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These birds have all the brains.
It’s well known that ravens, crows, and other members of the corvid family are more brainbox than birdbrain. But scientists continue to be astounded by just how clever these avian Einsteins prove to be.
One recent study claims that by four months old, ravens have full-blown cognitive skills and before reaching full maturity they can rival adult great apes. Another, indicates that problem-solving crows perform similarly to children under seven years of age. And what is more remarkable is the scope of intelligence that these feathered masterminds display…
Many animals undertake tasks that aid their future welfare, such as beavers and squirrels storing food to eat when resources are scarce. But no animals, other than humans and possibly some apes, were thought to forward-plan and map out a number of possible future outcomes. But it was proved for the first time that ravens had planning capabilities. In one experiment, they were trained to return a token in exchange for a food reward, before then having to choose between several items, including a low-quality snack and one of the tokens. 73 per cent of the time, the birds picked the token, assuming that better food would be provided, rather than grab the food in front of them.
While corvids cleverly remember experiences that enhance their lives, such as in the experiment just mentioned, their feats of memory go way beyond this. As biologist John Marzluff recorded that crows can hold a grudge. He discovered the birds remembered his face and didn’t enjoy being caught and tagged by him. Not only that, they told other crows about this human troublemaker by signalling danger when he appeared, so they resented him too and acted aggressively towards him.
But crows also remember the good times. Researchers revealed that ravens were able to remember a human who cheated them out of a snack and were also more positive towards humans who exhibited fairer behaviour.
It’s well documented that corvids can use tools to obtain food, but also use sticks to carry more than one item at once. Remarkably their tool use is even more involved: they found crows understand the science of water displacement, being able to add items to tubes containing liquid to secure a treat. But even more remarkably, research has also shown that corvids can make tools, as well as use them. Video evidence has been shared, showing crows stripping bark from a twig and fashioning a hook, which they used to prize hard-to-reach food from crevices.
Crows and other corvids aren’t just great at using their memories, fashioning tools, and making plans, they can throw all of these skills together to figure out complex puzzles. One genius bird, dubbed 007, was able to successfully complete eight separate stages of a puzzle – in the correct order – using tools such as stones and sticks. And a separate experiment indicated that while it took some birds longer to figure out the solution to his particular puzzle, they all figured it out in the end. Amazing!