Life: A Natural History of the First Four Billion Years of Life on Earth - Brossura

Fortey, Richard

Brossura

ISBN 10: 037570261X ISBN 13: 9780375702617

Casa editrice: Vintage Books, 1999

Riassunto

A New York Times Book Review Editors' Choice

"Extraordinary. . . . Anyone with the slightest interest in biology should read this book."--The New York Times Book Review

"A marvelous museum of the past four billion years on earth--capacious, jammed with treasures, full of learning and wide-eyed wonder."--The Boston Globe

From its origins on the still-forming planet to the recent emergence of Homo sapiens--one of the world's leading paleontologists offers an absorbing account of how and why life on earth developed as it did. Interlacing the tale of his own adventures in the field with vivid descriptions of creatures who emerged and disappeared in the long march of geologic time, Richard Fortey sheds light upon a fascinating array of evolutionary wonders, mysteries, and debates. Brimming with wit, literary style, and the joy of discovery, this is an indispensable book that will delight the general reader and the scientist alike.

"A drama bolder and more sweeping than Gone with the Wind . . . a pleasure to read."--Science

"A beautifully written and structured work . . . packed with lucid expositions of science."--Natural History

Su questo libro

L'autore:

Richard Fortey lives in London.

Estratto. © Riproduzione autorizzata. Diritti riservati.:

   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 strea,
                     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 w...

Su questa edizione

• Editore: Vintage Books
• Data di pubblicazione: 1999
• ISBN 10: 037570261X
• ISBN 13: 9780375702617
• Rilegatura: Copertina flessibile
• Numero di pagine: 346