Animals can have some surprising intelligence — crows are smarter than human children in at least one way and sharks have stunning memory. But the diversity of the animal kingdom means measuring their smarts is tricky, especially when trying to figure out if any one individual is smarter than another of the same species. Now, researchers in New Zealand have designed a series of tests to assess the intelligence of robins, reports Michael Balter for Science. Some of the tasks they used may give insight in how to design other IQ tests for animals.
Motivating a bird or other creature to do the test is a big part of the problem. Rachael Shaw, an animal behavior researcher at Victoria University of Wellington and her team test the motivation of their robins (not the red-breasted kind, but New Zealand’s North Island robin) by teaching them to jump on a scale and eat a worm before and after each IQ assessment. If they eat the worm, it means they are hungry enough to do the test.
Balter describes the tests themselves, which measured various aspects of animal cognition such as "the ability to acquire, process and act on information about the environment." He writes:
In a test of motor skills, for example, the birds learned to flip plastic lids covering wells in a wooden board, one of which had a tasty mealworm at the bottom. In another—designed to test their ability to distinguish colors—the birds had to figure out whether the worm was hiding under a red or a blue lid. To show they could distinguish symbols, they had to discern whether the worm was under a lid marked with a cross or a square. And because these robins store food for the winter, the scientists also measured their spatial memories. They saw how well the birds could remember in which of eight wells the researchers had hidden a worm.
Computer analysis of how well each bird did found that if an individual did well on one test, it was likely to do well on the others. In other words, together, the battery of tests were measuring the cognitive ability of each bird, not just their talent at each task. Between 34 and 45 percent of the individual differences on each test could be explained by each robin’s overall level of intelligence, the researchers write in Animal Behavior.
They argue that their tests of birdy IQ are similar to that that test human IQ. In humans, general intelligence accounts for about 40 percent of individual differences in performance. (The remainder means that some people really are just better at taking IQ tests, perhaps because of education.)
However, another researcher not involved in the work, Alex Thornton of the University of Exeter in the U.K., says that some of the tests could be assessing similar skills. “The extent to which the study really captures something analogous to general intelligence in humans is somewhat questionable,” he says.
Still, the tests by Shaw and her colleagues are better at sussing out individual differences than the online assessments people can give their household pets. Of course, owners are usually convinced that their Sparky or Ziggy is smarter than the average, no matter what the test says.