April 2025. Did Colossal bring back the dire wolf?
Short answer, not really.
The long answer is a bit more complicated and goes into what ‘species’ actually means.
Earlier in April, the biotech company Colossal put out a press release announcing the first de-extinction. They’ve genetically engineered a dire wolf out of extinction—and now, for the first time in 10,000 years, they’re back in their natural habitat (or so Colossal says).
De-extinction is the process of bringing back extinct species, or modern-day analogs to extinct species. This can be done through cloning DNA from preserved specimens or by gene editing their closest related surviving species to make them resemble their extinct kin. While this used to be an unlikely science-fiction dream, the development of CRISPR-Cas9 and other gene editing techniques has made it a possibility.
Colossal says their team used DNA sourced from a 13,000 year old tooth & 72,000 year old skull to analyze the dire wolf’s genome. They used this as the basis for their edits, which they carried out on three gray wolf embryos.
What is a species?
If you’ve taken a biology class, you’ve probably heard the term “species” tossed around before. The conventional definition of species is a group of organisms in which two individuals can reproduce & create fertile offspring. It’s generally a good rule of thumb definition, but there’s a lot of edge cases where the topic becomes muddy.
What happens when you look at critters that only reproduce asexually, like bacteria? What about cases where two species hybridize, and remain fertile?
These outlier cases have led some scientists to propose alternate definitions for species. Colossal’s Chief Science Officer (CSO) Beth Shapiro said in an interview with ABC:
“I think that the best definition of a species is if it looks like that species, if it is acting like that species, if it’s filling the role of that species then you’ve done it.”
This definition of species depends on its phenotype, behavior, and niche. A phenotype is a species’ physical expression of its genes. For instance, your eye color is a phenotype and is the observed effect of the genes behind your eye color. Shapiro said that their analysis of ancient dire wolf DNA suggested that they had light fur, which is why Colossal edited their gray wolf skins to be an eye-catching white. But instead of editing the pigment genes actually responsible for fur color, the team instead disabled two genes whose absence in dogs & other canids is known to cause a white coat. Colossal avoided the actual edits because they were linked to increased risks of deafness, blindness, and albinism—traits that the team didn’t want to take chances on.
What about behavior? Does the dire wolf behave like a real dire wolf? Well, they’ve been extinct for thousands of years, and we lack any actual evidence as to their behavior, so we can’t actually test that point.
What about their niche? A niche refers to the ecological role a species carries in its environment. For example, owls occupy the niche of eating small animals such as mice in woodland areas. The dire wolf was a carnivore that likely scavenged & hunted large megafauna. It was a species adapted for life in Pleistocene, and part of why it went extinct is thought to have been the extinction of its typical prey. If a dire wolf was to be de-extincted & rewilded today, it would be in unfamiliar territory—there are no more megaherbivores. Additionally, the three wolves Colossal has bred are living in a fenced-off lot and aren’t actively contributing to their environment.
Following Shapiro’s definition of a species, Colossal’s dire wolf checks the phenotype box but doesn’t meet the behavior/niche ones. Is that enough to consider it a species?
At the end of the day, the idea of what a species is is complicated. Ambiguity & argument around definitions like this can hold back science. This linguistic debate is no trifling matter—it can impact real world legislation and policy! For example, as soon as the news of Colossal’s ‘de-extinction’ broke, the Secretary of the Interior Doug Burgum tweeted out a statement suggesting that now that de-extinction technology is viable, the Endangered Species List is on the chopping block. De-extinction might be used to devalue the importance of conservation, instead shifting the mindset of preservation to one of “we can just bring them back!”
If you look at the news, you’ll notice a lot of the reporting around the Dire Wolf story focuses on the miracle of “listening to the howls of a dire wolf pup brought back from extinction for 10,000 years.” By focusing on the info that brings the best headline, science can sometimes be shifted out of focus.
Whenever new technologies come out, it’s important to approach them with a critical mind. What do you think defines a species? Do you think Colossal has revived the dire wolf?
Works Cited
https://evolution.berkeley.edu/evolution-101/speciation/defining-a-species/
https://x.com/SecretaryBurgum/status/1909345951069651032
Picture credit Colossal
