Leonello Calvetti / Stocktrek Imag / Getty Images / Stocktrek Images
Using the recovered DNA to ‘genetically resuscitate’ an extinct species – the central idea behind the jurassic park movies – could come closer to reality with the creation this week of a new company that aims to bring back woolly mammoths thousands of years after the last of the giants of the arctic tundra disappeared.
With $ 15 million in funding, George Church, a professor of genetics at Harvard, known for his pioneering work in genome sequencing and gene splicing, hopes the company, in the bold words of his statement press release, may usher in an era when mammoths return to the arctic tundra. ”He and other researchers also hope that a resurrected species can play a role in the fight against climate change.
Granted, what Church’s company Colossal is proposing would actually be a hybrid created using a gene-editing tool known as CRISPR / Cas9 to assemble pieces of DNA recovered from frozen mammoth specimens in that of an Asian elephant, the closest living mammoth. relative. The resulting animal – known as a “mammophant” – would look and likely behave like a woolly mammoth.
Some say reintroduced mammoths could help reverse climate change
Church and others believe the mammoth’s resurrection would plug a hole in the ecosystem left by their decline around 10,000 years ago (although some isolated populations remained in Siberia until around 1700 BCE). shoulder and would have weighed up to 15 tons.
Mammoths once scraped layers of snow so that cold air could reach the ground and hold the permafrost. After they disappeared, the accumulated snow, with its insulating properties, caused the permafrost to start heating up, releasing greenhouse gases, Church and others say. They argue that the return of mammoths – or at least a hybrid that fills the same ecological niche – to the Arctic could reverse this trend.
Love Dalén, professor of evolutionary genetics at the Stockholm Center for Paleogenetics, is skeptical of this claim.
“Personally, I don’t think it will have an impact, a measurable impact, on the rate of climate change in the future, even if it were to be successful,” he told NPR. “There is virtually no evidence to support the hypothesis that trampling very large numbers of mammoths would have an impact on climate change and that could just as easily, in my opinion, have a negative effect. on temperatures. “
South China Morning Post / South China Morning Post via Get
Techniques could be better used to help endangered species
But even if Colossal researchers can bring back mammoths – and it’s not certain – the obvious question is, should they?
“I can see some reasons to do the early stages where you tinker with cell lines and modify genomes,” says Dalén. “I think there is a lot of technological development that can be done [and] we can learn a lot about how to edit genomes, and it could be very useful for endangered species today. “
Joseph Frederickson, vertebrate paleontologist and director of the Weis Earth Science Museum in Menasha, Wisc., Was inspired as a child by the original jurassic park movie. But even he thinks the most important goal should be to prevent extinction rather than reverse it.
“If you can make a mammoth or at least an elephant that looks like a good copy of a mammoth that could survive in Siberia, you could do a lot for the white rhino or the giant panda,” he told NPR. .
Especially for animals that have “declining genetic diversity,” says Frederickson, adding older genes from the fossil record or entirely new genes could improve the health of those populations.
Speaking to NPR in 2015, Beth Shapiro, a paleogenetician at the University of California at Santa Cruz and author of How to clone a mammoth: the science of de-extinction, said categorically, “I don’t want to see the mammoths come back.”
“It will never be possible to create a 100% identical species,” she said. “But what if we could use this technology not to bring back mammoths but to save elephants?” “
Mammoths could disrupt existing ecosystems
Colossal’s expressed goal of allowing woolly mammoths to “walk the arctic tundra again” by the thousands also raises another ethical concern: although the mammoth’s extinction thousands of years ago left a void in the land. ecosystem, this ecosystem is probably now adapted, if less imperfectly, to their absence.
“There is a new normal that has been around for thousands of years that has adapted to the ever-changing climate,” said Frederickson. “Bringing back something that has all of the characteristics that would have thrived in the Pleistocene doesn’t necessarily mean it’s going to survive today, especially when you mix up the unknowns of other genes that work in a tropical animal in hot weather and then try to move it to a new environment. “
“There were plants and animals that lived alongside the mammoth that are now long gone or have declined significantly in range and just bringing the mammoth back won’t bring them back,” he says.
In a different sense, the question arises as to how mammoths might fit together.
“The mammoth ‘de-extinction’ project raises a huge ethical issue – the mammoth was not just a set of genes, it was a social animal, just like the modern Asian elephant,” said Matthew Cobb, professor of zoology at the university. from Manchester, told The Guardian in 2017. “What will happen when the elephant-mammoth hybrid is born? How will it be received by the elephants?
The six-year period would be exceptionally short
All of this, of course, assumes that the production of a mammophant is even possible. Colossal says he hopes to produce an embryo in six years. But with around 1.4 million individual genetic mutations separating ancient Asian elephant creatures, the task of splicing genes could prove to be a mammoth undertaking.
Perhaps an even bigger obstacle will be the development of an artificial uterus for the gestation of embryos. Even Church recognizes that it might not be that easy.
“Is this going to happen soon? The answer is absolutely no,” says Frederickson.
Dalén agrees that the six-year deadline is “exceptionally short”. “It sounds pretty ambitious,” he says.
But Church and his colleagues are not alone in their ambition. The idea of the extinction of mammoths has been around for some time and other groups, such as Revive & Restore, a California-based nonprofit that last year managed the very first clone of a Endangered species, the black-footed ferret, also worked on a mammoth-elephant hybrid.
The traditional scientific view is that our ancestors hunted the mammoth to extinction, with more recent theories indicating that habitat destruction at the end of the last ice age is the most important factor, but that humans always take part of it.
Frederickson believes this is one of the reasons the question of de-extinction – fueled by pop culture and scientific advances in the real world – is raised so frequently by patrons of the museum he runs. “I think that as humans we have a little bit of guilt within us, always knowing that we almost certainly contributed to this extinction event.”
“It can be a way to relieve us of this burden,” he says.