Study Shows Crows Are as Smart as Seven-Year-Olds
Remember that old Aesop’s fable about the crow and the pitcher? The one in which a desperately thirsty crow figured out that if he dropped enough pebbles into the long-necked pitcher, he could raise the water level high enough to allow him to drink?
Scientists just proved that crows can really do that.
Photo courtesy of Shutterstock
Crows are brilliant birds. Researchers have validated that point over and over again. We know they can make and use tools, conspire together by conveying information to other crows, and remember things like locations where people shot at them years before. They can even remember your face and tell other crows who you are. Think about that one for a while. Don’t anger a crow. She will remember you—and you don’t want that.
Now scientists have proved that crows are about as smart as a seven-year-old kid, in certain contexts. They published their findings in the journal PLOS ONE.
Because it’s not a natural behavior for them, scientists first spent some time training six New Caledonian crows to pick up small rocks and stones and drop them into tubes. The crows’ natural affinity for tool use made this relatively easy.
Then they conducted a series of experiments which children had earlier completed after similar training. The tests done included:
- Water or Sand? A choice between a water-filled tube and a sand-filled tube, to see if the crow could figure out that dropping stones in the water-filled tube raised the water level and gave access to a food reward. Crows nailed this one quickly, some learning within 15 attempts.
- Heavy or Light? A choice between dropping heavy and light stones into the water. The light stones floated, meaning they didn’t help elevate the food into reach. Crows got this one quickly also, choosing heavier stones 88 percent of the time.
- Solid or Hollow? A choice between solid or hollow objects. Hollow objects were lighter, of course, and so less helpful in getting to the food. Crows chose solid objects 89 percent of the time.
- Narrow or Wide Tube? This test was the crows’ downfall. They didn’t catch on that dropping things into the narrower tube raised the water level faster than the wider tube. They only chose the narrow tube 39 percent of the time.
- Narrow Tube with Too Little Water. Here, crows got a tube with a water level that was too low to ever get high enough to give them their treat, no matter how many stones they used. The crows latched on to this trick pretty quickly. They put their stones in the other tube with more water 86.6 percent of the time.
- Three Tubes, One Too Small. This test was another poser that the crows didn’t get. Of three tubes, a middle one held the treat, but was too small for any stone to drop in. One of the other two tubes was connected to the small tube, but the crows didn’t realize putting stone in that one would get them their treat. Oh well.
Successful completion of four of six of these tasks, according to the research team, means crows have a basic but definite understanding of causal relationships.
The study concluded that, “New Caledonian crows possess a sophisticated, but incomplete, understanding of the causal properties of displacement, rivalling that of five–seven year old children.”
That’s rather impressive, isn’t it? Sorry, pretty songbirds. Crows have the Avian Awesomeness category all wrapped up.
Unfortunately, even though they’re the smartypants of the bird world, we give short shrift to crows.
“People tend not to like crows, because they have this fiendish look to them and they’re black and they like dead prey,” Dr. Louis Lefebvre of McGill University told the BBC. “Warblers and the birds that people tend to like are not the high innovators.”
Maybe that’s why people participate in sad and ridiculous events like New York’s “Crow Down.” Why is there any joy associated with killing a crow, or any animal for that matter?
Time and again, researchers demonstrate that animals are so much more intelligent than we give them credit for. Whether they’re elephants that use teamwork to solve problems, pigs that can play video games with a joy stick, dolphins that teach tricks to each other, chimpanzees that can beat humans in short-term memory tests, or crows that can solve causal relationship problems, there’s an astounding abundance of savvy animal activity going on all around us.
Why then do we continue to hunt them, harass them, destroy their habitat and otherwise harm them? We do it because we can, but not because it’s right. Perhaps we’re learning—slowly—that we share this earth with other animals. They have as much right to live here in peace as we do. Can’t we just let them do that?
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