Woolly mammoths are considered a prime candidate for de-extinction. Last year, researchers at McMaster University announced they had nearly sequenced the entire Wolly mammoth genome. George Teichmann/Yukon government
The potential for bringing back extinct animal species, known as de-extinction, is one of the hottest and most controversial topics in conservation biology today.
- COMING UP | Axel Moehrenschlager speaks with Quirks & Quarks on Saturday
The issue has divided some of the biggest names in science, with prominent backers like George Church, a professor of genetics at Harvard Medical School, and equally well known detractors, like Paul R. Ehrlich, a professor of population studies at Stanford University, all weighing in publicly on the subject.
The debate, in essence, can be distilled to a simple question: just because we can potentially revive extinct species, should we?
The answer is not as simple.
Axel Moehrenschlager, a biologist at the Centre for Conservation Research at the Calgary Zoo and an associate professor of biology at the University of Calgary, says that de-extinction is a fascinating possibility, but one that should be approached cautiously.
“There are potentially many issues in bringing a species back … But our primary concern is, if we were to bring something back, why are we doing it? Are we doing it because it’s something cool to do, or because it’s valuable for the ecosystem?” Moehrenschlager said an interview that airs on CBC’s Quirks & Quarks on Saturday.
Moehrenschlager was part of an international team of scientists that published a paper in March in the journal Trends in Ecology and Evolution that outlined 10 vital questions that scientists should ask before selecting candidate species for de-extinction.
“One of the things about species – when you put species back – is that they do things in that ecosystem and those things can potentially be useful or could be potentially damaging,” he says.
“In some cases bringing a species back could restore an ecological function that has been lost. But in other cases, in the wrong environment, it could make extinct species invasive and very damaging.”
According to Moehrenschlager, the most important question is, “is this reversible?” In other words, could we undo the reintroduction of a previously extinct species into an ecosystem? It’s a vital question because there may be risks associated with de-extinction that scientists cannot accurately predict.
“What if we bring back something that is actually an excellent vector for diseases, for example, that could affect livestock or other species or ourselves?” he says. “These are looming questions.”
The process of de-extinction requires using genetic material from an extinct species, and then splicing that DNA with the DNA of a close living relative, to produce offspring that can survive in the wild.
Last year, an evolutionary biologist at McMaster University in Hamilton, Ont., announced that his lab was on the verge of sequencing the entirety of the Woolly mammoth’s genome. Woolly mammoths have been extinct for at least 6,000 years, but the research may open to the door to cloning a living specimen, albeit one that also contains some DNA from modern elephants, a close relative.
The final product is an animal that is not wholly one species or another, but a new hybrid, which itself raises a whole set of new questions, says Moeherenschlager.
“What kind of organism is it? How do we classify it? How do you protect it? If you release it back into the environment, is it now an endangered species that deserves endangered species protection?” he asks.
On the verge
The de-extinction debate moved from labs and hallways of academic institutions and into the public gaze in March last year, at the TedXDeExtinction conference in Washington D.C., at which some of the field’s most progressive thinkers laid out the case for bringing long-lost species back.
Many scientists who attended the event made it clear that they believe de-extinction will be a reality within the next several decades. Indeed in 2009, a Pyrenean ibex – a species that went extinct in 2000 – was born in a laboratory. It survived for only seven seconds, dying of lung complications, but the reported findings rocked the world of conservation biology.
While the prospect of de-extinction is deeply fascinating and one that should be taken seriously by the scientific community, Moeherenschlager says, it shouldn’t detract from efforts to conserve the species that remain on Earth today.
“We are losing species at such an incredible rate that we need to act now … to make sure we don’t lose the treasure we already have on this planet. We shouldn’t be obsessed with things that have gone extinct in the past and ignore those that are still here.”