News in Science

Elephants smart as chimps, dolphins

Working together A study of elephants has found they not only aced a test of their intelligence and ability to cooperate, they found new ways to complete it.

The study, published in the latest Proceedings of the National Academy of Sciences, highlights not only the intelligence of individual elephants, but also the ability of these animals to cooperate and understand the value of teamwork.

Scientists now believe elephants are in league with chimpanzees and dolphins as being among the world's most cognitively advanced animals.

"Elephant sociality is very complex," says lead author Joshua Plotnik. "Social groups are made up of matriarchal herds (an older female is in charge), and varying levels of relatedness among members. Cooperation in elephants was most likely necessary in a context of communal care for, and protection of, young."

"In the wild, there are fascinating anecdotes of elephants working together to lift or help fallen members, and forming clusters to protect younger elephants," added Plotnik, a Cambridge University researcher who is also head of research at Thailand's Golden Triangle Asian Elephant Foundation.

Elephants tackle classic experiment

Tests of elephant intelligence and their other abilities are rare, simply because working with these large and potentially dangerous animals poses risks. To meet the challenge, Plotnik and colleagues Richard Lair, Wirot Suphachoksahakun, and Frans de Waal reworked a classic 1930s experiment used on primates.

The researchers positioned a sliding table, holding enticing red bowls full of corn, some distance away from a volleyball net. A rope was tied around the table such that the table would only move if two elephants working together pulled on the dangling rope ends. If just one elephant pulled, the rope would unravel. To get to the front of the volleyball net, the elephants had to walk down two separate, roped-off lanes.

A total of 12 male and female elephants from the Thai Elephant Conservation Center in Lampang, Thailand, participated. It's estimated that fewer than 2500 of these animals are left in the Thai jungle, so conservation efforts now are critical.

After quickly learning that the corn-on-the-table task could not be successfully completed solo, elephants would wait up to 45 seconds for the second "partner" elephant to show up. If the researchers did not release this second elephant, the first one basically looked around as if to say: "You've got to be kidding. It takes two to do this." In most cases, the elephants got the corn.

Thinking outside the box

Two elephants, named Neua Un and JoJo, even figured out how to outwit the researchers.

"We were pleasantly surprised to see the youngest elephant, Neua Un, use her foot to hold the rope so that her partner had to do all the work," Plotnik said. "I hadn't thought about this beforehand, and Neua Un seemed to figure it out by chance, but it speaks volumes to the flexibility of elephant behavior that she was able to figure this out and stick to it."

The other "cheater," JoJo, didn't even bother to walk up to the volleyball net unless his partner, Wanalee, was released.

"Perhaps he had learned that if he approached the rope without her, he'd fail," says Plotnik, adding that such advanced learning, problem-solving, and cooperation are rare in the animal kingdom. Other animals clearly engage in teamwork, but he thinks they are "pre-programmed for it," unlike elephants that seem to understand the full process.

Animal experts from around the world are praising the new research.

"This is the first experimental evidence for learned cooperative behavior in this socially sophisticated species," says Professor Diana Reiss of Hunter College in New York. Clayton says the findings support the theory "that cognitive abilities evolved independently in animals that are as very distantly related from us as elephants and crows."

Associate Professor Satoshi Hirata of Japan's Great Ape Research Institute was "amazed" when he first saw the videos of the elephant experiments.

"We tend to think that elephants and humans are greatly different," says Hirata, "but the study results show that we share some social mind skills with elephants."