Largest dataset of ape cognition offers new clues to human intelligence - Earth.com

June: Welcome to Kindred Minds — I'm so glad you're here. I'm June, a primatologist and science communicator, and this show is my favorite thing in the world: sharing true stories about our closest relatives, the other primates, in a way that makes you feel just how close they really are. June: Today's episode is brought to you by some brilliant sponsors. Ada, who helps clients integrate A I into their workflows in ways that actually work. Ago Consulting — that's "Ahh-Go" — silicon development consulting from A I all the way to SoC. And Zen Semiconductor, an umbrella company with a portfolio across the silicon industry. Grateful for all of them. June: And today — oh, today is a good one. We've got chimpanzees being studied in the largest dataset of ape cognition ever assembled. We've got bonobos having imaginary tea parties. We've got new research flipping what we thought we knew about primate rationality. And a story that's going to make you feel something — about who we're sharing this planet with, and what we owe them. Let's go. June: So let's start with something that genuinely stopped me in my tracks when I read it. A team of researchers has put together what is now the largest dataset of ape cognition ever collected — and I want you to sit with that for a second, because that's not a small thing. We're talking about decades of data, multiple species of great apes, thousands of cognitive trials, all pulled together into one place. And what they found is already reshaping how scientists think about the origins of human intelligence. June: Here's the question at the heart of this research: what makes human intelligence distinctive? For a long time, the prevailing idea was that we humans have some kind of special cognitive package — a bundle of abilities like causal reasoning, theory of mind, and complex tool use — that appeared together, all at once, kind of like a switch got flipped somewhere in our evolutionary history. The implication was that this package was uniquely ours. June: But when you actually look at the data — and I mean really look at it, systematically, across species, in controlled conditions — a more complicated and honestly more beautiful picture emerges. The cognitive abilities we think of as distinctly human? Many of them show up in the other great apes too. Not in identical form. Not to the same degree in every domain. But they're there. The building blocks are there. June: Chimpanzees, bonobos, gorillas, orangutans — they all demonstrate sophisticated problem-solving, they understand cause and effect, they track what other individuals know and don't know. These aren't parlor tricks. These are foundational capacities. And this new dataset lets researchers compare them in a way that was never really possible before — rigorously, at scale. June: And then there's the rationality piece, which got its own dedicated study out of the University of California, Berkeley — and I love this one. The question researchers were asking was: do chimpanzees make decisions the way a rational agent would? Do they weigh options, update their beliefs based on evidence, and choose consistently? And the answer — carefully arrived at through controlled experiments — is a pretty compelling yes. June: Now, I want to be precise here, because this is important. We're not saying chimpanzees reason about abstract philosophy. We're saying that when faced with choices — especially choices that involve uncertainty and probability — chimpanzees show behavior consistent with rational decision-making. They're not just reacting. They're evaluating. They're computing odds, in a sense. And that's a remarkable thing to observe in a non-human animal. June: What I love about both of these studies together is that they don't just tell us something about chimpanzees. They tell us something about us. Because if the cognitive roots of rationality, of planning, of understanding other minds — if those roots reach back before the evolutionary split that gave rise to humans, then intelligence isn't something that appeared out of nowhere. It grew. Slowly, over millions of years, in a family of animals we're still part of today. June: And that is the story of cognition — not a bolt from the blue, but a slow, shared flourishing. June: Now let's talk about the biology underneath all of this. Because the cognitive similarities we just talked about don't exist in a vacuum — they exist because we share something profound at the molecular level. I'm talking about D N A. June: You've probably heard the statistic before: humans and chimpanzees share somewhere around ninety-eight to ninety-nine percent of their D N A. And I know that number can start to feel abstract if you've heard it a few times. So let me try to make it feel real. June: Think of your genome — all your D N A — as a recipe book. A massive one. Billions of letters long, with instructions for building every protein your body will ever make, every cell type, every organ, every nuance of your immune system, your brain, your hands. Now imagine that a chimpanzee's recipe book is almost identical to yours. Not similar the way cousins might look alike. I mean almost letter-for-letter the same, for the vast majority of the text. June: The differences — that one to two percent — are real and they matter. They account for differences in brain development, in language capacity, in certain aspects of metabolism. But here's the thing: those differences are written in a book that is otherwise almost identical. Same chapters, same ingredients, same fundamental logic of life. June: And it's not just chimpanzees. Gorillas share roughly ninety-eight percent of their D N A with us. Orangutans, a bit less — around ninety-six to ninety-seven percent. Even that feels startlingly close when you think about how different an orangutan looks and lives from a human being. But open up the recipe book, and you'll find the same basic instructions running the show. June: This is why when researchers study the neurobiology of apes — how their brains develop, how neurons connect, how stress hormones work, how social bonding is mediated by oxytocin — they keep finding the same systems, the same molecules, the same ancient machinery that we find in ourselves. The ape brain and the human brain are not two different inventions. They are variations on a single, ancient design. June: And that design was shaped by millions of years of living socially — in groups, with relationships, with the need to read other minds, to cooperate, to compete, to care for young. Long before humans existed, the evolutionary pressures that built our kind of intelligence were already at work in our primate ancestors. What we call "human" cognition is, in a very real sense, primate cognition that kept going in one particular direction. June: So when you see a chimpanzee comfort a grieving companion — and they do, researchers have documented this — you are not watching something that merely resembles human empathy. You are watching the same biological system, built from the same recipe, expressing itself. That's not metaphor. That's molecular reality. June: I find that breathtaking. I find it humbling. And I find it full of responsibility — which brings me to the third story I want to share with you today. June: I want to tell you about Kanzi. And then I want to tell you about something that's happening right now that we all need to know about. June: Kanzi was a bonobo — and I say was because he passed away in 2024 at around forty-four years old, which is a remarkable age for a bonobo. For decades, he lived at the Great Ape Trust in Iowa, and he became one of the most studied and, I think, most remarkable non-human animals in recorded scientific history. June: Kanzi learned to communicate using a keyboard of symbols called lexigrams — and he didn't just learn to ask for food, the way you might train a dog to sit. He used those symbols to refer to things that weren't present. He talked about the past. He made requests for the future. He invented combinations of symbols to describe things he didn't have a word for. He learned to understand spoken English. Not just tone — actual words, actual sentences. June: And then there's the tea party story, which was written up beautifully in Smithsonian Magazine. Researchers wanted to know whether apes could engage in pretend play — the kind of imaginative, symbolic thinking that in human children we see emerge around age two or three. So they sat down with Kanzi and they had an imaginary tea party. Pretend cups, pretend tea, pretend pouring. And Kanzi played along. Not robotically, not through imitation alone — but with what looked, unmistakably, like genuine engagement in a shared fiction. June: He would hold the invisible cup. He would pretend to sip. He would offer pretend tea to the researchers. And what the scientists were seeing was something that, before great ape research, we thought was the exclusive province of the human imagination: the capacity to hold a symbol in mind and treat it as if it were real. To enter a world that exists only in the meeting of two minds. June: This is the kind of finding that doesn't just add a data point to a table. It changes how you think about the boundary between "us" and "them." It asks you to look at a bonobo and realize that the inner life in there — the imagination, the social intelligence, the desire to connect — is not a pale imitation of ours. It's the same fire, burning in a different form. June: And that is exactly why the next story matters so much to me. Because right now, the World Wildlife Fund is reporting that primate trafficking — the illegal capture and sale of wild primates — is surging on social media. People want these animals as pets, as novelties, as content. And so poachers are going into forests, tearing infant primates away from their families — families that grieve, that form bonds that last a lifetime, that play imaginary tea parties — and selling them online. June: Infant primates that appear in videos or photos as cute little pets almost always got there through violence. The mother is usually killed. The troop is disrupted. And the animal that survives — if it does — is traumatized in ways we now know, from the biology, are profound. Because they have the same stress systems we have. The same attachment systems. The same capacity for grief. June: I'm not trying to make you feel bad. I'm asking you to see clearly. And seeing clearly means knowing this: if you ever see a primate being kept as a pet or featured in social media content as a novelty, the most powerful thing you can do is not share it, not like it, and report it. Don't engage with it. Engagement is what the algorithm rewards. Silence and reporting are the tools we have. June: Kanzi played imaginary tea parties. The infants being traded online right now are his kin — genetically, cognitively, emotionally. They belong in forests, in families, in the wild lives they were built for. June: We share the recipe. And that means we share the responsibility. June: Here's what I keep coming back to, as I think about everything we talked about today. Intelligence — real intelligence, the kind that plans and imagines and empathizes and plays pretend — that didn't begin with us. It grew slowly, in a family of animals we're still part of. The great apes are not a rung below us on some ladder. They're our cousins, shaped by the same evolutionary pressures, carrying the same ancient D N A, living in the same world we've always shared. June: When a chimpanzee makes a rational choice, when a bonobo pours imaginary tea, when a gorilla grieves — those aren't moments that make us feel superior because we recognize them. They're moments of recognition because we're reading family. We're reading ourselves. June: Kindred Minds is brought to you by Ada, Ago Consulting, and Zen Semiconductor — three teams of humans building the future with their own kind of intelligence, and I'm grateful for their support. June: If today's episode moved you or made you curious, please subscribe, share it with someone you love, and leave a review — it genuinely helps more people find the show. And for all the studies, the sources, the WWF reporting on primate trafficking, and more on Kanzi's remarkable life, you'll find everything at the link in show notes. June: Stay curious. Stay kind. And I'll see you next time on Kindred Minds.