Scatter, Adapt, and Remember: How Humans Will Survive a Mass Extinction

by Newitz, Annalee

  Still, the trip changes year by year; grays are constantly tweaking their route. Twenty years ago, most of the grays migrated along a path that took them inside the Channel Islands, and closer to the coastal cities of Santa Barbara and Los Angeles. The problem was that they stuck to the shoreline too closely, often following it all the way into the shallow waters where they would become trapped. Grays have had similar problems getting lost in San Francisco Bay and Monterey Bay when they chart their course using what Harvey jokingly referred to as the “keep the shoreline on the left” method. But today, their routes take them outside the Channel Islands, and often outside San Francisco Bay too. “So they’ve figured it out,” Harvey said. They realized that more direct routes away from the coast would be faster and less dangerous, and passed that information on. Grays live for about 50 to 70 years, so these course corrections are taking place within the lifespan of a typical animal.

  More recently, Harvey and a National Oceanic and Atmospheric Administration (NOAA) biologist named Wayne Perryman have observed that grays are migrating later in the year, possibly because melting Arctic ice means they have to go farther north to find good grazing grounds. As a result, a faster route south is going to become more desirable to the grays as the years go by—they need to cut corners, as it were. But this longer route is also changing a lot more than their maps to the south. In 2012, observers were surprised to find a female gray and her very young calf swimming in San Francisco Bay. Given the age of the calf, Harvey and Perryman estimated that the gray had probably given birth en route to Mexico. She’d left the Arctic so late in the season that she wasn’t able to get there in time to have her baby. It’s possible that the melting Arctic ice will dramatically change the migratory cycles of the Pacific grays, altering the map that one generation of whales passes along to the next. This is another clue that the grays navigate their migratory routes by learning and memory—if the trip were somehow hardwired into their brains, they wouldn’t be able to shift its parameters every year depending on environmental conditions.

  Of course, some grays don’t manage to remember the route quite right—which is why, for example, those three grays got caught in the frozen Arctic in 1988 and had to be rescued by icebreakers. This leads Harvey to another big question. Why should the grays continue to migrate at all, as the thawing Arctic slowly becomes more habitable year-round? “It might get to a point when they don’t have to go, but the reality is that the water is still cold,” he mused. And staying warm in winter Arctic waters takes a lot of energy. He and his colleagues believe it’s worth it for the whales to swim all the way down to Mexico and save energy in the warm water, rather than not swimming but remaining in the cold water.

  This also helps to explain why juvenile whales make the journey down to Mexico, even though they are still too young to participate in the mating and calving that goes on in the lagoons. To get the most out of all the blubber they’ve been building up in summer, the young whales need to seek out warmer waters with their elders. But there’s another benefit, too. “Eventually, if you want to be part of the reproductive group, you need to know how to do the migration,” Harvey explained. “They are gaining knowledge, including reproductive knowledge, by making the journey.” It’s likely that the young whales are learning another survival skill along with the route south and then north again. When they arrive in Mexico they’re watching other grays reproduce. How whales learn to mate is a big question mark scientifically, but Harvey said it’s possible that they do it the same way they learn to migrate: through observation and memory.

  How the Gray Whale Came Back from Extinction

  Unfortunately, memory is no defense against the concerted efforts of ships full of people with harpoons and explosives. The descendants of the whales Scammon hunted still roam the waters of the Pacific coast, but their now-extinct relatives in the Atlantic weren’t as lucky. A large group of grays lived in the Atlantic for thousands of years, migrating from the Arctic to the Mediterranean. But historical evidence suggests that they succumbed to hunters in the eighteenth century. Today, there are only two groups of gray whales left. One, the eastern Pacific, or California-Chukchi group, whose migration we’ve talked about up to this point, contains perhaps 20,000–30,000 individuals. The other is a small, poorly understood group of roughly 200 individuals called the western Pacific or Korean-Okhotsk grays. These whales have a different migration route, along the coast of Asia. In summer they graze along coastlines in the Sea of Okhotsk off the coast of Russia, above Korea and Japan. Their calving grounds are off the coast of Korea.

  Both these groups would have gone the way of their Atlantic cousins if it hadn’t been for the rise of conservation groups in California during the early twentieth century. After the establishment of groups like the Sierra Club, which helped protect Yosemite National Park from development in the late nineteenth century, the burgeoning environmentalist movement began to think about protecting animals as well as environments. Even whalers like Scammon noted with unhappiness that the whales were going to be exterminated if hunting kept up at the pace he observed. Often, hunters would simply plow into the mating lagoons and slaughter the vulnerable mothers and calves, destroying the population’s ability to reproduce. Disturbed by the inhumanity of these hunting practices, and aware that grays weren’t particularly valuable as commodities, in 1949 the newly formed International Whaling Commission outlawed the hunting of gray whales. Since that time, many scientists believe that the eastern Pacific population has bounced back to what it might have been before whaling started. Others argue, based on genetic data, that it’s likely the original population before whaling was closer to 90,000 individuals.

  Regardless of what the original population was, marine biologists who study the whales seem to agree that the California grays have rebounded in an extraordinary fashion. Over the past 60 years, they’ve gone from near extinction to a healthy, diverse group capable of learning new migratory strategies to cope with changing conditions in the Arctic. Their growing population numbers stand in stark contrast to those of other whales, especially ones like the right whale, humpback, and blue whale that navigate their own great migrations every year. Several studies suggest that noise pollution in the water from radar, and human encroachment into their territories, may be disorienting these whales. This leaves them vulnerable to beaching, or injuring themselves by swimming straight into large ships.

  Grays were saved from extinction because humans chose to change their behavior. It’s possible that humans might save other whales from extinction, too, by changing our behavior in the same way. We could avoid using frequencies that whales prefer for their sonar. Or we could track whale migratory patterns using satellites—something that many scientists do already—and avoid creating shipping lanes near the areas where whales are making their journeys. Changing the way we use sonar is obviously more difficult than outlawing whale hunting. But it is certainly possible, and today’s gray whale population is a reminder that extinction is not inevitable for these massive sea mammals.

  There’s another reason grays are good survivors, though. Their migratory patterns keep them relatively safe and well fed. Few animals compete with them for food in their Arctic Ocean hunting grounds, which are vast and well stocked. Humpbacks, by contrast, feed in a small coastal area, which Harvey calls “a very compressed region.” If they can’t find prey in that region, humpbacks suffer. But the grays have found an enormous feeding ground where they can chomp on the seafloor during summer, as well as a protected place to mate in winter. And they’ve carefully charted a route between the two places that’s as safe as possible. Traveling along the coasts, their large bodies are generally hidden from predators by the sounds of the surf and the dirty, silty water they love. Their lack of sonar may mean that grays are more solitary, simple creatures than some other cetaceans. But this simplicity has helped them rebound from extinction, while whales with more complex communication and social structures are suffering.

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p; Still, the grays would never have made it this far without their ability to pass along a survival map from one generation to the next. As long as they keep learning new ways to survive the arduous Pacific coastal migration, the grays will endure.

  Always Coming Home

  Nomadic humans survived for thousands of years in a similar way, wandering across vast regions to find food and good seasonal weather. Many human tribal groups had traditions where they met once or twice each year for large gatherings, not unlike what the grays do when they converge in the Mexican lagoons. At these gatherings, nomadic humans would exchange gifts, pass on stories, and find people to marry outside their bands. Today, however, human survival can’t hinge on migratory patterns. Most humans live in settled communities and cities, and the knowledge we pass on to the next generation is infinitely more complex than a migratory route or information about where to find the most abundant food. We’ve learned so much that we need libraries and databases to augment our memories.

  Still, the grays have a lesson to teach us about the role of memory in survival. This struck me forcefully one afternoon in Monterey Bay, when I joined a whale-watching group in a small boat that fought its way over wind-whipped waves in search of the elusive migrating grays. The most adventurous of us made our way to the bow with our cameras, clinging to the railings and getting completely soaked by spray. We were joined by several large schools of porpoises. A group of four kept jumping out of the waves at the same time in graceful synchrony, as if trying to make it clear to the ridiculous monkeys who really belonged out here. But we kept scanning the horizon for grays, hoping to see their characteristic spouts. At last, just when we were about to retreat, we spotted one. The whale slid its blowhole just above the waves, most of its great bulk obscured by water and distance, and disappeared again. We all jumped up and down, pointing and forgetting to take pictures in our excitement. Just the sight of such a magnificent creature filled us with crazy awe, and all the sopping people in the bow started bonding and swapping stories of other amazing animals we’d seen. One person had seen a Bengal tiger in the wild, and another had been in Mexico to see the grays in their winter home. Nobody forgets these kinds of sightings because most of us, no matter how much we love urban life and civilization, also deeply love nature.

  Like grays, humans are good survivors because we’ve learned to find food and homes across a vast region of the planet. Also like grays, we’ve learned to traverse these territories in more efficient ways, responding to changes in the environment. We’ve figured out how to build cities that protect us better than villages did; we’ve passed along stories of how to survive best on what is still a dangerous planet. Sometimes, we’ve even changed our behavior to protect life-forms other than ourselves. As we turn to the next part of this book, about planning for the future, we’re going to remember the grays’ lesson: You’re always coming home, but the path to get there is going to change all the time.

  13. PRAGMATIC OPTIMISM, OR STORIES OF SURVIVAL

  IN THE PREVIOUS three chapters, we’ve zeroed in on strategies that have helped three different life-forms—humans, cyanobacteria, and gray whales—survive in extremely adverse conditions. We learned how an ancient tribe of humans, today called Jews, lived by scattering and founding new communities in the face of war and oppression. We explored how cyanobacteria’s ability to generate its own form of sustainable energy has made it perhaps the most adaptable life-form on Earth. And we followed a group of gray whales on their difficult migration down the eastern Pacific coast, a journey each whale has memorized in order to survive, and even to bounce back from extinction once humans agreed to stop hunting them. By passing along stories about these survivors, we learn what it would take for humans to survive, too. But some stories about survival are more helpful than others.

  In part two, we explored the role symbolic communication played in human evolution. Storytelling could be called the cultural backbone of human survival. There’s a reason that conquering armies often burn the books and libraries of their enemies. Extinguishing a people’s stories is a way of erasing their future. But when we remember those stories, they can steer us in a direction that leads away from death. In fact, stories about how humans might live in the future—sometimes known as science fiction—may be among the most important survival tools we have. We can use these stories as a highly symbolic version of the migration maps that gray whales pass on to the next generation. Futuristic stories offer possible pathways our species can take if we want our progeny to thrive for at least another million years.

  What Makes Us Want to Survive?

  One of the twentieth century’s greatest science-fiction writers, Octavia Butler, told Essence magazine, “To try to foretell the future without studying history is like trying to learn to read without bothering to learn the alphabet.” Butler grew up during the height of the space race in the 1950s, surrounded by hopeful stories about how humans would colonize the Moon, Mars, and beyond. But her life as the intensely shy daughter of a maid wasn’t exactly Forbidden Planet material. Butler’s mother was a widow who had no home of her own—instead, she and Butler lived in the home of her employers, a white family where Butler recalled visitors making casually racist remarks as if she and her mother weren’t in the room. As an adult, Butler always expressed great admiration for her mother’s tireless efforts to survive, to keep going, despite the many barriers in her way.

  Perhaps for this reason, Butler’s great gift as a writer was her ability to tell moving, realistic stories about how people would survive in futures far more harrowing and strange than anything that ever appeared on the Enterprise’s sensors in Star Trek. Still, she often joked that bad science fiction inspired the themes in her writing as much as growing up black in a white-dominated world. She penned her first short story after watching Devil Girl from Mars on TV late one night, and realizing that she could do better.

  The literary world would never put Butler’s work in a class with Devil Girl. Not only did she win many SF literary awards before her death, in 2006, including the Hugo and the Nebula, but she was the first SF author ever to win the MacArthur “genius grant” usually bestowed on fine artists and distinguished scientists. Ultimately, what makes Butler’s work mesmerizing is her incredible ability to help readers see the world from a perspective radically different from their own. In an essay for O, The Oprah Magazine, Butler recalled a formative experience. She visited a zoo with her elementary school class, and watched in horror as the other kids threw peanuts at a caged chimp, taunting him. As the animal wailed in frustration (and possibly madness), the young Butler realized she had more sympathy for this ape at that moment than she did for her fellow humans. She’d caught her first glimpse of humanity as it might look through alien eyes, and the experience left its mark on her imagination forever. “At age 7, I learned to hate solid, physical cages—cages with real bars like the ones that made the chimp’s world tiny, vulnerable and barren,” she wrote. “Later I learned to hate the metaphorical cages that people try to use to avoid getting to know one another—cages of race, gender or class.”

  Many of Butler’s novels can be understood as thought experiments in which she offers solutions to the problem posed by that group of children tormenting the chimp. At the heart of this problem are those metaphorical cages. Such cages can be more pernicious than steel bars, because they prevent humans from seeing what we have in common as members of a species in danger of going extinct. How can humans survive in the long term when we seem to be so good at building cages? What would it take to alter the course of humanity?

  These are the same questions that I’m asking in this book. We can only meet the challenges of surviving whatever the natural world throws at us by working together as a species in small and large ways. Before we understand the nuts and bolts of survival strategies, however, it’s important to take a short philosophical break and think about why we’re doing this in the first place. Why do we want to survive? What is it that makes life worth savi
ng? How do we hope to improve humanity over the next million years, and what would that look like?

  Using a few of Butler’s science-fiction novels, we can think about some possible answers to these questions.

  Surviving Is Always a Compromise

  Most of us want humanity to survive for a simple reason: We hope there’s a chance for our families and civilizations to endure and improve over the long term. The problem is that we have a hard time imagining what that would look like. We envision a far-future world full of people who look just like us, zinging around the galaxy in ships that are basically advanced versions of rockets. And yet, if history is any guide, the humans of tomorrow will be nothing like us—their bodies will have been transformed by evolution, and their civilizations by the kinds of culture-changing events that have already marked human history. In her trilogy of novels called Lilith’s Brood, Butler dramatizes why some people choose death over survival. They are not prepared to deal with the radical changes required to bounce back from extinction. Still, Butler’s story offers us hope for humanity’s survival, and a new way of thinking about how we’ll do it.

  When Lilith’s Brood opens, a civilization of bizarre, tentacle-covered aliens called the Oankali have just kidnapped the tattered remnants of humanity after a nuclear apocalypse. Unlike humans, who evolved to use machine technology, the Oankali’s entire civilization is based on biology. They journey through the galaxy in living spaceships the size of planets, and every part of their environment—from their tree homes to their sluglike cars—is alive. They’re an ancient species who have dealt with many alien cultures, and they view humans as a fascinating anomaly: We’re intelligent creatures who live hierarchically. Apparently this is an incredibly rare combination in the universe, and they suspect it’s what led to our downfall. Luckily, as a representative of the Oankali explains to the protagonist, Lilith, they’ve preserved the few remaining humans in stasis pods while the Earth returns to a healthy state of nature.