit have thrived there for tens of thousands of years. If they could do it, Henrich asks, why couldn’t Franklin’s men?
Henrich’s answer to this is that Franklin’s men didn’t possess the necessary cultural knowledge accumulated by the Inuit. He writes:
“None of [Franklin’s men] figured out how to use driftwood, which was available on King William Island’s west coast where they camped, to make the recurve composite bows, which the Inuit used when stalking caribou. They further lacked the vast body of culture know-how about building snow houses, creating fresh water, hunting seals, making kayaks, spearing salmon and tailoring cold-weather clothing.”
Henrich dives deeper into the complexity of these techniques later in the chapter. Suffice it to say we shouldn’t be surprised that Franklin’s men failed to develop them. It likely took the Inuit generations to perfect them; the idea that Franklin’s men could do the same in a matter of months is absurd.
Years later, the British sent another expedition to find the Northwest Passage.
Henrich explains how this group, led by a man named John Ross, ran into a similar problem as Franklin’s. They, too, set up camp on King William Island. Unlike Franklin’s 105 men, though, all of who are assumed to have perished, Ross’s survived for three years on the island.
The secret to their success was simple. They befriended the Inuit.
This allowed them to take advantage of the Inuit’s accumulated cultural knowledge. This included methods of hunting, sealing, and sledding, among many others, all of which the Inuit honed over tens of thousands of years amidst the seemingly inhospitable Arctic terrain.
This is nothing ground-breaking here; that a crew friendly with locals in a hostile environment would do better than one that wasn’t should surprise no one. What is notable, then, is not how Ross’s group survived the Arctic, but how the Inuit did.
The answer is the same mechanism that Henrich proposes has given way to humanity’s unprecedented ecological dominance: “cultural evolution.”
He writes:
“We can survive because, across generations, the selective processes of cultural evolution have assembled packages of cultural adaptations—including tools, practices, and techniques—that cannot be devised in a few years, even by a group of highly motivated and cooperative individuals.”
To understand exactly what “cultural evolution” means, it’s worth understanding how evolution works.
For years, I believed—incorrectly—that evolution happened “to” us, like growing or aging. This is wrong. Evolution does not happen to us. Evolution happens slowly, constantly, all around us—and we are not as much a part of it as we think.
When we reproduce, our offspring are born with genetic mutations. These mutations are best understood as symptoms of our bodies failing to make perfect copies of themselves during reproduction.
Sometimes, mutations do nothing. Other times, they give way to slight changes in our physiques, or our behavior. These traits are then tested. If they make it easier for us to survive long enough to reproduce, they’re more likely to be passed down to the next generation, and become more common throughout the human gene pool. If they make it harder, they’re less likely to be passed down.
Henrich argues that this same mechanism is at work within cultures.
Take something like a chocolate chip cookie recipe that’s been passed down through generations. One day, while following it, you accidentally double the amount of butter in the recipe. The cookies emerge from the oven as hard as rocks. Your addition of butter is a “mutation,” but the “trait” it birthed would guarantee you’d never share it, because the cookies you just made are inedible.
You try again, though, and this time, you follow the recipe perfectly. The cookies emerge from the oven looking and smelling like they always do. Wishing they were sweeter, though, your daughter takes what she thinks is sugar from the counter and sprinkles it over them. You watch, thinking it might improve them. As she finishes, though, you realize she wasn’t actually sprinkling sugar over them, but salt. You rush over to brush it off, but the cookies are hot, and the salt is melting. Oh well, you think, I’ll just make another batch. Before you can toss them, though, your son walks into the kitchen.
“What’d you make?” He asks, eyeing the cookies. Before you can answer, though, he’s tossed one in his mouth.
“Mmmmm…” He says. “What did you add to these? They’re insane!”
Though a bit of a cartoon version, this is not far from how cultural evolution happens. A random event occurs and tweaks the normal way of doing something. If that method is worse, it’s discarded, forgotten. If it’s better, though, it’s passed on, and may come to dominate, whether it’s within a family, a community, or a company.3
Still, while this example gets at how natural selection improves how we do things, it doesn’t explain why we are so good at learning from one another. Fortunately, this is Henrich’s main argument.
He writes:
“The central argument of [the] book is that relatively early in our species’ evolutionary history, perhaps around the origins of our genus (Homo) about 2 million years ago, we first crossed this evolutionary Rubicon, at which point cultural evolution became the primary driver of our species’ genetic evolution.”
Several million years ago, Henrich proposes, mutations that improved our abilities to learn from one another suddenly became more evolutionarily useful than those that made us bigger, or stronger. This created a sort of flywheel effect.
As groups of humans collected more and more cultural knowledge, natural selection was forced to select for brains that could acquire, process and iterate on that knowledge. This led to an acceleration in the accumulation of said cultural knowledge, which would’ve further caused natural selection to select for mutations that would make it easier for us to acquire and make use of knowledge, ad infinitum.
Today, we see the results of this flywheel effect in everyone—even infants.
One particular study out of Seoul National University is telling. In the study, researchers brought in a group of mothers and their infants. The researchers selected three categories of toys to which infants typically reacted in one of three ways: positively, negatively, or with uncertain curiosity. Once the infants had gotten comfortable in the laboratory setting, they were shown the toys from each category with their mother in the room. The results were what you might expect. Infants looked at adults four times more often when they were presented with an unfamiliar toy than when they were presented with a familiar one, approaching the toy positively if the adult showed happiness, but backing off if they showed fear.
Put another way, under uncertainty, infants used social learning.
There is plenty of other data supporting our species’ use of social learning, but almost more compelling is the plethora of anecdotal evidence. When babies fall—say, out of a high chair—parents are often told to smile or clap, instead of rushing to their child’s aid with a concerned look on their face. The same logic at play in the lab is at play here; the joke is that humans figured this out likely centuries before the lab did. Under uncertainty, babies take cues from their parents. If parents don’t appear frightened, their baby might not, either.
As we get older, our use of social learning becomes more and more sophisticated.
By the age of three, Henrich notes, we are not only able to use social learning to make decisions, but are able to decide who to learn from. That is, by the age of three, we are able to judge adults’ competence, and adjust our attention accordingly. We retain this ability into adulthood and beyond, leveraging it in all kinds of contexts. Aspiring salespeople will often seek out the high performers at their company to learn what made them successful. Athletes do the same.
This sheds more light on what allows humans to make use of serendipity, like adding salt to finished cookies. Critically, realizing that adding salt to a finished cookie makes it taste better doesn’t happen in a vacuum; said knowledge might well be used later to improve another dish, or otherwise diversify the tools at some chef’s disposal.
As a species, then, it is not just our ability to learn from one another is unparalleled—it is our ability to establish a baseline of cultural knowledge, then iterate on it.
Each iteration that gives way to a method less useful than the original is discarded; each that gives way to one that’s more useful is embraced.4 Over a generation or two, a culture’s progress via this method might seem at worst sluggish, and at best incremental. But give it 30,000 years, and a mere baseline of cultural knowledge can evolve into a de facto encyclopedia.
This, of course, is what happened with the Inuit. Ross’s group survived on King William Island because they took advantage; Crozier’s died because they didn’t. It’s that simple.
When most of us think of collected cultural knowledge now, we don’t think of fashioning fish hooks, or using polar bear fur to stay warm through the winter. Most of the cultural knowledge we possess doesn’t even seem like knowledge, to the point that it can be difficult to even see what another culture might identify as our “cultural knowledge.”
Still, although it is fascinating to compare the knowledge accumulated by different cultures throughout history, it is arguably more interesting to think about the ways in which cultures transmit the knowledge they possess.
This, of course, is what I started thinking about when I went out in search of a piece of “cultural knowledge” a week or so ago, and found myself on YouTube.
The day after I moved into my condo in Logan Square, my cat knocked the gate remote off the top of my refrigerator and onto the hardwood, where it exploded.
I found the remote in pieces, its motherboard and drop switches exposed. Having received the remote with no instructions other than the implicit “press the button,” I didn’t take a second glance at the drop switches. I simply snapped the pieces of plastic back together, figuring I’d fixed it.
An hour or so later, needing to open the gate, I walked outside with the remote and pressed the button. The gate didn’t budge. I pressed it again, and again. Nothing. Exasperated, I did what anyone my age would probably do: I pulled out my phone and typed “how to fix gate remote” into Google.
This led me to YouTube.
Now, YouTube is a lot of things: a home for stupid cat videos, a repository of strange conspiracies, a collection of music videos. But above all, what I’ve found it to be, at least for the past several years, is a home for all of these bits of information that you might only ever need once, but that when you need them, you really need them. Videos on how to change your tire, say, when you get a flat in a rough neighborhood. Videos on how to fix your refrigerator which went out after you loaded it up with trays of catering for your daughter’s baby shower tomorrow. Videos explaining the IS-LM model to a college senior who has a comprehensive exam on it in six hours and hasn’t given it a second thought in two years.5
I’ve landed on YouTube countless times seeking information I’d have traded an arm and a leg for. And it’s hard to escape the conclusion that there are likely a lot of other people who would’ve, at some point, been in a position like this, too, not least among them the second-in-command-turned-captain Crozier, whose mission to find the Northwest Passage culminated in organized cannibalism, all because he never figured out a way to take advantage of the cultural knowledge accumulated and honed by the Inuit.
Now, of course, there’s YouTube.
To be clear, I don’t really mean to say that the cultural knowledge the Inuit honed over 30,000 years could simply be uploaded to YouTube, then fully absorbed by a foreigner. (It couldn’t.) Still, the broader truth is worth noting: that is, YouTube has become a de facto collection of cultural knowledge that I’m not convinced has a modern equivalent, or at least not one that’s even close to as searchable and user-friendly.
Consider that videos on YouTube with some variation of the word “beginner” in the title got more than 9 billion views in 2020.6 Globally, 82% of people used YouTube to learn to do something themselves.7 For a more tangible statistic, early on in the pandemic, there was a 458% increase in daily views of videos on how to make sourdough bread. What is worth noting about this figure, however, isn’t so much that it’s so high, but rather that it’s so low. It seemed like everyone kicked off 2020 preserving their sanity with sourdough. It’s thus a commentary on how relevant YouTube already was as a place people went to learn to make bread that even when the pandemic began in earnest, and everyone else fled there to learn, it was **only** ~4.5x as many people as normally would’ve.
And it’s not like YouTube is a “hub of online manuals,” either. What I find so incredibly frustrating about manuals and FAQs is that the questions they answer are almost never the questions I actually have. YouTube is different, because it’s driven by an algorithm. I won’t try to outline the technical details (because I don’t know them), other than to say that the algorithm knows what someone has clicked on, watched, and perhaps “liked” after searching for something similar to what you’re searching for. It’s not hard to see why this does a better job than, say, a manual, at helping you solve whatever problem you have. Further, even if the video in question doesn’t answer your question, the comments sections might actually contain useful insights (i.e., “if this video didn’t answer your question, try this one,” etc.).
On cooking tutorials, it’s hard to escape the conclusion that comments—“I substituted olive oil for butter!”—are, themselves, mutations, which can then be tested by readers and either embraced or discarded. If someone aggregates all the tweaks to the recipe, they might end up with a completely new one, which they could then post in a new YouTube video.
If that video blows up, then that is, well, cultural evolution.
Of course, there’s plenty to decry about YouTube. As a hub of cultural knowledge, though, I’m not sure it has an equivalent. Here, it’s worth returning to Henrich.
Millions of years ago, Henrich proposes, natural selection did a sort of “fork,” whereby it began selecting for cognitive power over physical strength. This led to the flywheel effect he outlines: natural selection chose brains with more cognitive power, which led to humans that could better process, store, and iterate on information. This created more information, which raised the premium again on cognitive power, ad infinitum.
If this did happen; if, millions of years ago, the “fork” Henrich proposes did actually occur, YouTube and its contemporaries—and, perhaps, the internet more broadly—would appear to be another one.
Like a book, YouTube functions as a sort of cloud storage for our cultural knowledge. It could be that this frees us up to focus on higher-order pursuits; in theory, it seems to make sense that if I don’t have to remember how to program a gate remote, I can focus on other, more interesting things. Still, I’m not entirely convinced that’s the case. Humans are not iPhones. Knowledge compounds, and it’s possible that offloading a meaningful portion of it will have some as-of-yet unseen effect on us.
The more pressing question, of course, is whether we’re willing to admit just how extensive humanity’s cultural knowledge actually is. The reason for this is simple: if society’s cultural knowledge is uploaded to YouTube, it isn’t just tutorials and funny videos. It’s ugliness. It’s pain. And the friction inherent in accessing it is zero.
Here, it’s worth returning one final time to Henrich.
There is a bitter root native to the tropical regions of the Americas called manioc.8
Manioc contains cyanide, a deadly poison. Eating too much of it causes cyanide poisoning. And yet, there is no evidence of chronic cyanide poisoning among those who first domesticated manioc.
The reason for this, Henrich points out, is the lengthy and labor-intensive process of preparing manioc, developed by societies such as the Tukanoan in the Amazon. This process takes several days, and involves scraping, grating, and washing the roots. This separates the fiber, starch, and liquid. Once done, the liquid is boiled, but the fiber and starch must sit out for two more days, after which they can be baked and eaten.
Like many traditions, the original reason for the process’s difficulty might not be readily clear, even to the Tukanoan.9 This, Henrich notes, might lead a younger member of the society to question the whole ritual, and wonder if there might be a better, more efficient way to go about it. That younger member, after all, would never have seen anyone get cyanide poisoning, because—as Henrich is keen to note—the lengthly, labor-intensive process of removing it works.
Attempting to shorten the process, though—say, by boiling the manioc—would remove the bitter taste, but it would also leave a non-trivial amount of cyanide in the manioc. Assuming you didn’t revert to the old method, in subsequent years, this cyanide would build up in people’s bloodstreams, eventually poisoning them.
As it turns out, something like this did happen happen. In the 17th century, Henrich notes, the Portuguese brought manioc to West Africa. What they didn’t bring was the method of preparing it. Because manioc was easy to plant and provided robust yields, even amidst infertile soil, it spread rapidly.
To this day, cyanide poisoning remains a health problem in Africa.
Now, YouTube and its contemporaries could end up being nothing more than blips. The way information flows via the platform, though, does bear a certain resemblance to the manioc the Portuguese brought to West Africa.
Free of the constraints that once governed it—or, put another way, the way it was once “prepared”—information can now travel virtually anywhere, instantaneously. We tend to ignore how a platform like YouTube enables information to move in favor of noticing what information is moving, even as the former is more profound than the latter.
On YouTube, people get answers to their questions faster, but they can also confirm their own biases faster, or access false and misleading information faster. This isn’t to say YouTube is a net bad for society, but it is to say wonder out loud if we are perhaps too focused on finding new and better ways of doing things, and not focused enough on understanding why we’ve always done things a certain way.
“Evolution,” as evolutionary biologist Leslie Orgel is quoted saying, “is cleverer than you are.” Admitting this will inevitably bring up questions, but if we fail to ask them, it’ll take more than a YouTube tutorial to solve the problem.
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By the way—my gate’s closed. I fixed the remote using YouTube. The floodgates, though… well, those are wide open.
Instead of citing him every time I paraphrase him, I’ve resigned myself to a footnote here. I also mention his name throughout the essay.
Sources say that skeletons of Franklin’s original 105 men were discovered in the 1990s with cut marks on the bones, appearing to confirm reports of cannibalism.
Notwithstanding what might happen in a company if someone came up with a better way of doing something that threatened some incumbent stakeholder with a vested interest in doing it a different way. In that case, a “better” way of doing something might fail to be realized, not because it wasn’t better, but because it was—and someone with both power and a vested interest in maintaining the status quo knew it.
Of course, it’s never quite this black and white, but like with evolution in nature, over tens of thousands of years, the most useful mutations do end up proliferating.
This one is personal; you can probably tell.
You can imagine Crozier finding a video titled: “Beginner’s Guide to Avoiding Cannibalism on King William Island!”
It is also known as “Cassava” or “Yuca” depending on where you are and who you’re talking to.
If this seems unlikely, it’s because you are unaware of just how many behaviors, if questioned, you’d rationalize with: “I’ve just always done it that way.”