The Science Is In: Elephants Are Even Smarter Than We Realized
Feb 26, 2014 | By Ferris Jabr
Elephants walking in line in
Amboseli National Park, South Kenya.
One day in 2010, while taking a stroll in his backyard, Kandula the elephant smelled something scrumptious. The scent pulled his attention skyward. There, seemingly suspended in the air, was a sprig of bamboo decorated with bits of cantaloupe and honeydew. Stretching out his trunk, he managed to get the fruit and break off a piece of the branch, but the rest of the tasty leaves remained tantalizingly out of reach. Without hesitation he marched straight to a large plastic cube in the yard, rolled it just beneath the hovering bamboo and used it as a step stool to pull the whole branch to the ground. Seven-year-old Kandula had never before interacted with a cube in this manner. Determined to satisfy his stomach and his curiosity, he did something scientists did not know elephants could do: he had an aha moment.
A couple weeks earlier a team of researchers led by Diana Reiss and Preston Foerder, then at City University New York, had visited Kandula’s home at the National Zoo in Washington D.C. They placed sticks and sturdy cubes around the yard and strung a kind of pulley system similar to a laundry line between the roof of the elephant house and a tree. From the cable they dangled fruit-tipped bamboo branches of various lengths both within and without of Kandula’s reach. After preparing the aerial snacks they retreated out of sight, turned on a camera and waited to see what the young elephant would do. It took several days for Kandula to achieve his initial insight, but after that he repeatedly positioned and stood on the cube to wrap his trunk around food wherever the scientists suspended it; he learned to do the same with a tractor tire; and he even figured out how to stack giant butcher blocks to extend his reach.
Other elephants had failed similar tests in the past. As it turns out, however, those earlier studies were not so much a failure of the elephant mind as the human one. Unlike people and chimpanzees, elephants rely far more on their exquisite senses of smell and touch than on their relatively poor vision, especially when it comes to food. Previously, researchers had offered elephants only sticks as potential tools to reach dangling or distant treats—a strategy at which chimps excel. But picking up a stick blunts an elephant’s sense of smell and prevents the animal from feeling and manipulating the desired morsel with the tip of its dexterous trunk. Asking an elephant to reach for a piece of food with a stick is like asking a blindfolded man to locate and open a door with his ear. “We are always looking at animals through our human lens—it’s hard not to,” Reiss says. “But now we have an increased appreciation of diverse thinking creatures all around us because of so much research on so many species. It’s fascinating to try and find ways of testing animal minds so they can show us what they are really capable of.”
People have been telling legends of elephant memory and intelligence for thousands of years and scientists have carefully catalogued astounding examples of elephant cleverness in the wild for many decades. In the past 10 years, however, researchers have realized that elephants are even smarter than they thought. As few as eight years ago there were almost no carefully controlled experiments showing that elephants could match chimpanzees and other brainiacs of the animal kingdom in tool use, self-awareness and tests of problem-solving. Because of recent experiments designed with the elephant’s perspective in mind, scientists now have solid evidence that elephants are just as brilliant as they are big: They are adept tool users and cooperative problem solvers; they are highly empathic, comforting one another when upset; and they probably do have a sense of self.
Despite the sharpened awareness of elephant sentience, many zoos around the world continue to maintain or expand their elephant exhibits and increasing numbers of heavily armed poachers are descending on Africa to meet the soaring demand for ivory, killing as many as 35,000 elephants a year. The U.S. recently banned ivory trade, with some exceptions, but there have been no steps toward outlawing elephant captivity. At least a few zoos are using the latest science to transform their elephant enclosures, giving the animals more room to roam as well as intellectually stimulating puzzles. Only some zoos can afford to make such changes, however, and many elephant experts maintain that, given everything we know about the creatures’ mental lives, continuing to keep any of them locked up is inexcusable.
The modern elephant mind emerged from an evolutionary history that has much in common with our own. The African bush and forest elephants, the Asian elephant, and their extinct relatives, the mammoths, all began to assume their recognizable forms between three and five million years ago in Africa. As Louis Irwin of The University of Texas at El Paso explains, both humans and elephants adapted themselves to life in Africa's forests and savannas around the same time, emigrating to Europe and Asia; both evolved to live long and often migratory lives in highly complex societies; both developed intricate systems of communication; and both experienced a dramatic increase in brain size.
Over the years numerous observations of wild elephants suggested that the big-brained beasts were some of the most intelligent animals on the planet. They remembered the locations of water holes hundreds of kilometers apart, returning to them year after year. They fashioned twigs into switches to shoo flies and plugged drinking holes with chewed up balls of bark. They clearly formed strong social bonds and even seemed to mourn their dead (see “When Animals Mourn” in the July 2013 issue of Scientific American). Yet scientists rarely investigated this ostensibly immense intellect in carefully managed experiments. Instead, researchers looking for evidence of exceptional mental aptitude in nonhuman animals first turned to chimpanzees and, later, to brainy birds like ravens, crows and some parrots. Only in the past 10 years have scientists rigorously tested elephant cognition. Again and again these new studies have corroborated what zoologists inferred from behavior in the wild.
Scientists living among herds of wild elephants have long observed awe-inspiring cooperation between family members. Related elephant mothers and their children stay together throughout life in tight-knit clans, caring for one another’s children and forming protective circles around calves when threatened by lions or poachers. Elephant clan members talk to one another with a combination of gentle chirps, thunderous trumpets and low-frequency rumbles undetectable to humans, as well as nudges, kicks and visual signals such as a tilt of the head or flap of the ear. They deliberate among themselves, make group decisions and applaud their achievements. “Being part of an elephant family is all about unity and working together for the greater good,” says Joyce Poole, one of the world’s foremost elephant experts and co-founder of the charity ElephantVoices, which promotes the study and ethical care of elephants. “When they are getting ready to do a group charge, for example, they all look to one another: ‘Are we all together? Are we ready to do this?’ When they succeed, they have an enormous celebration, trumpeting, rumbling, lifting their heads high, clanking tusks together, intertwining their trunks.”
Cynthia Moss, director of the Amboseli Trust for Elephants and another preeminent elephant researcher, once saw a particularly amazing example of elephant cooperation. One day the young and audacious Ebony, daughter of a matriarch named Echo, bounded right into the midst of a clan that was not her own. As a show of dominance, that clan kidnapped Ebony, keeping her captive with their trunks and legs. After failing to retrieve Ebony on their own, Echo and her eldest daughters retreated. A few minutes later they returned with all the members of their extended family, charged into the clan of kidnappers and rescued Ebony. “That took forethought, teamwork and problem-solving,” Moss says. “How did Echo convey that she needed them? It's a mystery to me, but it happened.”
In 2010 Joshua Plotnik of Mahidol University in Thailand and his colleagues tested elephant cooperation in a controlled study for the first time. At a Thai conservation center, they divided an outdoor elephant enclosure into two regions with a volleyball net. On one side stood pairs of Asian elephants. On the other side the researchers attached two bowls of corn to a table that slid back and forth on a frame of plastic pipes. They looped a hemp rope around the table so that when both ends of the rope were pulled simultaneously the table moved toward the elephants, pushing the food underneath the net. If a single elephant tried to pull the rope by him or herself, it would slip out and ruin any chance of getting the food. All the elephants quickly learned to cooperate and even to patiently wait for a partner if the scientists prevented both animals from reaching the rope at the same time. One mischievous young elephant outsmarted the rest. Instead of going through the hassle of tugging on one end of the rope, she simply stood on it and let her partner do all the hard work.
Some scientists studying wild elephants have argued that, in addition to cooperating for survival’s sake, the creatures are capable of genuine empathy. Poole recalls, for example, one elephant flinching as another stretched her trunk towards an electric fence; it was fortunately inactive at the time but had been live in the past. Elephants often refuse to leave their sick and injured behind, even if the ailing animal is not a direct relative. Poole once observed three young male elephants struggle to revive a dying matriarch, lifting her body with their tusks to get her back on her feet. Another time, while driving through Kenya’s Amboseli National Park, Poole saw a female elephant give birth to a stillborn baby. The mother guarded her dead calf for two days, trying over and over to revive its limp body. Realizing that the grieving mom had not had any sustenance this whole time, Poole drove near her with an offering of water. The elephant stretched her trunk inside the car and eagerly drank her fill. When she was done, she remained with Poole for a few moments, gently touching her chest.
When elephants encounter an elephant skeleton, they slow down, approach it cautiously, and caress the bones with their trunk and the bottoms of their sensitive padded feet. Elephants do not show the same interest in the remains of other species. In one experiment elephants spent twice as much time investigating an elephant skull as those of either a rhinoceros and buffalo and six times longer probing ivory than a piece of wood. Moss has witnessed elephants kicking dirt over skeletons and covering them with palm fronds.
Plotnik and renowned animal behavior expert Frans de Waal of Emory University recently teamed up to study elephant empathy. On a monthly basis between the spring of 2008 and 2009 they observed 26 Asian elephants at the Elephant Nature Park in Thailand, looking for signs of what researchers call “consolation.” Many animals are capable “reconciliation”—making up after a tussle. Far fewer animals display true consolation: when a bystander goes out of his or her way to comfort the victim of a fight or an individual that is disturbed for some reason. On dozens of occasions Plotnik and de Waal saw elephants consoling one another. A perturbed elephant often perks up its ears and tail and squeals, roars or trumpets. Over the course of the study, many elephants behaved in this way, because of an altercation, because they were spooked by something—such as a helicopter or dog—or for an unknown cause. When other elephants recognized these signs of anxiety, they rushed to the upset animal’s side, chirping softly and stroking their fellow elephant’s head and genitals. Sometimes the elephants put their trunks in one another’s mouths—a sign of trust because doing so risks being bitten.
The aspect of elephant intelligence that is the trickiest to gauge—the one that has really challenged scientists to think like an elephant—is self-awareness. Scientists now have preliminary evidence that elephants are indeed self-aware, overturning previous findings. To determine whether an animal has a sense of self, researchers first place a mark on an animal’s body that it can identify only with the help of a mirror. Then they wait to see if the animal tries to get rid of the mark when it encounters its reflection. Doing so, the reasoning goes, means the animal understands when it is looking at itself rather than another animal. In the earliest studies on elephant self-awareness, researchers placed a one by 2.5–meter mirror outside the bars of an enclosure, angled in such a way that the animals could see only the upper thirds of their bodies. The elephants reacted to the reflection as they would to another elephant, raising their trunks in greeting. When the scientists dabbed the elephants’ faces with white cream, the animals failed to recognize that the marks were on their own bodies.
But what if the experimental design itself prevented the elephants from understanding that they were looking at themselves in the mirror? After all, elephants identify one another primarily by touch, scent and sound—not sight—and the animals in the study could not physically investigate the mirror. So Reiss, de Waal and Plotnik decided to redo these experiments, this time allowing the elephants to use all their senses.
In 2005 the trio constructed a 2.5 by 2.5–meter shatterproof mirror and bolted it to a wall surrounding an elephant yard at the Bronx Zoo in New York City. Three female Asian elephants named Patty, Maxine and Happy were free to approach and inspect the sturdy mirror at their leisure. When they first encountered the contraption, Maxine and Patty swung their trunks over it and attempted to scale the wall to which it was attached, as though checking to see whether another elephant was hiding behind the glass. When they found nothing, all three elephants swayed their trunks and bobbed their heads while looking right into the mirror, just as we might wave our hands to see whether a shadow is our own. They stared at their reflection and stuck their trunks inside their mouths as though searching for snagged spinach.
A few days later the scientists painted a white X onto the right side of each elephant’s face. Maxine and Patty did not seem to notice the marks, but Happy began to touch the X on her face with her trunk after strolling past the mirror a few times. Eventually she faced her reflection and repeatedly swiped at the painted part of her face with the tip of her trunk.
The fact that only one of three elephants noticed the X on its face might seem a disappointing performance, but it is actually quite remarkable. Reiss points out that even in studies with chimpanzees—which most researchers accept are self-aware—sometimes fewer than half pass the mirror test. Plotnik argues that expecting elephants to pay attention to a random blotch on their face may not have been the best test of their self-awareness anyhow. Whereas chimpanzees are fastidious groomers that spend hours picking nits and gnats out of one another’s hair, elephants stay clean by getting dirty, routinely spraying themselves with dust and dirt to deter insects and parasites. And they love to galumph in mud. “There’s no reason to think elephants would have same kind of vanity," Plotnik says.
Brains behind bars
All the new evidence of elephant intelligence has intensified the debate about whether to continue keeping the creatures in captivity. Former elephant caretaker Dan Koehl maintains a thorough database of elephants around the world. He has records of 7,828 elephants currently in captivity: 1,654 in zoos or safari parks; 4,549 in "elephant camps" where tourists can ride the animals; 288 in circuses; and the remaining in temples, sanctuaries or private residences. The latest research on the well-being of U.S. zoo elephants is not particularly encouraging. With mny collaborators, animal welfare expert and Vistalogic, Inc., consultant Cheryl Meehan recently completed a gint study on nearly all of the 300 or so elephants in North American zoos accredited by the Association of Zoos and Aquariums (AZA). The researchers assessed the physical and mental health of captive elephants with a combination of photographs, videos, blood and hormone tests, veterinary reports, and surveys filled out by caretakers: about 75 percent of the elephants were overweight or obese; between 25 and 40 percent had foot or joint problems of some kind depending on the year; and 80 percent displayed behavioral tics, such as pacing and continual head bobbing or swaying.
Stephen Harris of the University of Bristol and his colleagues conducted a similar study on U.K. zoo elephants in the late 2000s. I asked him whether it is possible to keep an elephant physically and mentally healthy in a zoo. His answer was succinct: “No.” The elephants he studied spent up to 83 percent of their time indoors, often in cramped conditions; the majority had abnormal gaits; 75 percent were overweight; more than 50 percent had behavioral tics; and one individual displayed tics for 14 hours in a single day. Captive elephants also have higher rates of infertility and die younger on average than their uncaged counterparts. Whereas wild elephants migrate great distances through the forest or savanna in search of food and water—eating huge amounts of tough, fibrous grasses and shrubs that are difficult to digest—zoo elephants spend too many hours standing idle on concrete and consume calorie-rich foods they would rarely encounter in their native habitat. Researchers have also learned that many zoo elephants do not get the rest they need because they do not like to lie down and sleep on stone or other hard surfaces.
Few zoos can adequately re-create the complex social life of wild elephants. Female elephants in captivity are often strangers acquired from here and there. Any friendships that do form can dissolve in an instant when a zoo decides to relocate an animal. “Sometimes people treat these creatures like furniture,” Moss says. Researchers used to think that male elephants, which leave their clans in young adulthood, were loners. They now know, however, that male elephants socialize extensively with one another. Yet zoos mix males and females in ways that would never occur in the wild and try to offload adult males if they become too cantankerous or lustful.
Now that the evidence of the elephant’s intellect and emotional life is no longer mostly anecdotal the zoological community faces even more pressure to answer a daunting question: Why keep elephants in captivity at all? Zoos usually give two main reasons: to rescue elephants from dire situations, such as the threat of poachers or the stress of living in so-called rehabilitation centers in Asia that keep the creatures leashed to trees; and to teach the public how amazing elephants are, in hopes of promoting their conservation.
These arguments have become increasingly tenuous over time. Few elephants in zoos today were rescued from an awful life; instead they were born in captivity. In the mid-2000s zoos embarked on an especially aggressive captive elephant breeding program, trying to compensate for all the animals they had lost to disease and frailty. "For every elephant born in a zoo, on average another two die," concluded a comprehensive 2012 investigative report by The Seattle Times. As for educational outreach, modern technology has rendered zoos obsolete. “When I was a kid we had no television and even when we did wildlife images were very few,” Harris says. “You went to the zoo to interact with elephants, to ride on them and touch them—there was no other way to get a sense of them. Now of course there’s an information overload. You can get a sense of scale and see all kinds of wonderful behaviors from photography and films that you would never see in captivity.” Consider how much one can learn from vivid scenes of wild elephants in a nature documentary of Planet Earth caliber compared with the experience of staring at an arthritic bobble-headed zoo elephant.
Other scientists think that, even if there are few good reasons to keep elephants in zoos in the first place, arguing for an abrupt end to elephant captivity is naive and idealistic, especially outside North America and Europe. “Although I believe all elephants should be wild, unfortunately that is not realistic," Plotnik says. In Asia, where he works, people have been using elephants as beasts of burden for centuries and currently have thousands of the animals captive in camps. Suddenly releasing all those animals is simply not feasible; there may not even be enough wild habitat left to accommodate them all. Plotnik thinks the best way forward is maintaining the wild Asian elephant population through conservation and slowly phasing out the captive one by finding new, equally lucrative jobs for elephant caretakers. Moss wants something similar for elephants in zoos in the U.S. and Europe: “I would like to see them live out their lives and have no more breeding or importation.” Meehan hopes the kind of information she has collected will help improve the well-being of zoo elephants.
In recent years at least a few zoos have been trying to use animal welfare science to make their elephant enclosures more like sanctuaries. The Oregon Zoo in Portland is close to remodeling its elephant habitat in a way it claims will improve the livelihood of its four male and four female Asian elephants. Elephant Lands, set to open in 2015, is a hilly 2.5-hectare habitat covered mostly in deep sand rather than concrete and featuring a 490,000-liter pool for wallowing, bathing and playing. Elephants will be free to roam from one part of the terrain to another, explains elephant curator Bob Lee, which should hopefully allow males and females to interact as they choose. Various feeding machines will provide elephants with food at random intervals, because studies have linked such unpredictability to healthier body weights. Other feeders will exercise the elephants’ trunks and brains with out-of-reach snacks and mechanical puzzles.
Refurbishing elephant enclosures so they are roomier and more intellectually stimulating is at once an acknowledgment and dismissal of the research on elephant intelligence and welfare. After all, if the zoos really have the animals’ best interests at heart, they would close their elephant exhibits. In 2005 the Detroit Zoo became the first to give up its elephants solely on ethical grounds. Spending so much time in close quarters—and waiting out the harsh Michigan winters indoors—left their two Asian elephants physically and mentally ill. Wanda and Winky were moved to the Performing Animal Welfare Society's (PAWS) 930-hectare sanctuary in San Andreas, Calif. A handful of zoos have followed suit, but they are in the minority.
Ed Stewart, president and co-founder of PAWS, thinks that even his massive haven is not adequate to keep the elephants as healthy as they would be in the wild. "Elephants should not be in captivity— period," he says. "It doesn’t matter if it’s a zoo, a circus or a sanctuary. The social structure isn't correct, the space is not right, the climate is not right, the food is not right. You can never do enough to match the wild. They are unbelievably intelligent. With all of that brainpower—to be as limited as they are in captivity—it's a wonder they cope at all. In 20 years I hope we will look back and think, 'Can you believe we ever kept those animals in cages?'"