Corvus (16 page)

It's often suggested that, without language, thought (and indeed consciousness) is, if not impossible, then limited, but is all human thought
framed within language? Is there not impression, sense, a series of sensations, underlying the process of thought? Might it not be that there are other ways to think? Do we know enough of another species' language to know?

Certain ways of behaving are known to be the adjunct of intelligence in birds, playing and caching among them. Although some scientists are sceptical of the use of words such as ‘play' being applied to animals or birds since it's behaviour that would bestow no advantage in terms of survival or reproduction, many others recognise the extensive play behaviour of animals and birds, describing snowboarding ravens, crows who drop twigs then fly to catch them before they reach the ground, the teasing, chasing, amazing aerial displays. Why should it be different from the benefits of learning, social cohesion and enjoyment that humans derive from play? When I say that Spike enjoyed playing, I can think of few reasons that would have made him engage so vigorously in his magpie version of football, on his own or with anyone who was prepared to engage in this unusual sport, chasing a ball he had nudged with his beak, running after it when it was kicked for him by someone else, other than simply for pleasure. He loved play-fighting of all sorts, and his collection of toys, which he put carefully into and took out of his toybox.

Recently, coming out of work, David saw in the grounds of the hospital three rooks, this year's young, who had found a discarded but not empty lager can. They were pushing the can to and fro, jumping on it, rolling on the ground, trying to drink the remains of the lager. (It was after rain. There was plenty of water in puddles to satisfy thirst.)
It may of course have been, not play, but ‘brand recognition', like that of the crows described in
I
n the Company of Crows and Ravens
who have learned to recognise the logo of a well-known fast food company; perhaps the Scottish rook, so habituated to the sight of this particular lager, has decided that no other will do.

Chicken loves to play with paper, ripping it, tossing it into the air, scattering it. As I write, she's playing enthusiastically with an elastic band. For years, she played with the rubber mice I bought for her, throwing them around, pouncing on them, carrying them by the tail in her beak. Blue and red and yellow, they were routinely, inadvertently thrown out by me during house-cleaning. More were bought to replace them until the day when, very suddenly, for a reason I don't know, rubber mice disappeared. Someone somewhere had stopped manufacturing them. Everywhere I go now, every foreign city, I seek out pet shops, but without joy. The sole world source of rubber mice has gone. Instead, I've given her a rubber frog which she treats with much the same vigour as she did the mice although the frog is rigid, lacks the kind of tail by which it can be given a punishing shake. She doesn't think they're real, either frog or mouse. She doesn't like real mice. In autumn, when one or two intrepid field mice find their way into the house, I watch Chicken's reaction as they make their way across the study floor towards the scattering of food lying beside her house, the way she notices instantly that the mouse is there, the nonchalance with which she begins to look away, the casualness with which she jumps from the top of her house onto the floor cushion, the concentration with which she searches for something in one seam or
another before being overcome with a sense of urgency as she recalls that she has important though as yet undisclosed business in the kitchen. Later in the evening, I'll find her standing uncertainly on the strut of a dining chair, probably wondering if it's safe to go home. I'm glad she takes this view. I wouldn't like to have to deal with the consequences of territorial aggression. I clear up the food scraps and hope, as Chicken probably does, that the mice will go away.

It's the points of similarity between us that delight me still. I admire the birds' anger and their rage, for I too (perhaps about different things) feel anger and rage. I like seeing their apparently purposeless play, for it indicates to me that they have minds free enough from concern to do it. I am astonished, always, by the way they'll appear to know without knowing, to understand, anticipate, react, for it makes me feel as if I live in an indivisible world, that my belief that we're nearer in every respect than I could have imagined is correct, that we are, whatever we are, something of the same.

T
ime weathers us, wears away the differences between us. I think more now than I used to about Chicken, about all birds, about myself, about how we got here, how we came to be, and I realise that what makes us the same interests me as much as, more than, what makes us different. I’m fortunate in having this unique opportunity to observe, or to grow accustomed, for without it I’d know the differences, but not the similarities. I might have known about birds from reading, about their distribution and characteristics, the biological facts, the ways one calls them what they are according to the fluid requirements of Linnaean taxonomy: kingdom, phylum, class. I might have known the definitions that order us, place us, explain us, but I wouldn’t have known anything else.

Having observed, lived with a corvid for as long as I have has changed things, has reclassified us both, readjusted my observations,
my consideration of both our places in the world. I sit with Chicken on my knee in the quiet of evening, both of us in post-working-day philosophic mood, and it’s the moment when I follow our progress down through the stages of where we were and where we are, through the words that place us so precisely in evolutionary time. I begin with the fact that we’re both vertebrate, of the kingdom animalia both, both of the phylum chordata. I like this. It’s comforting. Hey Chicken, we’re in this together! Backbones! But then abruptly, alas, at class we part and at that point wander off separately into time and the development of our avian or mammalian ways, into our feather and our fur, into the byways of our biology and the benign or malign idiosyncrasies of what and who we are. But still we carry on down, further and further, into order, into family, into species, and on reaching this, the end point, or the sole end point of which we can have any certainty, looking across these last and final categories, genus, species, as
Corvus frugilegus
and
Homo sapiens
, again I am aware, as I always am, that there’s more for me to feel anxiety and guilt about than her.

I often wonder too about the point at which our evolutionary courses diverged, when she ascended on the path that would take her to an arboreal life of black feathers and wings and the enviable attribute of flight, while I proceeded stolidly through time to become what I am.
Don’t leave me behind
, I want to say to her,
I want to come
with you
, but there’s not much she can do about it, or I for that matter, it’s too late, a few million years, 280 million, give or take. Off she goes into the distinguished, elevated society of ravens, jackdaws, the witty
and eclectic circle of the crows of the world, while I – well, I find myself in mixed company.

At these moments ofontological reflection, it’s reasonable, even appropriate, for us to think of archaeopteryx, the first bird. I read, if not to Chicken then to myself, Edwin Morgan’s wonderful poem ‘The Archaeopteryx’s Song’ –

– and as I read I wonder, is Chicken, her grey rook’s face as familiar, as dear to me as would be that of any dog, any cat, representative of those who left behind the rock of scales, the weight of stone and armour? I look at her. Was she once a dinosaur? A small dinosaur, a maniraptor, but a dinosaur none the less? The answer to both questions seems to be yes. The qualification is there only because disagreement about the lineage of birds continues, a kind of three-sided contest with the fossil evidence at its core, to be disputed, taken apart; the argument of Linnaean classification versus cladistics or phylogenetic systematics,
the argument of what, in fact, a bird is and how long it has been one anyway; everything dependent on how the facts are assembled, on taxonomy or on belief, who belongs where, and for how long they’ve belonged there, arguments of definition versus diagnosis. (Definition tells you who is in a group. Diagnosis decides whether they should be there or not.) Once, if you had feathers you were a bird, but now, since the discovery of feathered, non-flying dinosaurs, even feathers don’t guarantee you any confidence in yourself and your place in the scheme of evolution.

The Linnaean system of classification, binomial nomenclature, building on Aristotle’s work two thousand years before, systematised the living world, made it possible to identify each organism, whether orchid or lemur, moss or crow, according to a hierarchy of kingdom, phylum, class. Wonderfully comprehensive as it is, it doesn’t take account of the evolutionary antecedents of any given organism. According to Linnaean taxonomy, all birds are of the class aves. Since nothing else is known to have feathers, feathers are a definition of ‘bird’ – if it has feathers, it’s a bird, and if it’s a bird, it has feathers. But, according to phylogenetic systematics, a clade – a single group of organisms – constitutes one ancestor and all its descendants, and since birds are (according to the view supported by cladistic analysis) descended from dromaeosaurid theropod dinosaurs, they are, in cladistic terms, dinosaurs.

There are other pressing questions, questions of relationships, questions of flight. Who flew and who didn’t? If they did, how did they? How flight evolved is still uncertain, since functional morphology – the study of the relationship between physical form and function – has
not yet resolved one of the major questions about flight, whether it had its origins in the movement upwards from the ground, with creatures (ungainly, clumsy creatures) running, then leaping, then taking to the air, the cursorial theory, or in their movement downwards, of leaping from tree to tree, a movement that became a pre-flight gliding, the arboreal theory. While the latter is the more likely – gliding down from a tree being rather easier than the alternative, which would have demanded considerable force to work against gravity – dispute remains. The ‘insect net’ theory, presented by the palaeontologist John Ostrom (an adherent of the cursorial theory), suggests that using forearms in a forward movement to trap and catch insects was the precursor to their development into wings as tools of flight. And all the time, the insistent voice to the side is shouting, ‘“
In the
beginning
…”!’

Tracking through the ages, through the unimaginable lengths of palaeontological time, ‘deep time’, negotiating those three mysterious letters that describe aeons, MYA – ‘millions of years ago’ – through Jurassic, Cretaceous, Paleocene, Eocene, Oligocene, Miocene, it’s possible to stalk the progression, trace the slow appearance of the relatives of the birds we know, and backwards too, from the birds around us to the first fossil specimen ever found that might have been a bird, archaeopteryx.

Archaeopteryx, tricksy, contentious, beautiful fossil of the beautiful name,
A
rchaeopteryx lithographica
, ‘ancient wings from the printing stone’. The first specimen of archaeopteryx was found in 1861, a spread of elegant bones, neck arched backwards by the tightening
bow of death, feathered wings preserved in finest detail by the carbonate limestone of Solnhofen in southern Germany. This
Urvogel
, protobird, emerged into the excoriating light of the modern age after 150 million years of darkness, of sharing the sediments of shallow, subtropical Jurassic lagoons with plant remains, with pterosaurs and insects, the forerunners of those who live today – ephemoptera, hemiptera, coleoptera – and with medusae, ammonites, crinoids and all the other palaeospecies held in states of near-perfect preservation by the anoxic conditions of the lagoon water, protected by the limestone deposits that would one day, because of their porous smoothness, be the medium of a different creation, becoming the lithographic blocks used by Degas, Munch, Escher, Toulouse Lautrec. A number of specimens have been discovered over the years but the best-known is the Berlin specimen, so called because it was bought by Humboldt University’s Natural History Museum, where it still resides safely in a heavy vault, providing as ready a source of dispute and minute examination as it did when it emerged into the light and heat of the arguments surrounding the nature of creation in the years after the first publication of Darwin’s
On the Origin of Species
in 1859.

Archaeopteryx’s fame comes from its significance in providing what, to some at least, is the incontrovertible link between dinosaur and bird. He remains until now the oldest specimen of feathered creature ever discovered, unique not only in his age but in the fact that he was the first fossil found to combine features of both reptile and bird. Archaeopteryx has a small skull with widely spaced, backwards-pointing teeth set into narrow jaws, clawed fingers, a long tail of twenty-two
unfused vertebrae, all of which are reptile features; but he has feathers too – asymmetrical flight feathers, leg and back feathers – and bones that are hollow like the bones of the birds around us today. He has anisodactylic feet (three front toes, one back, like modern passerines) with the hallux, the first toe, opposable; a furcula, or fused clavicles (what on our plate we’d call a wishbone); and a long, bony tail. He may have been ectothermic, cold-blooded, like reptiles, or homeothermic, warmblooded, like modern birds.

A CT scan of archaeopteryx’s skull and subsequent 3D reconstruction of his brain, carried out in a collaboration between the British Museum and the University of Texas, show that his brain was remarkably like that of a modern bird, although smaller, and that he had brain and inner-ear structures that would have allowed him to see and hear well, to balance and to fly. (I try to imagine what it must have been like to see the detail, the imprint of blood vessels, the space where the brain of a creature 150 million years old once was.) He probably had the experience of flight but it’s not certain what kind. While his brain would have allowed him to glide, the limited development of his shoulder bones might have prevented flapping flight.

The fossil record for birds is sparse by comparison with other creatures, the lumbering dinosaurs, the armoured, plated, plaqued boneheads Edwin Morgan writes of in his poem. Birds were, as they still are, light, insubstantial, hollow-boned things, lacking the weight that would have anchored them firmly, solidly in the mud to lie until chipped out, bit by bit, hacked or bulldozed, picked or brushed from the earth that was for millions of years their tomb and the source of
their preservation. Birds must have been, as they often are in death, blown away, trampled on, left to fold invisibly into earth, swallowed into the seething, busy depths of Jurassic seas. I think of them when I find small corpses occasionally in the garden, damp-feathered, camouflaged against soil, finches, a blackbird with its beak dulled into near-invisibility, the dead blue-tit lying on the stones of the path, colourless, now almost unidentifiable as what he was, even after a brief few days reverting back, melting into the substance of the earth.

(Fossil brains, like fossil birds, are rare, soft brain tissue decaying too easily for preservation except in very specialised environments. CT imaging and 3D modelling are the newer methods of reconstructing ancient brains, but most of what’s known about brain evolution has been learned by the use of ‘endocasts’, model brains produced using the cranial cavity as a mould. It was Tilly Edinger, daughter of the neuro-anatomist Ludwig, who, inspired by her love of childhood visits to the Senckenberg Museum in Frankfurt, became interested in fossils, working at the museum until 1938 when she was obliged to leave Germany. Moving first to Britain, she then went to America where, during pioneering years of study and teaching at Harvard, she became a distinguished founder of the field of palaeoneurology, the study of fossil brains.)

Thinking of archaeopteryx, I imagine him to have been big, as big as his reputation perhaps, as weighty as his provenance, his importance, his life among dinosaurs, but he wasn’t: he was small, the size of a magpie, the size, I assume, of my own magpie, Spike. One reconstruction of him that I have seen makes him black and white, with a
slightly mad look in his eyes and, apart from the rather odd addition of teeth, he looks remarkably, unnervingly like Spike.

If the very existence of archaeopteryx suggests a transitional stage between dinosaur and bird, acceptance of this has been, in the years since its discovery, strongly resisted by all those who would rather believe that birds sprang, or rather flew, fully formed from the hand of the Almighty at some indeterminate moment on the fifth day of His famously busy week, and by those who continue to argue, among other things, that archaeopteryx, being definitely a bird and therefore not representative of any transitional stage, proves conclusively that birds did
not
evolve from dinosaurs.

The world of creationism is more complex than I could have imagined, with ‘old earth’ and ‘young earth’ creationists, ‘progressive’ creationists and ‘gap’ creationists, as well as the adherents of a wide spread of theories: theistic evolution, modern geocentrism, intelligent design. According to ‘young earth’ creationists at least, the earth is less than ten thousand years old, a difficult position indeed, since, even beyond the confines of disputed palaeontological proofs, there are clear written and other records on earth of human civilisations that have been in existence well before the given date (apart from everything else, apart from science, apart from the utterly obvious, reliably proven facts that demonstrate that the earth and all that it contains have been around for more than a few thousand years).