The Big Ratchet: How Humanity Thrives in the Face of Natural Crisis by Ruth DeFries Read Free Book Online

well-known hatchet is the extinction of the dinosaurs about 65 million years ago. Another occurred 250 million years ago and wiped out ninety-six out of every hundred plant and animal species. What caused these extinctions is not exactly clear. Spates of volcanic activity might have raised temperatures from the carbon dioxide or rained down sulfur-laden acid. Perhaps impacts from meteorites spewed dust into the air and blocked light, the likely explanation for the dinosaurs’ death knell. Although these events were devastating, they also created opportunities. With the reset button pushed on the evolutionary trajectory, less dominant groups got a new chance. Were it not for the extinction event that spelled the end of the dinosaurs’ reign, for example, mammals may not have come to be a dominant life form on the planet.
    No amount of human ingenuity could re-create the diversity of species. From the inner workings of photosynthesis to the webs of energy-exchanging plants and animals, even the most sophisticated computers cannot mimic the complexities. The result is an amazing endowment from nature, ripe for human ingenuity’s grasp, as we select those species that are useful, tweak those that are not quite right for our needs, and even destroy those that are harmful. But humanity cannot create new species from the building blocks of life, at least not yet. This is another foundational feature of the planet on which we depend for survival, but over which we have no control.
    The basic foundations for our success as a species are far beyond our reach. The nonnegotiable conditions for the rise of humans on theplanet and our prominence today rest on long-term geologic features and an evolutionary history that we did not shape. We cannot alter the magnet in a planet’s core, churn the wheel of plate tectonics, or push a planet into a Habitable Zone. We cannot re-create the diversity of life. We cannot restage the physics and chemistry that governed the early Earth, or the biology that came later. But there is still plenty of leeway. The story that leads to the Big Ratchet is about the manipulation of those shorter-term features of our amazing planet, the features that we can control. The planetary platform provides the opportunity. Human culture provides the ingenuity.

3: ENTER HUMAN INGENUITY
    O N THE 19 TH OF M AY , 1845, the HMS Erebus and the HMS Terror set sail from Greenhithe, England. The Lords of the Admiralty of the United Kingdom had charged the leader of the expedition, Sir John Franklin, with finding the Northwest Passage, the elusive and much-sought navigable path linking Europe and Asia through the icy northern seas.
    This was Franklin’s fourth trip to the Arctic. He had experienced the treachery of the icebergs; the dark, cold winters; and the danger of starvation. Despite the prejudices of the times and the common presumption of British superiority over native cultures, Franklin knew that the Inuit were experts at surviving the Arctic’s stark winters. He was prepared to go outside the norms of British culture, to eat seal blubber and hunt walrus, if provisions ran bare. Before setting forth on the Erebus and Terror , Franklin remarked with confidence, “Where Esquimaux do live out a fair period of life, it is but reasonable to suppose that Europeans may subsist andsurvive for many years.”
    The expedition set sail with 132 crewmen and officers. Provisions included 16,884 pounds of biscuits, 2,490 gallons of ale and porter,15,664 pounds of preserved meat in tin cans, 6,859 pounds of sugar, 1,608 pounds of butter, 500 pounds of mustard, and 100pounds of pepper. The men crossed the Atlantic and spent the first winter docked at Beechey Island above the Arctic Circle. Pneumonia claimed the lives of three crewmen that winter.
    As winter thawed in 1846, the Erebus and Terror sailed southward toward King William Island. Somewhere along the way, the ships became snarled in ice. Provisions dwindled. The crew grew