What really separates humans from other animals? It’s one of the oldest questions we’ve asked — and the answer keeps changing. Tool use was supposed to be uniquely human. Then we watched crows bend wire into hooks and octopuses carry coconut shells as portable shelter. Language was supposed to be uniquely human. Then a bonobo in Des Moines invented the phrase “slow lettuce” to describe kale. The list keeps getting shorter.
In this episode, you’ll learn:
- Why the framework we use to define human uniqueness is built on a standard we designed ourselves
- Which items on the current “uniquely human” list are likely to hold — and which are already being challenged by research
- What elephant grief, crow behavior, and rat empathy tell us about animal cognition and emotion
- Why the question of what makes us different isn’t just biological — it has moral implications
- How our laws and ethics need to evolve as our understanding of animals deepens
Key Takeaway
Different doesn’t mean superior. And the list of what makes humans unique keeps shrinking. It’s time our actions and our laws caught up with what the evidence actually shows.
Episode Highlights
00:00 — Breaking the Mold: Penny Ellison introduces a philosophical episode questioning the foundations of animal advocacy
00:44 — Human Exceptionalism: Why humans separate themselves—and elevate their value—over animals
02:13 — Descartes’ Divide: How a philosopher’s cruel experiment justified centuries of animal suffering
03:06 — The End of Mind-Body Dualism: Science moves on, but our cultural hierarchy remains
04:05 — Debunking Uniqueness: Tool use, language, and other “uniquely human” traits—debunked by animal research
05:04 — Kanzi and the Whales: Case studies of animals that challenge our old assumptions
06:24 — The Shrinking List: As animal science advances, the supposed human-animal gap narrows
07:44 — Building Moral Hierarchies: How human-centric tests create the illusion of superiority
08:42 — Examining the Evidence: Revisiting Gretchen Rubin’s list of “uniquely human” traits
09:12 — Grief, Memory, and Shame: Animals display complex emotions—are we moving the goalposts?
10:47 — Rats and Empathy: Surprising research reveals moral decisions in non-human animals
12:05 — The Moral Challenge: Different doesn’t mean less—the ethical imperative to re-examine how we treat animals
Transcript
This episode is a little bit different. It’s not about a law or an issue in animal sheltering. It’s the foundation for all our thinking about animals and how we treat them. It’s about philosophy and an ethical approach to animals—all of them—and whether the way we treat animals is consistent with our beliefs about them. And especially whether there’s anything that reliably separates humans from other animals. So consider this one of those shorter, more conversational weeks I mentioned in my year-end episode about winemaking. Though I’ll be honest, it got a little longer than I planned. Some thoughts just won’t stay small.
Welcome to The Animal Advocate, where we arm animal lovers with the information and inspiration you need to become effective advocates. I’m your host, Penny Ellison, and I’ve taught animal law and advocacy at the University of Pennsylvania since 2006. If you’ve ever thought, “Someone should do something about that,” I’m here to guide you on your journey to being that someone. You can find us on the web at animaladvocacyacademy.com. And that’s where you’ll find show notes and resources, and you can send us your comments on episodes and ideas for topics you’d like to hear on future shows. So, onto today’s topic.
What makes us different from other animals? It’s one of the oldest questions humans have asked, and we’ve been getting the answer wrong for a very long time, because our understanding of animals keeps changing. We do things to animals that we would never do to humans: confine them in small quarters for their whole lives, use them for experiments, kill them. And most people, most of the time, don’t lose sleep over it. Why? Because we’ve decided we’re in a different category. Not just different—better. That idea has a long history.
In 1649, René Descartes watched a dog being cut open alive and concluded that the screaming didn’t mean anything. Because he had a theory. His theory was that animals are basically very sophisticated machines. They respond to stimuli. They make sounds, but there’s nobody home. No soul. No inner experience. So the screaming and the grimacing—that’s just gears like clockwork, not suffering. He called it dualism: mind and body are separate. Humans have minds; animals just have bodies. And that distinction, that one idea, gave centuries of scientists, farmers, and lawmakers a clear conscience.
We’ve moved on from Descartes. Nobody serious is arguing animals can’t feel pain anymore. We have animal cruelty laws. We use words like “sentience,” meaning the capacity to feel, to experience pleasure and pain, to have an inner life. And most scientists now accept that many animals have it—almost all of them. We’ve come a long way. And yet, we’re still drawing that line. We’re still looking for that thing that makes us categorically different. And not just different, different in a way that matters morally.
I listened to a podcast recently by Gretchen Rubin. She hosts the wildly popular Happier podcast. She’s a lawyer, a former Supreme Court clerk, and someone I really enjoy. And she made a list of all these things that are unique to humans. It’s an interesting list, and I don’t think she’s wrong that there are some real distinctions. But it got me thinking because we’ve had this list before. One of the things I remember being taught, and I think a lot of us were taught this, was that tool use was uniquely human. We were the only species that figured out how to make and use tools. That was a differentiator. That was what set us apart. Then we watched chimpanzees strip leaves off twigs to fish termites out of mounds. Then we watched crows bend wire into hooks to retrieve food from tubes. Then we watched octopuses carry coconut shells across the ocean floor to use as portable shelter. So tool use had to come off the list.
Language was also on that list of things that set humans apart. But then we did more research, and language had to come off the list too. Kanzi was a bonobo at a language research center in Des Moines, Iowa. Researchers gave him a keyboard of symbols. He didn’t just learn them. When they introduced kale, a food he had no symbol for, he described it as “slow lettuce” because it took him a while to chew it. He’d never seen that combination of words. He invented it. And whale songs. Humpback whales compose songs that change over time, that spread across ocean basins as other whales learn and adopt them. Whether that constitutes language in the way we mean it is still debated, but it’s not nothing. So language also came off the list of what makes us unique.
The list keeps getting shorter, and it will keep getting shorter. Our understanding of animal cognition, communication, and emotion is expanding faster than at any point in our history. Every few years, or more frequently, something we were certain was unique to humans turns out not to be. And that can make people uncomfortable. Because if animals use tools and communicate in ways we once thought were ours alone, what else were we wrong about?
So Gretchen Rubin’s current list of what makes us uniquely human includes some things you’d expect and some that are genuinely surprising. Humans are apparently the only animals to contemplate our own death abstractly, to feel complex shame, to ask open-ended questions to gain information, to shed emotional tears, to cook our food, to use symbols that stand for abstract concepts, to combine words in new ways to express unlimited new ideas, to contemplate the distant past and future, to blush from embarrassment, to do what she calls freighted walking, walking long distances while carrying things, and this one I did not see coming, to have chins. We are the only animals with chins. Researchers still aren’t entirely sure why.
So she’s not making a moral argument. She’s just observing differences, and that’s okay. What makes us different from other species is a genuinely interesting question. But what we do with that information is where it gets a lot more interesting. We’re not just cataloging differences the way a biologist might note that dolphins use sonar and we don’t. We’re building a hierarchy, and then we’re using that hierarchy to justify treating other species in ways we would never treat our own.
The list isn’t just descriptive. It’s what we use to justify treating them differently and often not giving their interests any real weight. And there’s a problem baked into the whole enterprise that we almost never talk about: we are the ones writing the test. Every item on that list measures other species against a human standard. We’re not asking what bonobos can do that we can’t. Or what elephants experience that we’re incapable of. We’re asking how close other animals come to being us. That framing makes human superiority the conclusion before the analysis even starts.
So let’s walk through a few items on Gretchen’s list, not to dismiss them, but to examine how solid those differences are. I’ll start with a few that I think probably hold up.
Chins. Sure, I’ll give us chins. Freighted walking is genuinely linked to human anatomy and our evolutionary history. The precision gripping thumb is real. So those abilities may very well be uniquely human. But now let’s look at some of the others.
Contemplate the distant past and future. Elephants appear to grieve based on memory of specific individuals. They return to their bones, not just any bones, their family members’ bones. They go quiet. They stand there. They touch the bones with their trunks, come back years later. That’s not instinct responding to a present stimulus. That’s memory of a specific individual carried forward in time after they’re gone.If that’s not contemplating the past, I’m not sure what we’d call it.
Complex shame. Well, honestly, what does that even mean? We see what we interpret as shame often with our dogs. And do we know enough about what’s happening inside an animal when it tucks its tail and averts its eyes to say with confidence that whatever they’re feeling isn’t complex enough to qualify?
What about contemplate their own death abstractly? Crows gather silently around their dead. They go quiet. They mob the area. They appear to investigate. Elephants return to the remains of their dead in ways that go well beyond practical behavior. Whether any of that constitutes abstract contemplation of mortality, we don’t know. And that’s the honest answer for a lot of the things on this list.
And then there’s something that’s not even on Gretchen’s list. Researchers found that rats would refuse to press a lever for food if pressing it meant another rat received an electric shock. They went hungry rather than cause pain to another animal. We have a word for that response in humans. We call it empathy. The rats weren’t just feeling something, they were responding to what another individual was feeling. That’s a capacity we didn’t think to put on the list because we probably just assumed it wasn’t there.
And notice what’s happening: contemplate death, but only if you do so abstractly; shame counts, but only if it’s complex; Every time an animal gets close to proving that it has one of these special qualities, we move the goalposts a little further out. But we put those goalposts there. We designed a test that measures everything against a human standard, and then we’re surprised when humans come out on top. What if a bird wrote the test? “I can fly and you can’t. Ergo, birds are clearly superior.” We’d call that absurd, but it’s the same logic.
I’m not asking anyone to have this all figured out. I’m not sure I do either. In fact, I’m sure I don’t. My opinions have always kept evolving. The question of whether different means inferior and gives us a license to treat other living beings as resources, to breed them and keep them confined, —to use them to test drugs and products—to cause them suffering? That’s not a biological question. It’s a moral one. And it’s why I changed the name of my class from Animal Law to Animal Law and Ethics. You can’t figure out what the law should be without thinking about this kind of ethical question. The law is supposed to reflect how we resolve moral questions like this. The list of differences between humans and other animals gets shorter all the time, and it will keep shrinking. It’s time we started examining our beliefs around this kind of hierarchical thinking and ensure that our actions and our laws are consistent with what we believe. Other species have their own right to be on this planet, and yes, to life, liberty, and the pursuit of happiness.
That’s it for today. The Animal Advocate is brought to you by the Animal Advocacy Academy. If today’s episode got you thinking about what you can do to change things for animals, I want to make sure you know about the Four C’s of Legislative Advocacy for Animals. It’s a free audio series I put together that gives you a real framework for making legislation happen. You can find it at animaladvocacyacademy.com/fourcs. That’s four Cs, F-O-U-R-C-S. And you can find all our episodes and show notes at animaladvocacyacademy.com. Subscribe so you don’t miss an episode. And if you know another animal advocate who should be listening, send this one their way! Questions on today’s topic or anything else? Just email us at podcast@animaladvocacyacademy.com. We’ll write back or we’ll feature your question in a future episode. Remember, compassion is great, but compassionate action is infinitely better. Until next week, live with compassion.
That’s it for today. The Animal Advocate podcast is brought to you by the Animal Advocacy Academy. You can find episodes and show notes at animaladvocacyacademy.com along with a link to our Facebook and LinkedIn pages where we discuss our podcasts and we’d love to discuss your thoughts and experiences there. If you’re interested in learning more about protecting animals, subscribe to the show so you get every episode when it comes out. If you have any questions on this or any other topic, related to animal law, email them to podcast@animaladvocacyacademy.com and we’ll make sure to get them answered. We’ll either email you back or feature them in a future episode, or both. And remember, compassion is great, but compassionate action is infinitely better. Until next week, Live With Compassion.`
