Psychologist Laurie Santos trains monkeys how to use money, and has learned that they attempt to solve the same sort of financial problems humans have attempted.

Lions love catnip.

They will roll around and lick and do all the things a house cat does when handed a toy filled with the psychedelic kitty-cat plant. Not all big cats are equally susceptible to the plant's chemical powers, and within a single species some respond more than others, including house cats. I bet it's a real bummer to learn your pet cat is immune to catnip, but that's genetics for you.

This cross-species sharing of behaviors among cats goes beyond tripping balls after huffing exotic spices. Big cats from the wilderness, like jaguars and tigers and leopards, exhibit many of the same behaviors you see every day in tiny cats who live in human apartments and backyards around the world. That cute little kneading of the paws? Yep. That weird face rubbing thing. Same. If you've been to a zoo and watched big cats at play, you've probably noticed many similarities there as well. They share a common ancestor a few million years back, and some things got passed down to both lines in their bodies and in their brains. They aren't identical though, natural selection tinkered with them separately and got different results, otherwise you'd see more people in the park walking pumas on leashes.

One of the most amazing things humans beings have figured out about the natural world is that all life on Earth is in the same family. If you had a magical photo album with the pictures of every one of your great grandparents, you would eventually flip over to pictures of fish. That's true for all animals. Bears and eagles and alligators with similar albums would all land on that same photographs after enough page flips. That means a lion and a sea urchin share a common ancestor. Of course, they don't seem all that similar on the surface. Sea urchins have never been all that popular in circus acts, and as far as I know, they have no special reaction to catnip. But they are related, deeply so, right down to shared genes and proteins and other bits and pieces. You can comfortably pet one and not the other because they've been evolving along separate paths for a very long time. Lions look and act a lot more like housecats than sea urchins because lions and tabbies share a more recent common ancestor.

Our guest in this episode of the You Are Not So Smart Podcast is psychologist Laurie Santos who heads the Comparative Cognition Laboratory at Yale University. In that lab, she and her colleagues are exploring the fact that when two species share a relative on the evolutionary family tree, not only do they share similar physical features, but they also share similar behaviors. Psychologists and other scientists have used animals to study humans for a very long time, but Santos and her colleagues have taken it a step further by choosing to focus on a closer relation, the capuchin monkey; that way they could investigate subtler, more complex aspects of human decision making – like cognitive biases.

One of her most fascinating lines of research has come from training monkeys how to use money. That by itself is worthy of a jaw drop or two. Yes, monkeys can be taught how to trade tokens for food, and for years, Santos has observed capuchin monkeys attempting to solve the same sort of financial problems humans have attempted prior experiments, and what Santos and others have discovered is pretty amazing. Monkeys and humans seem to be prone to the same biases, and when it comes to money, they make the same kinds of mistakes.

Santos and her colleagues created something they call the monkey marketplace, an enclosure where those monkeys could comparison shop with their tokens. Inside, human merchants offered deals for grapes and apples, some better than others, some risky and some safe, and the tiny primates picked up on these factors, changing their behavior in exactly the same way as humans. In fact, Santos says that on paper, across many experiments, you can't tell capuchins and humans apart.

In the interview you'll learn how her research has led Santos and her team to suspect that many of our problem-solving behaviors are innate, passed down from a primate ancestor, and not wholly learned via culture or institutions. For some of the dumb things humans do, it seems we aren't observing human irrationality, but primate irrationality. You'll hear how this knowledge is important when it comes to building a better world and solving the problems that arise when we use those old primate strategies in new human institutions. You'll also learn from journalist Daniel Luzer how lobster became fancy. Later in the show, we learn where science says you should sit in a high-school classroom if you want to become popular on campus.

Episode shownotes and subscription information

Image: Shutterstock