Researchers Preston Foerder, Marie Galloway, Tony Barthel, Donald E. Moore III, Diana Reiss studied the cognitive abilities of 3 housed at the Smithsonian National Zoological Park—a 33 year-old (Shanthi) and a 61 year-old (Ambika) pair of females and a 7 year-old juvenile adult male (Kandula).
From the authors paper Insightful Problem Solving in an Asian Elephant
Elephants have large complex brains [1], exhibit complex social behavior [2], show a facility with tools [3], and are generally thought to be highly intelligent [4]. Cognitive studies have demonstrated that elephants are capable of visual symbol discrimination and long term memory [5], means-end recognition [6], relative quantity judgment [7], mirror self-recognition [8], tool use [3], tool manufacture [9], and an understanding of cooperation [10].12
Studies of other animals, such as chimpanzees and birds have shown those critters to possess spontaneous problem solving skills. Reports and studies, at least until this one, have, despite the many other documented cognitive abilities demonstrated in both captivity and in the wild, have not shown elephants as insightful problem solvers.
In order to test the hypothesis that, considering their already demonstrated cognitive abilities, elephants should be able to demonstrate spontaneous or insightful problem solving skills the researchers designed a series of experiments that would elicit just such a behavior.
All three elephants were subjects of the first experiment. Subsequent experiments only included Kandula (the young male).
Apparatus.
A 7.62 m cable was run from the roof of the elephant house to a tree in the yard. The height of the cable was 6.25 m above the ground at its center. A movable shuttle attached to a rope pulley was positioned on the cable. Lengths of leafy bamboo with fruit attached at the bottom were hung from the shuttle by a trimmed branch so that they could be pulled or knocked off. Fruit was attached to the bamboo by impaling it on branches with leaves. Fruit is a preferred food and each length of bamboo had three pieces of fruit that was varied among melons (cantaloupe or honeydew), apples, bananas, and oranges.
In the yard were placed four 1.80 m lengths of bamboo sticks, two leaning against the tree and two on the ground beneath the food. In addition, Ambika and Shanthi were given an elephant “tub,” a round aluminum stand 0.61 m tall and 0.75 m in diameter. Kandula was given a 0.61 m plastic cube that supported his weight. Neither of these items were novel. Ambika and Shanthi had been previously trained to stand on the tub (see Table S2.). Kandula had previous experience with the cube as an enrichment toy. Different items were used because 1) the cube might not support the weight of the larger elephants and 2) Kandula, being more playful, might pick up the metal tub and throw it, creating dangerous containment issues. The platforms were placed approximately 1.80–3.66 m from the food placement. Exact distance and position varied.12
In the first experiment all 3 elephants demonstrated interest in the food hung above the compound. The females, Shanthi and Ambika failed to use the tools provided (sticks and the aluminum tub). Kandula did, however, demonstrate an 'aha' moment.
For several sessions, Kandula just stared at the hanging fruit, ignoring the stick as well as the cube that was nearby.
"He did not attempt to use a tool to reach the food for seven 20-minute sessions on seven different days," Hunter College's Reiss said.
"And then he finally had what looked to be this sudden revelation, and he headed right over to the block, pushed it in a direct line right underneath the fruit, and stepped right up on it and got the food in one swift movement.11
This video shows the elephant's first use of the cube as a tool to acquire food.
The next day, in session 8, approximately two minutes after the placement of the first unreachable branch, Kandula rolled the cube to the food area, stood on it, and obtained the food in the same manner as in the previous session. In addition to using the cube for food acquisition, he moved the cube and stood on it to explore the interior of an enrichment object affixed to a tree near the food site. At the session's end, he also rolled the cube to the yard's periphery and stood on it to reach for blossoms on an overhanging tree branch. During this session, he used the cube as a tool to obtain food or other objects a total of 9 times, rolling the cube from 2–10 turns in each effort.12
The second set of trials tested tood displacement. The researchers moved and even hid the plastic cube about the enclosure to see if Kandula would find and again use it to acquire the food. Kandula had no problem finding the plastic cube to reach the fruit.
This video shows the elephant retrieving the cube from a non-visible placement during the second session in which the
cube was placed in this position.
The third experiment wanted to see if Kandula could generalize his solution to another tool. Result: he did.
This video shows the elephant employing a tire as a tool to obtain food.
In the fourth and final experiment, the cube and tire was replaced by butcher blocks in an attempt to see if Kandula would stack at least 3 of the blocks in order to reach the prize. Kandula only managed to stack 2 of the butcher blocks which left him inches short of the food. He did, however, solve the problem in an unexpected manner. He used a large ball —a toy Kandula is quite familiar with, by the way (see the bonus video in the tip jar)—that the keepers placed in the yard as an enrichment item to balance on. Smart little elephant he.
This video shows the elephant stacking two blocks
in an attempt to acquire food.
The researchers were, at first, puzzled that the elephants hadn't used the sticks provided to reach the fruit. They realized (perhaps in their own eureka moment) that for elephants, who've demonstrated using sticks in other situations (back scratching, for example), using a stick in these tests would be an unnatural behavior.
because the mammals rely heavily on the trunks' sense of smell and touch when seeking out food. Holding anything in their trunks would prevent them from effectively feeling and sniffing out dinner, the researchers say.11
As noted, the older female elephants failed to solve the problem while Kandula in each case found an item to stand on to reach the fruit. "Perhaps they didn't care enough to try to get the fruit, or it could have been age-related,"11 Dr. Reiss of Hunter College suggests.
Kandula, on the other hand is inquisitive and intelligent according to Don Moore.
"Among the smart elephants—and all elephants are smart ... we think Kandula is one of the smarter ones," said Moore, associate director for animal-care sciences at the National Zoo.
Moore said he hopes the discovery will help raise awareness about the plight of Asian elephants, which are endangered.
"Studies like this can help people relate more closely to animals because it makes them more like us," he said. "If we can empathize with animals, we are more likely to help conserve them."11
This is fascinating science. It shows that we puny humans are not so substantially different from many of the other animals on this planet. Eventually, one hopes, the Golden Rule's "do unto others" will not, by default, exclude our non-human neighbors.
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