Crows show off their smarts
"What the crows have done is a phenomenal feat," says Ed Wasserman, a University of Iowa psychology professor and corresponding author of the study. "That's the marvel of the results. It's been done before with apes and monkeys, but now we're dealing with a bird; but not just any bird, a bird with a brain as special to birds as the brain of an ape is special to mammals."
"Crows spontaneously exhibit analogical reasoning," was published in Current Biology. The Russian experiment involved two hooded crows that were at least two years old. In phase one of the experiment, they were presented with three small cups each covered with a card showing two coloured shapes. The middle cup was the sample cup. The crows were trained to recognise that when one of the cups on either side of it carried a card that matched the sample cup card they would find two worms inside.
In phase two of the experiment, the card concealing the worms did not precisely match the sample cup card, but bore a relationship to it. For example, the card concealing the worms might show two same-sized circles, when the sample card displayed two same-sized squares.
"That is the crux of the discovery," said Wasserman. "Honestly, if it was only by brute force that the crows showed this learning, then it would have been an impressive result. But this feat was spontaneous."
Anthony Wright, neurobiology and anatomy professor at the University of Texas-Houston Medical School agrees. "For decades such reasoning has been thought to be limited to humans and some great apes. The apparent spontaneity of this finding makes it all the more remarkable."