Animal IQ

Ravens Can Plan Ahead Just As Well As Apes

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You've probably heard that ravens are smart. In the lab, they've been able to perform some surprisingly complex tasks for food, and as pets, they can mimic human speech just as well as a parrot. Now, research shows they're probably even smarter than you realize. When it comes to planning ahead, ravens perform as well as — and in some cases better than — apes, one of humanity's closest relatives. Is it time to prepare for the raven uprising?

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A Raven Never Forgets

Ravens are part of the corvid family, which includes other birds like crows, jays, magpies, and nutcrackers. All of these birds have proven to have some wicked smarts. Crows can remember your face for years, and nutcrackers can remember thousands of different places they've hidden food (we'd certainly have trouble doing the same thing).

Ravens, for their part, have proven they can easily retrieve a treat on a string on their first try, even though it required a series of complex steps. They've also pushed rocks on biologists to keep them from climbing up to their nests, and played dead beside beaver carcasses to scare off other birds from their meal.

In a July 2017 study published in Science, researchers show that ravens can also plan ahead — an ability previously only seen in humans and great apes. For their first experiment, they trained ravens to use a tool to open a puzzle box, where they found a food reward. Next, they presented the ravens with the box, but no tool, and left it in the cage for a while before removing it. An hour later, they again presented the raven with the tool, along with other miscellaneous objects. Even though the box was out of sight, nearly every raven chose the correct tool, then successfully opened the puzzle box when it returned 15 minutes later. That is on par with what apes can do, even though ravens don't have a primate's dexterity for tools.

Next, the researchers performed two experiments involving bartering and anticipation. When they gave ravens a token that they could later use to barter for a reward, they were actually more accurate in their planning for the barter than apes have been. In the anticipation experiment, they gave ravens a series of objects that include the box-opening tool, miscellaneous items, and an immediate reward. The researchers allowed the ravens to select only one object. Overall, ravens preferred the box-opening tool because it meant they got the reward in the box. That demonstrates a level of self control that rivals that of apes. (It certainly rivals ours, anyway.)

Avians And Apes, Apples And Oranges

When scientists see primate species perform complex tasks that were once thought unique to humans, it makes some sense. We evolved along the same lines, and share a relatively recent ancestor, so our brains share many similarities. But while the last common ancestor between humans and great apes lived about seven million years ago, ravens and great apes haven't shared a common ancestor in more than 300 million years. That suggests that these advanced feats of brain power evolved separately, once in apes, and once in birds.

It also could mean that our understanding of bird brains is just beginning. For instance, we've always believed that in order to recognize yourself in a mirror, your brain needs a neocortex, that top layer of wrinkly tissue that makes up three quarters of the human brain and is unique to mammal species. But magpies still recognize themselves in a mirror, neocortex be damned. If birds evolved higher-level thinking independently from our primate ancestors, judging their smarts from how much their brains look like ours may be as misguided as judging a cheetah's speed from how fast it can swim. When it comes to avian intelligence, human researchers might be the bird brains.

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