A New Caledonian crow. Photograph by Vincent J. Musi, National Geographic Creative. In a battle of wits, could a bird outsmart a kindergartner? Don’t be too quick to say no: One clever young bird solved a problem that has stumped 5-year-old children, according to a new study.
The bird—a New Caledonian crow named Kitty—figured out that dropping rocks in one water-filled tube was the key to raising the water level in another, seemingly unconnected tube, giving her access to a floating morsel of meat.
To solve this problem, Kitty needed to decipher a confusing cause-and-effect relationship, basically akin to figuring out that if you flip a switch on the wall, a ceiling light will turn on.
This mental ability was once thought to be restricted to humans, but causal reasoning—the ability to understand cause and effect—has now been identified in a handful of animals, from chimpanzees to rats.
Crows are the Einsteins of the bird world, renowned for their ability to make tools and solve complex puzzles. (Watch a video of a New Caledonian crow solving problems.)
Their impressive mental capacity was even apparent to the ancient Greeks. In one of Aesop’s fables, a thirsty crow is presented with a dilemma when he cannot reach the water at the bottom of a pitcher. He figures out that the water level rises when he drops pebbles into the pitcher, and many pebbles later he is rewarded with a drink.
As it turns out, there’s some truth to this fictional story. A study published earlier this year reported that New Caledonian crows will place rocks in water-filled tubes if they can’t reach a piece of meat that is attached to a floating cork. (See National Geographic’s photos of brainy animals.)
And now a new study, funded by the National Geographic Society/Waitt Grants Program and published July 23 in the journal PLOS ONE, extends that work by showing that crows can solve an even more complicated puzzle, figuring out that dropping rocks in one tube raises the water in another tube.
Of the six birds that took the test, only Kitty—a bird caught in the French territory of New Caledonia (map) and briefly kept captive—passed. Incredibly, she was no more than eight months old when she managed that feat.
Smarter Than Children?
When the study team gave a similar test to 64 people in the 4-to-10 age range, the older children passed with flying colors, but most 4- and 5-year-olds couldn’t figure it out, even after multiple trials.
To be fair, the experimental setup given to crows was slightly different than the one given to children, so it’s not known if younger children would be able to pass the exact same test as Kitty.
More work will be needed to figure that out, said study leader Corina Logan, a biologist at the University of California, Santa Barbara. (See “Crows as Clever as Great Apes, Study Says.”)
Regardless, it’s fair to say that Kitty has some rather impressive cognitive abilities, on par with those of humans much older than herself.
John Marzluff, a crow expert at the University of Washington in Seattle who was not involved in the study, agreed: ”The remarkable success of some crows at solving difficult problems … is very similar to [individual variation in] the performance of humans.
“I would expect some birds to be stars and others to be slower on the uptake, just as I would expect this of children. That this was the case is important and suggests individual variability in attention, learning ability, focus, and skill exists in crows just as it exists in people,” Marzluff noted by email.
Leveling the Playing Field
New Caledonian crows rarely, if ever, encounter the situation described in Aesop’s fable, but the novelty of the task is not a downside—it’s what makes the study valuable, Logan said.
Choosing a task that crows likely won’t experience in the wild “levels the playing field to compare [cognitive abilities] among species,” including humans, she said. (Related: “Fish as Good as College Students in Numbers Test.”)
“It’s a way of getting at what they know about the world and how they solve problems.”
It also goes to show that being called a birdbrain on the playground isn’t such an insult after all.