Do Animals Think?

At times, your pet may appear to be deep in thought. But don't let that pose fool you. Animals often do things that may make you think they're thinking.

Thinking about thinking is tricky, because thinking isn't something you can see. It goes on inside the brain. We know when we're doing it. But who can tell if an animal is thinking? It's not easy.

For example, check out the animal actions below. Do they show that the animals are thinking—or not thinking? What do you think?

A bird builds a nest that's just right for its eggs and babies.

An octopus uses its arms to open ajar with food inside.

A lion sneaks around behind its prey and then chases it toward another lion that's hiding and waiting.

What Is Thinking?

It may be easier to first explain what thinking isn't. For example, it isn't needed for things animals do automatically—like when a beaver dams a stream with sticks, mud, and grasses.

The beaver is making a pond, but it didn't learn how to do that. It doesn't think about doing it, either. Some animals just do what they do—kind of like robots—and they do it the same way every time. Scientists call this kind of behavior instinct.

But what about when an animal does learn to do something? Is that thinking? For example, you can teach a dog to give you its paw and "shake hands".

But most scientists don't believe that the dog is thinking when it learns such tricks.

Thinking Tests

For a long time, scientists didn't study animal thinking. Most of them didn't believe that animals could think. They thought humans were the only thinking animals.

Now more scientists are studying this subject. But it's very hard to prove things that no one can see or measure. So some scientists decided to take a look at brains.

Is bigger better? No. Cow brains are bigger than dog brains, but that doesn't make cows smarter than dogs. And squirrels have some of the biggest brains of all for their body size. But squirrels aren't even close to being the smartest animals in the world. So the size of a brain may give some clues about brain power, but it doesn't prove anything.

Other scientists study thinking by watching how animals solve problems. They watch animals in the wild. Or they set up thinking tests in a lab.

For example, a scientist might put some food just out of an animal's reach. One kind of animal may grab a stick and use it to slide the food over. Another kind might not be able to figure out a way to get the food. Some scientists think animals that have lots of problems to solve must be smarter than animals with simple lives.

Scientists also study certain kinds of behavior for clues about thinking. They watch for three things: whether animals use tools, how they act with each other, and how they communicate.

Animal Talk

Many animals communicate, or "talk"—with sounds, odors, colors, body language, and other signals. Communication helps animals get along with each other and survive.

For example, honeybees do a dance in the hive that "tells" other bees where to find food. And birds sing songs that say, "This is my place." Most scientists would say that this kind of "talking" is automatic and doesn't take any thinking.

Other animals, such as wolves and whales, use many different sounds and signals. Are these animals able to tell each other what's on their minds—the same way that people do with language? Do they think about what they're "saying"? Some scientists think so, but most agree that there's no way to tell for sure.

We know that human language takes thinking. So some scientists have tried to see what animals can do with our language. For example, a few apes have been taught sign language. The scientists who work with them say the apes seem to understand how the words work together. The apes sometimes even make up their own sentences. These could be clues that the animals are thinking.

And then there's Alex. Alex is an African gray parrot. Like any parrot, he can copy the human voice. But this is one parrot that just might know what he's talking about!

Alex seems to understand and use human words in the correct way—not just copy them. That makes some people feel that Alex—and the apes that use sign language—must be thinking animals.