Published October 10, 2013
It turns out African elephants really do get the point. New research suggests these gray pachyderms can follow human gestures—like pointing—just as dogs are able to follow when we point to food or toys. An elephant's ability to understand such gestures could help explain how humans have been able to use them as work animals for thousands of years.
Humans point and respond to pointing gestures from infancy. It's one of the earliest ways we learn to communicate. Many domesticated animals such as dogs, cats, goats, and horses are also able to interpret human gestures. But among wild animals, even some of our closest relatives—such as chimpanzees—struggle to respond to our gestures. (Related: "Can Dogs Feel Our Emotions? Yawn Study Suggests Yes.")
Now, a new study has shown that African elephants are able to correctly interpret human pointing gestures, even without being specifically trained to do so.
"Elephants appear to be unique in that they're so useful when trained, and yet have never been selectively bred in captivity," said study co-author Richard Byrne, a researcher at the University of St. Andrews in Scotland, who studies the evolution of cognitive and social behavior.
Following the Point
Byrne and co-author Anna Smet, a doctoral student at the University of St. Andrews, studied 11 captive African elephants, whose usual job was to give tourists elephant-back rides at a site near Victoria Falls in southern Africa.
In their initial experiment, Smet stood midway between two containers, one of which contained food. Smet used her arm to point toward the container with food, while looking back and forth between an elephant and the bucket.
The elephants were significantly more likely to choose the container that Smet was pointing toward, the researchers report in a study published October 10 in the journal Current Biology.
The animals continued to prefer the container Smet pointed to even when she varied her position—moving closer to either one container or the other—suggesting that they weren't just picking a bucket based on her body position.
When the researchers tried out different pointing gestures, they found that the elephants responded successfully to the direction of Smet's forearm, hand, and index finger, but not to the direction of her gaze alone.
While human infants are able to interpret gaze direction, an elephant's eyesight probably isn't good enough to do this, Byrne explained.
When researchers compared their results from all the trials, they found that there was no difference between how successfully elephants interpreted gestures in the first half of the trials versus the second half. "So [the elephants] certainly weren't learning during the experiment," Byrne said.
Byrne also tried to figure out whether the elephants could have learned to interpret pointing gestures before the trial, either from their handlers or from other humans around them.
The animals were all trained, but were taught to respond to their handlers' vocal commands rather than their gestures. When Smet spent three months carefully observing the handlers, she did not see them using pointing gestures with the elephants.
"If they learned this ability from humans, it's a mystery to us when they did it," Byrne said.
Pointing in the Wild?
It's not that surprising that elephants are able to react to human gestures, said Phyllis Lee, a psychology professor at the University of Stirling in Scotland, who has carried out field research on wild elephants.
"It's not unexpected, given that there's good evidence that they can react to the physical cues of other animals and their social companions," said Lee, who was not involved in the study.
Elephants need to understand signals from their social companions, and they might respond to the pointing gestures in the experiment because "this thing that looks kind of like a big trunk, waving at a food bucket, might be the sort of thing that elephants attend to," Lee said.
Elephants have been known to use their trunks for social communication, but it's unclear if they interpret trunk gestures as pointing.
"When they detect something alarming, they characteristically face towards it and raise their trunk above their head with the tip of the trunk pointed to [the danger]," Byrne said. "We've always thought they were sniffing the breeze, but maybe they're also pointing; our results suggest that's more than possible." (Related:"How to Scare Elephants—For Their Own Good.")
A previous study of Asian elephants found that they didn't respond to human pointing cues. But that study's contradictory results may have been due to differences in experimental methods and in the level of prior training the elephants received, according to both Byrne and Lee.
"I would be surprised if the reason for the different result is that Asian elephants can't understand pointing," Byrne said.
While the current study of trained and captive African elephants could explain why elephants have been so useful for humans, "it doesn't tell us that much about what wild elephants are cognitively capable of doing," Lee said. "Understanding how wild elephants communicate would be extremely interesting, but we need to do those studies in the wild." (Related: "Name That Elephant: How to Identify Elephants in the Wild.")
That's something Byrne hopes to look at in the future: to see if wild elephants use pointing gestures. "Evolution doesn't select for abilities that are [of] no use naturally, so it implies that the elephants must be able to understand their own behavior as pointing. It would be nice to go on and find exactly how elephants point for each other," he said.
~National Geographic
Go make a difference!
No comments:
Post a Comment