Raven vending skills redefines intelligence

A small island in the South Pacific is home to a raven with remarkable abilities that attract scientists.

Caledonian crows make and use tools – including a kind of hook.

They can solve complex problems and have even been recorded catching larvae by repeatedly pricking them with a stick until they are restless, they bite.

Now, an experiment using a vending machine how intelligence evolves.

The "sales experience" is the latest in an ongoing investigation into the abilities of these birds. They are so remarkable that scientists have a special aviary in New Caledonia, where they can keep wild birds for only a few days and test their problem-solving prowess before releasing them into the forest.

How do you design a crows vending machine on Earth?

It's actually a cleverly designed intelligence test. Dr. Sarah Jelbert, of Cambridge University, who developed it, explained that to immerse herself in the cognitive abilities of birds, she had to see them learn something new. So, the idea was to create a different task than what crows would find in nature.

"They would obviously never find paper or cards in nature," says Dr. Jelbert, "so we developed this vending machine in which they could put small pieces of paper to release a small piece of meat. "

First, the birds must be" convinced "to use this box-shaped machine. "We put stones or pieces of paper on top of the box with meat hidden underneath," says Dr. Jelbert. "The birds often push the stone or paper into the hole, or slot – which triggers a reward from the vending machine."

Once the birds learned how the machine worked, the team gave them a piece of paper too big to enter the slot – to see if they could cut into smaller pieces that would go. "About half of them did it spontaneously," said Dr. Jelbert.

Up to now, everything is fine. But that's where the test gets complicated – and revealing.

For their study, which was published in the journal Nature Scientific Reports, scientists really wanted to know if birds could make the right size a "paper token" of memory. According to Dr. Jelbert, this could be the cliché that she wanted that explains how wild birds have learned to craft complex and artisanal tools – like those hooks that they make to catch white grubs.

This, she explained, was an investigation into how these birds might develop "their own culture of tool-making".

Thus, the researchers provided each of eight crows with a vending machine that would release a treat only when a particular size of paper was inserted.

"So," Dr. Jelbert explained, "we tested if they could remember the size that worked, and if they would do it themselves." The birds did not have a template – they just had to remember the size of the paper token required by their vending machine.

Dr. Jelbert added, "And we found that all adult birds spontaneously made the right piece of card for their vending machine."

Very intelligent. But what does it tell us about it?

Scientists who have studied these birds for years say that they have already revealed the very early stages of innovation.

From his own perspective on the abilities of animals, Professor Christian Rutz, of the University of St Andrews, said: When I see these crows doing hung tools, I have a glimpse the very foundations of a changing technology. "

And Dr. Jelbert said the birds revealed that there could be "many different ways that evolution can produce intelligent behavior."

"Because we humans give priority in imitation of others, to other animals. "

But Dr. Jelbert explained that birds do not seem to care or copy the behavior of others in the same way that a human child could copy a teacher or parent.

" But we see Minors rob an adult And if crows remember that a specific tool has worked and recreated it from memory, this could show how a culture of using tools can be prevalent in a population of birds. "

Why is it important?

Researchers continue to be impressed by the capabilities of these birds, but they are not only entertaining and inventive in toolmaking and problem solving, they also show us how well they are. intelligence can evolve. very different way of how it has evolved in humans.

"With crows, we see behaviors very similar to human behavior – even if they only have a beak and feet, they can manipulate things and make tools quite complex," said Dr. Jelbert . we that our path is not the only way and I find it quite humiliating. "

Follow Victoria on Twitter