Crows are special. They make tools from memory, and they even gather around their dead. And the list of what makes them special gets longer every day. Research published on Wednesday in the journal Proceedings of the Royal Society B suggests that New Caledonian crows, a species from the South Pacific, can infer the weight of an object just by watching it blow in the wind. This finding makes New Caledonian crows the only known animal species — besides humans — that can make these judgments without physically interacting with the objects.
In the new paper, a team of researchers outlined a series of experiments in which they found that crows could tell, just by watching two boxes get blown around by an electric fan, which box contained the heavier object. This type of inference may seem logical to humans — a candy bar caught in an updraft, for instance, is obviously lightweight, while a coconut falling from a tree is clearly heavy. Among non-human animals, though, this type of perceptive ability is actually quite rare. Even chimpanzees, who share 98.8 percent of their DNA with humans, have been unable to infer the weight of objects in experiments. But Sarah Jelbert, Ph.D., a post-doctoral research associate in the Department of Psychology at the University of Cambridge and the paper’s first author, says the ability comes quite naturally to crows.Read More... Stunningly Clever Crows Correctly Completed a Task That Only Humans Can Do