The all-knowing, Old Norse god, Odin, was probably just a big couch potato, for he had two ravens, Huginn (“Thought”) and Muninn (“Mind”) who flew the land of man each day and reported back to him at sunrise. More than any other birds, the members of the Corvid family—note the “r” (we’ve probably heard quite enough of COVID)—particularly crows and ravens, are embodied in the mythology and folklore of many cultures. Though sometimes they are regarded as harbingers of death and bad luck, the familiars of witches or as tricksters, on balance, they are much more frequently associated with wisdom, the gods and creation. Several Native American tribes regard them as good luck and attribute prophecy and insight to them. The birds often figure in heraldry. It is said that after St. Vincent of Saragossa died from torture in 304 CE, ravens guarded his body (and later his tomb) from predators until he was reburied in Lisbon, Portugal; ravens appear on Lisbon’s coat of arms today. There are ravens at the Tower of London, and the legend was that if they ever left, the British Empire would fall. By the end of the second World War, many had died from the bombing, and the remaining two departed. Was it a coincidence the Empire began to fragment and dissolve afterward? In 1946, six pairs were brought back to the Tower with clipped wings.

Crows or ravens figure in the mythology of the Hindus, Greeks, Celts, tribes of the Pacific Northwest, and the Australian aborigines. There is the fable of The Crow and the Pitcher, written by Aesop, an ex-Greek slave in the mid-sixth century BCE.1 The ability of crows to perform what is recounted in the fable has been confirmed in experiments by modern era researchers. Neglecting the supernatural associations, the common thread of all these myths and legends is the intelligence of the birds.

Quite apart from myths, there is a wealth of anecdotal evidence that lends credence to a level of intelligence. Magpies (another member of the Corvidae) have a liking for bright objects. One year, at the Evergreen Artists Association Fine Arts Festival, I witnessed a magpie take a nickel from an artist’s shoe, fly away, and return with a wisp of straw that it inserted into the shoe in place of the nickel. In another instance recounted by a relative, a construction worker used a very old pickup that had a lot of shiny knobs on the controls, but lacked doors. During one contract, the knobs began to disappear, and after a while, the cab began to smell very bad. The client had been feeding the local magpie on hamburger and it had been removing the knobs and substituting hamburger pushed into crevices in the cab. The example of exchange in these cases is intriguing; what motivated the birds to feel an exchange was necessary?

It’s about 20 years since New Caledonian crows were first observed using “tools” (hooked twigs that they themselves make to pry food from holes in trees), and since then, aside from the anecdotal evidence, a great deal of detailed research has been directed at investigating the cognitive and problem-solving ability of birds, especially members of the Corvidae family—ravens, crows, magpies, nutcrackers, jackdaws, rooks and jays—but also with parrots and pigeons. The published results show that they demonstrate “complex cognition, including causal reasoning, mental flexibility, planning, social cognition, and imagination.” On the negative side, one might also add the abilities of deviousness, dissembling and vocal impersonation. The birds can recognize their own images and the “voices” of their kin; they can use a tool to manipulate a second tool to achieve a desired result. Some crows in Japan drop nuts on roads for cars to crack, and can recognize and respond to changing traffic lights;2 the list becomes endless. Researchers developed ingenious tests to reveal and study these abilities, but there are far too many to describe here. Suffice it to say that the intelligence of crows and ravens is now accepted as rivaling that of chimpanzees and 6- to 7-year-old humans. How can that be so?

Reasoning in humans takes place in the cerebral cortex, just inside the forehead, but the brains of birds are organized in a totally different way to our own. The most recent research seems to indicate that the need for cognition in the same set of environmental conditions has caused evolution to develop essentially the same wiring diagram for differently organized brains (similar mental functions require similar neuronal networks).

In their own way, the more intelligent birds seem to exhibit some features of intelligence in common with primates, though other behavior that is undoubtedly valid in the bird’s world remains opaque to us. The rook is a Eurasian member of the Corvidae and is almost indistinguishable from a crow, except that they are gregarious and congregate in large groups called rookeries. In a high wind, I have often seen them leave a rookery and fly all together, chasing tails, jinking and weaving, somersaulting and executing aerobatics in the tumbling, gusty air. It is hard to doubt they are playing and/or exhibiting their flying skills. Some researchers have theorized this is a way juveniles can show off their abilities as potential mates—not so different from human teenagers. It is not beyond the possibility that play is just as important for intelligent birds as it is for human children.3,4

None of this really explains how the much smaller brain of a bird can match the cognitive skills of primates with much larger brains. It is an area of current research, but it has been shown that corvids (and parrots) pack twice as many neurons into important areas of their brains than might be expected for their brain size. Even pigeons have been shown to have faster reactions than humans on particular cognitive tasks. One way computers have become faster is for ever more connectivity to be concentrated on the processor chips, shortening the connection distances between parts. Perhaps this is part of the answer. Just as bipedalism may have encouraged the development of human brains (see April issue), perhaps flying and the instant reactions necessary dictated the need for densely packed, rapidly communicating neurons in the brains of birds. Mammals developed cognition by expanding brain size to accommodate more neurons. The current theory is that birds did so by upping neuron density.

Mammals and birds, two very different organisms, have existed for millennia in parallel environmental niches. Though their brains are structurally very dissimilar and differ so much in size, it is increasingly apparent that evolution has driven the development of a pattern of neuronal connectivity that is remarkably alike, producing the cognitive skills necessary for survival. This is an example of convergent evolution.

 

References:

  1. Aesop’s fable: “The Crow and the Pitcher:” bit.ly/3da9e7m
  2. PBS article, including crows cracking nuts in Japan: to.pbs.org/2TPzEU9
  3. Examples of play, perhaps: bit.ly/3gyH2Nm and following.
  4. February, March and April issues of Serenity.

© David Cuin 2020