Apes exhibit years-long memory for the faces of former groupmates. A biological anthropologist and comparative psychologist discuss long-term memory in great apes and the evidence for complex social memory across the animal kingdom. Listen with the above player.
Dr. Laura Lewis and Dr. Chris Krupenye have been exploring long-term memory for members of the same species and for others, in chimpanzees and bonobos. In this episode of Many Minds, the two discuss how their research team used non-invasive eye-tracking to tell whether the apes were looking longer at images of their previous groupmates or images of strangers, and what about the animals' social relationships seems to shape their social memory.
Many Minds podcast host, cognitive scientist, and writer Kensy Cooperrider introduces the episode:
"If you want to have a rich social life, you're going to need to know who's who. You'll need to distinguish friend from foe, sister from stranger. And you're going to need to hold those distinctions in your head — for at least a little while. This is true not just for humans but — we have to assume — for other social species as well. But which species? And for how long can other creatures hold on to these kinds of social memories?
My guests today are Dr. Laura Lewis and Dr. Chris Krupenye. Laura is a biological anthropologist and postdoctoral scholar at UC Berkeley; Chris is a comparative psychologist and an Assistant Professor at Johns Hopkins. Along with a larger team, Laura and Chris recently authored a paper on memory for familiar faces in chimpanzees and bonobos. In it, they show that our closest cousins remember their groupmates for decades.
Here, we chat about the paper and the backstory behind it. We consider the anecdotes about long-term memory in great apes — and how Laura and Chris decided to go beyond those anecdotes. We talk about the evidence for complex social memory across the animal kingdom. We discuss the use of eye-tracking with primates and its advantages over earlier methods. We also talk about why long-term social memory might have evolved. Along the way, we touch on dolphins, ravens, and lemurs; voices, gaits, and names; the different gradations of recognition; and how memory serves as a critical foundation for social life more generally."
Play the episode with the above player.
You'll hear:
- How chimpanzees and bonobos both looked significantly longer at images of previous groupmates that they hadn’t seen for years. In one case — for 26 years.
- What the evolution of social cognition in the animal kingdom might teach us about ourselves. "I’m really interested in how we form, build, and maintain social relationships – how we, as humans, do that, and how other great apes do that. Social relationships are so vital for our survival and wellbeing," says Lewis. "They’re fascinating, and some of them are stable over time. Some of them are not so stable over time. We can have friendships that last decades, and then they shift, and in old age, we have less friends, but we’re closer to them. I’m really curious about the psychology behind all of that and how that’s evolved."
- Why it's so vital to study great apes. "Our hope here is that showcasing how clever and interesting and similar to us they are will engender interest in their conservation," Krupenye shares. "I think, even just selfishly, we have to save these species if we want to continue to better understand ourselves. There’s also a strong case to be made that great apes deserve to exist in their own right."
Be sure to check out the show notes for links with detailed information.
Learn more about Templeton World Charity Foundation's Diverse Intelligences priority.
Templeton World Charity Foundation's Diverse Intelligences is a multiyear, global effort to understand a world alive with brilliance in many forms. Its mission is to promote open-minded, forward-looking inquiry in animal, human, and machine intelligences. We collaborate with leading experts and emerging scholars from around the globe, developing high-caliber projects that advance our comprehension of the constellation of intelligences.
Many Minds is a project of the Diverse Intelligences Summer Institute (DISI), made possible through a grant from TWCF to the University of California, Los Angeles (UCLA). The Many Minds podcast is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte. Creative support is provided by DISI Directors Erica Cartmill and Jacob Foster. Artwork featured as the podcast badge is by Ben Oldroyd.
