When animals go to school

What was the most improbable creature that you found actually learns things? The most apparently stupid?

Octopus and squid. They're invertebrates. They're not closely related to us at all. And they lack some of the things that are usually associated with learning ability. Most of the animals that are able to learn a lot learn when they are children, sheltered and protected by their parents. By the time an octopus hatches out of the egg, its mother has died. It has no parents to take care of it.

A giant octopus may live, like, four or five years. An animal with a short lifespan that isn't protected by its parents -- why would it have as much learning ability as octopus do? And they can learn quite a bit. They can learn by observing other octopus, which doesn't seem like something they would get much chance to do in the wild. So the fact that they can learn as much as they do is somewhat mysterious.

What sort of things does an octopus have to learn?

I don't think we really know much about what octopus have to learn. In the lab, they can learn from looking through a tank wall and seeing another octopus doing it. "Aha. So, that's how you open the jar and get the crab out." It may be that an octopus has a very complicated body. It's got 50,000 muscles and no bones to bounce them off of. They've got very complicated skin -- they can change the shape of features and patterns on the skin.

They also have, in some cases, many forms in their life. So a baby octopus is a little teeny thing you could hold in the palm of your hand, and a Pacific giant octopus gets to be a great big thing. And they catch different foods when they're at different sizes in their lives. So maybe they're using the learning to adapt to their constantly changing body shape and size, but that's just speculation.

Another thing that really surprised me that had to be learned is the very idea that you live in the forest. These animals that are raised in captivity and then are released don't just jump into the nearest trees, and go swinging off.

"Oh look, it's my natural habitat!"

Maybe it's a childish or romantic notion that of course they would just be free, run free!

Oh, absolutely. I was really amazed that Arjan Singh, who raised this leopard cub -- the first time he took this leopard into the jungle, its eyes got big. And essentially it said: "Let's go back to the house. This is scary. There could be monsters in there."

This happened to me when I was in high school. One of my teachers correctly surmised that I was just the sort of sucker to raise three orphaned possums whose mother had been hit by a car. And I raised them, at home, and one day I took them out into the woods thinking that they would love their natural habitat: the woods. And they took one horrified look at the woods and swiveled around and raced up my leg. Because the woods are scary. There are things out there that might want to eat possum.

That's another one: the idea that certain animals will prey upon you. The fact that you have to learn which ones they are, in some cases, seems so counterintuitive. Isn't knowing that one of the basic ways you stay alive?

Yes, it is. And I think that what is hard-wired in children and baby animals, I speculate, is a generalized fearfulness. I think we see that in children a lot, where we have children who are incredibly protected, and we try to make sure that no danger ever comes near them. And there you have a child who is terrified of fire trucks, who is terrified of bugs, who is terrified of imaginary creatures, bogeymen and werewolves.

I think that children -- human children -- have a natural need to be afraid, and if they're not supplied with bears and rattlesnakes, they'll find things in their world to be afraid of. Baby animals also have fearfulness, but they also have to be taught what to be afraid of. And this is something that people reintroducing baby animals into the wild have a terrible problem with. Because most baby animals are just like me. They say: "A fox! How cute!" And they don't think: "A fox! It's going to eat me."

They need to learn what to be afraid of. In the wild, they learn by watching their parents' reaction. If their parents shrink down to the ground and freeze when they see a fox, the baby animal instantly knows that the fox is bad news. If their parent freezes when they hear an alarm call, then the baby animal knows that the alarm call means something is scary. Seeing your parents afraid -- that's a very impressive thing to a baby animal.

Human beings are like some other animals in that we're not born afraid of snakes and insects, but we're born very easily able to learn to be afraid of snakes and insects. A monkey is not instinctively afraid of a snake, but if it sees another monkey act afraid when it sees a snake, then the monkey instantly learns. Whereas if it sees another monkey act afraid when it sees a flower, it won't. It's just not as easy to learn to be afraid of flowers as it is of snakes.

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