Could we ever bring back mammoths like Nebraska’s Archie? (Image: Joel Sartore/National Geographic Creative)
WILL we see woolly mammoths grazing on a Siberian steppe anytime soon? Or chickens laying eggs with a dodo surprise?
When Beth Shapiro started writing How to Clone a Mammoth a few years ago, she could have had little idea how timely her “how-to” manual would be. Now, with a flurry of headlines in recent months about the “imminent” resurrection of the woolly mammoth, her timing looks impeccable. Already, news of mammoth genes cloned in living elephant cells has emerged from two research groups this year.
“De-extinction”, the preserve of proleptic fiction like Jurassic Park, and coined from that genre, is becoming real. Shapiro, a biologist who researches the mammoth and the passenger pigeon, gives us a clear and fascinating update.
For some, de-extinction means the literal resurrection of long-lost species through whole-genome cloning, while for others it’s about conferring the traits of extinct animals on closely related living species to create approximations.
Shapiro is in the second camp. As she says, we are never going to get back the woolly mammoth our forebears hunted, but science may help us build a proxy. The Herculean hurdles involved provide much of the book’s focus.
So how do you do it? First, there’s old-school, Dolly-the-sheep cloning, which involves taking a whole genome from the DNA of your target species and injecting it into an egg of a closely related species that is minus its nucleus, and coaxing it to develop. Ice is far better at preserving DNA than the amber of Jurassic Park, but only bits of the genetic sequence are likely to survive.
Then there is back-breeding, where you select the closest descendants to your desired creation and breed for traits most like those of the extinct animal. Clearly, having the right genes in the first place is crucial here.
Then there’s the deluxe version, with new gene-editing techniques like CRISPR, currently a hot topic. Harness these, and you no longer need a full ancient genome – just an idea of which genes confer what trait and where they sit. Cut and paste mammoth genes into the genome of its closest relative, the Asian elephant, and voilà.
So much for the how-to. A sceptical proponent, Shapiro poses other big questions. Why do it at all? Once done, what next? Where will the new beasts live? Are they endangered species or genetically modified organisms? Could they upset our ecosystems?
Researchers are working on these issues. A mammoth, for example, would already have a home – Pleistocene Park in Siberia, tundra turned to fertile grassland by Sergey Zimov of the Russian Academy of Science.
De-extinction is an exciting topic, but the book can be a little academic, although Shapiro explains complex molecular biology clearly. It really comes alive, though, when she describes her own expeditions, for example, hunting mammoth bones across Arctic tundra in rickety Russian helicopters – minus window glass, for smokers.
“Shapiro hunted mammoth bones over Arctic tundra in rickety helicopters minus window glass for smokers”
Shapiro handles the debates well, although I’d have liked more about the “benefits” of de-extinction. For example, some experts say repopulating Siberia with mammoth-alikes would refill a niche that would make the ecosystem flourish, and have a positive effect on global warming.
Who knows? Some of us just have a soft spot for mammoths. Mine dates to 2014 when Lyuba, a baby mammoth, visited London’s Natural History Museum from the Shemanovsky Museum, Siberia. Sadly, says Shapiro, the baby did not yield usable DNA.
Public appetite for mammoths – and de-extinction – is clearly immense, and Shapiro has received both fan and hate mail. Her book can only prove a great aid to informed debate.
Princeton University Press
This article appeared in print under the headline “A mammoth task”