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Exploring De-Extinction

Kayt Sukel

Thanks to advances in molecular biology, it might soon be possible to bring back species from extinction. But should we? Last week’s DeExtinction conference explored this idea in detail. Learn more...

What if scientists could use cloning or gene-based techniques to bring back extinct species like the woolly mammoth or the passenger pigeon? It sounds like something out of a science fiction novel, but Stewart Brand, author of Whole Earth Discipline: An Ecopragmatist Manifesto, introduced the idea of “de-extinction” in a 2013 TED talk.

Stewart Brand and Ryan Phelan hosted the TEDx DeExtinction conference. Source: Livestream

This past week, Brand’s non-profit organization Revive and Restore along with National Geographic and TED hosted a day-long conference called TEXxDeExtinction where biologists, geneticists, and conservationists discussed the reasons, methods, and ethics associated with this idea.

“We should be talking about de-extinction. We need to be talking about de-extinction because it’s already happening,” said Carl Zimmer, a science writer and speaker at the event. “It’s analogous to genetic engineering. In the 1970s, it became clear that we were looking at a really new sort of technology and needed to hash out the issues—even if they were confusing. This was a high-level discussion, but it was the first real public discussion of the issues surrounding species revival.”

Speakers included Alberto Fernández-Arias, the head of the Service of Hunting, Fishing, and Wetlands in Spain, who oversaw the first de-extinction attempt in 2003, which was designed to counter the extinction of Capra pyrenaica pyrenaica, also known as the Pyrenean ibex or bucardo. In addition, Michael Archer, director of the Evolution of Earth and Life Sciences group at the University of New South Wales, discussed ongoing cloning work in extinct species of frogs.

Kate Jones, chair of ecology and biodiversity at University College London, Beth Shapiro, an evolutionary biologist at the University of California, Santa Cruz, and David Ehrenfeld, a biologist at Rutgers University, debated the "why’s" and "why not’s" of the issue. And then Robert Lanza, chief scientific officer at Advanced Cell Technology, and George Church, a geneticist at Harvard Medical School, chatted about cloning, stem cells, and allele replacement techniques that may be used for de-extinction in the future.

Critics of de-extinction argue that it is not a viable solution because it does not address the biological and environmental issues behind why a particular species becomes extinct. These critics see de-extinction as a distraction from more traditional conservation biology.

For example, the bucardo in Spain, cloned from frozen tissue and born to a goat surrogate, is the first de-extinction on record (1). But the animal died 10 minutes later—a common occurrence in cloning experiments. Many argue that de-extinction is simply not practical due to the cost and uncertain outcome.

“These are pretty compelling points,” said Zimmer. “I think advocates of de-extinction are going to have to better articulate the reasons why we should be doing this before it become a reality.”

Still, Zimmer argued the event provided a strong platform to both educate the public about de-extinction as well as explore some of ethical and scientific issues at play. “There are some amazing new technologies out there with potential for conservation biology. We haven’t started to think about what they mean—and we’re only just starting to familiarize ourselves with what we could do with them. Then, from there, we have to figure out what we should do with them,” he says. “This is a start.”


  1. Folch, J., M. J. Cocero, P. Chesné, J. L. Alabart, V. Domínguez, Y. Cognié, A. Roche, A. Fernández-Arias, J. I. Martí, P. Sánchez, E. Echegoyen, J. F. Beckers, A. S. Bonastre, and X. Vignon. 2009. First birth of an animal from an extinct subspecies (capra pyrenaica pyrenaica) by cloning. Theriogenology 71(6):1026-1034.

Keywords:  genomics deextinction