(speaker) Most of the time, we see dolphins in aquariums or in zoos or in captivity, so we often think of them as super intelligent animals because we watch them do tricks and appear to solve these complex problems.

(speaker 2) But measuring intelligence involves so much more than just jumping through a hoop for a reward.

[cheerful music playing] Welcome to Animal IQ.

In each episode, we rank the intelligence of an animal based on our five domains.

This rubric gives us a way to indicate where science thinks an animal might fall based on current research.

But dolphins?

I mean, we've known about their smarts for decades.

Remember Flipper?

(Natalia) I do remember Flipper.

I used to love watching the reruns as a child.

The dolphins could communicate, they could rescue people, they could solve problems, they could do tricks, they would even fight crime.

And while the show did kind of overestimate the skills of the bottlenose dolphin, when taken together, the 49 species of dolphin are impressively intelligent.

We've been using EQ, or encephalization quotient, in this show, and the dolphin has a very admirable 4.9.

EQ is the brain-to-body-size ratio.

And while it's not a direct measure of intelligence, it is an indicator.

Remember though, humans are 7.5.

And that doesn't mean that dolphins are almost as smart as us, but they are extremely intelligent.

And one way to measure their intelligence is with a rational measure, like the ability to count.

So, researchers taught dolphins to distinguish between few and many.

To put it simply, they would put white dots on a board in groups, so say two dots on the left and ten dots on the right, and the dolphins would have to pick the group with fewer dots, so two versus the ten.

And at first, the researchers would always give them the same sets of numbers.

But eventually, they did start mixing it up, and dolphins still got the concept.

And it showed that they could count.

It wasn't that they were doing one, two, three, four, five, they were understanding the concept of less versus more.

And if you looked at two cookie jars, you, even as a very young kid, might understand which jar had more cookies.

But this research indicates that dolphins could do this, too.

They could understand the scale of numbers.

And that would seem to fit in our rational measure.

So we'd have to give that skill a pretty good bump.

But is this rare, Natalia?

I wouldn't say it's rare, but it is impressive.

Some land mammals and birds can do this.

Lions are more my wheelhouse, so I called a dolphin expert to find out more.

These are animals that have the second largest brain, relative to their body size, next to humans.

And they have really complex brains.

So my work is trying to figure out what are they doing with these big brains?

What's particularly interesting about dolphins is they're highly cooperative, they show caregiving and empathy for others.

We've seen this when we've worked with dolphins in aquaria, where if a dolphin was injured, we'd actually see others going without eating to hold up this injured or sick animal.

And that's been reported since the '60s.

(Trace) That's Diana Rocha, a second dolphin expert that we called for this episode.

One Diana, just not enough.

So they live in a fission-fusion society.

Within that society, they have strong bonds.

So not just a mother and a calf.

And they will have strong bonds that we call for life bonds.

We have males, usually two to three, that stick together for hunting, for defending.

They might join the rest of the group at certain times, especially during social, sexual, and the mating season.

They have that self-awareness and awareness of the other within their-their group.

(Reiss) We've also done other studies.

We gave dolphins an underwater interactive keyboard, and it had different visual symbols on the face of the keyboard.

And if the dolphin pushed, let's say, a triangle, it would hear a particular computer generated sound, something like this.

[whistles] And it would get a ball.

What the dolphins basically did was they started to imitate the signals very rapidly.

They actually did what we call segmentation.

So instead of doing the whole... [whistles] ...they just did the very end.

And then they produced the beginning the next time, and then they put it all together.

And they started using these sounds, these what we called facsimiles, in behavioral ways.

Dolphins even understand the signature whistles of each other.

So in captivity, dolphins are moved around from zoo to zoo or aquarium to aquarium, and researchers wanted to know whether or not dolphins remembered somebody that they had lived with before.

So they would play the signature whistle of a dolphin that had previously been at that zoo, and the other dolphins would swim up to the speaker as though they remembered the whistle of the dolphin they hadn't seen in years.

And that actually happened with one pair that was separated for over 20 years, which is so incredible.

And it bridges that rational and social measure.

(Natalia) They are doing so well on the rational and social; their scores are really high.

But social is one place where dolphins really and literally sing.

They use vocal sounds to address each other.

And they have those signature whistles that Natalia mentioned, and they use those audio cues when communicating with each other.

(Natalia) And not only do they communicate with each other, but they also socially learn from each other.

What they do is like we also do, we learn by copying.

So the small ones, the youngsters, they learn by copying the adults.

And they learn how to identify danger, food.

They learn how to assess their environment like that.

Dolphin mothers will change their food foraging behavior when there are calves around.

Almost like the dolphin mom is saying, "Okay now, kid, come over here.

And you see this?

And there's a fish."

And more research is needed to confirm that that's actually what's happening, but it's still really important on their social measure.

So we have some insights now at looking at human whistled languages, and where information is embedded, how information is conveyed.

So we're just at the beginning of this, and I'm very excited about this.

They can even understand the pointing cues of their trainer.

So if their trainer points at an object, a dolphin knows to go to that spot.

(Trace) And that's way better than some animals, like cats.

My cat cannot do that at all.

And dogs are pretty good at it.

Dogs are great at this.

They're even better than chimpanzees.

Dolphins in Australia even know how to use tools in the wild.

So what the dolphins will do, is they'll take a sea sponge off the floor and put it over their rostrum, that's what we think of as the nose, and this will protect their rostrum while they're digging around in the rocks for fish.

Mothers will teach their offspring to do this, and not all dolphins learn this behavior.

And that shows they know how to learn from each other, just like humans do, whereas some might learn to change their own oil or order pizza over the phone, other humans might not know how to do that.

And I'm one of the humans that is bad at ordering pizza over the phone.

But what all of this tells us is that so far, dolphins' social, rational, and ecological scores seem to be pretty off the charts.

And then there are other measures of intelligence as well, like the mirror test.

We've talked about this in a few different episodes, so I won't get into it too much, but it shows a complex understanding of self in the awareness measure.

When we mark a spot on the dolphin's body and show them a mirror, they know that they are looking at themselves.

And they pass this test at around two years old.

But researchers think they can see themselves and know it's them at about six months.

Dolphins might actually show the emergence of mirror self-recognition at a younger age than humans.

Humans show it in between about 18 and 24 months of age.

And dolphins are born in a highly precocious state.

They have to hit the water running, or I should say hit the water swimming.

Their social awareness is more advanced, their sensory motor development is more advanced.

So all of this happens at an advanced rate in dolphins.

For our X-factor, I'm gonna give them an even bigger boost.

I think we've only scratched the surface of dolphin cognition.

They have complex responses to death.

It seems like they understand if an individual is sick or injured.

They also have really impressive echolocation skills.

They'll bounce sound waves off their prey.

They cooperate while hunting and have specialized roles, so one dolphin will drive the prey while the other dolphins form a barrier.

And all of this suggests a complex understanding of themselves, of space, of communication, of individual roles, and of course cooperation.

They can even cooperate with non-dolphins, working together with humans to catch fish.

On top of all of that, they can pass that cooperative task we've talked about in other episodes with elephants and otters.

But instead of pulling rope to get their treat, they could push a button.

And they understood it was cooperative and would wait for another dolphin to push two buttons at roughly the same time.

(Natalia) So overall, the dolphin is ridiculously intelligent, not to mention that their brain-to-body-size ratio is second only to humans.

Now, they're not gonna pop out of the sea and start doing your taxes, but there has been research to see if we can communicate with dolphins.

And as we get more experiments done, we'll learn more about these amazing animals.

So what do y'all think?

Did we get it right?

Are dolphins as smart as we think they are?

Let us know your thoughts over on social.

And thanks everyone who suggested that we look into the dolphin in the first place.

It's always great to see your mentions and see what you want to know more about.

So keep it up and we'll see you next time on Animal IQ.

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