How Smart is an Octopus?

Hey, please take a second and leave us a review on Apple Podcasts, Spotify, or wherever you listen to the podcast. Thanks a lot. Hey, Welcome to Science Stuff, a production of iHeartRadio. I'm Hoorheit cham and today we're asking the question how smart is an octopus? We've all seen the videos online of octopuses appearing to do amazing things and be curious and clever, but it is there real intelligence

Hey?

Everyone, Today we're talking to three experts. First is a scientist who's been studying octopuses for fifty years, Professor Jennifer Mather.

I'm recently retired professor in the Department of Psychology, University of Lethbridge.

What is your background studying octopuses.

Well fifty years. As a kid, I grew up at the edge of the ocean and taught the animals were wonderful and fascinating and decided I was going to study them when I grew up.

What made you so obsessed with octopuses?

They're fascinating and wonderful. I love watching the weaving move and I love watching the patterns that they show on their skin, and I love trying to figure out what they're doing with all those.

Arms because it's so different from us.

Yes, they're not aliens, they're just different.

The second expert is doctor Alex Schnell, the National Geographic Explorer.

I am a comparative animal psychologist, and that is just a fancy word for saying I study animal minds, and the particular group of animals that I mainly study are

You sort of run the same tests that people have done on those animals, on cuttlefish and octopuses. Yeah, and finally, our last expert is doctor Tamar Gudnik.

I am a researcher no esologists studying sophalo pods of various types for the past almost twenty years now. Then my main research animal has been octopus.

Amazing. What does neuroethnologist mean?

It is the connection between study of behavior and neuroscience, So how the brain creates behavior?

All right? The first thing I wanted to ask our experts was how did octopuses evolve? I mean, they're so different from us. Where did they come from?

So? Cephalopods appeared over five hundred million years ago, and originally their ancestors had shells like the nautilus'es, and then many of the lineages moved into deep water where they gradually lost their shells. Really that meant that they tradeed defense for mobility and flexibility because they're able to be a bit more agile.

Now, okay, So cephalopods, which include octopuses, cuttlefish, and squids, branched the evolutionary tree of life about five hundred million years ago. This was a long time ago, and they started off as squishy animals with shells, kind of like the nautilus that then ventured out to the deep sea where they lost their shell. Why did they lose their shell? Why weren't shells useful down there?

Well, we think that potentially in the darkness, you might not need a shell to protect yourself, and so it really was a trade off. Now they're completely soft bodied, but now they've got more mobility and more flexibility to move around, I.

See, and you don't have to carry around a giant.

Shell totally no baggage.

All right. So in the deep, dark, open ocean, there weren't as many animals trying to eat them, so they devolved their shell. But then eventually some of these squishy pre octopuses moved back to shallow waters. There things got dangerous, you know.

We see think that they probably faced intense predator pressures compared to many other animals because they have no teeth, no claws, no antlers, no shell, nothing to protect themselves, and so they really had to use their ability to blend in like their camouflage or their brains to kind of one up all the things in the ocean that might want to eat them.

Interesting, there were boneless filets. Basically, yes, exactly skinless boneless was it perfect snack?

And the idea is that they evolved in a sort of an arrange race with bony fish. There were prey and predator for each other. And with the speed and a predatory lifestyle, there was also an increase in intelligence or cognitive ability.

And so the pressure was on them to be smarter in this environment of competition.

Well, I mean, the more you move, the more of nervous system you need.

So the history of octopuses is that they were not lost their shells, but when they came back to shallower waters, suddenly they were very exposed. And so to survive they had to get smarter, and that meant upgrading their brains. So the next thing I asked their experts to do was to describe and octopus's brain. What can you tell us about the neurology of octopuses.

By the definition we use for brain size, which is brain body ratio, they have a fairly big brain, bigger than a pigeon, bigger than a laborate.

I see, yes, relative to their size, octopuses are as the kids say, big brain and This is interesting. That brain is in the shape of a donut.

So, yeah, cephalopods have really unusual and highly specialized brains. So their central brain forms like a donut shape that wraps around their throat. And so they're esophagus what so all the food that they ate passes through their brain.

What do they have a donut brain?

Yeah?

Fascinating.

It also has a limiting size in terms of what you can eat because the esophagus goes through the brain.

It limits the size of things they can eat because it has to pass through the brain. So they really think through their food literally. Yeah. The other unique thing about octopuses is that they have a lot of neurons and most of those neurons are not in their central brain. How many neurons or green cells do octopuses have?

So there are two things. One is how many nerve cells do they have? That is around five hundred mealsman, But about more than half of that is actually outside the brain, so it's outside the central nervous system.

But the interesting thing about it is three fifths of their neurons are not in that brain. They are out in the arms. Each arm has a dorsal nerve cord which is actually a chain of ganglia all the way down they are.

Yes, more than half of an octopus's neurons are in their arms nerve structures called ganglia, So their arms are sort of independent, each process what they feel, its sense, and a lot of how each arm moves. But as our experts say, that does not mean they have nine brains.

Now. It doesn't mean that they have eight mini brains, as some media reports suggests, because complex decision making still requires communication between the arm clusters and the central brain.

So it's not like each arm thinks for itself. But their whole nervous system is definitely different than ours. It's more spread out, And this is interesting because it's another way of putting together a brain.

What I find so fascinating is despite having such different neuro architecture, pods are still capable of intelligent traits and the glimmers of intelligence that we're seeing in humans, chimpanzees, cars, dolphins.

Yeah, I mean they diverged five hundred million years ago.

Yeah, we're seeing traits that are really familiar to us when we think about intelligence.

All Right, when we come back, we'll talk about what those traits are meaning, what can octopuses actually do. How smart are they exactly? And then later we'll tackle a big mystery about octopuses that has puzzled scientists for decades. To stay with us, we'll be right back. Welcome back. We're talking about how smart octopus is sin thephalopods in general are. And so far we've learned how octopuses evolved and how that pushed their brain to be smarter. But

We're talking in about an animal with a nervous system out of a completely different evolutionary life. This brain is just in no way related to what our brain looks like, what a mouse's brain looks like, what a lizard brain looks like, it's just completely different in terms of how it's organized. You have about three hundred million neurons in the octopus that are outside the central nervousness. So if you look at an octopus arm, octopus arms have hundreds

They have photoreceptors in their suckers, so they can see with their tentacles.

Well, I mean they don't have lenses. I think, so an octopus arm will respond to a change in lighting without the animal itself being able to see the change in lighting.

So their whole nervous system is more spread out in some way. They sort of think with their whole body, not just their brain and stomach like some of us. Okay, so what can this totally different, almost alien nervous system of the octopus do? How smart is it? I asked each of our experts to tell us what octopuses are known to be able to do, and the first thing they pointed out was that they're really good at navigating.

So in terms of their cognition, I mean, we know that they demonstrate really advance learning and memory, and they have exceptional spatial navigation abilities.

And remember where they were. They can remember how to get back home, for instance, and then just imagine that they're going out hunting, so they can go out, hunt, come back, and then the next day they can say, okay, I went out that way yesterday, there's not going to be any food there. I should go out in another direction. So they're not just remembering where everything is, they're also remembering where they have been.

And this, the experts say, demonstrates a very important sign of intelligence called episodic memory, which means you can remember what, when, and where something happened. For example, octopuses and cuttlefish can remember what they ate, where they ate it, and when. If you set an experiment where say you vary the kinds of food you put at different times in different boxes around where they live. In other words, they can

Yeah, the footpods in general expert problem solvers, and some octopuses can even use tools. So the coconut octopus transports coconuts and other objects as portable shelter, and so it lives in a very barren type of habitat in Indonesia called Limbay Strait, where it's just black volcanic sand. There's

Oh, they get inside, and then they pull the two house together. Whoa, they created their own little house. They're basically building a house their own arvy. Yeah, so that's tool use. You would count that as tool use.

Yeah, it's tool use because they're using an external object for a very directed goal and they're manipulating that object.

Yeah, if you search for coconut octopus, you see videos of this octopus carrying around coconut shells and then hiding in them if they're in danger. Another example of how smart they are is that octopuses have been seen to play.

They play interestingly enough.

What do you mean?

We set up this experiment out of the aquarium, So we had an octopus in a tank that had practically nothing in it. So we gave the octopus a floating pill bottle and it floated up above the animal and the water pushed it towards it, and the octopus aimed a jet of water and set it to the far end, and it came back wow, And the animal was doing the equivalent of boutsing the ball. There were two individuals who did this in one I think was eight times and another one was twelve times.

Basically, the idea of play is that you have an object that there is no purpose in it interacting with it. There's no food involved, there's no reward involved. It's not going to give you anything, and still they keep taking the object, taking it close, throwing away, keep doing it, throwing it away, and so that is quanta viable of saying there is a form of play there.

Yeah, octopuses like to play. And there are lots of other examples of observations of octopuses seeming to solve problems and show flexible thinking. But one of the problems is that a lot of these observations are anecdotal, meaning that people have reported seeing octopuses do these things, but very few of them have been tested in a scientific experiment. And that's because octopuses are known to be terrible experimental animals.

Did so in humans, what the experiments would do is they would tell the child, here's a marshmallow. You can eat this marshmallow straight away, but if you wait fifteen minutes, you can have a second marshmallow. And then they'd leave the room and they'd see what the children would do. And this is a really difficult task. I mean, it's very tempting, especially if you like marshmallows.

It would be tough for me for sure.

Okay.

This is famously called the Stanford marshmallow experiment, named after an experiment done in the nineteen sixties by psychologist Walter Mitchel at Well, Stanford, and the essentially boils down to offering a subject the choice of getting a treat now or waiting some time to get a better treat. Leader Basically, do you have self control and can you think about different possible futures and trade off what feels good now

So in rats and pigeons, they're willing to wait a few seconds and then they kind of give in, whereas in your larger brain, vertebrates like crows and chimpanzees, they wait up to two, three, four minutes.

So then doctor Schnell wondered, what if you do this experiment with a cephalopart.

And so I decided to adapt it, and I swapped out the marshmallows for different types of shrimp because a marshmallow would not be tempting for a cuttlefish.

Did you try shrimp marshmallows?

I hold my should off. So essentially I created two different clear treat boxes. They learned that one the door would open straight away and the other one the door would only open after a delay. And the really neat thing about it is they showed similar coping mechanisms to what you see in children to kind of cope with the temptation of that treat. So they'd turn their body away and not look at the treat, which you see in a lot of kids, kind of closing their eyes.

And that's incredible. Did they cry for mommy also or not?

Quite?

So if they opened one box, they couldn't open the other. I guess somehow the animal knew that they had to choose.

That's right. So I expected the cuttlefish to wait a few seconds, and I was blown away because there was differences amongst individuals. But my most patient subject write it for two and a half minutes.

Wow, and that must be ages for a cuttlefish. So yeah, cuttlefish are as strategic or as patient as perhaps a chimpanzee or a five year old kid. Okay, So now the question is what does this all mean to any of these examples? Tell us just how smart an octopus is? Is it smarter than a cat or a monkey or an elephant. When we come back, we'll tackle that question and we'll get to one of the biggest mysteries about octopus intelligence that still puzzle scientists today. So stay with us,

Another thing that we see is intraspecies cooperation. So there are some studies that show that octopuses work together with certain types of fish, and that's something that we've heard for ages from divers and fishermen, and now we have more systematic observations of that happening.

What do you mean they work with fish.

So there's a lot of species that actually cooperate. You have one animal that protects and the other animal that hunts. There are all kinds of cooperations, and we're not completely sure what each one of them contributes exactly to the cooperation. Which one is the protection, which one is the hunting.

You're not sure which one drives the getaway car.

Yes, we're not sure which one's driving the getaway car, and which one's responsible for cleaning after. It's very new and it's very interesting.

Now. The thing about working with other animals is that lots of species do it. A lot of animals, including insects and even shrimp, have symbiotic relationships with other animals. But that doesn't mean they're necessarily smart. It could just be instincts they're born with. But in octopuses, doctor Goodnik says that's not the case.

But with octopuses, some of them, you'll see some of them. You want, so, is this something that the animal picks up? Wait, this works. This one isn't food. This one's actually useful. In a way that size of fish would be food, like everything is for octopus potentially food. But that's not the type of interaction that they have.

In other words, it's not something you see in every octopus of a certain species, which means it's probably something they're learning to do on the fly. And the other last example of how smart octopuses are is that apparently they're pretty good actors. Restarctor alec Schnell.

So there's another octopus in the same area. It mimics other animals, and so this is the mimic octopus, and it will mimic not only the appearance but also the behavior of other animals, so it might look like a flatfish, a lionfish, or a sea snake. And what's really interesting is they tend to do it depending on who's watching.

No kidding, that's incredible. Yeah, So they can not only change the patterns, but they can sort of morph into these other animals. Yes, okay, but now you're probably pretty convinced that octopuses and cuttlefish are fairly smart. Now we're going to tackle two questions about that. First is why are they so smart? As it turns out, this is a huge puzzle for octopus scientists because octopuses don't live very long. Here's how doctor Jennifer Mather puts it.

Because the octopus only loves a year or two.

Really wow, yes, so short lived?

And this always bothers us. Why do they have to be so smart when they're so short lived?

But why does it bother us?

With the normal model you would have would be that it would be good for you to have a long life span because there would be lots of things that you learned and loss of time to learn them. But if you're not gonna live very long, why learn so much?

Uh huh?

So that bothers us?

It doesn't make sense. So a typical octopus only lives about a year or two, which makes being that smart and being able to learn so much seem kind of a waste. Why would the octopus evolve to be so smart if it's not gonna live very long? Now that's an open question. We don't know the answer, but one theory is that maybe we're just looking at it the wrong way.

Most species live one to two years. They're like the rock stars, you know, live fast, die young. And also they don't have parental care, so they're not learning from kin, they don't live in groups, they don't learn from individuals around them. So what we think is that that's probably a reason why they are such advanced learners, because they take every opportunity that they can to learn from the

Do they have to learn on their own? Yeah? Wow. So whereas with us and other smartish animals like cats, dogs, crows, we became smart because we had long lives and lived in complex societies or groups of animals, the opposite might have happened in octopuses because they have such short lives. Because octopuses live on their own, they had to get smart to survive, which tells you that there's no one way to get to intelligence. We tend to think of

I think intelligence is an involved function of the necessity to solve the world, right, to get through life. It doesn't lie in a certain brain area because the brain areas that have it are so completely different than different animals. Right, So it's an evolved solution to similar problems, and you can build up to it in different ways. Yeah, you obviously life has managed to reach the solution several times. In a way. It's a product of living.

I guess, which kind of makes you wonder what would happen if octopuses could live longer?

I know, I always think about how terrifying or cool it would be if cephalopods lived for really long. Surely they'd take over the world.

You just made me a little scared there, all right. The last question I asked our experts was how smart exactly are octopuses and cuddlefish? How do they compare to other species or even to us. If you had to compare the intelligence of an octopus to another reference animal. Would you say something like, it's smarter than a cat, it's smarter than a dog or a three year old human? What would you say.

Then? I would probably politely decline. I mean, I think it's a very human way of thinking about it. In a way, what is it smarter than?

It's not useful to compare.

No, it's not really useful to compare. They all have a set of tasks to solve, and each one of them has a different way of solving them.

There's many ways to define intelligence. Intelligence is not one thing.

I think that it's also a bit misleading to rank their intelligence on a human centered scale. So I like to say that each species has evolved to be a master of its own domain. Octopuses excel at things that a human could never do, complex three dimensional navigation, manipulating objects with eight different arms, and their cognitive abilities reflect a very different, but equally I think sophisticated form of intelligence.

I see and so they're somehow able to process a lot of sensory information in the way that we could never even maybe imagine. Okay, so you wouldn't try to quantify their intelligence relation to other animals, Like if I ask you, are they smarter than a dog? Are they smarter than a three year old human?

I think you can quantify it. I just don't like to rank them, so, you know, and sometimes I get that a lot, and I just say, look, you know, cattlefish can wait for a better trait for two and a half minutes. How long can your yeah, your three year old break a second marginal?

Okay? In the episode, I'm going to let doctor Mather have the last word. If you had to sum up fifty years of studying octopuses, what's the thing that you would most want people to take away?

That's they're very smart, that there are many ways of being smart, and that many different animals are pushed in many different directions by their environment. There's a wonderful varietio there, and I'd love to learn more about it.

Thanks to all our experts joining us, and thank you for wrapping your arms around this mystery with us. See you next time you've been listening to Science Stuff. Production of iHeartRadio written and produced by me or Hey Cham, edited by Rose Seguda, executive producer Jerry Rowland and audio engineer and mixer Chandler Mace. And you can follow me on social media. Just search for PhD Comics and the