Eek, It's a Woolly Mouse! The First Step in Reviving a Prehistoric Mammoth Starts with Adorable Rodent (Exclusive)

Yahoo

04-03-2025

Scientists at the Dallas-based Colossal Biosciences have taken a big step towards their goal of bringing back the woolly mammoth by creating what they've dubbed Colossal Woolly Mouse
"I'm excited," Beth Shapiro, Chief Science Officer at Colossal, tells PEOPLE of the new mice, which have been genetically modified to have woolly mammoth traits
'In the next six months, we'll see if our woolly mice are actually happier in cooler environments, which is the predicted effects of these changes,' she adds
Behold, the woolly mouse.
Scientists at the Dallas-based Colossal Biosciences have taken a small step towards their goal of bringing back the woolly mammoth: Colossal Woolly Mouse.
"I'm excited," Beth Shapiro, Chief Science Officer at Colossal, tells PEOPLE, explaining that this is "really our first validation" that they actually can create living animals that have been genetically modified to have woolly mammoth traits.
"It's the first time that we've succeeded," she adds.
Like woolly mammoths, these mice have curlier hair — which is the same color of the mammoth mummies found in the permafrost — as well as a gene that should impact the way their bodies metabolize fat.
To be clear, there was not a prehistoric, or even historic woolly mouse. But, in order for the scientists to prove they were on the right track in the quickest possible time, they chose to perform the experiment with mice rather than actual elephants — which are the closest living relative to the woolly mammoth.
'Elephants have a 22-month gestation and then it takes another decade to reach sexual maturity," explains Shapiro, who pointed out that that's a "long time" to wait to see if their experiment would in fact lead to elephants having a woolly coat.
'It doesn't make any sense," she adds. But since mice only have a 20-day gestation, that made them a more ideal choice.
A unique feature of the mammoth are clumps on their back filled with fat to help keep the animal both insulated and energized during long, frigid months in largely barren landscapes.
The Colossal woolly mouse is the first living animal engineered to express multiple cold-adapted traits using mammoth gene orthologs (genes in different species that evolved from a common ancestral gene and normally retain the same function). As such, they represent a living model for studying cold-climate adaptations in mammals.
'In the next six months, we'll see if our woolly mice are actually happier in cooler environments, which is the predicted effects of these changes,' Shapiro says.
According to Colossal, their efforts — which ideally will result in creating a hybrid species that's virtually genetically indistinguishable from woolly mammoths — could also lead to breakthroughs in the fight against elephant endotheliotropic herpesviruses. EEHV is a highly-dangerous and fatal condition that wreaks havoc in young Asian elephants.
In addition to the mammoth, Colossal is working on two other "de-extinction" projects: bringing back the Dodo and the Thylacine, or Tasmanian tiger.
Along with Shapiro, Anna Keyte, who is leading the Dodo efforts, and Sara Ord, who is heading the Thylacine project, say it's difficult to explain to their families exactly what they do for a living. But they try to put it into terms that allow people to understand this is more than just making a real-life Jurassic Park or creating a new exotic pet.
Right now, Keyte is thinking a lot about the implications of bird flu, which has taken out some recovering populations of birds.
'It has been really bad for California condors, so one of the things we think about in our de-extinction pipeline is not only bringing back species we've lost, but making them resilient to the challenges of today,' she tells PEOPLE.
Ord notes that there is also perhaps a moral or ethical angle to bringing back species that were killed off through human interference.
The Thylacine, a carnivorous marsupial, was aggressively hunted to extinction in the course of about 100 years. The Australian government signed a species protection act in July 1936, but just two months later the last animal, commonly known as the Tasmanian tiger, died.
'It's an example of a human caused extinction," says Ord. "And so how responsible are we to bring back this species that we drove away?"
Related: One of the 'World's Rarest' Fish, Thought to Be Extinct, Rediscovered After 85 Years
The team leaders of the three de-extinction projects are all women, something you would not have seen in the scientific world even a few years ago.
Women have been underrepresented in STEM (science, technology, engineering and mathematics) for many years. Women remain underrepresented in STEM occupations, with two-thirds (65%) men and about one-third (35%) women. Between 2011 and 2021, the number of women in the STEM workforce increased 31%, from 9.4 million to 12.3 million. (National Science Foundation, 2022)
Shapiro tells PEOPLE she's been watching the proportion of women in the system grow.
'It brings a different set of viewpoints that we really need,' she says. 'We're trying to solve some of the hardest problems in biology. It is going to take that sort of diversity of experience, diversity of viewpoints. It's not just the technology that's going to make that happen.'
As for the woolly mice, where do they go from here?
'This is not a project that will go on indefinitely. It served a purpose of testing genotype to phenotype, which we got positive results,' says Ord.
But do not fear for the living mice, because there are plenty of takers once their work is done.
'The CEO Ben Lamm made the comment 'Don't let Sara know because she's going to be adopting all of them,' ' Ord says with a laugh. 'We all are not only passionate about the science, but passionate about the animals. And that holds all the way to the wooly mouse.'
Read the original article on People