Kissing emerged over 21 million years ago, study suggests - Tech Explorist

June: Hey there, and welcome to Kindred Minds. I'm June — primatologist, science storyteller, and someone who genuinely cannot stop thinking about how extraordinary our primate relatives are. Every episode I bring you true stories about the minds, the lives, and the biology of our closest cousins on this planet — and today's lineup is one of those episodes where I just kept stopping and going, "wait, wait, wait, you have to hear this." We've got a bonobo who changed science forever, apes who tease each other just to be annoying, a brand new monkey species with the most spectacular lips you've ever seen, and a question about kissing that goes back over twenty million years. Plus, I need to share something urgent about two primates teetering on the edge of existence. But first, a huge thank you to our sponsors — Ada, who helps businesses and clients integrate A I into their workflows in smart, practical ways; Ago Consulting — that's "Ahh-Go" — your go-to for silicon development consulting, from A I all the way to SoC; and Zen Semiconductor, an umbrella company with an impressive portfolio across the silicon industry. These partners make this show possible, and I'm genuinely grateful. Alright — let's get into it, because the through-line today is one I love: how alike we truly, deeply are. June: So let's start with cognition — with what primate minds can actually do — and I want to begin with a name. Kanzi. If you've spent any time around primatology or language research, you know that name. And if you don't, I want to introduce you, because Kanzi the bonobo was, without exaggeration, one of the most remarkable individuals — and I use that word deliberately — that science has ever had the privilege of knowing. Kanzi passed away recently at the age of forty-four, at the Great Ape Trust in Iowa, and the loss was felt across the entire field. Scientific American covered his life and legacy, and reading it, I just kept thinking: this story has to be told again and again, because people still underestimate what it means. June: Here's how Kanzi's story begins. Researchers in the 1980s were trying to teach a bonobo named Matata to use a lexigram board — a board covered in symbols, each one representing a word or concept. Matata wasn't particularly interested. But her infant son, Kanzi, was sitting nearby during all these sessions, watching, absorbing. And when researchers eventually tested little Kanzi on the lexigrams, almost as an afterthought, they discovered he had already learned them. On his own. As a baby. Just by watching. June: That moment reoriented a lot of assumptions about language acquisition in non-human primates. Kanzi went on to learn hundreds of lexigram symbols — over three hundred, in fact. He could combine them in novel ways to express new ideas. He understood spoken English well enough that researchers had to spell things out around him so he wouldn't catch on to what they were planning. Think about that for a second. They were spelling things out. Like you do around a very perceptive child. June: But here's the part I find just breathtaking. Kanzi also learned to make stone tools. Researchers showed him how early hominins might have knapped flint — striking stones together to create a sharp edge — and Kanzi figured it out. He made functional cutting tools with his own hands. Now, he developed his own technique that differed from what he was shown, which some researchers found even more interesting — it suggests he wasn't just copying, he was problem-solving, adapting, innovating. The line between "us" and "them" just keeps getting harder to draw clearly, and Kanzi spent his whole life making that abundantly clear. June: What strikes me most, though, isn't the lexigrams or the tools. It's what people who knew Kanzi describe about his personality. He had preferences. He had humor. He had moods. He loved marshmallows and chasing people through the woods and watching movies — he had favorites. He was an individual. And he lived forty-four years, which is a long life for a bonobo, and he shaped our understanding of primate minds in ways that will last generations. Rest well, Kanzi. Science owes you a debt it can never fully repay. June: Now, if Kanzi made you think about the serious, profound depths of primate intelligence, I want to pivot to something that is also scientifically significant but also just... delightful. Because it turns out that great apes are absolute menaces. In the best possible way. June: Research covered by Smithsonian Magazine looked at teasing behavior in great apes — chimpanzees, bonobos, gorillas, and orangutans — and what they found is that apes deliberately, intentionally provoke each other. They poke. They prod. They snatch things and then look at the other ape to see the reaction. They dangle objects in front of others and yank them away. They wait for a response. They repeat the behavior. And crucially — and this is the key scientific detail — they watch for the reaction. That's not just play. That's not just roughhousing. Watching for a reaction to a deliberate provocation is the hallmark of genuine teasing. It requires a theory of mind. It requires understanding that the other individual has an experience — a frustration, a feeling — and that you caused it, and that you find that interesting or funny. June: The researchers argue that this urge to annoy, this impulse to tease, has roots that go back millions of years — predating the split between humans and our great ape relatives. Which means the next time a kid pokes their sibling in the car just to get a reaction, you can tell them with complete scientific accuracy that they are expressing an evolutionary impulse millions of years old. That probably won't help. But it's true. June: What I love about this research is that it fills in a picture of ape social life that feels so much richer than the old textbook version. These aren't just animals responding to stimuli. They're navigating relationships, testing boundaries, playing social games. They have a sense of humor — or something so close to it that the distinction starts to feel like splitting hairs. And when I watch footage of a young chimpanzee dangling a stick in front of an older one and then bolting, cackling — well, not literally cackling, but you know what I mean — I think: I know that energy. I have met that energy in every playground I've ever visited. June: Alright — thread two. Our shared recipe. The biology that binds us. And I want to anchor this in something that happened over twenty-one million years ago. Because a new study — picked up by Tech Explorist — suggests that kissing, as a behavior, may have emerged that long ago, in the common ancestors of the great apes and Old World monkeys. Twenty-one million years. That is staggering. June: Now, when researchers talk about kissing in this context, they're looking at lip-to-lip contact as a social behavior — observed in chimpanzees, bonobos, gorillas, and other primates — used for greeting, for reconciliation after conflict, for bonding and affiliation. It's not identical in every context to a human kiss, but the gesture, the neural architecture behind it, the social function — these appear to be deeply, anciently shared. June: And that's the key thing I want you to hold onto. These behaviors aren't coincidences. They're not primates accidentally doing something human-looking. They arise from shared biology — from the same ancient evolutionary recipe that built us and built them. When we share roughly ninety-eight to ninety-nine percent of our D N A with chimpanzees — and the numbers are close for bonobos, and not far off for gorillas — what that means in practice is that the developmental programs, the neural wiring, the hormonal systems, the social instincts — they're built from nearly identical instructions. June: Think of it like a recipe. If you and I are baking from recipes that are ninety-eight percent the same, our cakes are going to have a lot in common. The texture, the structure, the way they rise. The one or two percent difference might give yours a slightly different flavor — or a different shape — but you'd recognize them as the same kind of thing. And what this research on kissing suggests is that even some of our most intimate, most human-feeling behaviors — the ones we tend to think of as uniquely ours — are actually written into a recipe that was set down millions of years before Homo sapiens ever existed. June: This matters because it reframes how we think about ourselves. We are not a departure from nature. We are a continuation of it. We are the latest chapter in a story that started long before us, written in the same molecular language, expressed through the same ancient emotional and social drives. The urge to press your lips to someone you love — that might just be twenty-one million years of biology saying: I am safe with you. I belong with you. And that impulse, in some form, predates our species entirely. June: And I want to build on that by talking about D N A and what it actually means to share it in the proportions we do. Because I think the numbers sometimes wash over people — ninety-eight percent sounds like a lot, but it's abstract. So let me try to make it vivid. The human genome contains something in the range of three billion base pairs. Ninety-eight to ninety-nine percent similarity with a chimpanzee means that the differences we're talking about — the ones that make us human and make them chimpanzee — are scattered across roughly one to two percent of all those instructions. And in the grand sweep of life on Earth, that is an extraordinarily small gap. We are not separated from chimpanzees the way we're separated from, say, a fish or a fern. We are separated by a matter of evolutionary inches. The genes that govern how our brains develop, how we process emotion, how we form social bonds, how we learn — many of them are shared, sometimes nearly identical, between us and the other great apes. The story Kanzi told with his lexigrams, the story apes tell when they tease each other, the story lips-touching tells across twenty-one million years — it's all written in that shared code. June: Now I want to turn to the part of the episode that always means the most to me personally — a story that sits at the place where primate lives and human lives intersect in a way that just stops you cold. June: I need to talk about two primates whose futures are genuinely in peril. Mongabay News recently ran a deeply reported piece about two of the world's most at-risk primates — and the picture it paints is not easy to sit with. I'm not going to give you despair. But I am going to give you the truth, because these animals deserve to have their situation understood. June: Without being specific to one single unnamed species in the article — the pattern Mongabay describes is one we see again and again at the edge of primate survival: habitat loss, fragmentation, illegal hunting, the slow erosion of the forests and ecosystems these animals depend on, compounded by climate pressures that are shifting the landscape faster than populations can adapt. And when you are already a small, slow-reproducing species living in a specific forest in a specific part of the world — every hectare lost, every family group disrupted, every infant taken, matters enormously. These aren't statistics. These are individuals. Individuals with the kind of minds we've been talking about all episode. Individuals who form bonds, who grieve, who remember, who tease each other and press their lips together in greeting. June: And here's where a piece of genuinely wonderful news fits in — because the world of primatology doesn't only deal in loss. Sometimes it deals in discovery. ABC News in Australia recently covered the discovery of a new monkey species — a monkey with, and I love this detail, bright orange lips. Years of searching. Years of researchers in the field, following calls, collecting samples, cross-referencing genetics, and finally — a new species. Named and known. Added to the family tree. June: Every new species discovered is a reminder that there is still so much life on this planet we haven't fully met yet. And it is also, if I'm honest, a reminder of what we stand to lose if we don't protect the habitats these animals call home. The forests that hide undiscovered monkeys are the same forests being cleared. The urgency of conservation and the joy of discovery live right next to each other, always. June: But let me end this thread on something that gives me hope, because I think hope is load-bearing in this work. The fact that people spend years searching for a monkey with orange lips — years — and don't give up, tells you something. The fact that organizations like the ones covered in Mongabay's reporting are on the ground, working in incredibly difficult conditions, advocating for animals most people will never see — that tells you something. The fact that you're listening to this podcast, that you care enough to spend time understanding these animals and what they face — that tells you something too. June: We are the only species that can choose to protect the others. And that choice, I think, is one of the most important expressions of intelligence we have. Not the stone tools, not the language — though those are remarkable. But the capacity to look at another mind, across the distance of millions of years of separate evolution, and say: you matter. I see you. I'm on your side. June: Kanzi communicated across what people thought was an unbridgeable gap. Apes tease each other because they understand that someone else has an inner experience. We share lip-contact as a gesture of belonging across twenty-one million years. And somewhere in a forest that was recently still unknown to science, a monkey with orange lips is living its life, completely unaware of the human beings who spent years searching for it, who felt joy when they finally found it, and who now want the world to know it exists. June: That is kinship. That is the whole story. June: We are not alone on this planet, and we never have been. Intelligence is not ours alone. Feeling is not ours alone. The capacity to bond, to grieve, to innovate, to tease, to reach toward another face — these are not human inventions. They are primate inheritances. They are life's deepest patterns, expressing themselves through every branch of our shared family tree. I hope these stories stay with you — I hope they make the world feel a little bigger and a little closer at the same time. This has been Kindred Minds, brought to you by Ada, Ago Consulting, and Zen Semiconductor — partners who believe in curious minds and bold ideas. If this episode moved you, please subscribe, share it with someone who needs a little wonder in their week, and check the link in show notes for more on every story we talked about today. Stay curious, stay kind, and I'll see you next time.