Corvus (15 page)

I tell people constantly about the intelligence of corvids. I agree when anyone says that they've heard corvids are meant to be intelligent. I've read, observed, believe I know, but do I? How do I know? I haven't done any tests that might prove it, but then I haven't on most people either (or, in fact, on anyone at all), but this doesn't prevent me from forming opinions on the nature or capacity of their intelligence. What I think about people, a matter equally untested, is based on a set of undefined criteria which I recognise but may be different from others pondering the same questions. There is, of course, a comparative basis to any belief about intelligence as much for humans as for birds. I think, much as I might of people, that certain birds I know are intelligent, and some less so. I think the corvids I have encountered are
intelligent but how do I know? I base my view on many things: what they do, how they respond, their ability to recognise, their ways of behaving, but on other things too, things untested and possibly untestable, demeanour, curiosity, response. When I read in
In the
Company of Crows and Ravens
that magpies are able to recognise themselves in a mirror, an indication of high degree of self-awareness, I wasn't surprised. When a red light is shone onto the white feathers of a magpie as it looks at itself in a mirror, it will begin to try to remove the stain of red. The higher primates and elephants have also demonstrated this quality of consciousness of self.

Some birds appear to be more intelligent than others. Many of the conclusions about comparative bird intelligence have been drawn from observation. Dr Louis Lefebvre from McGill University has designed a system of testing bird intelligence by relating it to reports of innovative behaviour, much of it feeding behaviour, collated from observations made over decades by individuals or published in scientific journals. Lefebvre's method avoids some of the known difficulties of intelligence studies: cultural bias, as well as the use of equipment (which is problematic in studying bird intelligence, because, as many researchers have pointed out, equipment and testing devices of one sort and another are what people do, not birds). According to Lefebvre's study, the cleverest birds (need I say) are corvids, followed by falcons, hawks and woodpeckers. (The question of comparative intelligence may be invidious. Does it matter if one bird or beast is more intelligent than another? The wider significance, or usefulness, may be in the alteration of attitudes, if greater awareness of the capacities
of all birds and animals leads to more considered treatment of them.)

There's abundant evidence to show that for a long time and in many different cultures people have recognised, or at least suspected, that corvids are clever, but it's only now, when close scientific examination of the physical properties of corvid brains and extensive study of their behaviour can be carried out, that it's possible to gain appropriate insight into the true magnitude of their abilities.

Corvids are among the birds that have the highest encephalization, or brain: body ratio. Their nidopallium, the avian brain structure that fulfils broadly the same functions as the mammalian neocortex, that of sensory processing, is larger in the corvid than in most other birds except parrots, the other avian group deemed by legend and hearsay to be particularly clever. Corvid brains are relatively the same size as those of apes and indeed Dr Nathan J. Emery, a neuropsychologist in Cambridge's Department of Zoology, suggests that in their cognitive ability corvids rival the great apes and might well be considered ‘feathered apes', many aspects of both the biology and behaviour of these two disparate species, in spite of differences in their brain structures, being remarkably similar as a result of the processes of ‘convergent evolution' (whereby unrelated organisms, affected by the same environmental circumstances, evolve similar traits). Corvids, like apes, have evolved within large social groups, which by virtue of their complexity and their requirements, their demand for mutual recognition, negotiation and communication, seem to encourage and stimulate intellectual development.

a smooth shell of grey and parchment bone

As a result of their extensive work with both, Dr Emery and his colleague Dr Nicky Clayton suggest that apes and corvids share a number of abilities that contribute to their high level of cognition, including the understanding of cause and effect, and the ability to think about things that aren't present, to apply previous learning to new situations, and to think about the future.

One aspect of behaviour shared by all the birds suggested by Louis Lefebvre's study to be the most intelligent – corvids, falcons, hawks and woodpeckers – is that they are all birds that cache. Caching, which in corvids is part of life in a social group, a bit like lying, requires a prodigious memory, the kind of memory that is accompanied by, and the result of, owning a sizeable brain.

To cache, a bird must be able to remember where its (often unimaginably) large numbers of cache sites are located. It needs the spatial awareness to be able to find its cache sites again. In addition, birds may have to have what is called ‘theory of mind', the ability to consider the mental processes of another, which in this case involves being master of a range of stratagems of Byzantine complexity in order to deal with the theft and duplicity that seem to be integral to caching behaviour. Birds have to be observant, vigilant, sneaky, possibly dishonest, and, more than all this, they have to be able to anticipate that their fellow cachers are likely to be just as prone to these unfortunate tendencies as themselves. Stealing from other birds' caches is common. Birds who know that they have been watched in the act of caching will return later when unobserved to remove and rehide their store. Interestingly, it's only those who themselves who have been thieves in the past who
will do this, indicating that they have the ability both to remember and to ascribe motive.

Not all birds, of course, are as intelligent as corvids appear to be. From long observation, I've always thought doves and pigeons considerably less bright than the corvids of my acquaintance (and indeed it seems likely that they possess a smaller nidopallium than corvids), but a piece of innovatory research carried out at Keio University in Japan demonstrated that, with suitable training, they can tell the difference between paintings by Picasso or Monet, Braque or Delacroix. The training, I'm sure, can't have been easy, even though food rewards were involved. I have noticed no particular sign of highly developed aesthetic appreciation in my doves but I'm sure that it's only because I have denied them the correct opportunities to display it. (Might an auction house be interested in this singular skill? ‘I say, that's a nice Bonnard!' ‘You're not trying to tell me that's a Watteau!') For their efforts, the three researchers who carried out the project were awarded the 1995 Ig Nobel prize, a prize awarded annually for research that ‘first makes people laugh and then makes them think', by the scientific magazine
Annals of Improbable Research
at a ceremony in Harvard's Sanders Theater.

I don't find it difficult to believe that some birds have the capacity to do what might be described as thinking. Observing in my own birds what seems like a process of consideration, followed by an action, perhaps a choice of one from among a series of possible actions, allows me to believe that it has been thought of one sort or another that has brought about that particular choice. It was the observation of his
behaviour that allowed me to think that Spike was intelligent, more intelligent than any of the other birds I have met. When he balanced an object – a pamphlet, a rubber glove, a matchbox – carefully on top of a half-open cupboard door, as he did frequently, watching, waiting until it fell onto the head of the next person to open the cupboard, was that behaviour a result of thought? When he tried to fly with his chopstick, laying it down to check the point of balance before lifting it? Possibly.

We used to see Chicken hiding things in the garden, worms, small stones, pinning a leaf over them with a twig to hide them and keep them in place. I watch Chicken caching. She now knows the texture of things, what will stick to what, what is best cached in a place where stickiness is or is not required. I have seen her smooth out paper so that it will fit between the lathes of the wall. Had I thought of it earlier, I might have tried to teach them Greek and Latin.

I don't want birds to be other than they are. I don't believe that they understand every word I say, the dictum beloved of animal lovers, pet owners everywhere, which means, in fact, that they understand intonation, expression and body language. Chicken understands a great deal – gesture, tone, inflection and, I'm certain, many words – but some words she doesn't, as I may not fully understand some words of hers. By now, I don't worry about it. We make ourselves understood.

According to the behaviourists, it is impossible not only to make judgements about the emotional lives of birds, but to countenance, without strict and sufficient evidence, that they have feelings or emotions at all. The cognitive ethologists are more accommodating. I
relate it to my own experience. How else can I interpret frank displays of outrageous fury, the hissing and feather-raising of the enraged bird? What else are the displays of anger and frank dislike Bardie feels for me, and equally, the pleasure, affection, indeed love, he shows for Bec? If it wasn't rage that made Icarus shout in apparent irritation at Bardie and bite his feet, what was it? Why, if we are not all subject to at least some of the same emotions, are they so recognisable? (Do I just wish it to be so?) Why, if we all live in situations of complex social organisation, should we have emotion and they not? If they are capable of anger, might they not be capable of affection? Whilst it may be easy for humans to apply values, insights, moralities that may or may not justifiably be applied to animals, that does not, clearly, necessarily suggest that tenderness, kindness and care for others do not exist in any but human society.

I use the words of human emotion to describe bird emotions, for I know no other ones, only passion and anger, delight and love and grief. There are plenty of incidences of the observation of grief in animals, although judging the mental processes impelling their behaviour is difficult, if not impossible. I have, though, seen what looks like grief in doves, watched their sinking, bowing into postures of abject despondency on the death of mates. It looks remarkably similar to grief in humans. I have seen – or believe I have seen – in birds impatience, frustration, anxiety in the urge to impart news, affection, fear, amusement (the last being a difficult one, I admit, to prove, merely on the basis of watching the look on a magpie's face as its booby-trap was successful) and, particularly, joy. I may be wrong in my interpretation,
inexorably skewed in my judgement by the effects of long exposure to anthropomorphic ideas, but I believe that I recognise all of them because they too look remarkably similar to their human equivalent.

Some corvid young remain with their parents, ‘helping' to rear the next clutch of young, but ‘help' is a word that suggests intent, and for some biologists is therefore a word misapplied. Why should birds ‘help' one another when the sole imperative in the lives of birds is meant to be the self-interest of genes, reproduction at any price, anything more than the urge to procreate and to survive being superfluous, unlikely or impossible? Crows have been observed engaging in behaviour that would have no reproductive value – feeding other ill or injured crows, taking care of orphaned young – and while it may be that such behaviour strengthens social and family bonds, encourages mutual defence and eases the processes of further reproduction, that may not be as different as we would like to think from our own behaviour and underlying motivations when we engage in similar acts. Studies involving egg-swapping among corvid populations with observably different social customs have demonstrated that cooperative behaviour is learnt, rather than innate. Those who have studied pair-bonding among birds, such as Bernd Heinrich, have concluded that birds ‘fall in love' (as would seem appropriate enough where, in general, lifelong monogamy is the social norm).

The concept of empathy in non-humans is also questioned. Recently, a vet writing in an American veterinary journal suggested that whilst animals sometimes respond to their owner's distress, their response should not be interpreted as their ‘experiencing the emotion
of empathy'. Really? I have frequently experienced responses from both Spike and Chicken that I can describe or interpret only as empathetic. I may be wrong, too anxious to see them as capable of such emotional range, but to have a magpie, on seeing me weep, hover on top of the fridge, wings outstretched, tremble for a few moments then fly down to my knee to crouch, squeaking quietly, edging ever nearer until his body was close against mine, seemed to me at the time (as it does now, on reflection) an act of unexpected tenderness that I can interpret only as empathy. Chicken too will seek to be close to anyone in an apparent state of distress, jumping onto their knee, bending her head forward, attempting to be as close to them as possible. There may be other explanations of their behaviour, but I can't, at the moment, think what they might be. The fact that relationships between members of our own species are difficult enough to interpret and understand makes me wary of drawing conclusions from Chicken's behaviour towards Marley, whom she would often visit in whatever room his house had been placed. She'd stand near him for a long time, mostly in silence. I don't know if there was a bond of some nature between them, some avian connection, but I like to imagine that Chicken, in her way, tried to communicate with and reassure that nervous, anxious conure.