Life: A Natural History of the First Four Billion Years of Life on Earthby Richard Fortey
An adventure...The first popular but authoritative biological history of earth [through] four billion years, written by a professional...a paleontologist with an extensive range of humane learning, and a gift for arresting language.
- Knopf Publishing Group
- Publication date:
- Edition description:
- 1 AMER ED
- Product dimensions:
- 6.59(w) x 9.57(h) x 1.23(d)
Read an Excerpt
The Everlasting Sea
Salterella dodged between the icebergs. While the small boat bucked and tossed, I hung over its side, peering down into the clear Arctic waters. I had not known that there could be such density of life. This frigid sea was a speckled mass of organisms. Tiny copepod crustaceans, looking like so many animated peas, beat their way in their thousands through the surface waters, feeding on plankton that I knew must be there, but which could not be seen without a microscope. There were jellyfish of every size: white, gently pulsing discs as delicate as spun glass; small pink barrage balloons decked with beating cilia, which appeared to be solid--but became gelatinous and impalpable if grasped from the water; an occasional orange monster with tentacles that promised evil stings for fish or mammal. They drifted in their millions, swirling and beating against the dumb tides, concealing purpose in contractions as instinctive as breathing, like protoplasmic lungs dilating and constricting in primitive obedience to the prompting of the currents. Behind the nearest iceberg arctic terns beat and hung in the air, peering down as I was, but with so much more precision, then darting to retrieve some living morsel from the sea. The ice floes were stained pink with their droppings.
Salterella was tackling a stretch of sea, Hinlopenstretet, between the islands of Spitsbergen and Nordauslandet far beyond the Arctic Circle at 80 degrees north. Ice floes had melted in the summer thaw, sculpted by the vagaries of weather into plates or crags, or simulacra of giants. On the waterline they were notched deeply by the sea, lapped by insistent waves, and just occasionally one would teeter into instability, cracking and keeling over with a great resigned splash which sent waves to make our small boat buck and grind against the smaller fragments of ice. It was true: the greater part of an ice floe was always beneath the sea, and you approached too close at your peril. If you looked down, you could see the bluish mass curving down into the deeps, while jellyfish skimmed hidden protuberances with impunity. Little Salterella sought the spaces between the floes. Her wooden construction was designed to cope with ice. Winds herded floes into clots that could become almost impenetrable. Then, suddenly, patches of clear water would allow rapid progress, and the bleat of the motor sent little auks and black guillemots fluttering low across the sea to plunder the rich waters elsewhere. In the distance a mysterious coastline lay low on the horizon. Glaciers ran straight down to the sea. Ice cliffs groaned or barked to signal the inexorable creep of sheets of ancient ice. The boat seemed like an interloper.
I was twenty-one and on my first expedition. Cambridge University had a tradition of sending young geologists to Spitsbergen. For a young naturalist it was very heaven. Here there were birds on every side that had only existed as pictures in bird books. The sea, the profligate sea, was a shimmering textbook of zoology. There seemed nothing to interfere with the joy of observation, no end to knowledge, no possibility that any discovery should be less than astounding.
The boat comprised two crew and several scientists, including myself and Geoff. We had already suffered in the old whaling vessel which had carried us from Norway, a switchback ride across the Barents Sea all the way to Spitsbergen. Few on board could face the whale-meat stew. Our expedition leader was the worst sailor of all, having disappeared below decks just after leaving the Norwegian port of Boda, and only reappearing a week later when we reached the base at Longyearbyen.
Geoff and I were to live together for weeks in a small tent, watching our beards grow from speckled patches to whiskers worthy of a Victorian paterfamilias. Together, we were in search of ancient fossils. An expedition from the previous year had stopped off to replenish their water supplies from a melt stream running off the great glacier of Valhallfonna in this remote and unwelcoming northern part of the archipelago. To everyone's surprise, the crew had picked up lumps of dark limestone on the beach that teemed with fossils: trilobites and brachiopods and many unrecognizable things besides. Nobody knew that fossil remains of such animals existed in this part of Spitsbergen. It was all completely new. But there had been no time to investigate that year because the Arctic night was closing in. Perpetual dusk was soon replaced by perpetual night. The few lumps of rock were brought back to Cambridge, and were studied by the great Professor Whittington, who pronounced them very interesting. Thus it was that two students came to be sitting side by side on Salterella looking at swarming jellyfish, and in such serendipitous ways lives are decided. It was 1967. "All You Need Is Love" was top of the hit parade, and stayed there for the whole expedition.
Expeditions are curious things. They last for weeks or sometimes months, during which time they acquire a life of their own, a structure, like a drama. Members of the expedition get to play roles, and the most curious aspect of all is that it is impossible to predict in advance quite what those roles will be. People have to get on together; there is simply no choice. Even pathological personalities have to survive the whole affair. There is, of course, the leader--well, there has to be--who has managed many of these things before. Of an evening, he recounts tales of blizzards past that make the present one seem tame. He knows stories of Nordenskjold and the other great men, who did it all with pemmican and huskies. He legitimizes the whole experience by accommodating the current namby-pamby lot within a great tradition. If you follow in the footsteps of giants, don't you walk taller yourself?
Then there is the expedition joker. He is not necessarily the wittiest man in the party, but he has a knack of igniting humour. Every member of the expedition likes to have him around in the evening. He has a generous gift of appreciating the humour of others, puffing up a glancing remark into hilarity, keeping flagging conversations alive, massaging morale. It is impossible to recall the humour that keeps an expedition afloat. It is concocted by the joker out of nothing and vanishes once more into nothing, but while it is there it seems to be the best thing in the world. The expedition's Practical Man knows how to fix a paraffin stove, or an engine. He can splice a broken guy rope. He can take out splinters, make splints; he can build machines from bits of wire and bottle tops. He is a wonder, as his ham-fisted friends who rely on him never tire of reiterating. I dare say that in ordinary life in suburbia Practical Man may seem a bit of a dullard, but when the outboard engine is failing among the ice floes he has his moment of glory. My own role, a modest one, was that of chef. Our food was nearly all dried: peas, onions, potatoes, rice, oats. Worst of all was the meat bar, 200 grams of dried protein which had to be reconstituted with hot water and which stayed insipid no matter what ingredients you added. Hours of ingenuity went into spinning these ingredients into something spectacular. I tried meat balls, curry, shepherd's pie, patties, pasties and pastries. I bashed them flat, or stuffed them with onion and peas. I married meat bars with oats. I was left undisturbed to follow my arcane trade, which was good news for one incapable of peering at an engine without exhibiting patent confusion. While Practical Man did his vital stuff, the leader led, and the joker cheered up the bystanders, the cook could be quietly abandoned to try to fabricate an onion souffle with powdered milk, flour, yeast extract and dried shallots.
The oddest role in the expedition is that of the scapegoat. His function is to take the blame for everything that goes wrong. A lost wrench? The scapegoat had it last. A leaking tent? You know who damaged the lining. Unexpected bad weather? Whose turn was it to check the weather forecast? Poor scapegoat. Unlike Practical Man, who can usually be identified in advance, there is no telling who will finish up as scapegoat. However, scapegoats have one thing in common: they never realize they are the scapegoat. They tend to be bumptious and self-confident types, convinced equally of their rectitude and their popularity. The scapegoat's function is, however, vital. He personifies mischance. Rather than curse fate, or wonder whether some god is playing tricks on a despised humanity, the scapegoat domesticates and humanizes misfortune. With the scapegoat there, nothing really bad can happen. And if the choice of scapegoat is as it should be, even he is unaware of the role he is playing. Peter enjoyed his expedition to Spitsbergen enormously, unaware that he was being blamed for everything from metal fatigue to blizzards. In this way an expedition defines its members. The identification of parts ensures the success of the whole, a formal intimacy is established, and the job gets done.
Geoff and I were eventually dropped off on to the shore of Hinlopenstretet, just the two of us, leaving behind our expedition roles, to find the fossils that had excited the previous year's collectors. It did not take long. In a couple of minutes there was a trilobite showing up all black on a white limestone slab. A few moments later there was another, and then another. The place was prolific! We danced around picking up any piece of rock that attracted our attention. Every rock fragment seemed to have something. This was the delight that animated Howard Carter at the tomb of King Tutankhamun. Nobody had ever seen these creatures before. Our eyes were the first to peer at the primeval rocks, to understand something of the ancient cargo they bore, to wonder at the preservation of extinct creatures on a bleak Arctic shore. In that harsh place there must have been something oddly incongruous about these capering enthusiasts.
But the tent had to be pitched. The shoreline was a beach stranded by the last great Ice Age, covered in shingle. The wind never ceased. Our tough tent was called a Whymper after Colonel Whymper, one of the great expeditionists. We tied the guy ropes on to spars that lay on the beach--logs brought in by the North Atlantic Drift to this island far beyond the habitat of any trees except the tiny arctic birch. Then we buried the spars in the shingle. Any gale would have to rip the tree-trunks out from their graves. Air beds and thick, real eiderdown sleeping bags provided such comfort as was to be had. That afternoon even meat bar bonne femme tasted wonderful.
There was no night--we were far too far north for that. But the leader had told us how important it was to keep to a regular pattern of sleep and work. If we failed to do so our minds would spin out of their proper biological rhythms; strange distortions of perception might develop. But sleep did not come easily when just a few yards away lay rocks that had never been explored before, our own personal slice of ancient history. Outside the tent, we could hear the ceaseless suck and rattle of the waves on the strand, the mewing of the gulls and the sharp cries of the terns. We had planted a flag on a pole, which chattered like distant gunfire in the incessant wind. Our minds could play, as we lay there, upon the fearsome polar bear, the isbjorn, who could flatten our tent with a single blow, and break a human leg with a single swipe. We even had rifles (of a sort) against his arrival. My feet were always cold when I climbed into the sleeping bag, and I wriggled deliciously in the warm cocoon until a gentle warmth crept slowly into my toes. Then I waited for the unconsciousness that would, finally, steal over me.
When our alarm clock woke us after the obligatory seven hours, we were into our woollen trousers and double anoraks in a rush, and out on to the rocks. Those pieces we had picked up on the beach must have come from rock outcrops beneath the gravel. Within a few minutes we had discovered where these outcrops were. All along the sea's edge there were low ledges of limestone, stacked one of top of the other, dipping down gently towards the water. The movements of the Earth that had long since elevated our ancient rocks had also tipped them gently. Limestone is a sedimentary rock, one that was built beneath ancient seas by the slow accumulation of sediment, making beds each a few inches to a foot or so thick. The top of each bed was a flatfish bedding plane, every one the surface of a former sea floor. So the beds of rocks we were admiring were like the successive pages of a book that recorded ancient time, logging time itself in limy mud that further time had hardened and transmuted into rock. On the bedding planes we could see shadows of trilobites, occasionally something clearer--a tail, perhaps. These fossils were the shells of animals that had once lived upon the sea floor, trapped, like Time itself, as part of the narrative in stone. As we looked along the shore we could see the rock beds dipping in ranks into the distance. Ice floes had come to rest against some of the thicker ribs of rock as they struck out into the sea like groynes, and mist concealed still more distant rocks in enticing obscurity. How much time might be buried here along this desolate shore?
And it was all ours! This stone diary had never been read before. There could be almost anything here, just waiting to be split from its rocky pages. We were standing near the top of the thickness of piled strata, so the beds that dipped towards us along the shore were progressively older the further away from us they were. We knew that as we tapped our way along the shore, so we also tapped our way back into geological time, exploring an older and older past, seeing what came before, and before that again. This simple method had built the whole elaborate edifice of geological time, the sum of a thousand narratives in stone-stacked order. Ancient seas had preserved their history in rocks. In time those rocks themselves would be preyed upon by newer seas, eroding history away again. But enough would survive to tell of life by then vanished, of the endless cycles of climate change, and of the hidden poetry of our mutable world.
Time, like an ever-rolling stream,
Bears all its sons away ...
In the weeks that followed we broke rock. Every fossil we recovered was logged into its precise place in the historical story. Notebooks were filled, sketches of rock sections were scribbled. Each specimen was wrapped in newspaper and tucked into a canvas collecting bag, and then the bags were collected into the same boxes from which we had taken our food. Out came porridge oats and dried meat, back went fossils. And months later I unwrapped with tremulous hands the little parcels which we had wrapped so laboriously when our fingers had still been stiff with cold.
The tools we used were geological hammers, tough enough to withstand endless battering without splintering, and hand lenses to peer closely at our finds. Some of our finds peered back, because certain trilobites had preserved the oldest eyes--convex, compound eyes, some as large as those of a dragonfly and with myriad polygonal lenses. We looked at one another for the first time, those trilobites and us, though hundreds of millions of years apart, and I understood that there could scarcely be a better metaphor for discovery. We soon found out that these trilobites had to be Ordovician (that is, about 480 million years old) because a few of them had relatives which we recognized from other sites, and some of the limestone beds also contained the fossils of graptolites, a well-known kind of extinct planktonic animal, which changed with every geological period in ways that students had to memorize. How glad we were then that we had drubbed into our brains the litany of species that spelled out geological time. But even with the little we knew we could see that there were types of fossil in these rocks that had never been seen before. We did not know what to call them, so we gave them nicknames--undergraduate-ish names like Mildred and Fred. Some years later they received the blessing of a scientific name, latinate and slightly pompous as they are supposed to be: Cloacaspis or Svalbardites. But the nicknames will be remembered, because they were generated in the hectic enthusiasm of those early days.
Sometimes the weather could no longer be ignored. Spitsbergen seems to be home to all the deepest meteorological depressions. One could imagine some Norse saga peopling its wet and inaccessible shores with carbuncular and bad-tempered trolls. Even in the middle of summer it was swept with squalls and driving drizzle. Specially small musk oxen live on the south of the island, sustained by meagre vegetation which would make the tundra seem lush. The struggle for existence was graven on the shores of Hinlopenstretet, too, where bones of stranded whales seemed to provide the only nourishment for an impoverished flora. Tiny arctic poppies huddled in hollows, and purple saxifrages seemed almost indecently colourful in a monochrome world. We were even too far north for mosquitoes (a blessing). The sheer joy of discovery usually kept the cold at bay: but even thick woollen gloves soon became tattered against the sharp rocks, and as our hair and beards grew we came to look more and more like dervishes belonging to some hermetic sect, especially if we jumped up and down to celebrate an unexpected find.
But a blizzard could not be faced out. We crawled into the tent and into our sleeping bags without even taking off our sweaters, and stayed there for several days. The howling wind mercilessly undid the good work of the summer thaw, plastering snow over rocks that had only just begun to yield up their secrets. This was when we discovered why the leader had recommended bringing War and Peace and The Brothers Karamazov. We got out of bed only to perform the most vital bodily functions, an unkind compromise between biological necessity and fear of frostbite of the private organs in which decorousness had little part to play.
Back in the feathered haven of my sleeping bag I could hear the sea lashing against the shingle. The waves that broke on the cold, grey arctic stones would have sounded the same in the Ordovician or the Jurassic. The sound was audible proof of the endurance of the sea.
The cauldron of life I had admired from Salterella was a different life--another set of animals, another ecology--from the life we had been hacking out of the rocks for the first time. There were no living trilobites, nor any Ordovician terns. Yet the sea endured. It was one constant in a fickle biosphere. The sea was cradle to the Ordovician animals which we were discovering: it succoured them while they were alive, and ultimately it provided for their entombment. I visualized the trilobite crawling over a soft mud nearly 500 million years earlier. Perhaps it died while it was moulting, overcome by noxious gases emanating from the sulphurous sediment. The hard carapace remained to record the life it had led, an archive of calcium carbonate, a shell for eternity. More fine mud covered the carapace, and as the millennia passed the beds above were slowly accreted. Occasionally, a tempest would dump more mud in a day than had accumulated for a century or more. Eventually, the pile of sediment hardened as its water was pressed out, and then followed the long annealing of geological time, millions of years, not mere thousands, before it became the dark rock I was now exploring. But still it carried its precious cargo. The chances of my making a connection with the fossil were still remote, because a hundred thousand incidents lay between the life of this humble invertebrate and my own--not least, if the hammer had fallen in a slightly different place the fossil might never have told its story. And consider what intervened between the Ordovician and the blizzard raging outside the tent: three ice ages, the deaths of a dozen continents and the birth of a dozen more, earthquakes and earth movements, mountain ranges thrown up and then eroded deep into their roots, the rise of fish and dinosaurs, the dramatic demise of the latter, bombardments of the Earth from space, and all the tangled skein of life winding around the changing terrestrial world like partners in a pas de deux. Chance and the consequences of chance ruled a blow of hammer on rock, arranging an assignation with history.
Fortuitous or not, this trilobite represented one moment in geological time, and within the section of rocks exposed along the Arctic shore a thousand preceding or subsequent moments were recorded. The story of geological time is pieced together from thousands of such fragments; some have been known for 200 years, others were recorded only yesterday. The rocks in Spitsbergen were my own little piece of the story--a doctorate's worth, if you like. The great narrative of geological time is a patchwork, a stitching-together of odd fragments with partial vistas, idiosyncratic, a tale put together by heroes and journeymen. And this narrative has a language of its own, the divisions of geological time that soon trip off the tongue with the ready familiarity of a railway timetable. Cambrian, Ordovician, Silurian, and so on, up the geological column, each of these again subdivided finely and more finely, the better to approximate history. It is an astonishing story, a tale of more than 3,500 million years. Consider what has happened since the death of Napoleon: the interpretations, the parade of historical facts, the controversies; and it will be obvious that a history more than ten million times as long can never be known, even in outline. And when this history has been stitched together from small pieces taken from rock sections where chance has had a part in the glance of every hammer blow, it will be certain that this history is a poor thing, an approximate story peddled by optimists.
The blizzard was over. We could return to our patient battering of the Ordovician rocks. A routine settled in, as regular as any office worker's. The alarm clock would wake us. A ritual curse about the weather and it was time to make the porridge--breakfast was always porridge. We used water from a melt stream, and would throw in raisins to make it more exciting. (A peculiar thing had happened to our taste buds. We loved the porridge to be very sweet--we poured granulated sugar over it until it was crusted. In civilized conditions it would have made us sick, but in this cold waste our bodies were hungry for calories in the most blatant form and the glutinous stuff tasted good.) We gobbled it down. Then to work. If we were working near by we could come back for lunch; if not, we put a few lifeboat biscuits into our pockets, and a bar of chocolate, and that would have to suffice for the day. Unless the weather was particularly miserable we would spend most of our time collecting the new fossil fauna, systematically, from each successive rock bed. Every so often something new or spectacular would turn up, prompting cries of delight, and then the lucky finder would hold it out for the other to admire. But the incessant wind was troubling. It never seemed to stop sweeping over the naked gravel of the vast, raised beach on which we lived. Although the temperature was above freezing the chill factor was dangerous; even with balaclavas and wind-proof jackets, woollen pullovers and woollen combinations that would have seemed old-fashioned to our grandparents the cold still managed to sneak in. At first we wore wellington boots: we often had to trudge for miles through slushy snow, and it was essential to keep the feet dry. But when we stopped walking a profound iciness would creep into the toes, and once it had taken control it was implacable until we climbed into our sleeping bags at the end of the day. It was a big moment when we discovered the mukluks in our supply boxes. These were a kind of giant canvas boot lined with felt--an Eskimo invention. They trapped the heat wonderfully well. Then it was only the fingers that ached with the chill. We were supplied with tins of Three Castles cigarettes made by W. D. & H. 0. Wills of Bristol, and I would light up, trembling behind whatever bluff I could find, as much for the brief moment of heat as for the nicotine.
From time to time there would be visitors. On the calmest day of all a walrus paid us a visit, cruising up and down the strait, and diving to grub up his favourite clam, the arctic Mya, a good-sized morsel the size of a large mussel. Every time he surfaced he would display his great tusks and blow out a massive, splashy breath, like some old colonel puffing outrage at intrusive strangers. Tiny, albino arctic foxes would appear as if from nowhere. They would eat anything, even our discarded porridge. We were so remote (or they were so hungry) that they seemed to be almost tame, even though their fur was hunted. I suppose their usual diet was the eggs and chicks of birds. They disappeared as quickly as they had come.
There was never a time without birds. They skimmed incessantly along the shore, battling purposefully against the wind: fulmars, effortless and aerodynamically perfect, flirting with the sea surface; terns, more laboured, beating hard sometimes to make progress. Least welcome were the skuas, those unappealing parasites. They lurked on the strand, and then relentlessly pursued some unfortunate gull, harrying and diving at the creature until it regurgitated its meal. The gull's final indignity was to have the contents of its evacuated crop swallowed in mid-air by its tormentor. The rich production of the Arctic sea supported all these animals. They were one with the pulsating jellyfish.
Geoff and I established a kind of working cordiality. With the arbitrariness which is part of an expedition, we had been chosen for our enthusiasm for palaeontology rather than any predictable compatibility. The truth was that we were as different as could be in every regard except for our love of fossils. After the expedition I do not think we ever spoke again. But while we were together we were obliged to share every belch and indiscretion. We evolved strategies. We talked about what we had found, naturally, and what we should collect that day. We talked about what we could do with the meat bars that evening, wondering whether we could perhaps make kebabs if we could only improvise glue out of flour. We speculated about the other members of the expedition. We made comments about the comparative odorousness of our socks. It was an odd, jokey relationship that was proximal without being intimate. I imagine it had the kind of closeness of a moderately successful arranged marriage.
We had chatted only briefly on the long cruise up the Norwegian coast. From the north of Norway we had crossed the Maelstrom together, past the Lofoten Islands to Bear Island, the most forsaken lump of rock in the world. Wild-eyed radio station operators had loomed out of the mist there to take off their supplies, comprising tinned food and whisky in approximately equal parts. A special breed of escapist seeks these places out--men (they are always men) who can only function at the edges of things, in a kind of solitary confinement, men who find the company of others difficult, and move and move again, motivated by a kind of inverse gregariousness, to where they can be almost alone. I was to meet their kind again in the Australian outback. This longing for solitude is apparently a progressive condition. After a while it is no longer enough to man the radio station with others: the committed loner seeks the chance to overwinter in some outstation, absolutely isolated. I met one man who had done just this: he had been confined by cold and darkness at the edge of the world for months. He told me wryly, almost sadly, that he had returned to Norway but found the crowds in Hammerfest, Norway's most northerly town, almost unbearable, and returned to Spitsbergen by the next available boat. Even as he talked to me I could see that his eyes were disengaged, looking out over the pack ice to where seclusion lay.
So Geoff and I developed a relationship which was an expedition relationship. But Geoff was a year my senior--he had completed his finals shortly before we left for the Arctic. Because of this year's difference I was Geoff's assistant, the hired hand--and at first he made the field strategy. But things were to change, because of another stroke of chance that would transform both our lives.
We were finding more and more new species, not just one but dozens. These trilobites were without names, a whole fauna through an uncharted stretch of geological time that had never been known before. As our collections grew, so did the realization that there was a lot of work here, just to make these new animals known. And how did they fit into the Ordovician world? How did they live? Just as, a metre or so away, the sea was profligate with variety, so, it seemed, was the Ordovician one--laid out upon plate after plate of rock before our inquisitive eyes. There were more fossil animals yet: snails and nautili and sponges and curious squiggles that defied our knowledge. Clearly, life in the sea had been a cornucopia of variety hundreds of millions of years before our hammers broke open its hidden plenty.
The excitement of discovery cannot be bought, or faked, or learned from books (although learning always helps). It is an emotion which must have developed from mankind's earliest days as a conscious animal, similar to the feeling when prey had successfully been stalked, or a secret honeycomb located high in a tree. It is one of the most uncomplicated and simple joys, although it soon becomes mired in all that other human business of possessiveness and greed. But the discovery of some beautiful new species laid out on its stony bed provokes a whoop of enthusiasm that can banish frozen fingers from consideration, and make a long day too short. It is not just the feeling that accompanies curiosity satisfied--it is too sharp for that; it arises not from that rational part of the mind that likes to solve crosswords, but from the deep unconscious. It hardly fades with the years. It must lie hidden and unacknowledged beneath the dispassionate prose of a thousand scientific papers, which are, by convention, filleted of emotion. It is the reason why scientists and archaeologists persist in searches which may even be doomed and unacknowledged by their fellows.
The urge to collect is different. It is clearly a deep urge also, because collected objects have been a part of human culture almost from its beginnings. There is even a Grotte du Trilobite, near Les Eyzies in France, a cave in which one of the earliest Europeans secreted a trilobite as a revered relic. Collecting is more than hoarding. Children will collect seashells from the beach, and rigorously sort them into types, by colour and design. They feel it is important, somehow, to get it right and, having done so, to keep the result. This kind of personal museum is part of the way we define ourselves, an archive of self, and is not mere covetousness or "stamp collecting." Children need to classify things in order to get a grasp upon the world. Discrimination and identification have value beyond the obvious separation of edible from poisonous, valuable from worthless, or safe from dangerous. This is a means to gain an appreciation of the richness of the environment and our human place within it. The variety of the world is the product of hundreds of millions of years of evolution, of catastrophes survived, and of ecological expansion. To begin to grasp any of this complexity the first task is to identify and recognize its component parts: for biologists, this means the species of animals and plants, both living and extinct. And to begin to negotiate this astonishing diversity a reference is needed, a sample of one species to compare with the next: in short, a collection. We start to understand our history by seeking to collect and classify.
There will be no end to what can be discovered from the rocks. Every year important new finds are made, and there is no sign that discoveries are becoming rarer. This is scarcely to be wondered at. Consider the millions of species that inhabit the world today. Many of these have still to be named and described. There are even occasional discoveries of new large animals--a previously unknown antelope was discovered in Vietnam only a year before this was written. And there is no end to beetles: we know only a fraction of the living species. A friend of mine, a beetle specialist, has "gassed" the canopies of tropical trees, and catches the animals that fall out in inverted umbrellas. It turns out that very few of the species obtained in this way have ever been seen before. Even with a modest extrapolation it seems that there may be millions of animals yet to be named in the living fauna. For humble animals like nematode worms there are untold hordes of unrecognized species--and these are much harder to define than beetles. Now they are being numbered rather than named, given molecular signatures which can be recognized again even without a name. But all these animals have a history, the millions known and unknown. This history fingers back through hundreds of millions of years, not an evolutionary tree so much as an evolutionary forest, and every branch possibly, or possibly not, recorded in the rocks. It is all a matter of chance.
The dice are loaded in favour of the preservation of some kinds of animals and plants. The most obvious bias favours organisms with hard tissues, such as shell or wood or bone, the common stuff of fossilization. So we would expect molluscs and fish to have a good fossil record, and we might doubt whether jellyfish or earthworms would have much record at all (surprisingly, they do have meagre ones). Because fossils must be preserved in sediments, it seems equally obvious that it will be common to find marine animals fossilized, and perhaps those that lived in lakes and rivers, while it is improbable that the eyries of eagles, or the bones of mountain goats, or the many inhabitants of high plains, will leave anything behind to tell of the history of these habitats. It is possible that Jurassic mountain tops were populated with fabulous, crested dragons that we shall never know.
So little rock is exposed at the surface, where it will catch the eye of the seeker--much more lies buried, hidden beneath the landscape, beneath town centres, golf courses or supermarkets. Occasionally, a lucky blow of a pickaxe, the excavation of new foundations for a house, or the opening of a brick pit will bring something to light that would otherwise have remained concealed. Exposure always partly depends on the toughness of rocks. Hard limestones form crags and escarpments, or sandstones bluffs, where there may be exposure of fossil-bearing surfaces. Soft rocks like clays will be exposed at the coast, but seldom inland, where they tend to form boggy vales in moist climates, or salt pans in dry ones. Then there are other rocks which may once have held rich booty from the past but which have been caught in the great vice of earth movements, buried deep inside mountain chains, squeezed and baked and changed through heat and pressure, and thereby metamorphosed into sparkling schists or mottled marbles; but then their precious cargo from the past will be obliterated. So we see the past through a shattered glass, darkly, nor can we tell which shards will be recovered to give us fragmentary glimpses of what once flourished.
I must return to the subject of geological time. All narratives require a scale. In novels, the scale is usually comprehensible in terms of the span of a human life, a few score years, maybe a few generations. This scale is appropriate to us. Our natural longevity is an instinctive yardstick, the measure both of our mortality and the changes wrought by time. We can understand shifts in history within a few generations, empathize with our grandparents, even dimly appreciate the problems of the thirteenth century. This is all but a moment in geological time, an instant which may fall between one hammer blow and the next. The narrative of life requires a scale of thousands to millions of years, acting over a drama of more than 3,000 million years. Geologists are insouciant in the face of these figures. Creation "scientists" simply do not believe them. In truth, it is difficult to grasp such an immensity of time because it is so out of kilter with our own brief lifespan. The temptation is to resort to homely metaphors. Imagine that the history of the world is represented by a clockface, say, then the appearance of "blue green" bacteria in the record happened at about two o'clock, while invertebrates appeared at about ten o'clock, and mankind, like Cinderella suddenly recalling the end of the ball, at about one minute to midnight. I do not know whether such images are useful other than as encyclopaedia illustrations. The domestication of time serves to trivialize a magnitude which should be held in awe. In some ways I prefer something vaguer but truer--at least symbolically. The great raised beach on which Geoff and I laboured in Spitsbergen, with its endless shingle retreating into the mist--the pebble to hand might mark the appearance of Homo sapiens. The farthest I could throw it might just reach to the age of the dinosaurs, while beyond that lay further beaches which could be seen more or less clearly, themselves composed of banks of pebbles, and then, into the mist, dimly perceived, more distant beaches, impalpable, remote, the outer reaches of Precambrian time. And, alongside, the sea, the eternal sea, linking pebble with pebble, framing time itself. Then at least we could appreciate the immensity of time, its countless instants, the fossil record perhaps a litter of shells upon the shore, a scattering of jetsam.
There are two scales of time: a relative one and an absolute one. The relative timescale is like the one Geoff and I were piecing together; this rock bed is younger than the one that underlies it, and older beds again lie further down in the rock column. A jigsaw of time is spliced together piece by piece from many such rock sections. Time is stacked in order, period by period. The names we all know--Cretaceous, Jurassic, Cambrian--were labels applied to great segments of this relative timescale long before it was known how many years each one comprised, or how far before the present the Cretaceous lay. The relative scale is still indispensable, and has been growing in precision ever since the great nineteenth-century geologists discerned its important lineaments. Fossil zones serve to define its small slices, a calibration which depends on the fact that extinct species had definite durations, so that the fossil fauna of one time differed from that of another. Some animals--ammonites and trilobites, for example--seemed to change faster than others, and these came to assume particular prominence in discriminating the relative scale. And all this depended on our human capacity for recognition, for placing things in order. Sedimentary rocks are often correlated from one place to another by means of the fossil faunas they contain. Stratigraphy is the science of such correlation. In some cases, rock correlations are quite straightforward. There have been moments in Earth's history when some great event, such as the impact of a meteorite, or a transgression of the sea over land, has laid a clear imprint upon the rocks. Faunas and floras alike bow before such events, which punctuate the fossil record like chapter headings in a story.
But in the majority of cases correlation is a subtle business, cluttered with argument and dispute. Papers are written that bat opinions back and forth. Gradually, a consensus is approached. Martin Rudwick has described how disagreement and personal conflict drove the debate about the Devonian System in the nineteenth century, how correlations sparked furious correspondence and personal enmities, and all for the delineation of one part of the relative timescale. Much of this argument originates in the rather obvious fact that the world is divided into different habitats, each with its own flora and fauna. Now we have no difficulty in recognizing that our arctic faunas are contemporary with tropical ones, freshwater with marine, deep water with shallow, even though they may share few common species. But far in the past these differences conceal contemporaneousness: how are we to distinguish difference in time from difference in space? How do we correlate between rocks of one part of the world and another? We do so by means of stepping stones that bridge separate places. For example, in order to correlate between the rocks laid down in ancient rivers and those laid down at the same time in former seas we are obliged to look for those rocks which accumulated in the contemporary estuaries, where the two environments met and overlapped, and where the calibrating animals of one realm might merge with those from another. The outcome is rather like synchronizing watches between different time zones. Once the connection is made we have only to know the time in one part of the world to be able to deduce what it is in another. In some future geological age the delicate bones of the arctic tern might link together arctic and temperate rocks--even tropical ones--for this far-travelled bird is a messenger for our times, a global ambassador of the Holocene. In this way, little by little, the relative timescale is refined.
The low chance of preservation of many animals and plants; the sheer numbers of species--every one coming with a history of its own; the chequered pattern of ancient environments; and the sundry difficulties in the way of correlating rocks between one part of the world and another, all combine to explain why we are unlikely to reach the stage when rocks will no longer yield news, and where what we know will be close to all there is to know. The history of life is filtered by the very processes that preserve it. "I am soft sift/In an hourglass," as Gerard Manley Hopkins said.
The absolute timescale produces a calibration of the age of rocks utilizing the radioactive decay of unstable isotopes (atomic varieties) of elements, or some other measure that ticks off years or moments. As decay proceeds, subatomic particles are emitted, and these can be registered by the crackling of a Geiger counter. This process provides a true clock, yet like all clocks it carries some error. Radioactive elements decay from an unstable state to a stable one; when half the original material has decayed its "half life" has expired. Half lives vary from a few moments to many millions of years, depending on the elements involved. Thus radiocarbon dating works best for archaeological material, because this form of the familiar element has a short half life. On the other hand, uranium isotopes provide very slow clocks, leisurely enough to pluck out time from the early phases of the solar system itself. All that is needed is a measure of how much of the original material has decayed, and by a simple calculation based on the rate of decay the time taken to effect the change can be deduced. There is a whole range of different radioactive elements which can provide clocks, like potassium-argon (K-Ar), or rubidium-strontium (Rb-Sr). It is almost a case of designer elements: choose the time period you wish to measure and select your appropriate radioactive decay series. Mass spectrometers, which can sift out atoms of one isotope from those of another, have vastly increased the accuracy to which small quantifies of isotopic material can be measured. This is how we know that the Earth is 4,600 million years old, or that mankind moved into the North American continent across the Bering Straits no more than 15,000 years ago. So absolute numbers of years are spliced on to the older, relative timescale, and even the most ancient history has become a matter of dates. The precision of these dates is continually revised as more and more accurate methods are developed for measuring smaller and smaller amounts of material.
But oddly enough, we seem to find it easier to handle the vastness of geological time by the system of dividing it into named chunks. We are more comfortable thinking in terms of the "Jurassic" than having to remember figures like "155 million years b.p." (before present); we prefer talking about the "end Cretaceous extinction" than recounting the events of "65 million years ago." In a similar way it is easier to understand recorded history if we can attach the label of a king or queen to a time period. Everybody seems to know what the Victorian era means, but how many can give the dates of Queen Victoria's reign? Of course, the real date is important, but the name allows us to grasp the inconceivable stretches of geological time, to turn an endless series of dates into something comparable with a family history. How much easier to toss around the word "Cretaceous" than to grasp the passage of tens of millions of years! And while the names are stable, the dates themselves may change as finer resolution is attained. I have seen the base of the Cambrian move upwards from 600 million years ago to 545 million years ago during my lifetime, and I dare say it will be refined further in the future--but it is still the base of the Cambrian for all that. What has happened is that dates--absolute dates--have been progressively corrected as more dateable rocks have been discovered, and erroneous dating has been eliminated. Measurement has become more accurate; new isotopes have been discovered and used to calibrate time. The hard and fast geological column given in textbooks is truly mutable--only as good as the last date, the latest technical refinement, or the experimenter doing the work.
More important than dates, or names, are the great events that happened. Just as we remember the Great Fire of London, or the Plague, or the age of the Pharaohs or Incas, so the events of prehistory typify their periods; the chronological names serve merely to pigeonhole them in the narrative. Phrases like "the Age of the Dinosaurs" acknowledge a prominent aspect of history without reference to millions of years; this is the stuff that is easily memorized. The Ordovician is distinguished from the Jurassic by a host of particular events, such as an Ice Age, and by having different fossil animals, which could be recognized even without the convenience of a chronology. The trouble is that events without a temporal framework become muddled; they conflate and blend. Who can forget the sight of dinosaurs threatening a voluptuous Raquel Welch in the movie One Million Years BC--even though cavemen and dinosaurs were separated by 65 million years?
Even in our relativistic age it is easier to understand a narrative with a beginning, a middle and an end. For the archives of life the beginnings are partly obscured and we do not yet know the end, but we are starting to understand something of the thousands of millions of years in between. The dates are hardening, while the relative calibration established in the last century still serves its purpose to make time familiar, and to give us a language of chronology.
When Geoff and I had spent a month on Hinlopenstretet we were visited again by Salterella. By now, we had filled four or five large boxes with our discoveries, and it was clear that we could fill as many more again before we left. The routine of our days had been interrupted by one four-day blizzard, and once by something much more terrifying.
I had been collecting on the shore when I looked up to see the shape of an isbjorn rushing towards me from the horizon at the distant headland. It was moving fast. It was clearly hungry, and, worse still, it seemed to be hungry for me. I did not trust my marksmanship--in fact, neither did I trust my rifle, which seemed to have been left over from some forgotten Afghan campaign. So I ran. Running in mukluks has all the delicacy of a show elephant performing a foxtrot. But I ran as one possessed, clearing shingle banks at a bound, scuttling over permafrost polygons, until my breath came in short, panicky gasps. I had to stop. My time to enter the food chain had come. Then I risked a glance over my shoulder. I saw that my isbjorn pursuer was a hallucination--no more than the top of an ice floe moving behind the headland. The floe had been propelled by a favourable wind, and its topmost crag presented a passable profile of a bear. For a few minutes it seemed as if the sharp keening of the terns was mocking laughter.
Salterella brought the post, the only delivery we had. There was something oddly unreal about reading domestic details from rural England, peaceful Wiltshire, while sitting outside your Whymper at 80 degrees north. The cat had died, poor thing. My sister had gone to university. There were sparrows in the thatch. The crew of Salterella told us of the progress of the other members of the expedition, the mappers to the south, the geophysicists inland. These were the real tough guys, pulling man sledges over the ice cap, husky and human combined. These were the only scientists who ate up their entire porridge ration; I guessed that they would have eaten the oat packets themselves to get more calories.
Then there was news of the Tripos. These are the end of year exams of the University of Cambridge for the Bachelor of Arts degree (and you get a BA, scientist or not). The name derives from a three-legged stool on which candidates once sat, and like so many things Cantab., the name was retained as a knowing anachronism. We had left for Spitsbergen soon after taking our exams, and because Geoff was a year ahead of me he had been examined for his final degree. We must have been bouncing across the Maelstrom when the results were posted outside Senate House. Now at last they had caught up with us. With some nervousness we opened the envelopes which had been forwarded from our colleges. Geoff, in his finals, had obtained a lower second class degree; but at the end of my second year I had got a first.
The significance of this took a little while to sink in, but when it did it devastated poor Geoff. He realized that to do an advanced degree like a PhD--even thirty years ago when things were less stringent--you needed to obtain at least an upper second, and preferably a first. It was immediately apparent that he was not, after all, likely to be a research student working on the wonderful new collections. On the other hand, his field assistant, the expedition cook ... well, if he had obtained a first at the end of his second year, it was more than likely he would do well in his finals. It would, after all, be I who would name all the new wonders from Hinlopenstretet.
Such moments decide lives. A different scrawl on a piece of paper, and both of us would probably have had different histories. Had our results been reversed it is unlikely that I would have been able to follow a life dedicated to pursuing the distant past, and Geoff might now be sitting in my chair at the Natural History Museum in London. Small turnings often lead to new routes, and only retrospect imposes a feeling of inevitability about these changes of direction. It is hard to unpick the effects of pure chance from matters more predictable and determined. Did I deserve my luck? As it was, Geoff went off to Belize after our return, to join the geological survey there, and I never saw him again.
Salterella left that evening. The Cap'n of the small vessel was cheerfully unaware of the serious consequences of his visit. He was more concerned with escaping from a clutch of ice floes that were to seal the two of us in for several weeks. Pack ice moves en masse, driven inexorably by the wind. Although there were exceptionally clear seas that year, this far north the major ice fields could be swept together by the perverse winds that scoured Hinlopenstretet, pushing together a dense pack too thick to be penetrated by a small boat like Salterella; and so it proved. It was colder, too. Gradually, as the end of the field season approaches in Spitsbergen, so the boreal light is slowly bled from the world. A creeping dimness pervades the day, so that close scrutiny of dark rocks becomes difficult, and you find yourself turning the specimen around towards a brighter quarter that is no longer there. As you prepare to leave the island for familiar and comfortable temperate latitudes a ghastly pallor informs the landscape, the distant ice caps merge with the fading sky, and if a weak sun appears at all it hugs the horizon like an undecided sunset. The shadows it casts are so long that you can project an attenuated self across 100 metres; a spindly stick insect in vaguely anthropoid disguise.
As we sat in our tent that evening Geoff consumed his whole whisky ration, neat, and with some deliberation. He had to get his resentment of our reversed roles out of his system. He became very drunk, and called me all kinds of names. There was certainly no other person or object at which he could direct his anger. Eventually I left the tent, and Geoff followed. Grabbing a piece of driftwood, he pursued me up the long beach, staggering from side to side and muttering, waving the wood in an approximate way, as if he were chasing a hornet. He was far too drunk to pose much of a threat. It was droll: two small figures marooned within a waste of ice on one side and an endless strand of shingle on the other, capering up the beach through a thin drizzle, the one in front loping away while a tottering figure behind flailed about with a sea-worn plank. After a while the expletives petered out. And eventually there was no place to go except back to the tent, and sleep.
In the morning Geoff was rather sheepish. But it was true: our roles had changed. From now on I was collecting for myself, devising the methods, setting the pace. I wanted to leave nothing behind. It says much for Geoff that after a short while he accepted the new conventions. The job had to be done; it was part of the ethos of the expedition. And, after all, in that remote waste, work was all there was. As if to reward us, on one perfect day the gloom cleared, the implacable wind dropped, and the sun bathed us in good light for twenty-four hours. It was so hot that we had to take off our shirts. Even the cries of the arctic skua took on a benign tone that day, lemonade crystals made a delicious refreshment, and meat bars tasted of protein. Days like that hardly ever happen on Spitsbergen. The joy of such moments healed any differences between us. Like W. B. Yeats,
My body of a sudden blazed;
And twenty minutes more or less
It seemed, so great my happiness,
That I was blessed and could bless.
For the final week or two we desperately tried to sample the earliest parts of the rock section. By now, all our gloves were in tatters, shredded by hacking at the obstinate limestone. The incessant wind had whipped our hair into gorgon-like curls, matted beyond the reach of any comb. Our beards were thick and curly, a kind of natural pelt. Our woollen combinations, lived in day and night, had become an indefinable shade of grey. When we left, they were thrown over the side of the boat with some ceremony. The garments sank steadily, and I sometimes wonder what generations of jellyfish they nourished. Before we left, we had one last visit--from the Susselman. The Susselman is the Norwegian governor of Spitsbergen, and he travels the island during the summer in an official yacht or schooner, a magnificent sailing boat with brass trimmings maintained in the kind of style that always (perhaps only) seems to accompany a diplomatic function. The arrival of a fairy godmother on Hinlopenstretet could not have been more surprising. We were invited on board for canapes and sweetmeats. There could have been nothing more incongruous than two hirsute and malodorous young men being served canapes by a uniformed servant at 80 degrees north. The Susselman must have regarded his previous visit to the Russian governor of Barentsburg as a comparatively cultural occasion, even though it was well known that a Soviet posting to Barentsburg was a punishment for drunkenness at best, venality at worst, and usually some interesting combination of the two. He must have been glad when we boarded our dory and left for the bleak shore once again.
In truth, we, too, were glad when at last we were picked up by Salterella for the journey back to Ny Alesund towards the south of the island, happy to get out from under canvas, and with our precious cargo of fossils stored in the hold. Like love affairs, expeditions usually continue just a little too long. The end is always a little rueful, and tinged with impatience.
On our way home we stopped at Biskaerhuken at the northern tip of Spitsbergen, where it was still possible to pick up items of Nazi cutlery from the beach (the place had a strategic importance in the Second World War). A few metres away from the hut at Biskaerhuken there were graves of whalers, who had hunted these seas more than a century before the Allies had fought Hitler here. Simple wooden boxes were covered with gravel, and the corners of the makeshift coffins could be seen emerging here and there from their rubbly cover. We were evidently just the last in a long tradition of visitors to the Arctic. In our own way, we had plundered, too, but our visit was for the enrichment of knowledge rather than monetary gain. It was difficult to imagine how we could have explained our motivation to a nineteenth-century whaler, or even to a Nazi U-boat commander. We had discovered the evidence for a small piece of the narrative of the history of life, a unique piece, and our own. It was to be one small contribution to the greater history that can never be fully discovered. We had rifled a small file from rocks that had been set for eternity.
This account of the expedition to Spitsbergen in the late 1960s serves as a metaphor for the themes that pervade this book. The expedition had its reverses and surprises; chance had a part to play, both in discovery and in our own story; and on one occasion my personal fate was changed by the merest detail on a piece of paper. The important steps in discovery and history are often down to such details, the pivotal event rubbing shoulders with the mundane. Discovery is intimately intertwined with the discoverer. There are plenty of accounts in encyclopaedias and textbooks that treat the narrative of life as if it were a scenario for a documentary movie. Event seems to tread inexorably upon event, fact upon fact, in a chronology recited by rote. The real business somehow seems to be absent. Neither the awe the story should command is there, nor its curiously human dimension, as when one discoverer wrestles with his rival to uncover history, or a stop for fresh water on Hinlopenstretet reveals hidden treasure. My own account, which I call an unauthorized history, will pick a more idiosyncratic way through thousands of millions of years of life. No event of real moment will be omitted, but it is impossible to be compendious: there is simply too much history, and the story will be shaped as much by what has been left out as by what has been included. Isaac Newton famously described his sampling of phenomena from the physical universe as a kind of beachcombing, whereby he could pick up only the brightest shells that caught his eye from an infinite litter on the strand. Like pebbles on the beach of Hinlopenstretet, history, too, is a succession of endless details, and there is an infinite choice whether to pick this one or that. And where my own experiences with people or places will serve to bring the process of investigation alive then I shall make diversions, the better to illuminate the way forward. Scientists are supposed to eliminate their personal voice, which no doubt works admirably for technical journals, but such spurious objectivity jettisons an awareness of much of what makes the process of discovery exciting, interesting, and informed with the whole inventory of our frailties and virtues.
I must mention the bugbear of teleology--ascribing purpose to all evolutionary activity, as if the whole of creation were striving for perfectibility. It is tempting. The nature of adaptation is improvement of design--or at least of fitness. It is attractive to think of animals or plants willing themselves to get better and better, more adapted, as if life were some kind of capitalist enterprise with an eye to ever-increasing sales and productivity. A contrary view attributes almost everything in evolution to the operation of heartless chance, through which lif e blunders like a blind man in a battlefield. Luck controls survival rather than genetic virtue or perfection of adaptation. Battered by fortune, controlled by the toss of countless dice, fortunate species survive a filter of fate. There is no real conflict here. I see no point in becoming obsessed by narrative objectivity in a fruitless attempt to worm out the human from descriptions of history. Like it or not, human motivation will creep into descriptions of the natural history of animals and plants; it is impossible to consider the biological world without colouring it with our own humanity. We know that the human expression of emotion is mirrored in the snarls or grimaces of animals, and that the genetic bond that unites all mammals runs to more than the sequences of chemical bases in the DNA molecule. There is a commonality to life, and it is not a failing to acknowledge it. Equally, there are cases where chance is in control, as random as the impact of a meteorite, a sudden reverse, like the arrival of a letter bearing unexpected and momentous news.
All stories need a chronology. Geological time is paradoxical and difficult. The further back in time we go the more obscure are the events, the less certain the narrative. To approach the story of life in the most logical way, we might start at the present day and work backwards. We know a great deal about the last few thousand years, and thanks to radiocarbon dating and dendrochronology, we can date events precisely. By the time we get to the Pleistocene, about 1 million years ago, we would only be able to date many events to within a few thousand years. Further back again, to the time of the dinosaurs--say, 120 million years ago--and the accuracy would have shrunk to a few tens of thousands or perhaps hundreds of thousands of years; and back to the time of the trilobites--say, 400 million years ago--maybe half a million years might be the best margin to which we could correlate events. But life stretched back further, much further, until at 3,500 million years ago it has been debated whether the traces of life are life at all. At this distant time, the possibility for aligning an event in one part of the world with that in another might be askew by some millions of years. And the further back in time the less the fossil record has been preserved. As rocks have been recycled time after time--through erosion--less and less of the oldest crust of the Earth survives, and often this durable ancient crust has been baked or squeezed in the vast mill of mountain chains until little of its original character remains. The past is continually erased, and the record of the most distant time survives only by a chain of minor miracles. Some commonplace detail is most likely to endure; the few regular soldiers who walked unscathed from the Battle of the Somme in the First World War were probably more lucky than skilful. Like those distant bluffs that we observed when we first landed on the shore in Spitsbergen, the remotest past is dimly perceived and full of mystery, enticing but very obscure.
In spite of the attractions of working backwards through time--from the familiar to the arcane, from the clearly seen detail to the slimmest speculation--I prefer to begin near the beginning and proceed towards the present time. Stories often work best in chronological order, and this is particularly important in stories like mine with tangled plots, odd subplots, and characters who disappear, never to return. The history of life is more convoluted than any novel by Charles Dickens, and the satisfactory ending is far less guaranteed. So I must begin with what is most ancient but least known, and end with what is almost historical fact, a geological yesterday. The story will come progressively into focus as the present day is approached. Our own memories of our earliest years are also hazy and unfocused; maybe a great event will be recorded vividly but without detail. Events from our youth, and the formative experiences of adulthood, comprise a robust chronology, recalled with the same intensity that still suffuses the memories of my first expedition. Events of yesterday or the day before can be looked up in a diary. So the chronology of geological time parallels the pattern of memory, a faculty which is peculiarly developed in our own species. It is just that the timescale is expanded 45 million times from that of our own puny lifespan.
Even so, it is an incomplete story: for it comprises only the middle part. The early history of the Universe--especially its first few seconds--are the province of astronomers and theoretical physicists, and the language of their history is written in complex mathematical equations. At that genesis, the forces that shaped the story of our Earth, including gravitation, magnetism and electricity, were married in an extraordinary unity that, once shattered, will not, it is claimed, recombine until the end of time itself. The great outward explosion of time and matter at the "big bang" was a factory of creation, making heavier elements from lighter ones in a series of nuclear reactions the like of which have never occurred since. The Universe literally made itself, nearly 13 billion years ago. Matter exploded outwards in a diaspora which is still only dimly understood, forming strings of galaxies, each one of which ultimately came to be composed of millions of stars. And in the corner of one of these galaxies, the Milky Way, clouds of interstellar dust and gases were drawn together by gravity, and thus the sun was born. There are millions of similar stars, for there was nothing unique about the series of events that led to the Sun's birth, but as yet we know of no other star that gave life. When this matter congealed, conditions were right for the onset of the thermonuclear reactions that still fire the furnace at the heart of the Sun's warmth. This is the warmth that nourishes life. An intuitive appreciation of this fact inspires Sun worship by native peoples on almost every continent. They believe that the observation of ritual alone sustains the daily or seasonal reappearance of the Sun, without which life would cease. And they are right: if the warmth were switched off, even for a few seconds, it would be instant death for all living things.
This early history of the solar system predates life, although if it had happened one jot differently, there would have been no living cells. But this is not our story.
At the other end of time there is written history, and all the paraphernalia of human civilization. Here the province of the palaeontologist gives way to that of the archaeologist and historian. But there is an ill-defined area between. The domestication of animals was a momentous event in human evolution, and may have happened on the interface between prehistory and history. Recently, many of the crucial thresholds in the story of humankind are being recognized as having happened earlier than was once thought, just as the origins of our human species are more antique than was realized twenty years ago. If anything, the compass of palaeontology is growing. But like palaeontologists, archaeologists dig, albeit in soil that overlies rock formations, delving into the waste of vanished generations, the shards and ordure, the forgotten fragments of abandoned buildings. Other than ritual burials, the stuff of archaeology is mostly the bits that people no longer wanted and threw away, or buildings neglected until they fell down. Archaeologists, too, often have to make do with fragments of durable material as a means to reconstruct a fuller narrative, and they are also constrained by the principles of stratigraphy as they dig downwards, layer by layer, deeper into the past.
The narrative that concerns me lies in the vast tract of time after the Sun blazed into heat, fired by its hydrogen furnaces, and before humans started making pots, building ceremonial centres, and recording the details of their daily transactions on pottery slabs. This is quite enough to be getting on with.
Meet the Author
Richard Fortey lives in London.
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This has become one of my favorite books on the subject. Fortey tells an accessible story with wit and color. He effortlessly takes you back through history.
Fun and fascinating. I can reread this endlessly and always find something new to enthrall me. The only complaint? As a neophyte in this field I could have used a chart laying out the various ages and their span. Otherwise, a great read