Short Wave - Mirror, Mirror, On The Wall: Can Animals Recognize Their Reflection At All?

Episode Date: August 13, 2021

(Encore episode) The mirror self-recognition test has been around for decades. Only a few species have what it takes to recognize themselves, while others learn to use mirrors as tools. NPR science correspondent Nell Greenfieldboyce talks us through mirror self-recognition and why Maddie's dog is staring at her. For more science reporting and stories, follow Nell on twitter @nell_sci_NPR. And, as always, email us at [e-mail]. See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

The dog days of summer are officially over, which brings us to our last episode of Shortwave's Dog Week. Today, a conversation I had last year with Nell Greenfield Boys about animals and mirrors, including my very own pup. Stay safe out there, y'all, and remember, make sure to give all your pets, all the cuddles, all the times. You're listening to Shortwave from NPR. Maddie Safai here with MPR science correspondent, Nell Greenfield Boyce. Hi, Nell. Hey, Maddie. So 2020 is almost over.

Thank goodness. Right. And we need to talk about something kind of disturbing that we have both experienced this year with my dog and your parakeet. Okay. I've told you again and again. It's not my parakeet. It belongs to the kids. Sure.

Sure. Sure. Sure. So since I've been working from home during the pandemic, I've spent a lot of time with my dog. Your dog is very cute. Yes, it keeps her alive. And one day, I noticed that she was watching me using the mirrors. Like, I'd wake up, look in the mirror, and I would see her little border collie face staring intensely, not at herself, but me in the mirror. Yeah, I mean, I was skeptical, but, you know, you've got the photos and it's striking. Yeah, it's startling, honestly. And I

know that your parakeet, sorry, your child's parakeet, is similarly mirror-obsessed. Yeah, that's actually kind of a known parakeet thing. It's not just, you know, our parakeet. They kind of zero in on mirrors. And, you know, it doesn't even have to be a mirror. Like my kid's parakeet doesn't even have a mirror. He's just, you know, whatever reflective surface, you know, like the side of a water dish or a bell or whatever. I mean, he just sits there and chatters away at it. Right. So, like, what I want to know is what does that bird think he's seeing? I mean, people use mirrors all the time, but what do animals know about mirrors? That is exactly what Gordon Gallup, wondered back in the 1960s. He actually was thinking about it one day when he was in his

bathroom. And it occurred to me, as I was shaving in front of the mirror, wouldn't it be interesting to see if other creatures, other animals, could recognize themselves in mirrors? These days, he's with the State University of New York at Albany. You know, back then he was a graduate student and he sat there shaving and he was thinking about it and he thought to himself, how would we know if the animal recognized itself in the mirror? Like, maybe you could see, put some bright red marks on its face. And then confront him with the mirror to see if it could use the mirror to then access and investigate these strange red marks. Yeah, I feel like I've heard of this idea or this test before.

Yeah, well, you probably have because this mark test is famous. It's been used by all kinds of people over the last half century to test lots of species to see if they recognize themselves in mirrors. And while science has learned a lot over the decades, there are. are still some huge disagreements here. So today in the show, we ask the question. Mirror, mirror, on the wall, what critters understand mirrors best of all? I'm Maddie Safaya, and this is Shortwave from NPR. Okay, now, so Gordon Gallup came up with this mark test, and I assume he actually, you know,

like tested some animals. The one that made the biggest splash was chimpanzees. So he put this big mirror just outside their cage, and at first the chimpanzees acted in the way that a lot of other species do. Like the mirror image was another animal, a stranger, you know, that you might attack. After a couple days, though, that changed. The chimpanzees started using the mirror

to look at parts of their bodies that they couldn't normally see. Like opening their mouth and looking at their teeth. They looked at their bottoms and their genitals. I mean, of course they did now. Of course they did. Then Gallup put the chimps under anesthesia and marked their ears and their foreheads

with a red dye. The animals woke up. They saw themselves in the mirror. And what they did was to reach up and touch and examine the marks on their faces that could only be seen in the mirror. So they realized the marks were on their own faces by looking in the mirror. Okay. So that's chimps, our close relatives. What about monkeys? So he told me that monkeys could be exposed to mirrors for literally years and would never spontaneously use the mirror. to do any kind of self-examination like that. But if somebody quietly snuck into their room and a mirror was there and the monkeys saw the person in the mirror, they'd turn around to confront them. They could use the image of us, me and my students, in the mirror to monitor our behavior

and respond appropriately. Okay, so just like my creepy little dog. That is just like your dog. I mean, I don't know if your dog responds appropriately to you. But yeah, I told him about your dog. and he totally thinks your dog could be using mirrors to spy on you. I mean, it sounds like her, no, honestly. But in terms of using a mirror like people do, to look at yourself, how many species can actually do that?

Well, if you ask him, he thinks it's just humans, chimps, and orangutans. That's his view. Okay, so you're saying if you ask him, that makes me feel like there are other views out there. Yeah. So if you ask Diana Reese at Hunter College, she'll tell you that dolphins and elephants can recognize themselves. And, you know, it is hard to test dolphins. I mean, think about it. They just don't have hands.

Right, right, right. You can't really, like, poke your own face with a flipper. Yeah, yeah. So she had to come up with variations of the mark test. Like, in one experiment, they used a marker to kind of draw on a dolphin's body in different places. But they didn't do it secretly. So these dolphins could actually feel the marks being made. The idea was, would they race to the mirror afterwards and orient immediately to the place?

where they've been marked, as if they had something in mind on their way to the mirror. They were going to use it as a tool to look at the mark. And that's exactly what we found. Wow, okay, that's pretty cool. What about elephants? They have trunks, right? So it feels like you could do this kind of mark test, maybe? Well, she and some colleagues did study elephants at the Bronx Zoo.

And so, again, not so easy. They had to get this big jumbo, eight-by-eight-eight-foot, unbreakable mirror. And she says the elephants seemed to look at themselves, and they did all kinds of unusual things. Like they'd rhythmically move their trunk up and down, or, you know, one of them would use a trunk to pull an ear forward in front of the mirror like it was looking at it. One of them touched this white X-shaped mark that they put on her head. You know, she used her own trunk to sort of investigate it.

But two of the others didn't do that with the mark. So, you know, Reese says she's tested other elephants since then, and she does think they get it. You know, she thinks they just recognize that what they see in the mirror is them. Okay, so back to the original Mark Test developer, Gallup doesn't buy that dolphins and elephants know themselves in a mirror. He just doesn't think it's been conclusively shown. I mean, there's been claims over the years about weird behavior with mirrors in all kinds of species. I mean, birds, fish, ants, even mantar rays.

And, you know, he says there's always this problem of if you have an animal doing strange stuff in front of a mirror, and they do do odd stuff, right? There's this danger of seeing whatever it is you want to see. You know, what their behavior actually means can be hard to figure out. Well, I mean, for that matter now, what does it mean if an animal unequivocally passes Gallup's marked test? Like, does that mean that they're actually self-aware? Gallup thinks that the test means they're self-aware.

He basically thinks that self-awareness is like being able to make yourself the object of your own attention. And he says that, you know, if you're looking at yourself in a mirror and recognizing yourself in the mirror, you're kind of like literally doing that. And that this says something about the animal's internal world and its ability to understand other animals' mental states. But, you know, that's a kind of romantic idea in a way, you know, that just this mirror recognition says something really profound about an animal's internal world. And so, you know, Daniel Povenelli doesn't really buy it. So he's a researcher, and he told me when he first read about Gallup's mark test for mirror self-recognition in high school, it made him want to spend his whole life studying chimpanzees. You know, I bought into the story of mirrors and self-recognition hook, hook, line, and sinker, because it is a compelling story. Yeah, I mean, like, wow, there are creatures out there just like him, just like people, and all it took was a mirror to uncover this magic secret about them or whatever.

Exactly. But I gather from his tone, he no longer feels that way. No, no. I mean, he's a researcher with the University of Louisiana at Lafayette, and he's spent years studying chimps and mirrors and self-recognition and all this stuff. And he says, you know, just think about when you go to a mirror. Say in the morning, when you wake up, you drag yourself there and you're looking at your image and like maybe you're all bedraggled with sleep in your eyes.

And you start having all of these thoughts, you know, you're just like, geez, I look older. And, you know, you think about time and time is passing. and then you start thinking about who you once were and your future and what other people think and on and on. But is that what's required? Do I have to think about any of that in order to brush my teeth in front of the mirror? He says you do not need all of these higher order concepts of a self and self-awareness to use a mirror in a practical way to just understand that like your physical motions are connected to the mirror in some way. Yeah.

So he's saying like when a chimp interacts with its own mirror image, we can't know what it's, thinking about. We have no clue. And Povinelli pointed out to me, with training in how mirrors work, Reese's monkeys can actually learn to recognize themselves in mirrors and pass the mark test. You know, so what does it mean if an animal with training can do this? He said he doesn't think a dolphin's been shown to do it yet, but he says, oh, it could probably be taught to do it, sure. What about my dog now? What do you think? I don't know. I mean, maybe. I mean, some people have suggested that for dogs, you know, the visual system isn't as important. and like self-awareness or self-recognition might be more like smell-related.

Yeah, yeah, that makes sense. So we need some kind of like olfactory mirror. Scientists have been working on that, Maddie. No doubt, no doubt. Okay, now, well, thank you for this tour through the mirror maze. That is research on animals and mirrors. I will think of you the next time I see my dog gazing at my reflection, which I imagine is going to be in like five minutes.

Enjoy. Enjoy it, friend. Today's episode was edited by Giselle Grayson, produced by Thomas Liu and fact-checked by Arielizabidi. The audio engineer for this episode was Josh Newell. I'm Maddie Safaya, and you're listening to Shortwave from NPR.