An American science startup says its researchers have brought dire wolves back from extinction, but some scientists are pouring cold water on that claim.
The company announced its achievement alongside a statement from the secretary of the US Fish and Wildlife Service.
And the story has been featured in major media outlets.
It's being shared as a good news story in contrast to a lot of the bad news in the world.
But experts are arguing there's reason for scepticism about the hype — here's why.
Claims dire wolves have been 'de-extincted'
Colossal Laboratories and Biosciences says it has "successfully de-extincted" dire wolves.
"The successful birth of three dire wolves is a revolutionary milestone of scientific progress," the company said in a press release.
And it's been all over the news, with stories about the company in The New Yorker, Rolling Stone and WIRED, with the company's chief executive Ben Lamm even appearing on The Joe Rogan Experience podcast.
It was also the cover story in the latest issue of Time Magazine.
This hype has been fuelled by the company's keen references to the fantasy series A Game of Thrones, in which some characters have dire wolves as pets.
As it turns out, the creator of the popular series, George R R Martin, is an investor in Colossal Laboratories and Biosciences.
Martin is also a "cultural adviser" to the company, hence why this kind of imagery is part of the company's promotional material:
In fact, the press release for the company includes a whole document discussing the dire wolf's impact on pop culture — and it goes for 53 pages.
This wideranging document rattles off references ranging from Sergei Prokofiev's 1930s composition Peter and The Wolf to metal rock band Metallica to indie icon Bon Iver.
It name checks the Twilight Series, Teen Wolf and Jungle Book.
The paper even includes a list of celebrities who have named their children after wolves (Lauren Conrad and William Tell called their son Charlie Wolf Tell, in case you were interested).
How did they 'de-extinct' dire wolves?
Colossal scientists modified grey wolf genes, which they used to create embryos that were implanted into surrogates that gave birth to pups.
The modifications were based on analysis of DNA extracted from two dire wolf fossils:
- a tooth from Sheridan Pit, Ohio
- an inner-ear bone from American Falls, Idaho
"The team deeply sequenced the extracted DNA and used Colossal's novel approach to iteratively assemble high quality ancient genomes," the company said in a press release.
"Together, this data provided more than 500 times more coverage of the dire wolf genome than was available previously."
But, as pointed out in the Time Magazine article, this didn't mean sticking dire wolf DNA into the grey wolf's DNA.
We spoke to Emily Roycroft, of Monash University's Evolutionary and Conservation Genomics Research Group, to make sense of this.
"The company claims to have used a gene-editing technology to make 20 targeted changes to 15 different genes of the grey wolf," Dr Roycroft said.
"Five of the edits are in genes already known to produce light coats in grey wolves."
But are they actually dire wolves?
Colossal has been calling the wolves "dire wolves".
But Dr Roycroft wouldn't.
"This is a grey wolf with an edited genome, not a dire wolf," she said.
"The genetic edits may have given these wolves a lighter coat to look reminiscent of a dire wolf — but what makes a species is more than just skin deep.
"Extinct dire wolves are around 5.7 million years diverged from living grey wolves, and a lot of evolutionary and genetic changes happened across those millions of years.
"Editing a few genes of the grey wolf does not make a dire wolf.
"There are many other factors that make dire wolves unique, including an entire suite of genetic, epigenetic and behavioural differences that we don't currently understand.
"We have to ask, is modifying a living species to show superficial traits from an extinct relative really de-extinction?"
Nic Rawlence from the Otago Palaeogenetics Laboratory is also sceptical.
"What Colossal Biosciences have produced is a grey wolf with dire wolf-like characteristics. This is not a de-extincted dire wolf, rather it's a hybrid," Professor Rawlence said.
Many people commented on the company's social media posts questioning its use of the term "dire wolf" to describe the pups, prompting a response from the company.
"We refer to these animals as dire wolves because they embody the key morphological traits, behavioral characteristics, and ecological functions that defined the species," the company said in a post on X.
"They look like dire wolves, and express genes specific to dire wolves."
Dire wolves described as 'functionally de-extincted'
"To truly de-extinct something, you would have to clone it," Professor Rawlence said.
"The problem is we can't clone extinct animals because the DNA is not well enough preserved.
"Even if you sequence the genome, you can't extract DNA from extinct animals in long enough chunks like you could with a living animal.
"So the only way to 'de-extinct' an animal is to use the new synthetic biology technology [that allows scientists to] go and chop out a little bit of DNA and insert a new piece of DNA that effectively results in a genetic change."
In other social media posts, the company used terms such as "functional de-extinction", which it defined as "the creation of organisms that resemble and are genetically similar to extinct species, with engineered traits to help them thrive in the modern world".
"It's a functionally de-extinct dire wolf," it said in another post.
"And a massive step.
"It shares close resemblance and significant genetic similarity to dire wolves of the past."
Peer-review study is still coming
A social media thread with questions raised by Taylor McCoy, a palaeontology volunteer at the Carnegie Museum of Natural History, was viewed nearly 80,000 times on X.
He was wary of the company promoting its progress before a peer-reviewed study was published.
But this came from the company's promotional website, a press release and a bunch of discussion generated by media coverage.
Colossal has since responded to Mr McCoy's tweet saying a research paper is coming.
"We will be publishing a scientific paper that describes the two dire wolf genomes that we sequenced as well as what we've learned from those genomes about the dire wolf's evolutionary history," the company said.
"That paper will be released on bioRxiv and submitted for peer review."
How many 'dire wolves' are there?
The company has publicised the birth of three so-called dire wolves.
Two males named Romulus and Remus were born in October last year.
The third, a female named Khaleesi, was born in January.
Where are the 'dire wolves' being kept?
In a non-disclosed location somewhere in the US.
"The wolves are thriving on a [8 square kilometre] secure expansive ecological preserve that is certified by the American Humane Society and registered with [US Department of Agriculture]," the company said.
"Colossal employs 10 full-time animal care staff to support the wolves' physical and mental wellbeing."
It says the property will provide "lifetime care" for the wolves.
When did the real dire wolves go extinct?
About 13,000 years ago, scientists think.
This was probably because the animals that made up their diet — large herbivores like horses, bison and camels — either became extinct themselves or their numbers drastically declined in North America, Kieren Mitchell, Alice Mouton, Angela Perri and Laurent Frantz wrote in an article for The Conversation.
"The disappearance of their prey almost certainly drove the dire wolf extinct," the researchers wrote.
"In contrast, the more flexible and adaptable grey wolf can survive on a greater variety of food sources."
