RENEE MONTAGNE, HOST:
This is MORNING EDITION from NPR News. I'm Renee Montagne.
LINDA WERTHEIMER, HOST:
And I'm Linda Wertheimer. In the 1960s textbooks still described humans as the only creatures to make and use tools. That changed in the '70s when Jane Goodall observed chimpanzees making and using tools. Now a new book tries to catalog the full range of tool use in animals. "Animal Tool Behavior" offers examples from wasps that tamp down soil with a pebble to elephants that throw stones at their enemies.
And the book says a lot of old ideas about animals and tools are simply wrong. NPR's Jon Hamilton visited the Indianapolis Zoo to speak with one of the authors.
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JON HAMILTON, BYLINE: I'm touring the exhibits with Rob Shumaker. He's vice president for Life Sciences here and also teaches at Indiana University.
ROB SHUMAKER: Well, we're approaching our polar bear exhibit and we have this adult female, Tundra, and she is about as beautiful as a polar bear can be.
HAMILTON: Shumaker says one goal of the book which he wrote with Benjamin Beck and Kristina Walkup is to correct some widespread misconceptions, like the idea that tool use is limited to monkeys and apes.
SHUMAKER: We have these great stories about polar bear tool use that are in the historical literature. And one of the stories we have is Polar bears getting up on a cliff and hurling great chunks of ice down on something like a walrus to kill it.
HAMILTON: Well, that's an anecdote. There's no doubt that Polar bears in zoos often throw objects with great force and accuracy. Shumaker says another common misconception is that tool use requires fingers, or at least hands.
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HAMILTON: He says no one bothered to tell dolphins they couldn't use tools.
SHUMAKER: They're really, really remarkable and to me what's so interesting about dolphins is they have nothing to hold tools with except their mouth and yet they are still innovative and creative.
HAMILTON: Shumaker says dolphin play with just about any object they find. But in this context, the objects are just toys. Something becomes a tool when it's used to manipulate another object or creature for a specific purpose. Jodie Baker is in charge of marine mammals. She says a dolphin named Kimo often manipulates people with a tool: a buoy.
JODIE BAKER: While we were talking, Kimo was coming over here with it. I was wondering if he was going to throw it out. Typically, if you walk by the pool and there's a dolphin playing with a toy, they'll typically throw it in your direction to get your attention.
HAMILTON: That's a form of tool use known as baiting or enticing. But Shumaker says scientists have collected lots of other examples.
SHUMAKER: One, is a dolphin that found a piece of tile, broken tile, and took it down to the bottom of their pool and used it to scrape algae off the bottom of the pool and then they ate the algae.
HAMILTON: Shumaker says you can also see tool use in wild dolphins, including some in Australia that flush out their prey with a sponge.
SHUMAKER: They hold the sponge on their rostrum, and then they use that as they disturb the sandy bottom to get fish like flounder that are down in the sand.
HAMILTON: One of the most widespread myths about tool use is that it is a sign of intelligence. Shumaker says some really smart animals do use tools, but so do creatures like the bolas spider, which hunts with a weapon made from same silk it uses to spin a web.
SHUMAKER: And when an insect flies by, they throw it and it attaches to the insect because it's sticky and they reel them in. It's very complex. Very impressive. Very dramatic. But all available information tells us that it's completely controlled from this animal's genetic history.
HAMILTON: It's programmed behavior, not something the spider figured out. Genetic programming is also the reason hermit crabs carry around another creature's shell and ant-lions throw sand at their prey. Shumaker says at the other end of spectrum are highly intelligent animals that rarely use tools.
SHUMAKER: We're standing in front of this really lovely troop of ring tailed lemurs.
HAMILTON: These lemurs are not only smart, they have fingers and opposable thumbs.
You'd expect that they'd be pretty good tool users, or pretty notable tool users and, in fact, they're not.
When intelligent animals do use tools, though, they often do so in very creative ways.
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TIM LITTIG: So we are overlooking the main elephant exhibit.
HAMILTON: Tim Littig is a senior elephant trainer.
LITTIG: This is Kubwa, 35-year-old Kubwa, and our latest baby, her latest calf, little Kalina who's approaching about seven weeks of age now.
HAMILTON: Kalina has been able to nurse without any help, but Littig says things were trickier with Kubwa's previous baby.
LITTIG: Her last calf was a little smaller than this one and required a stepstool to be able to reach her mammary glands to nurse. And Kubwa would move the stool around so the calf could stand up on the stool to nurse - to reach to nurse.
HAMILTON: Shumaker says this sort of creative problem solving with tools is sign of intelligence. So is figuring out how to make a tool, a skill many scientists once thought of as uniquely human. Shumaker says those scientists must not have spent much time around orangutans.
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SHUMAKER: You do have to not go up too closely because they can reach out pretty far and they'll take your equipment.
HAMILTON: Of course they would.
SHUMAKER: And your wallet.
HAMILTON: Right, yeah.
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HAMILTON: Several of the zoo's orangutans make it clear they'd like to have the microphone I'm carrying. Shumaker tells a female named Knobi that she can touch it.
SHUMAKER: Nice, soft microphone cover on that. But you cannot have the whole thing.
HAMILTON: When I move beyond her reach, Knobi fetches a small tree branch.
SHUMAKER: You're seeing Knobi right now. There's some tool manufacture. She's making a reaching tool to try and get your microphone.
HAMILTON: Knobi breaks off one fork of the branch so it will fit through the mesh around the enclosure. But the branch still isn't long enough, and she's determined.
SHUMAKER: Not too surprising, she now has a much bigger, stronger tool to come get the microphone. So she's gotten a full branch now.
HAMILTON: And this reaching tool gets the job done.
SHUMAKER: So there you go. So, she's doing her best to draw the mic in.
Knobi, we're not - I'm sorry you cannot have it. Good job with your tool. Thank you for that the - thank you for that.
We've got to publish that. Oh, wow. Now she's gone and got a much bigger, stronger branch. So we're going to leave now.
HAMILTON: Just 10 or 15 years ago, scientists were still debating whether orangutans in the wild also made tools. Now it's clear they do. And so do other species. New Caledonian crows make hooks out of twigs to catch prey. Wild chimpanzees make wooden spears for hunting.
Shumaker says the most surprising and controversial findings in the new book involve so-called symbolic tools.
SHUMAKER: These are examples where we see tools being used to represent something else, or to provide a change in psychological state.
HAMILTON: One simple symbolic tool that we use all the time is money. And some monkeys and apes in captivity have learned to use tokens for a similar purpose.
But Shumaker is more intrigued by symbolic tools that can affect emotions. There are lots of examples in people. Children often have a special stuffed animal or blanket that is much more than a toy. The object represents comfort or security to them, and they use it to feel better. And in the past few years, Shumaker says, scientists have been collecting evidence that some animals use symbolic tools in much the same way.
SHUMAKER: We would see great apes in times of great stress or sadness, like a female who had an infant that died, where that female would create something that researchers called a doll, and then treated it exactly as she had treated her infant that had recently died.
HAMILTON: Scientists are still debating the significance of examples like this. But Shumaker says the fact that such a debate is even taking place shows how much things have changed since the 1960s. That's when scientists first realized that humans weren't the only creatures using tools.
Jon Hamilton, NPR News.
WERTHEIMER: You can see a crafty crow bend a piece of wire into a hook and a persistent monkey cracking open a nut using a large rock as a hammer. Find those and a few more at NPR.org.
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WERTHEIMER: This is MORNING EDITION from NPR News.