Juvenile chimpanzee with tool from WBEZ on Vimeo.

In the latest episode, Elizabeth Lonsdorf of the Lincoln Park Zoo explained that everywhere chimpanzees are studied, they use sticks to investigate their surroundings. In a zoo setting this is pretty easy to see, but studying apes in the wild can be a little trickier. There is a lot of ground to cover, and the apes don’t always cooperate for their human audience.

In recent years, researchers started using the “Candid Camera” approach, leaving video cameras behind to capture chimp behavior.

The goal is to capture the apes acting naturally in a wild environment. But when a camera is discovered, the chimps’ natural curiosity is evident. In the video above, a juvenile chimpanzee is seen approaching the camera with a stick in its mouth.

Just as Dr. Lonsdorf described, the chimp takes a close look at the camera, then pokes it with a stick before she dares touch it with her finger.

Though our story focused on chimpanzees, scientists are interested in other great apes, too. After the study with chimpanzees and the artificial termite mound was complete, they conducted the same experiment with Western Lowland Gorillas.

Gorillas, unlike chimpanzees, are not known to use tools in the wild. When the gorillas were introduced to the habitat with the artificial termite mound, some figured out how to “termite fish,” while others never did.

So were some of the gorillas just dumb or what?

Lonsdorf and her colleagues proposed that it had nothing to do with intelligence.

The reason not all the gorillas performed the task was because their social behavior is so different from chimps. Basically, chimpanzees hang out together in close groups and gorillas don’t. They like much more personal space. So while chimps would watch each other closely and learn, it would be unnatural for gorillas to act this way.

The zoo continues doing cognitive research with the gorillas. The public can watch gorillas using a touchscreen to test their intelligence. They play a memory game where they must put different symbols in a correct order in exchange for treats.