25 November 2014
Intelligence was once supposed to be simple. Brain size equaled intelligence. But, then, there wereissues. Some animals, with smaller brains, seemed to be smarter than some animals with larger brains. So, maybe it was the structure – the way the brain was built. So, could intelligence be found only in brains with a “neocortex?” Human beings and apes (primates) have brains with a neocortex. Maybe that’s what made them so smart?
Intelligence was once supposed to be simple. Brain size equaled intelligence. But, then, there wereissues. Some animals, with smaller brains, seemed to be smarter than some animals with larger brains. So, maybe it was the structure – the way the brain was built. So, could intelligence be found only in brains with a “neocortex?” Human beings and apes (primates) have brains with a neocortex. Maybe that’s what made them so smart?
Or maybe it wasn’t.
It came as a surprise when the great apes got nosed out (or should I say, “beaked” out) of their position on the intelligence ladder by a family of birds, the corvids.
Who are the corvids?
You know some of them as blackbirds, crows and ravens. You know! Those dark colored birds that, over the past few centuries, have developed a rather “dark” reputation. Often used as props in Gothic horror films and stories, in some circles, these birds are even believed to be omens of death.
In spite of the “funeral” overtones of their reputation, the corvids themselves are thriving. In fact, they are one of the few groups of birds on earth whose populations are increasing. Maybe this is because they like to hang-out with another species whose populations are increasing . . . us.
Corvids are more scavengers than predators, and human society provides them with abundant supplies of exotic foods. We, also, probably provide them with entertainment because, in fact, they watch us more closely than we’ve ever watched them. And, certainly, they remember more of what they see of us than we do of them.
As disturbing as it sounds, if you live in a neighborhood with a large corvid population, they know who you are. Not just that you’re a human being. They know and recognize you. They, also, know where you live.
To explain the avalanche of evidence of the high intelligence of these birds, a new theory has been “floated.” Intelligence isn’t about brain size or structure. Maybe intelligence is brain to body ratio. That is, brain size compared to body size. With that formula, the corvid’s walnut-sized brain is bigger in relation to its body than are the brains of any of the great apes. And maybe this new formula will make sense of it all. Because testing corvid intelligence produced some strange results.
Why?
Because these birds are smarter than any of the great apes. In fact, if your children are around 5 or 6 years old, in terms of intelligence, they’ve been edged out by the neighborhood crows. Corvid intelligence is roughly comparable to about a 7 year old human child. And, if you’ve ever lived with a 7 year old human child, this should make you just a little nervous.
But before we go too much farther, we’ve left some corvids out. All these birds aren’t the black birds with “Grim Reaper” associations. The bright colored blue jay and two-toned magpie are also corvids. As a matter of fact, the magpie was the first of the group to attract a lot of attention.
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Corvids live in clearly defined social groups during the period in which they raise their young. In fact, if corvids could speak, they probably would have been the first to coin the African proverb -- “it takes a village to raise a child” because young corvids are raised, strictly, within a defined community.
When observing one of these communities of magpies, researchers noted how aware these birds were of their fellow magpies. This awareness is described by the term empathy. And the corvids have a good grasp not only of their fellow birds as individuals but, also, what their fellow birds might be thinking.
Magpie
These birds often gather food and hide it for a later meal. If they see another bird watching them hide their food, they don’t “let on.” Instead, they finish the job, hide and watch the bird that was watching them. If the bird swoops in and tries to steal their hidden meal, the corvid will attack and defend its hidden treasure. But, if the other bird moves out of sight, the corvid will immediately swoop back in, retrieve its hidden food, and hide it elsewhere – making sure that, this time, it is unobserved.
But corvid intelligence goes far, far beyond this kind of behavior. And to demonstrate (and get to the point), let’s go fishing on the Pacific island of New Caledonia!
Russell Gray and a group from the psychology department of the University of Auckland in New Zealand were observing New Caledonean crows. The crows probably got tired of observing this group of human beings who were observing them, and decided to squeeze in some fishing. Unlike humans, who have to haul their tackle box around with them, the crows “rough-it” and make their equipment from scratch.
The crows quickly grabbed tree branches, stripped them of side branches, and formed the ends into hooks. These birds particularly like to eat a type of grub that lives in narrow nooks and crannies in the rocks. To get an even quicker snack some of the birds picked up leaves and stripped off the leafy part to get a long, thin probe covered with short barbs. This was the perfect tool to use extracting grubs.
Crow Fashioning a New Tool
And these birds aren’t lazy. Sometimes, it’s quicker to make something from scratch than to go looking for an ideal finished product. “Betty,” a New Caledonean crow was captured and tested by the ecology group at UK’s Oxford University. The group’s leader, Alex Kacelnik, explained that the group discovered that the year and a half old bird could do some surprising things.
When a bucket of food was placed in a well, Betty was presented with straight and hooked pieces of wire to test whether she would pick the hooked wire and use it to retrieve the bucket and pull it up out of the well.
Sometimes, she did, but if a straight piece of wire was closest, Betty just picked it up, bent it into a hook with her beak, and retrieved the bucket from the well. With strips of different lengths she, just as quickly, bent to strips to the correct length and, then, bent the ends into a hooks and retrieved the bucket. Adding strips made of different, more or less pliable, material made little difference. Betty quickly fashioned the perfect tool and retrieved the bucket.
But where could Betty have learned all this? Well, Jenny Holzhaider at the University Auckland wanted to find out and, so, followed some of the crows home. And, of course, discovered the secret crow “tool school.”
Actually, there is a kind of crow school, and it is a kind of secret. Most corvids raise their young as part of a close-knit community. But New Caledonian crows are less community oriented. But what they lose in community, they gain in family. These birds raise their young in close-knit family groups. The adult crows welcome the presence of their children as the adults engage in all sorts of daily activities. The young birds accompany their parents to locations in which the parents use their tools. Not only do the young birds observe their parents making tools, but are allowed to use the tools made by their parents. The young birds spend two years with their parents during the learning process.
This is certainly a school. But is it secret? Secret, only in the sense that the entire process takes place within the family unit. Human artisans have long trained, and continue to train, their children and selected apprentices in particular skills. The crows on New Caledonia seem to do the same thing. You have to wonder if all crow families are equal in all skills. Maybe, some particular refinements and techniques are more developed in some crow families than in others. The crows understand their skills and, keeping their instruction in the family, carefully impart these skills to their young.
Professorial Crow Probably Lecturing to Students about Human Intelligence
Dr. Gavin Hunt, also of the University of Auckland, notes that the New Caledonian crow’s abilities are learned, not within a community, but through a small number of “high quality relationships.”
Is there more? Christian Rutz, of Oxford's behavioural ecology group, believes that we are only at the beginning of learning about crows and far from answering all the questions about the intelligence of these avian fishing-birds.
Mark Grossmann of Hazelwood, Missouri & Belleville, Illinois
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