Life

by Tim Flannery

  As I write, outside the plane a vermilion line announces the coming of the day. I’ve seen it often enough from below, but from up here it is a miracle. Galah-grey clouds stretch from horizon to horizon, sculpted by winds into a monochrome rippled beach, through which the rising sun spills a lava of pink—an eerie rose glow from below, piercing the cloud in strange patches.

  My jetlagged mind is suddenly thrown back twenty years, to the other side of that ripplefield of cloud. I’m in the loneliest desert on earth, wandering towards camp after a day spent searching for fossils on the shores of a dry salt lake. I move along the crest of a blood-red sand dune, its summit a maze of dead-looking clumps of cane grass and sandy blow-outs. It’s been a long, hot day, and my water ran out hours ago. There’s not a sound, not even the wind, to remind me that I share the Earth with another living creature.

  My eyes are trained to scan the ground for the tiniest fossil—I usually find the lost earring, the contact lens, the money on the pavement. Now I see a minature black dragon, its body thrown into an S-shape that is half buried in sand at my feet. My tongue rasps against the roof of my mouth as I muse on the tricks that an exhausted and dehydrated brain can play on you. Surely this is nothing but an oddly shaped stone—I see a miniature black dragon, its body thrown into an S-shape that is a mirage of a fossil of a mythical creature that’s been awaiting me in this lonely spot since the Dreamtime? I pick it up, but immediately drop it. I can’t interpret the sensation in my fingertips, then I realise I’ve been burned. I bend once more to pick up the mysterious object—more cautiously this time—juggling it to dissipate the heat. Incredibly, it is a miniature dragon—made of brass and blackened by time, which has lain there all day on the dune crest storing up the heat of the sun. It is one half of an old Chinese belt buckle that, intertwined with a brother, once upheld someone’s dignity. Is it possible, I wonder, that an errant Chinaman, bound for the goldfields of Ballarat, perished out here by Lake Eyre, leaving the buckle as the only testimony to his existence?

  Then I see the chips of stone and the bleached and broken bones of a desert rat-kangaroo—like the scattered skeleton of a young rabbit in the sand. This animal was last sighted before I was born—indicating that a Wangkangguru hunter once sat here, relishing a delicious meal of oolacunta, as the tribe knew the marsupial.

  Perhaps the lucky Wangkangguru had been given the belt, and maybe a pair of pants as well, in exchange for leading an explorer to water or in payment for mustering cattle for some forgotten pioneer. Or perhaps the solitary half-buckle had been traded in from the coast by Aborigines before the European pastoralists ever arrived, its lively depiction of the dragon and metallic lustre endowing it with a power that moved it along the great trade routes in exchange for pituri or stone axes, until at last it pierced to the heart of the continent.

  Whatever the case, the buckle had reached its resting place in the sand by the time of the Great Depression, for that is when the oolacunta was last seen alive. The diminutive creature had the finest lines of any member of the kangaroo family—all legs, grace and energy—with fore-limbs so tiny that they almost disappeared when, in full flight, it tucked them up close to the body. At under a kilogram and with fur the colour of fine beach sand, it was a mere atom of life in the vastness of the inland, an almost ethereal being whose appearance and disappearance is a profound biological mystery. First described in 1843 by the great English naturalist John Gould, who gave no indication that it was rare, the oolacunta promptly vanished into thin air and was not seen again for nearly ninety years.

  Almost everything we know about the creature was learned through the agency of a single man—the one-eyed, one-handed Hedley Herbert Finlayson, a chemistry tutor from Adelaide University who braved the desert on camelback during the height of summer in 1931 to investigate sightings of a tiny rat-kangaroo in the far north-eastern corner of South Australia. Finlayson is a true unsung hero whose achievements as an amateur mammalogist, at a time when so many scientists were seeking advancement through study at Oxford and Cambridge, read like high adventure. His journeys, which twice nearly cost him his life, were made at a time when many Australian mammals were disappearing, and they give us a glimpse of many now vanished creatures. To find the desert rat-kangaroo Finlayson had to penetrate the endless plains and sand dunes of the Lake Eyre Basin. At times all he had to eat was curried oolacunta, for he had great success in his quest.

  He found the species living in the vicinity of Cooncherie waterhole, and was flabbergasted to observe that, in this hostile country where the temperature at ground level is often in excess of 50° Celsius, the oolacunta never sought shelter in a burrow, instead making do with a loose nest of sticks constructed on the open plain. Despite their size they were as brave and dogged as the largest red. Finlayson wrote:

  We had ridden less than half an hour when there came a shrill excited ‘Yuchai’ from the horse-boy furthest out, and the chase was on…Tommy came heading back down the line towards the sand-hill, but it was only after much straining of eyes that the oolacunta could be distinguished—a mere speck, thirty or forty yards ahead. At that distance it seemed scarcely to touch the ground; it almost floated ahead in an eerie, effortless way…as it came up to us I galloped alongside to keep it under observation as long as possible. Its speed, for such an atom, was wonderful, and its endurance amazing.

  We had considerable difficulty heading it with fresh horses. When we finally got it…it had run us twelve miles; all under such adverse conditions of heat and rough going as to make it almost incredible that so small a frame should be capable of such immense output of energy…

  In his private notebook Finlayson recorded, in a terse, yet admiring way how the chase ended. ‘Finally he staggered and dropped, and lay gasping…Difficult to imagine anything gamer—only stopped to die.’ For twelve miles this tiny creature, weighing just under a kilogram—less than a rabbit or cat—had outpaced one fresh horse after another! What I would give for just a single day with an oolacunta, to observe and learn how this most amazing of kangaroos lived, for it is the very epitome of the toughness needed to survive in Australia. As it was we learned shamefully little about it before it became extinct except that, unusually among kangaroos, the females were larger than the males, suggesting that females were dominant.

  In London I glimpsed what were probably elements of its success—a massive nasal cavity that gave the head a unique broadness, a black band of fur below its sandy outer layer, and bare patches on its arms, chest and inner thigh. Its huge nasal region may have cooled the scorching air before it reached its lungs, as well as extracting precious moisture from the exhaling breath. The black band in the fur may have retained warmth on a cold desert day—perhaps when the creature ruffled its coat slightly so as to expose it—and perhaps it licked its bare patches, which would have been shaded as it sat, the evaporation dissipating the unbearable heat of summer. Whatever its many secrets, they added up to a unique animal, one that could lie on the open plain in its flimsy nest all day, enduring the worst of desert conditions, but at the slightest danger rise and take off in a straight line—for twenty kilometres if need be—purchasing its survival with unique speed and endurance. Taken as a whole, the creature’s strategy makes sense; its flimsy nest was simply a resting place from which an approaching predator could easily be spied. For such a creature, seeking refuge in a cool burrow where it might have been trapped was a far poorer option.

  There is the faintest glimmer of hope, fanned in part by its previous near-century-long disappearance, that we may see the oolacunta once again. In the 1970s workers on the dingo fence in western Queensland reported a kangaroo the size of a football running along and bouncing off the netting, and from time to time similar sightings are reported in the Lake Eyre Basin. As with the thylacine, however, every year that goes by without rediscovery increases the likelihood that the species is truly extinct.

  There is a rather sad ending to the story of Finlayson and his oolacunta, for when he
published his bestselling book The Red Centre in 1935, he was taken to task by Ellis le Geyt Troughton, curator of mammals at the Australian Museum, for collecting such rare creatures. It was an attack motivated in part by envy, but Finlayson’s amateur status left him vulnerable to such pronouncements—indeed criticism by professionals seemed to dog him all his life. A particular bitterness came in the 1950s and 60s, when the Australian Mammal Society was founded as an association for ‘professional mammalogists’. Despite pleas from some members, Finlayson refused to join, for he had been sensitised to the stigma of ‘amateur’. For the rest of his life this fascinating man, who lived to be nearly 100, never married, drove a car, or owned a television or phone. He kept his priceless specimens in his house in North Adelaide and only after his death were all 3000 deposited in a collection in the Northern Territory.

  From the air the country traversed by Finlayson looks as if its deep geological history has been written in braille, with each dune and ripple telling of bygone winds and weather systems. The dunes run north–south below me, so Uluru must be off to the north-west. I know that because the winds that once marshalled those countless sand grains were generated by a vast high pressure system that sat almost directly over the great monolith. Then—15,000 years ago—Australia was a Sahara, so dry and windy that the heart of my country was little but shifting sand.

  Soon Algebuckna waterhole on the Neales River appears, its narrow waterway a glistening thread of silver in the morning sun, pointing straight at Lake Eyre. I imagine the pelicans slowly shuffling in the dawn light, the cormorants at their perches preening as the sun touches the crowns of the red gums. Then the vast, silvered extent of Lake Torrens, the Flinders Ranges forming its stately backdrop. After that, Spencer Gulf, and finally touchdown in Adelaide. I’m fresh from the wonders of Europe and America, but this is the most mysterious and beautiful country on Earth.

  The Great Aerial Ocean

  2005

  The great aerial ocean which surrounds us, has the wonderful property of allowing the heat-rays from the sun to pass through it without its being warmed by them; but when the earth is heated the air gets warmed by contact with it, and also to a considerable extent by the heat radiated from the warm earth because, although pure, dry air allows such dark heat-rays to pass freely, yet the aqueous vapour and carbonic acid [CO2] in the air intercept and absorb them.

  ALFRED RUSSEL WALLACE, MAN’S PLACE IN THE UNIVERSE, 1903

  IF WE ARE to understand climate change we need to come to grips with three important yet widely misunderstood terms. The terms are greenhouse gases, global warming and climate change. Greenhouse gases are a class of gases that can trap heat near Earth’s surface. As they increase in the atmosphere, the extra heat they trap leads to global warming. This warming in turn places pressure on Earth’s climate system, and can lead to climate change. Likewise it’s important to have weather and climate sorted out. Weather is what we experience each day. Climate is the sum of all weathers over a certain period, for a region or for the planet as a whole. And all, of course, are generated in the atmosphere.

  The atmosphere has four distinct layers, which are defined on the basis of their temperature and the direction of their temperature gradient. The lowest part of the atmosphere is known as the troposphere. Its name means the region where air turns over, and it is so called because of the vertical mixing of air that characterises it.

  The troposphere extends on average to twelve kilometres above the Earth’s surface, and it contains 80 per cent of all the atmosphere’s gases. Its bottom third (which contains half of all the gases in the atmosphere) is the only part of the entire atmosphere that is breathable. The key thing about the troposphere is that its temperature gradient is ‘upside down’—it is warmest at the bottom, and cools by 6.5°C per vertical kilometre travelled. At first sight this appears contrary to common sense, for you would expect the air nearest the sun (the ultimate source of heat) to be the warmest, but this peculiarity accounts for the well-mixed nature of the troposphere—after all, hot air rises. Another peculiarity is that the troposphere is the only portion of the atmosphere whose northern and southern halves (divided by the equator) hardly mix, a characteristic that spares the inhabitants of the Southern Hemisphere the polluted air that limits horizons and dulls panoramas in the more populated north.

  The next layer of the atmosphere, known as the stratosphere, meets the troposphere at the tropopause. In contrast to the troposphere, the stratosphere gets hotter as one rises through it. This is because the upper stratosphere is rich in ozone, and ozone captures the energy of ultraviolet light, re-radiating it as heat. Because it is not disturbed by rising hot air, the stratosphere is distinctly layered, and fierce winds circulate within it.

  Some fifty kilometres above the surface of Earth lies the mesosphere. At −90°C it’s the coldest portion of the entire atmosphere, and above it lies the atmosphere’s final layer, the thermosphere, which is a thin dribble of gas extending far into space. There temperatures can reach 1000°C, yet because the gas is so thinly dispersed it would not feel hot to the touch.

  The great aerial ocean is composed of nitrogen (78 per cent), oxygen (20.9 per cent) and argon (0.9 per cent). These three gases comprise almost all—over 99.95 per cent—of the air we breathe. And interestingly, its capacity to hold H2O depends on its temperature: at 25°C water vapour makes up 3 per cent of what we inhale. But as with the watery oceans it’s the minor elements—the remaining one-twentieth of one per cent—that spice the mix, and some of them are vital to life on this planet. Take, for example, ozone. Its molecules, composed of three oxygen atoms, are scarce even within that tiny minority of spicing gases, which scientists refer to as ‘trace’ gases. Ozone makes up just ten molecules of every million tossed about in the currents of the great aerial ocean. Yet without the shielding effect of those ten in a million, we would soon go blind, die of cancer or succumb to any number of other problems.

  Just as important to our continued existence are the greenhouse gases, of which CO2 is the most abundant. With fewer than four of every 10,000 atmospheric molecules being CO2, it can hardly be called common, yet it plays a vital role in keeping us from freezing, and (by its rarity) from becoming overheated. Partly because of it, the average temperature of the surface of our planet is now around 14°C, and ever since complex life first evolved, CO2 has helped keep it above freezing.

  We are so small, and the great aerial ocean so vast, that it seems hardly credible that we could do anything to affect its equilibrium. Indeed, for most of the past century humans have held to the belief that climate is largely stable, and that the flea on the elephant’s buttock that is humanity can have no effect. Yet if we were to imagine Earth as an onion, our atmosphere would be no thicker than its outermost parchment skin. Its breathable portion does not even completely cover the surface of the planet—which is why climbers on Mt Everest must wear oxygen masks. And the gases that comprise it are so insubstantial that more gas lies dissolved in the oceans than floats in the atmosphere, and more heat energy is stored near the ocean’s surface than in the entire great aerial ocean itself.

  To fully understand the atmosphere’s vulnerability we must recognise not only its size and gossamer substance, but its dynamism. The air you just exhaled has already spread far and wide. The CO2 from a breath last week may now be feeding a plant on a distant continent, or plankton in a frozen sea. In a matter of months all of the CO2 you just exhaled will have dispersed around the planet.1 Because of its dynamism, the atmosphere is on intimate terms with every aspect of our Earth, from the mantle upward. No volcano belches, no ocean churns—indeed no creature breathes—without the great aerial ocean registering it.

  There is one remarkable aspect of the great aerial ocean that has only recently been appreciated—its telekinesis. The last time you heard of telekinesis was probably when Uri Geller was bending spoons, but the term does have a valid scientific definition. It means ‘movement at a distance without a material connect
ion’, and in the case of the atmosphere telekinesis allows changes to manifest themselves simultaneously in distant regions. Thus, in response to heating or cooling, for example, our atmosphere can at once transform itself from one climatic state into something quite different. This allows storms, droughts, floods or wind patterns to alter on a global level, and to do so more or less at the same time. Telekinetic entities are powerful, but also exquisitely vulnerable to disruption. Our global civilisation is telekinetic, which is why it is such a force in the biosphere, but its telekinesis also explains why regional disruptions—such as wars, famines and diseases—can have dire consequences for humanity as a whole.

  The atmosphere is opaque to most forms of radiative energy. Most of us imagine that daylight is the only energy we receive from the Sun, but sunlight—visible light—is only a small band in a broad spectrum of wavelengths that the Sun shoots our way. Light is important to us, of course, for we are creatures of the day whose eyes have evolved to detect wavelengths in just that part of the spectrum. To other wavelengths, the atmosphere is as impenetrable as a brick wall, and it’s the gases making up part of that barrier that are the focus of this book: specifically the greenhouse gases, a collection of disparate molecules that share the ability to block long wavelengths of energy. We are more familiar with long wavelengths under the name ‘heat energy’, and heat is what these gases trap. By doing so, however, they become unstable and eventually release the heat, some of which radiates back to Earth. Greenhouse gases may be rare, but their impact is massive, for by trapping heat near the planet’s surface they both warm our world and account for the ‘upside down’ troposphere.