Scientist Rates Bird IQs

ByABC News

Feb. 24, 2005 — -- Louis Lefebvre knows a bird brain when he sees one. In fact, Lefebvre, an animal behaviorist at McGill University in Montreal, has even come up with an IQ test for birds that has allowed him to create a pecking order in mental abilities among our fine feathered friends.

It's not that he's all that taken with birds. What Lefebvre is studying is intelligence and how it evolved among various species, including humans. Of particular interest to him is the correlation between brain size and intelligence, which has fascinated scientists for decades.

He turned to birds because, well, they're different from you and me.

"If we only look at primates the kind of intelligence we'll be studying might be too similar to our own," he says. So he turned to birds because they are so different from us there's less likely to be a "culture bias" in attempting to understand their intelligence.

Lefebvre thinks he knows which birds out there are the smartest, but he readily admits his research is not all that conclusive. Experts disagree fiercely even over the definition of intelligence, so there has to be some wiggle room here.

"We don't know what intelligence is in humans, much less other animals," he says.

For purposes of his research, Lefebvre defines it as "innovativeness" or the ability to adapt to different challenges. That at least allows him to "put a number on it," which is a measurement of innovativeness, and quite possibly intelligence.

So for the record, the smartest bird in the world isn't your expensive parrot that has learned how to repeat your private comments at the most inopportune time. It's just the common crow.

That won't surprise bird lovers who have long marveled at the cleverness of this member of the corvidae family. There are many celebrated cases of innovativeness among crows, which are known to manufacture tools to accomplish varied tasks.

Perhaps the most famous is the Japanese carrion crow that is clearly over the top when it comes to bird IQ. These crows routinely perch at traffic intersections near a university campus in Japan and wait for a red light.

When the traffic comes to a halt, the crows fly down and place walnuts in front of the tires. The light changes, the cars move out, crushing the nuts. The crows then dine, happy to parcel out that part of the task to someone else.

But one case, as convincing as it may seem, isn't very conclusive. Lefebvre needed many cases, involving many species, in many areas of the world.

So he has spent years combing through a unique resource. Birders around the world regularly report unusual behavior among specific bird species to birding and ornithology journals. Birders are often as knowledgeable as professional ornithologists, and their observations provided Lefebvre just what he needed.

The reports revealed a wide range of innovative behavior among many different species. Bald eagles in northern Arizona, eager to get at minnows trapped in ice-covered lakes during the lean days of winter, have learned how to crack the ice with their beaks. Then they jump up and down on the ice to force the minnows up through the cracks.

The gila woodpecker in the American Southwest and Mexico makes a wooden scoop out of tree bark to carry honey home to its young.

In Britain, there's the now-famous case of the European blue tit, which has learned how to peal off the tinfoil on milk bottles left on doorsteps and pig out on the cream. New Zealand house sparrows dine on cafeteria food by triggering a motion sensor that opens the door.

Pretty clever, to be sure, but do such acts really set one species above others?

Lefebvre developed an elaborate statistical model in an effort to come up with reliable numbers. Rather than simply accepting a few examples of innovative behavior as proof of intelligence, he compared the number of reports of unusual behavior with the number of birds of each specific species.

There are lots of crows, and much fewer quail, for example, so it would require many examples of crow innovation to outrank quail. And there were many. So many more that crows came out well above the mean for all birds, and quail came out well below.

What that means is crows are a lot smarter than quail, if intelligence is indeed expressed in innovative, or problem-solving, behavior.

Of course, people who have birds for pets are likely to find serious fault with all this. The family parakeet just has to be smarter than a crow, right?

For whatever it's worth, Lefebvre says we probably think our pets are a lot smarter than they are because they "interact" with us. We are likely to think a bird that seems to like us, or mimic our actions, must be pretty smart.

Lefebvre says he has found a correlation between brain size and intelligence among birds. Birds with large brains, relative to the size of their bodies, generally scored higher on his IQ test than others.

Parakeets are "small bodied parrots," so they have a relatively large brain for their size, and that means they are pretty smart. But probably not as smart as parakeet owners think they are.

But, Lefebvre says, there's lots more to IQ than just brain size.

"It's not absolute," he says.

And more than a few mysteries remain.

Parrots, which are clearly smart birds, are inconsistent, for instance. In South Africa, Lefebvre says, they don't have a clue as to how to innovate. But in Australia, they innovate like mad.

Lefebvre says he doesn't know why that's the case. It could be, he says, that they're really innovating all over the place, and we aren't smart enough to see it.

Lee Dye's column appears weekly on A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.

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