Being another Excerpt in the Ongoing Spectacle that is The Beowulf Effect: Fossils, Evolution and the Human Condition, a book currently being written for the University of Chicago Press and is now more than a month overdue. But I am near the end, now, so while you’re waiting here’s a little something on the intelligence of crows.
The cleverness of crows is proverbial. Everyone must have seen, by now, videos showing how crows leave nuts in roads, waiting for them to be cracked by the wheels of passing traffic – and the trick of those especially clever crows that leave nuts on pedestrian crossings, allowing the crows to retrieve the spoils without getting run over. In her lab, Nicky Clayton of the University of Cambridge showed me a video showing how, when a crow is confronted with a morsel floating in a beaker of water but too deep for it to reach, the bird will use stones nearby to displace the water, raising the morsel to the surface and allowing it to be reached. To do this, the crow had to be able to appreciate the various properties of materials, such that the food scrap floated, even when stones were thrown in the water; that stones would fall to the bottom; that stones displaced the water (equivalent to Archimedes’ ‘Eureka’ moment); that the water would rise up the beaker, carrying the morsel of food. Not only that, the bird would have had some concept of itself throwing the stones into the water to achieve the desired outcome.
To me, the most remarkable fact about crows is that theirs is a kind of intelligence that we can recognize — the calculation and the craftiness are things we see in ourselves. If this is true, it is remarkable, because crows and humans have brains that evolved entirely separately, along completely distinct pathways. The common ancestor of crows and humans was some kind of reptile that lived more than 250 million years ago, and would not have enough brains to write home about. As a result, the human brain – and that of other mammals such as primates, dogs, whales and horses and so on – is made entirely differently from that of crows.
This is an important insight in the context of this book because, once grasped, it shoots a huge hole in the idea that what we think of as the human mind must necessarily have evolved from earlier hominins simply by virtue of the fact that they were hominins, and had an evolutionary heritage that would have demanded progressive cognitive improvement in that lineage alone. It forces us to look at what we and crows have in common, to the exclusion of apes – and, from that, helps us understand the evolution of intelligence in general terms, not just in our own evolutionary lineage. All such similarities must necessarily be concerned with behaviour rather than anatomy, as human brains and crow brains are wired differently, and crows don’t have the hand-eye coordination popularly thought of as having been instrumental in the evolution of the human mind.
What humans and crows (and many other birds) have in common is an active social life. Unlike apes, which are solitary or live in small groups, humans and birds tend to live together in large groups in which relatives of various ages mix together with less familiar individuals. They tend to learn from one another, but they are also competitive. Human and bird societies are cohesive and complex, and prone a certain amount of internal discord and deceit. There’s is no doubt that the minds of crows are not only comparable in capability with those of humans, and have much the same flavor, for all that crows have no language, no hands, and brains the size of berries. A short visit to Clayton’s lab should dispel any notion that intelligence is necessarily all about brain size or hand-eye coordination. That we can recognise the same phenomena in creatures as distantly related to us as crows, suggests that what we think of as intelligence might have less to do with the physical structure of brains in isolation, but in the complexities of social relationships quite irrespective of form. If we find intelligent aliens, we’ll recognise them, too. They’ll behave just like we do.