The Dolphin in the Mirror – Podcast Transcript

DIANA REISS (COGNITIVE PSYCHOLOGIST AND MARINE MAMMAL SCIENTIST, HUNTER COLLEGE): So I wish I could take you all with me to meet a dolphin face-to-face or flipper to flipper. They are remarkable animals, I'm extremely honored to have been had so much time to work with them. But I'm going to do my best to give you a sense of some of the experiences and things I've learned working with these remarkable animals. So this is a bottlenose dolphin, and I happen to love this image because I feel like there's someone in here. And I use the word “someone”, it's not a person, but there is a level of consciousness here that really rivals, I think, the consciousness that we have. They don't do everything we do, they're not humans, but these are cultural, highly evolved creatures. And I often say that these bottlenose dolphins–the Latin name is Tursiops truncatus–are my research collaborators. I say that because I try to watch them, and I try to glean from them ideas about what would work, what kinds of studies might we do to able to really explore the nature of their intelligence, the nature of their communication, and I get my ideas from them. I try to sort of stay out of it as much as I can and give them apparatuses that they can interact with, so we can observe.

We do both experiments and observational work, and I'm going to share some of those research projects with you tonight. I try to find approaches that give us what I call these glimpses of dolphin intelligence, and insights into their behavior. Now, many of my colleagues work in the field, as we do as well. We have field sites in both Belize and Bimini–that's when my friends say, gee, that's too bad that you have to force yourself out to those places and study them. But it's that marriage of work that we do in the field and in aquaria that gives us the richest possible ideas about what's going on. Not any one of those gives us the whole picture clearly, and we're far from understanding the whole picture. But what you can learn when you work up close and personal with dolphins in aquaria, how you can sort of plumb the depths of their mind, is quite different than what we see in the field. What we see in the field in terms of foraging strategies, group dynamics, are quite different than what we're going to observe in aquaria, so it's that combination of approaches.

I just want to give you one little piece of information from something we're doing right now. I won't be able to talk much about the field research tonight, I'm going to focus on what we've done working with dolphins in aquaria. But one thing I'm very excited about is my colleagues at Rockefeller University and my colleagues in my lab, the students in my lab, have been working with these aerial drones you've been hearing a lot about. And we're trying to be as invisible as possible to watch the social behavior of dolphins. So when we're working with them in aquaria, when we're in boats on the surface of the water, they know we're there, they're interacting with us. But how do you become invisible, as much as possible, so we can really observe them?

So here's some images we're getting from the use of drones, it’s kind of like being disembodied and flying over them. They don't seem to attend at all to the drones, just a few times have we seen dolphins actually look up. We can hear this remarkable variety of acoustic signals they use. They use acoustic signals, whistles, clicks. You're hearing those echolocation clicks, these buzzes are part of the echolocation, where they send out broad beams of sound, get reflected signals back, and they can navigate in their world. They can get information about objects in their world. So we're starting to be able to study the social dynamics, as well as listening to the sounds. We don't have hydrophones, underwater microphones, on the drones, but we can have them placed in the water remotely or off of boats that are at a distance. So I just wanted to share some of that with you.

And again, as I said before, what I'm going to do tonight is I'm going to focus on a couple of the experimental approaches that we've used to study the nature of communication with dolphins. I'm going to talk about our use with mirrors to investigate aspects of self-awareness, and I'm going to talk about some interactive systems that we did quite a while ago with an underwater keyboard, and then more recent work I'm doing with my colleagues at Rockefeller University, where we created a much more modern and sophisticated technology: an underwater touchscreen.

So first I want to get us all on the same page about these dolphins. Dolphins are cetaceans. And there are two sub-orders of cetaceans: there are the odontocetes, which are the toothed whales and dolphins. So killer whales are odontocetes, pilot whales and beluga whales are odontocetes, bottlenose dolphins that we're talking about are odontocetes. There are about 73 species of odontocetes.

And then there are the mysticetes, the baleen whales. These are the really large whales. They don't have teeth, they have baleen plates, and they can scoop up huge amounts of water. They can do what's called filter feeding, and then they grab a lot of water in their mouths they squeeze the water out and krill and other small organisms and small fish get stuck on the baleen. So this allows them to ingest a great deal of prey.

So dolphins are complex in many ways. First of all, they have large and complex brains. So our brains, our human brains, weigh about 1,300 grams, where the bottlenose dolphin brain weighs about 1,700 grams. I want you to notice that these brains have a lot of folding. You see all these folds these are these are and this is gyrification. And their brains are complex in ways that ours are complex, but they're also very different. Now, their brains weigh more than our brains, but their bodies way more than our bodies. So the dolphin brain is second only to the modern human brain in measures of relative size. So relative to their body, they're the second largest brain on the planet.

We call this an encephalization quotient, or EQ. That's this ratio between brain size and body size. Our brains are seven. Seven times the size that it takes to run our bodies, the human body. The encephalization quotient is number seven for humans. Our closest relatives, the great apes– the chimpanzees, orangutans, gorillas–range from about 2.3 to 1.8 times the size to run their bodies. Dolphins are 4.2, second largest brain to humans in terms of relative brain size. But dolphin brains and human brains evolved to be large and complex in different ways. I'm not going to have time tonight to go into all those different ways, and I don't study the cytoarchitecture of the dolphin brain. I'm not a neuroscientist specifically, where I study the brain, but my colleagues have studied the brains of dolphins over the years, and I'm going to give you an example of one way that they're different.

The cetacean neocortex, the outer covering, is thinner than the human neocortex, but it has much more surface area than our brain. It has what we call more gyrification, what I just talked about. Gyrification is the folding of the cerebral cortex. And they have more gyrification than any other mammal on the planet, including humans. Bottlenose dolphins and another cetacean species, the pilot whale, have higher levels of gyrification. So there's a lot of surface area packed into that braincase. The other thing that we don't know much about is whether the size of the neuronal body, the cells, are important. And dolphins and elephants, for example, have bigger neurons. But they're less densely packed in the brain than we find in human brains and other brains. But it's not clear what that means. So we still have a lot of information to understand about what equates with intelligence, what's this magic recipe for an intelligent brain?

So far what we think is that these larger brains tend to equate with more complex behavior. And the larger EQ's also tend to equate with more complex behavior. So here we have this large, complex, beautiful brain. What is it doing? And that's what my world is about, to try to ask the question what are they doing with this brain? And I'm trying to find ways of not being too focused on what us humans do, but it's a good starting point in some ways, to say are they capable of certain things that we're capable of? And then, how can we open it up to let them show us their best stuff, what they can do with the system, if we give them control? So let me start first by telling you a little bit more in general about dolphins, so we'll be on the same page.

Dolphins live in complex societies in the seas. And they show both social and behavioral complexity. They live in what we call fusion-fission type social structures. So do we, so do the great apes, so do dogs, and a few other species. Fission-fusion means that they come together with other individuals, and then they break apart. So they have a lot of alliances, a lot of buddies, and they maintain those long-term relationships. But then they can make other alliances. They can even form what we call second-order alliances. So they have alliances that form with other alliances into what we call second-order alliances. And dolphins do even more than we find in chimp societies, they form third-order alliances. This is work that's been done by one of my colleagues, Dr. Connor, and that's more that's more complex than we even see in any ape society.

So they have these long lasting relationships, they show highly cooperative behavior. For example, dolphins in the wild and in aquaria have been observed to do what we call “auntying” behavior, where you'll have a few females watching large groups of infants, or calves of different ages. Or you'll have one mom babysitting, or “auntying” her own calf and another's calf while that mom takes it easy or goes off and does other things like foraging. We've observed this in our own lab, and it's been seen in the wild. There's also cooperative mating between males in certain parts of the world. It's not the same all over, these animals develop cultural patterns that vary from group to group. They also show empathy, or caregiving, or help behavior. There are ancient myths about dolphins saving sailors. There's an ancient Greek myth about Aryan, who was a lute player, very wealthy, being thrown overboard by pirates who wanted to grab his money. And this ancient Greek myth from the 4th century reports that Aryan was rescued by a dolphin, who took him back to Corinth where he was heading, and this dolphin was more was immortalized in coins showing Aryan on a dolphin. And it's one of these ancient myths.

However, we have lots of newspaper stories and accounts of dolphins doing it today. I hear these stories, people call me with them, I collect articles about very similar kinds of behavior. Do they know what they're doing? What evidence do we have that it's not just a hardwired response of a mammal that breaths air. Dolphins are mammals, they have to breathe air. Maybe it's an adaptive mechanism so that anything that's flailing at the surface they would push to the surface. Again, it could be adaptive, but I don't believe it is. I don't think most of my colleagues believe it is. Because they don't always do it, and it's quite flexible, and it's done in different context, and done differently in an appropriate context. We've watched dolphins push other animals up, push humans up. They've often pushed animals down and away, in a case where a dolphin was flailing at the surface after being harpooned, and some pilot whales held up an alliance member at the surface, and then pushed it away from the boat. So we don't think it's hardwired.

They also show many cognitive abilities that are found in the great ape species. Now dolphins are non-handed, but they're manipulative, and they're creative. So dolphins will often be seen in the wild carrying bits of seaweed, using sponges. My colleagues Janet Mann and her students at Georgetown have reported dolphins using sponges to forage in Australia. In areas where they have very rough sandy bottoms, they'll take these marine sponges, and it would seems to protect their rostrums as they're digging in the sand. Yet, when they are foraging in nearby areas where the sand is much softer, they don't use sponges. And only certain animals use them, and that seems to pass through the group. There's evidence for cultural learning in dolphins from that study and several others.

So, dolphins are vocal learners. And what's interesting about that is that we are vocal learners. And there's only a handful of other species that are considered vocal learners, where they actually learn their vocal signals. Some animals modify the signals, but to learn them you actually have to hear new signals and then imitate them. So humans are vocal learners, avian species, bats, we have evidence for pinnipeds, or seals and sea lions, elephants, and cetaceans: dolphins and whales. And we did some studies at our lab, I'm not going to have time to talk about this tonight, but some of my earlier work looked at the vocal development or what we call vocal ontogeny of whistles in young dolphins. We had several animals born in our lab, and we saw that they babble, they play with sounds. In the beginning, they have a much larger repertoire than the adults do. It's what babies do, what birds do, and then through their interactions with their moms and others in their group, they start using just the signals that the others are using. And they have their own individual signal that we call a signature whistle, or a contact call, as well. We don't quite understand what that means completely, but it seems to carry an identity and perhaps more.

[FIELD RECORDING OF DOLPHIN SOUNDS BEGINS TO PLAY]

These are recordings from the field, this is in Bimini where we study both bottlenose and spotted dolphins. I just want to give you a sense of the interactions, the sounds. These are highly fluid groups, and it's really a challenge to be able to localize who's whistling and to really be able to understand how they use their communication signals. We have to be able to localize the source of the sound, this is something that my colleagues and I are trying to do right now. It's really created a problem when we try to decode. And one of the things I've been trying for years is to decode dolphin communication. They produce whistles and clicks and squawks and all sorts of signals that I’ve been playing for you, but so far we haven't been able to decode how are they using these. Are they referring to things in their environment? Are they using them in any way that's similar to what we humans do? We simply don't know. But what's interesting is the dolphins, beyond being vocally mimetic–they learn signals, they imitate vocal signals, that's how they learn them–they're behaviorally mimetic. And when I first got started, when I was a young student, there were lots of reports of dolphins imitating the behavior that they saw people do. 

So one of the earliest stories I heard was a diver was in a pool in an aquarium, scraping the sides of the windows clean with a with a scraper, wearing a SCUBA tank, and the dolphin came up next to him, got a piece of broken tile off the bottom of the pool, and started scraping next to the diver and emitting a bubble stream out of its blowhole, sort of imitating the behavior of the diver. I'm going to I'm going to tell you one last story here, and then I'm going to dive into some of our work. This is what really inspired me the most. This is me with a really bad perm, I don't know what I was thinking there. But I when I was a graduate student, I had the opportunity to have a grant from the French government, I was doing my studies at Temple University in Philadelphia, and I was working with the dolphin in France that I named Circe. and I was asked in this little French lab to, in exchange for me working with her, to teach her to station.

She was a dolphin who had just been taken from the wild, we shouldn't be taking dolphins from the wild, we used to do that and from what we know now, we really shouldn't do it. They need to be left where they are. Most aquariums no longer do it in the United States. They're still taken from the wild, unfortunately, in Japan, China, and several other countries. We're trying to bring an end to that, but at that time, people were doing it, and this dolphin was four years old and I had to teach her to station, which means stop in front of me and eat fish when I hold the bucket on the side of the pool. I was asked to do this, and what I was given were these big mackerel, these big Spanish mackerel. And the dolphin’s head was only about this big, so I decided to cut it up into heads, middles, and tails. And Circe would eat the heads, she would eat the middles, and she spit out every tail. So I started to cut off the little sharp fins and the tail fluke, and she immediately ate them. In the course of me working with Circe, she didn't know to stop. And if she was with me, and left the area where I was standing, I would give her a timeout. And what that looked like was, I would simply back away from the pool for maybe 15 to 20 seconds, and she would just watch me. And it was breaking our social interaction, and breaking the ability to get more fish. I used it as a correction mechanism.

Everything was going fine. Circe learned to stay stationed when I gave her the signal and to eat fish at the station, and one day by accident I happened to throw her an uncut tail. It was my mistake. She looked at me, she sort of gave me this eye, and she spit the fish out, and made a beeline across the pool and took a vertical position and looked at me and stayed there. Yup. And I said, is this possible? Is she actually giving me a timeout? Now that's an anecdote, and I had no idea what to do with that. I certainly couldn't report it in any way, but I made an experiment out of it. And this is what I mean that she was my collaborator, she gave me this idea. So what I did was, I purposely fed her really carefully, cutting every tail over the next couple of sessions. She never did it again. And then about a week later I gave her an uncut cut tail. What do you think? Boom, right across the pool. Again, took this vertical position. The two other times I did it, she did the same response. She only did it when I gave her uncut tails. Was she really giving me a timeout? This wound up to be a chapter in my doctoral thesis–it's the one my committee like the best actually because I was looking at visual discrimination abilities in these animals. But it was probably the most compelling chapter and the one that was unplanned until I began working with the dolphin. And at this point I realized this was a brain, or a mind, to contend with. This was a remarkable mind. So what kind of experiments can we do to get glimpses or reflections on the nature of their intelligence? I'm going to tell you about some of the experiments we've done in my lab, some in the past and some new experiments we’re doing right now.

So we know, when we see our face in the mirror, that's us. Mirror self-recognition, often referred to as MSR is one index of self-awareness. We can be aware of our self in so many different ways, we have to be aware of our bodies in space or we'd be bumping into each other and into walls, but mirror self-recognition is one index of self-awareness. And we used to think it was uniquely human. Self-awareness is not a unitary ability, again, it's one measure. So mirrors are wonderful tools to look at these abilities in humans and other animals, and when they begin. We can look at this developmentally, we can say which animals share with us this ability for mirror self-recognition. So let's unpack this a little and think about the cognitive abilities that we need for mirror self-recognition. To be able to recognize one's self in a mirror, you have to pay selective attention to what's in the mirror. A lot of animals simply don't attend. There's a mirror in the environment, they go right past it. So we did studies at the Central Park Zoo here in New York showing a mirror to harbor seals, and they paid no attention. Many animals pay very little attention. My cat, who's quite smart, and my dog, that's quite smart, never get it. They don't even pay attention to what they're seeing in the mirror. They may see me in the mirror, but they don't pay attention to their own image.

Once you pay attention, and again, only a handful of animals do that, how do you interpret that information? Do you see it as yourself, or do you think it's another of your own species? So the interpretation of that information, how do you process, that is critical. And finally, it requires not just the mental capacity for information processing, but the motivation. Because if an animal understood it was looking at itself but simply didn't care and just walked away, we wouldn't have any behavior to study. So some animals may know it's themselves, but don't care and move away. We can't look at what's inside the mind of an animal. But what a mirror does, it allows us to see behavior and reflections of the cognitive abilities of animals. So when in our own species, babies start showing mirror self-recognition between 18 and 24 months of age. And developmental studies of humans have shown that mirror self-recognition emerges with more social awareness. When sensory motor development is more advanced. Before that, kids don't show it. So children seem to have to have a sense of proprioception, that means they can track their movements in space. Because if they're going to notice themselves in a mirror, and understand there's a one-to-one relationship between their own behavior and what they're seeing in a mirror, they have to understand how they're moving. We have to have proprioception and advanced sensory-motor development and be aware of others versus self. So young children, when they're starting to show mirror self-recognition, also are able to do what we call synchronic imitation. They can imitate what someone else is doing.

What about mirror self-recognition and other animals? How do we ask the questions about these other minds? So mirror self-recognition was a rare ability, as I said, that was thought to be uniquely human. And then it was shown in great apes. All the great apes, from the common chimpanzee to the bonobo, to the orangutan, to the gorilla, show it. Gordon Gallup wrote a seminal paper in 1970 Science Magazine showing that the chimpanzees were the first to show it other than humans. What's interesting is that of the primate species, only the humans and apes show it. There's sort of a cognitive gap, it seems, where Gibbons, old-world monkeys, and New World monkeys, no matter how much they're exposed to mirrors, do not spontaneously show mirror self-recognition. Some recent studies have trained some of the monkey species like rhesus macaques to attend to the mirror and to show some behavior that looks like they understand, but this is with a great deal of training. Only the humans and great apes seem to show it spontaneously, and I think that is a significant difference.

So what's the basic approach that's used? You show a human or a chimp a mirror, they show three stages of behavior. First, you see exploratory or social behavior. They may try to look behind the mirror, over the mirror, see if there's somebody there, touching the mirror surface. The second stage that emerges is what we call contingency testing. This is the stage where you see the one-to-one relationship between yourself, your own behavior, and that of the image in the mirror. And this is the precursor to the next stage, which is called self-directed behavior, where the mirror is used to view yourself. You know it's yourself. Humans or other animals may look in their mouths, look in their eyes, look at their genitals, do all sorts of unusual behaviors. They're using the mirror as a tool to view themselves. And again, there’s only a handful of animals we've seen do this. Self-directed behavior in and of itself is considered evidence of mirror self-recognition, but there's one further test that Gordon Gallup–again, who did the first study with chimps–devised called the mark test. This mark test is where a mark is put on a human or a non-human animal, and it's a mark that is non-tactile. And the idea is that when the subject gets in front of the mirror, they touch the mark on themselves, not the mirror. And they touch the mark on themselves more so after they've been at a mirror than before they've been at a mirror, suggesting that they understand that it is themselves. This is one further test, and what's considered sort of another test of mirror self-recognition.