Biologists argue that modifying grey wolf cells to resemble prehistoric predators does not constitute a true de-extinction, according to an argument published in Biology Letters.
The distinction between reviving a species and altering existing genetic traits centers on evolutionary lineage. Marine biologist Andrew Davinack and biochemist Charlotte Daniels from Wheaton College Massachusetts put forward the case, focusing attention on the so-called “de-extinction” of the dire wolf by biotech company Colossal Biosciences in 2025.
By altering grey wolf cells, Colossal Biosciences managed to produce animals featuring traits more reminiscent of dire wolves, such as lighter fur, larger teeth, and bigger bodies.
That is actually not a de-extinction, Davinack and Daniels contest, and they have introduced a new term for the mistake of calling it one: lineage-genome conflation.
“Recent advances in ancient DNA sequencing, comparative genomics and genome editing have renewed interest in de-extinction, often framed as the technological reversal of species loss,” write the researchers in their published paper.
“Here, we argue that de-extinction cannot recover extinct species because extinction represents the termination of an evolutionary lineage, not merely the disappearance of genetic information.”
Lineage Termination Defines Permanent Loss
Some de-extinction methods are more befitting of the term than others, the researchers state. A species is more than its DNA. Genes and the physical characteristics they result in have been born from a long, continuous, evolutionary history. Any gaps in that history break the connection and redefine the species.
Then we have the issues of habitats and populations. Is it possible for a handful of modified creatures to successfully emulate the genetic diversity of a massive population or restore the ancient environment they once inhabited?
More than 10,000 years ago, those prehistoric predators navigated an environment vastly different from today’s world, meaning the dire wolves lived in circumstances that no longer exist. The climate, food sources, predators, and other environmental connections are no longer around in the modern day. That represents another break that makes the extinction permanent.
“Species are historically continuous population-level lineages shaped by gene flow, mutation, drift, selection, demographic history and ecological interaction,” write the researchers.
“A reconstructed genome, even if highly accurate, represents at most a partial snapshot of an individual organism.”
Researchers Urge Precise Terminology to Prevent Scientific Misrepresentation
The study’s authors note that professional researchers and their published studies generally exercise caution to avoid misapplying phrases like “de-extinction” when inappropriate. On the other hand, they appeal to media outlets and private enterprises to adopt greater accuracy and care when discussing technological milestones.
Terms like de-extinction can be misleading and misrepresent the science involved, the researchers argue. That confusion makes it harder to put technological progress and new techniques in context.
“Greater precision in terminology therefore has practical consequences,” write the researchers.
“Lineage restoration, genetic recovery, phenotypic reconstruction, ecological substitution and restoration of historical communities are distinct objectives and require different criteria of success.”
The researchers do not go as far as saying de-extinction is impossible. They contend that the dire wolves case does not qualify, while noting that using preserved cells or preserved embryos is a more promising route for de-extinction. That approach solves some of the problems mentioned above and ensures greater biological continuity.
Back in 2003, attempts to preserve cells were utilized on the Pyrenean ibex, and despite the creature failing to live, that project presents a far more credible basis for true de-extinction.
The authors make clear that they do not question the validity of the genetic engineering achievements accomplished by organizations like Colossal Biosciences.
What took place in 2025 was not the resurrection of an extinct species, but rather the creation of grey wolves carrying certain characteristics of dire wolves.
“Genomic reconstruction may recreate selected traits or produce ecological proxies, but it cannot recover extinct species as historically continuous evolutionary lineages,” write the researchers.
