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 ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.