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

weak with scurvy. By April of the following year, 24 more men had died. Sir John himself died in June of that year. The remaining 105 men abandoned the ships and headed on foot toward the mouth of the Great Fish River on the mainland. Many died along the way. For the crew who survived, Great Fish River turned out to be an unfortunate choice. It was such poor hunting ground that native Inuit avoided it. The men starved. Every last man who had set sail from Greenhithe five years earlier perished from tuberculosis, scurvy, or starvation.
    Back in England, years went by with no news of Sir John’s expedition. Lady Jane Franklin, Sir John’s wife, had commissioned many voyages to rescueher missing husband. After several unsuccessful attempts, explorer Francis McClintock set sail in 1857 and finally solved the mystery. Captain McClintock returned with relics of tin cans and old clothes, stories from the Inuit about the demise of the crew as they trudged across the ice, and a written record of the journey retrieved from King William Island with the date of Franklin’s death.
    McClintock narrated the details of his search expedition to the Royal Geographical Society on November 14, 1859, more than fourteen years from the time Franklin had set sail with his crew. In his report, McClintock repudiated Franklin’s earlier, overly confident claim, telling the gathering that it is “evidently an error to suppose that where an Esquimaux can live, a civilized mancan live there also.” With that, a chapter closed on Britain’s thwarted quest to sail across the northern Atlantic through an ice-free passage.
    My intent in relaying Franklin’s catastrophe is not to retell a well-known story or to dwell on the foibles of the brave explorers. Rather, it is to point to the key ingredient that makes our species different from others. Franklin’s crew and the Inuit belonged to the same species. But the shared ancestry did not provide Franklin and his crew with knowledge of survival tactics in the Arctic—how to hunt, build kayaks, and cooperate with the group to get through the winter. Nor did their parents and communities teach them these skills as they grew up in England.
    It’s no surprise that the British explorers lacked the right skills. The Inuit and British cultures were each built on an accumulation of knowledge passed from one generation to the next. Each culture fit the local surroundings. Culture—shared knowledge accumulated from experience—takes time and builds over generations. Franklin’s crew and the Inuit could not readily swap places, and a few years were not long enough for the unfortunate men to learn what the Inuit culture knew before starvation snatched away the chance. Given a longer time, more expeditions, a larger crew, or even more contact with the Inuit, perhaps they could have learned to adapt to the harsh Arctic conditions. For the Inuit, it took millennia of struggle to learn to survive in the severe climate.
    The prominent role of culture in human evolution has stumped the minds of many, including Charles Darwin. Darwin understood that his theory of natural selection would not stand up to scrutiny if he tried to argue that humans were an exception to the general rule. The theory explained what he had seen on the Galapagos Islands in 1835, where the distinct shapes and sizes of the finches had intrigued him as a young naturalist. It was simple and elegant, as it remains to this day. After ancestral finches arrived on the island from the South American mainland, some ate seeds and some ate insects. Those with blunt, strong beaks were more likely to survive by crunching seeds from the ground. Those with sharp, pointed beaks were more likely to survive by grasping insects on trees. Surviving ground-birds passed on blunt beaks to their offspring, and tree-dwelling birds passed on pointed beaks. Over time,ground finches and tree finches diverged into separate species. Inherited genes responding to the