BIRD EXPERIMENT SHOWS AESOP'S FABLE MAY BE TRUE
By MALCOLM RITTER, AP Science Writer Thursday, Aug 6, 2009
By MALCOLM RITTER, AP Science Writer Thursday, Aug 6, 2009
NEW YORK – From the goose that laid the golden egg to the race between the tortoise and the hare, Aesop's fables are known for teaching moral lessons rather than literally being true. But a new study says at least one such tale might really have happened.
It's the fable about a thirsty crow. The bird comes across a pitcher with the water level too low for him to reach. The crow raises the water level by dropping stones into the pitcher. (Moral: Little by little does the trick, or in other retellings, necessity is the mother of invention.)
Now, scientists report that some relatives of crows called rooks used the same stone-dropping strategy to get at a floating worm. Results of experiments with three birds were published online Thursday by the journal Current Biology.
Now, scientists report that some relatives of crows called rooks used the same stone-dropping strategy to get at a floating worm. Results of experiments with three birds were published online Thursday by the journal Current Biology.
Rooks, like crows, had already been shown to use tools in previous experiments.
Christopher Bird of Cambridge University and a colleague exposed the rooks to a 6-inch-tall clear plastic tube containing water, with a worm on its surface. The birds used the stone-dropping trick spontaneously and appeared to estimate how many stones they would need. They learned quickly that larger stones work better.
Christopher Bird of Cambridge University and a colleague exposed the rooks to a 6-inch-tall clear plastic tube containing water, with a worm on its surface. The birds used the stone-dropping trick spontaneously and appeared to estimate how many stones they would need. They learned quickly that larger stones work better.
In an accompanying commentary, Alex Taylor and Russell Gray of the University of Auckland in New Zealand noted that in an earlier experiment, the same birds had dropped a single stone into a tube to get food released at the bottom. So maybe they were just following that strategy again when they saw the tube in the new experiment, the scientists suggested.
But Bird's paper argued there's more to it: The rooks dropped multiple stones rather than just one before reaching for the worm, and they reached for it at the top of the tube rather than checking the bottom.
But Bird's paper argued there's more to it: The rooks dropped multiple stones rather than just one before reaching for the worm, and they reached for it at the top of the tube rather than checking the bottom.
The researchers also said Aesop's crow might have actually been a rook, since both kinds of birds were called crows in the past.
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Crows are one of my favorite birds, ever since the day I watched a pair of crows playing in the snow when I lived on the farm. Out my kitchen window I could see the horse pastures. The pasture directly behind my apartment was sloping. There was snow on the ground, and I was enjoying the beautiful scenery when I suddenly realized that there was a method to what the crows were doing. At first it just looked like they were hopping around, but suddenly I saw one crow belly-flop and slide down the slope as if he were sledding. When he stopped, he walked up the slope to belly-flop again and slide down the slope. The companion crow was doing the same thing, and they looked like a couple of kids enjoying a snow day. I was so amazed at what I was observing, I watched until they got bored and flew off to find something else to do. In a later conversation with my friend Sally who is an ornithologist, I learned that crows and other corvids are highly intelligent. I also learned that the Blue Jay is a cousin to the crow.
Here are a few video clips I think you will enjoy that illustrate the intelligence of crows.
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