When I explain that I study the woolly mammoth, sooner or later (and usually right away) comes the question, “Are you going to clone a mammoth?” From childish excitement to real scientific interest, the idea of cloning a mammoth raises general enthusiasm.
Despite the fact that my research is not related to cloning a mammoth, I had to learn about the cloning efforts, so that I can answer the numerous questions.
Luckily, the book How to Clone a Mammoth: The Science of De-Extinction by Beth Shapiro was published last year. It’s essential reading for everybody interested in understanding the current state, future prospects, and all the challenges of cloning a mammoth.
Shapiro’s book was published at the same time as international headlines reported on the woolly mammoth genes being successfully inserted into elephant cells by Harvard geneticist George Church and his team. It was a media sensation similar to the one experienced in 2013 after the TEDxDeExtinction event and publication of Carl Zimmer’s National Geographic article, “Bringing Them Back to Life”.
“On March 16, 2013, “de-extinction” hit the headlines like only new wars, missing airplanes, or resurrected mammoths can.” (p. 189)
In How to Clone a Mammoth, Shapiro tries to merge the general (and personal) enthusiasm for de-extinction with all the challenges that science has to overcome to move de-extinction from science fiction to reality.
I appreciate that Shapiro is more on the skeptical end of the spectrum. She doesn’t underestimate the effort and doesn’t simplify any of the steps that need to be performed before we see the woolly mammoth roam the plains of Siberia.
In the first part of How to Clone a Mammoth, Shapiro describes how the scientific community moved from the early (naïve) idea of finding an outstandingly well-preserved sample and proper cloning by somatic nuclear transfer to creating a mammoth-like elephant by genome editing.
I think that one of the best parts of the book is the description of all the major mammoth discoveries, starting in October 1999 with the Jarkov mammoth, which was transported inside a 21,000-kilogram block of frozen dirt 300 kilometers across Siberia hanging off a helicopter.
The stories of other mammoths are similarly fascinating. For example, the Yukagir mammoth was exhibited at the 2005 World Expo in Japan and Japanese scientists managed to extract its nuclei and insert them in mice eggs. The mummified baby Ljuba thought us that what is preserved on the outside, doesn’t have to be preserved on the inside (meaning DNA).
“These mummies may appear to be very well preserved, but the high-acid environments cause considerable cellular damage and destroy naked DNA. That means that, while these mummies might appear – superficially – to be the most likely source of an intact cell suitable for cloning, their remains may actually be the worst place to look for such cells.” (p. 91)
Then there was an expedition organized by South Korean scientists and filmed by National Geographic that brought back a piece of skin, acquired in a risky maneuver inside a melting permafrost tunnel. And finally, in 2013, a mammoth was found with “a deep red substance suspiciously reminiscent of blood” in the permafrost under it.
Despite all these promising discoveries, none of them has got us any closer to cloning a mammoth. And according to Beth Shapiro, it never will.
“So, mammoth cloning is not going to happen. No intact genomes will have survived the 3,700 years since the last mammoth walked on Wrangel Island. No mammoth chromosomes will be found that are sufficiently repairable to transform the cells in which they are found into pluripotent stem cells. From my perspective, it doesn’t matter how many trips are made to deepest Siberia or how many tunnels are blasted into the permafrost. It’s just not going to happen.” (p. 99)
However, there is another way, genome editing. And as mentioned above, it’s already happening; mammoth genes have been inserted into elephant cells by George Church at Harvard. In the second half of the book, Shapiro thoroughly describes the procedure that is likely just happening – and that will be happening as the technologies are improving – behind the walls of the Church lab at Harvard.
Instead of making a mammoth clone, we will have to do with an elephant, genetically engineered to look and be like a mammoth. Is this enough? Shapiro argues that it is, as long as the pursuit of species resurrection doesn’t completely overshadow the ecological resurrection. According to Shapiro, it’s not about creating a creature that will have to be pampered by humans and kept in captivity forever. It’s about bringing back an animal that will be able to fulfill its ecological function.
“What I do imagine is the perfect arctic scene, where mammoth (or mammoth-like) families graze the steppe tundra, sharing the frozen landscape with herds of bison, horses, and reindeer – a landscape in which mammoths are free to roam, rut, and reproduce without the need of human intervention and without fear of re-extinction. This – building on the successful creation of one individual to produce and eventually release entire population into the wild – constitutes the second phase of de-extinction. In my mind, de-extinction cannot be successful without this second phase.” (p. 12)
I think that How to Clone a Mammoth is a good blend of theoretical introduction into the science of de-extinction. It contains technical parts describing the methodology that could be used to clone a mammoth, and it also thoroughly describes why it’s not easy and what obstacles will have to be overcome to get there. It also spends considerable time discussing what species could and should be brought back and if/why we should/shouldn’t bring them back.
It’s a very ambitious attempt to please everybody from broad public to scientists from the field and that’s something I consider a weak spot of the book. For me, as a scientist working with ancient DNA, it gets boring at some points. On the other hand, for a non-scientist it must be pretty overwhelming. I think that How to Clone a Mammoth is an excellent book, but it requires a reader who is interested in the topic and hungry for all the information that the book is filled with.
To wrap it up, if you are a huge fan of The Jurassic Park, if you can’t wait to buy your tickets to the Pleistocene Park or if you want to understand why there isn’t a live mammoth yet, go ahead and order How to Clone a Mammoth. If you want to skip the details, just click on the TEDxDeExtinction page and watch a few short videos, or have a look at the one-hour presentation by Beth Shapiro.