How to Clone a Mammoth

by Shapiro, Beth

  A BRAND OF POSITIVISM

  Regardless of how feasible it really is, de-extinction has succeeded in forcing us—by “us,” I am referring here to scientists who hope, as I do, that our research will have a positive environmental impact—out of our comfort zones, exactly as Stewart Brand envisioned it would. Stewart, of course, would like to see de-extinction do more than that. His goal is for de-extinction is that it will become “a reframing of possibilities as momentous as landing humans on the moon was.”4 Certainly, if it does become possible to resurrect extinct species or to coax living species to express extinct traits, our perception of what it means to be “extinct” will change fundamentally. The most momentous change, however, will be in our attitudes toward living species—this, I believe, is what Stewart is referring to when he speaks of possibilities reframed. Suddenly, we will have the technical know-how to engineer sustainability into threatened populations. Will improving rather than protecting species become the new objective of biodiversity conservation? If we turn to the past to identify traits that can be used to improve the plight of living species, where will we draw the line between preventing versus reversing extinction? And will we care?

  This, I believe, is why people like me are so captivated by the idea of de-extinction. Not because it is a means to turn back the clock and somehow right our ancestors’ wrongs, but because de-extinction uses awesome, exciting, cutting-edge technology to take a giant step forward. De-extinction is a process that allows us to actively create a future that is really better than today, not just one that is less bad than what we anticipate. It is not important that we cannot bring back a creature that is 100 percent mammoth or 100 percent passenger pigeon. What matters is that—today—we can tweak an elephant cell so that it expresses a mammoth gene. In a few years, those mammoth genes may be making proteins in living elephants, and the elephants made up of those cells might, as a consequence, no longer be isolated to pockets of declining habitat in tropical zones of the Old World. Instead, they will be free to wander the open spaces of Siberia, Alaska, and Northern Europe, restoring to these places all of the benefits of a large dynamic herbivore that have been missing for eight thousand years. De-extinction is a markedly different approach to planning for and coping with future environmental change than any other strategy that we, as a society, have devised. It will reframe our possibilities.

  De-extinction will, of course, be risky. We don’t know and cannot predict every outcome of resurrecting the past. The conservation success stories of the present day prove, however, that taking risks can be deeply rewarding. Removing every living California condor from the wild was an extraordinarily risky strategy to preserve the species, but one that undoubtedly saved them from extinction. Restoring gray wolf populations to Yellowstone National Park was both risky and, to a degree, unpopular, but the park is now flourishing in a way that it had not since its establishment in 1872, when wolves and other predators were actively exterminated. Allowing deer, cattle, and other wild animals to take over abandoned land in Europe was touted as both crazy and dangerous, but these reestablished wilderness areas stimulated a widespread shift in attitudes toward wildlife. They inspired new policies aimed at protecting natural spaces and the species that occupy these spaces. How will the world react when the first genetically engineered elephants are strolling casually through Pleistocene Park?

  I can’t wait to find out.

  ACKNOWLEDGMENTS

  When I signed on to write this book several years ago, my goal was simply to answer the question that I have been asked repeatedly since my first days working with ancient DNA: “Is it possible to clone a mammoth?” I could not have predicted that the idea of de-extinction would become so popular—and such a seemingly realistic goal—over the course of the book’s creation. It has been both fascinating and exhilarating to be part of these early days of de-extinction research, both as a scientist and as a de-extinction storyteller. I am indebted to the many researchers and thought leaders who have been behind this wave of enthusiasm and, in particular, to Ryan Phelan and Stewart Brand of Revive & Restore, whose efforts to move de-extinction forward are unparalleled.

  Actually writing the book has been both more challenging and more fun than I thought it would be. I appreciate all of those who read early chapter drafts and provided critical feedback. David States, Jacob Sherkow, Alberto Fernández-Arias, George Church, Tom Gilbert, Tony Ezzell, and Molan Goldstein all provided comments, corrections, and criticism that helped to make this book better.

  I thank the team at Princeton University Press for their continuous encouragement and tireless enthusiasm for this book. Alison Kalett has been a wonderful editor throughout the process, a constant source of enthusiasm, and a pillar of support when necessary. Jessica Pellien has been a joy to work with, as have Katie Lewis, Quinn Fusting, Betsy Blumenthal, and the entire team. I am delighted to have had the opportunity to work with them all.

  I am grateful to Tyler Kuhn and Love Dalén for allowing me to take advantage of their superlative photographic skills. I’ve taken thousands of photos while working in the field, but none of them come close to exposing the raw beauty of the arctic landscape as theirs do. Thanks also to Mathias Stiller, Alberto Fernández-Arias, André Elias Rodrigues Soares, and Sergey Zimov for sharing their images. Each of their images reveal critical aspects of the de-extinction process that words are inadequate to describe.

  I am also indebted to the people in my lab at UC Santa Cruz, some of whom are mentioned in the preceding pages, for tolerating my partial absenteeism, in particular as the final deadlines approached. Many thanks, both for keeping the research going and for not spending all of our money while I wasn’t paying as close attention as I should have been.

  Finally, I am grateful to my large and extended family for their support and encouragement throughout this process. In particular, I would like to thank Ed Green, my partner both in life and in running our lab, for his encouragement, enthusiasm, and advice as the chapters came together, for the many days that he took over childcare so that I could spend those few extra hours in front of the computer, and, of course, for tolerating and even supporting the craziest of the de-extinction projects taking place in our lab. If it’s a boy, I promise to name the first unextinct pigeon after you, Ed.

  NOTES

  PROLOGUE

  1. Piers Anthony, The Source of Magic (Xanth) (New York: Ballantine Books, 1979).

  2. “A new organization, Revive and Restore, formed by the Long Now Foundation with the help of the National Geographic Society and advised by a group of respected scientists, has been created to examine the potential for a new branch of zoology: de-extinction.” Times (London), 8 March 2013, http://www.thetimes.co.uk/tto/opinion/columnists/benmacintyre/article3708288.ece.

  CHAPTER 2: SELECT A SPECIES

  1. Svante Pääbo, the director of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and the leader of an international project to sequence the complete genome of a Neandertal, wrote an editorial in the New York Times in which he argues that as sentient beings, Neandertals have the same rights as humans and should not be cloned. His op-ed, “Neandertals Are People, Too,” was published on 24 April 2014.

  CHAPTER 7: RECONSTRUCT PART OF THE GENOME

  1. This is one of the most fascinating and potentially the longest-lasting impact of the Technology Review report: ben-Aaron states that while elephants have fifty-six chromosomes, mammoths have fifty-eight. In fact, we have no idea how many chromosomes a mammoth has, and we are unlikely to know the answer until a high-quality version of their genome has been sequenced and assembled. Nonetheless, the “fact” that mammoths have fifty-eight chromosomes is widely reported on the Internet. I can only assume the source is ben-Aaron’s article, as no reference or citation is ever provided.

  CHAPTER 9: MAKE MORE OF THEM

  1. This article, “Re-Wilding North America,” appeared in the 18 August 2005 edition of Nature. Josh Donlan is listed as the article’s
only author, but a footnote points to a long list of notable conservation biologists including Harry Greene of Cornell University, Joel Berger of the Wildlife Conservation Society, Carl Bock and Jane Bock of the University of Colorado, David Burney of Fordham University, Jim Estes of UC Santa Cruz, Dave Foreman of the Re-wilding Institute, Paul Martin of the University of Arizona, Gary Roemer of New Mexico State University, Felisa Smith of the University of New Mexico, and Michael Soulé of the Wildlands Project.

  CHAPTER 11: SHOULD WE?

  1. TEDxDeExtinction was organized by Ryan Phelan and Stewart Brand of Revive & Restore. All of the presentations are available from the Technology, Education, and Development (TED) Web site and from http://tedxdeextinction.org/.

  2. Carl’s article was published in the April 2013 edition of National Geographic Magazine. In addition to his story, the feature includes some delightfully nostalgic photography by Robb Kendrick that depicts species that might be targets for de-extinction research.

  3. I realize I am being overly harsh here. There have been several good articles written about de-extinction over the last several years. Carl Zimmer’s work in National Geographic Magazine, which I mention above, is excellent. Also, Nathanial Rich wrote a thoughtful and nuanced piece about de-extinction in the 2 March 2014 edition of the New York Times Magazine that I think is among the best of what has been presented thus far about de-extinction.

  4. This quote is from Stewart’s “Point” in the “Point/Counterpoint” series in which he and Professor Paul Ehrlich agreed to participate. It was published on 13 January 2014 as part of Yale University’s Yale Environment 360.

  INDEX

  Illustrations are indicated with bold face

  Advanced Cell Technology, 137–38, 142

  Agenbroad, Larry, 86

  Allee effect, 180

  amber, DNA preserved in, 45, 51–54, 56–58, 60–61; laboratory process to collect, insert

  ancient DNA: age and survival of, 65–66; amber as source of, 45, 51–54, 56– 58, 60–61; applications of, 10–11, 54–56; authentication of, 56–57, 60, 62, 69–70; co-extraction of environmental DNA, 42–43, 63–64, 70, 194; contamination with modern DNA, 56–63, 69, 194; degradation of, 60–61, 64–65; dinosaurs as sources of, 61; environmental conditions and preservation of, 64–65, 70–71; evolutionary processes revealed by, 10–11, 54–55; extraction of, 51–53, 65–66, 70; fossils as source of, 61, 63– 70, 113–14; fragmentary nature of, 41– 42, 60–61, 96, 113–14, 194; genome sequencing and assembly of, 10–11, 39–44, 56–58, 69–70, 111–15; preservation of, 54, 57, 64–66, 70–71, 83–84, 91; survival of authentic and very old, 66–71

  animal welfare, 14, 152–53, 170–71, 172, 194–95

  Anthony, Piers, ix–x, 211

  Archer, Mike, 190

  artificial wombs, 152–53, 195

  aurochs, 100–105, 130–31

  autopsies, mammoth, 83–84, 90–91

  back-breeding, 100–108, 130–31, 185

  bantengs, 137–38, 143

  Barnes, Ian, 75, 98

  base-pairs, 40–41

  bears, 15, 26, 70, 167–68, 199

  beavers: giant, 3; reintroduction to Great Britain, 200–201

  behavior: as barrier to de-extinction, 31, 47, 172–73, 199; captive rearing and, 31, 47–48, 169–71, 176–79; captivity and, 146, 168–72, 179, 181, 183; environment and, 10–11, 100 (See also captivity and under this heading); genetic engineering and, ix–x, 179; genetics and, 28, 100, 102, 105, 136, 169, 178; as “hard-wired” instinct, 47, 178; as learned from social groups, 47, 49, 172–73, 179; observation as motivation of de-extinction, 20; and vulnerability to extinction, 5

  Belyaev, Dmitry, 170

  ben-Aaron, Diana, 127–29

  biodiversity: ancient DNA and, 55; de-extinction and, 9, 16, 130, 163–64; extinction and, 5–7, 159–63; as motivation for de-extinction, xi, 16, 30–31, 130, 163– 64; rewilding and, 159–63, 188

  biodiversity conservation, 16, 163–64, 193, 203, 206

  birds: California condor recovery project, 115, 175–81, 207; as candidates for de-extinction, 20–22, 50, 156; cloning and, 153–59, 191; extinction and, 15, 34. See also chickens; moas; passenger pigeons

  bison: Bison latifrons, 71; hybridization and, 28; in Pleistocene Park, 38–39, 164; re-wilding and, 160; steppe bison, 2–5, 10, 12, 28, 65, 68–69, 98

  Bolson tortoises, 160–61

  Brand, Stewart, 8–9, 48–50, 115, 184, 189–90, 192–93, 203, 205–6

  bucardos (Pyrenean ibex), 7–8, 48, 142–47, 182, 196

  Buigues, Bernard, 73–76, 84–85, 87, 90

  Buigues, Sylvie, 75

  California condors, 115, 175–81, 207

  camels, 3, 10, 160–62, 161–62

  candidate species for de-extinction: behavior as factor, 31, 47, 172–73, 199; bucardo as, 142; Cascade Mountains wolf as, 26–27, 30; costs as factor, xi, 14, 31, 48, 193, 196; dodo as, ix–x, 17, 22–24, 35, 42, 64, 197; generation time as factor, 50, 107, 177; habitat availability as factor, 17, 18, 26, 35–39, 47–48, 160, 184–85, 197–202; Lazarus frog as, 8; living, related species as factor, 11, 20, 30–31, 45, 47, 147; mammoth as, ix–x, 11–14, 38–39, 49, 71, 149–50, 151, 164–65; megafauna as, 24–25, 81–82, 160; moa as, 20–22, 31; passenger pigeon as, ix, 9, 16, 32–33, 37– 38, 49–50, 71, 115, 153, 178; recent extinction as factor, 15, 32, 142; Steller’s sea cow as, 46, 152, 194, 197; subspecies as, 27–30; technology development as fact, 39–47; Yangtze River dolphin as, 19–20, 24, 199

  captivity, 194; breeding in, 146, 169–72; captive rearing and behavior, 31, 47–48, 169–71, 175–79; and psychological stress, 169, 170, 172

  Carbon-14, 66–67

  Cascade Mountains wolf, 17, 26–27, 30

  cattle, 28, 102–3, 107; cloning of, 143. See also aurochs

  caves, DNA preserved in, 64–65, 70–71

  CERPOLEX (CERcles POLaires EXpédition), 73–74

  chestnut trees, American, 37, 205–6

  chickens, 58–60, 156–58

  chimeras, 157–58

  Church, George, 8, 49, 115–17, 125, 130, 133, 135, 140; joke, 164, 191, 196

  climate: benefits of mammoth reintroduction to, 165; as important for DNA preservation, 57, 64–66, 70–71, 83–84. See also climate change; habitat

  climate change: as cause of extinction, 1–5, 7, 191; as driving adaptation, 14–15, 205; as natural, 7

  clones: banteng, 137–38, 143; bucardo, 7, 142–43; congenital defects in, 8, 81, 142– 44; Dolly the sheep, 7–8, 44–45, 78–79, 81; following de-extinction, regulation of, 187; guar, 137–38, 142–43; human, 93–94; of pets as commercial service, 81; Promotea the horse, 81; Snuppy the dog, 81, 93–94

  cloning: ancient DNA and, 11; birds, 144, 153–56, 191; cell line generation and, 91– 93, 166; commercial applications of, 81, 156; congenital defects as a result of, 8, 81, 142–44; cross-species, 145; as de-extinction technology, 8, 141, 149–51, 166; germ cell transfer and, 154–58; of mammoths (announced or attempted), 8, 85–89, 92–95; of mice from frozen cells, 91–92; by nuclear transfer, 7–8, 44–46, 77–81, 78, 85, 88–89, 92–93, 127, 143–45

  cold: and preservation of DNA, 64, 68–71, 69, 81–84, 95–96

  cold tolerance: in elephants as requirement for engineering mammoths, 14, 46, 49, 100, 108, 131–32, 163–64; mammoth-specific hemoglobin, 55, 107– 8, 123, 124, 131, 133; Ucp1 gene and, 46

  condor, California. See California condors

  conservation: de-extinction as tool for, xii, 16, 163–64, 189–93; ecosystem management and, 201–2; funding for, 48, 196– 98; genetic engineering to enhance living species, 205–6; prioritizing living species, 195–97; public opinion toward, 48, 197, 207; rewilding as tool for, 187– 88, 202

  contamination of ancient DNA, 42–43, 56–58, 60–63, 70

  convergent evolution, 19–20

  Cooper, Alan, 84

  costs of de-extinction, ix, 9, 14–15, 48–49, 193, 195–97; DNA sequencing as expense, 110, 113, 135; managemen
t of de-extinct species, 48, 196; and species as candidates for, 31

  Creak, James, 126

  Crichton, Michael, 56

  CRISPR (clustered regularly interspaced short palindromic repeat) systems for genome engineering, 121–23, 123, 133–35

  Crister, John, 150

  Dalén, Love, 95–96

  de-extinction, ix–xii; back-breeding as means of, 99–107; behavioral aspects of, ix–x, 11, 168–71; cloning technology and, 141; and ecosystem restoration, 10, 12, 130–31, 205; effect on human population, 37–38; feasibility of, 25–26; in fiction, ix, 9–10, 45, 56, 112–13, 126–29; funding of projects, 48, 85–86, 195–97; and habitat revitalization, 15; management of resurrected species, 201–2; media and popular conceptions of, 125, 190–91; politics of, 203 (See also regulation under this heading); and public interest in conservation, 197–98; of recently extinct species, 32; and reconstruction of ancient DNA, 111–13; regulation of resurrected species, 181–87; risks of, xi, 188, 189, 201, 207; and species enhancement, 206–7; time frame for, xi–xii, 116– 17, 125, 177; wild, self-sustaining population as goal, 25, 47–48

  de-extinction technologies: back-breeding, 99–105; cloning, 11, 44–45, 77– 81, 145 (See also nuclear transfer under this heading); genome editing, 11, 45–46, 107– 8, 115–24; germ cell transfer, 79, 154–58, 182; nuclear transfer, 77–81, 144–45, 147 (See also cloning under this heading); synthesizing genomes, 109–15

  deforestation, as cause of extinction, 31–35, 180, 197–98

  Denisovans, 139