She Can Whistle? Hear, Hear!

At the Zoo, Orangutan's Unusual Talent Is Helping Scientists Learn About Apes and Humans

Having trouble learning how to whistle? Perhaps you can get a few tips from Bonnie, the National Zoo's whistling orangutan. Video by National Zoo
Wednesday, March 4, 2009

Having trouble learning to whistle? Perhaps you can get a few tips from Bonnie, the National Zoo's whistling orangutan.

An orangutan that whistles?

Yes, and there's more.

Bonnie often walks on two legs, like humans. And you can find the 32-year-old great ape copying her keepers by sweeping the floor of her zoo home with a handful of hay. Sometimes she grabs a rag to clean the windows.

"Orangutans in general are incredibly intelligent, but Bonnie is definitely even more so," said Erin Stromberg, a great-ape keeper who works with Bonnie and recently wrote a research paper about her ability to whistle. "She never misses a beat. She is highly intelligent and very inquisitive."

The 142-pound Bonnie is one of six adult orangutans at the National Zoo. Orangutans are primates, a group of animals that includes monkeys, gorillas and, yes, human beings!

Primates are mammals with large brains and opposable thumbs, which allow them to grasp something and hold on.

Bonnie and other great apes are part of a research project at the zoo's Think Tank. Scientists there are trying to learn more about the way the great apes think and act.

One part of the project is to learn whether orangutans can develop a strategy to remember long lists.

Stromberg helped with a project on Bonnie's unusual ability to whistle. Years ago Bonnie started to whistle, probably after hearing a keeper do it. In the project Stromberg made different whistling noises to see if Bonnie could repeat them. She did.

Orangutans aren't known to whistle and had been thought to have a set number of sounds. Bonnie's whistling shows that some apes have the ability to learn a new sound from another species.

Why is that important?

Because, Stromberg said, it can help scientists better understand how human speech developed. Great apes, after all, are the closest relatives to human beings in the animal kingdom, she said.

Bonnie was born in 1976 at the Albuquerque zoo in New Mexico and arrived at the National Zoo in December 1980. Bonnie has physical traits common to orangutans: a large belly and a forehead that slopes out. Her dark-red coat is almost burgundy, which makes her easy to spot on a visit to the zoo.

She is the mother of Kiko, who also lives at the zoo. And when an orangutan named Kyle arrived a few years ago, Bonnie "adopted" him and took care of him as he got used to his new home.

For breakfast, she likes to eat a big salad of greens, carrots, broccoli and other vegetables. During the day she eats hay, sometimes with popcorn thrown in, as well as fruits and a biscuit.

Orangutans like to stay indoors when it gets too cold. So the keepers bring the snow to them after a storm like this week's.

"They are smart," Stromberg said. "They like playing with the snow in the confines of their own warm space."

-- Valerie Strauss

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