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Science

De-Extinction: Reviving Species or Editing Look-Alikes?

Jayden

Analyzes global supply chains, industrial policy, and technology issues.

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Key points

  • In April 2025 Colossal Biosciences presented three pups — Romulus and Remus, born October 2024, and Khaleesi, born January 2025 — as de-extinct dire wolves. That is a company announcement: the underlying genome analysis had not been peer-reviewed at the time.
  • The procedure itself is consistently reported and not seriously disputed: 20 edits across 14 genes in gray wolf cells, introducing about 15 dire-wolf-inspired variants, using ancient DNA from a roughly 13,000-year-old tooth in Ohio and a 72,000-year-old inner-ear bone in Idaho, with domestic dogs as surrogates.
  • A 2021 Nature study found dire wolves split from the lineage leading to living wolves and coyotes about 5.7 million years ago with no evidence of interbreeding, and proposed a separate genus, Aenocyon — a gulf that 20 edits does not close.
  • The IUCN's 2016 guidance calls such animals proxies, not facsimiles, and Colossal's own chief science officer conceded that genetic identity with an ancient dire wolf is neither possible nor the goal.
  • The defensible upside is narrower than the headline: the same platform was used to clone four red wolves for genetic rescue. The downside is documented too — a 2017 study modelled net biodiversity loss through opportunity cost, alongside moral hazard and ecological uncertainty.

In April 2025, a Texas biotech company put three white-furred pups in front of the world's cameras and said something no company had said before: the dire wolf, an Ice Age predator gone for more than 12,000 years, was back. Colossal Biosciences named the males Romulus and Remus, born in October 2024, and a younger female, Khaleesi, born in January 2025, and described all three as de-extinct dire wolves [source: TIME, 2025]. The images traveled fast. So did the pushback. Within days, geneticists and paleontologists were arguing that what the world had actually met was not a resurrected species but a gray wolf with a handful of edited genes — a look-alike, not a return [source: Scientific American, 2025].

That gap, between what was announced and what was demonstrated, is the real story of de-extinction in 2026. The science of reading ancient DNA and rewriting living genomes has advanced fast enough to make "bringing back" extinct animals sound plausible. Whether that phrase describes what is happening — and whether it would help or hurt the living world — is a separate question, and a contested one. This article keeps three lines sharp throughout: what companies claim, what has been independently verified, and what outside experts actually say.

Table of Contents

  • Why de-extinction is back in the headlines
  • What Colossal did — and what it claims
  • Is it really a dire wolf? The definitional dispute
  • The conservation case for de-extinction tools
  • The moral hazard and the ecological risks
  • What to watch

Why de-extinction is back in the headlines

De-extinction is not a new idea, but it has never had a moment quite like this one. Colossal Biosciences, founded in 2021 by entrepreneur Ben Lamm and Harvard geneticist George Church, was built around a headline goal — recreate the woolly mammoth — and has since added the thylacine (the Tasmanian tiger) and the dodo to its list of targets [source: TIME, 2025]. The company says it is aiming for a mammoth calf by 2028 and has reached a valuation of roughly US$10.2 billion, an unusually large sum for a venture whose flagship products do not yet exist [source: TIME, 2025].

The dire wolf announcement is what turned a long-running research program into a global argument. Part of the reason is cultural: the dire wolf is familiar to millions as a creature from fiction, and one of the pups was named Khaleesi. But the deeper reason is that the announcement forced a question the field had mostly discussed in the abstract. If you edit a living animal to resemble an extinct one, at what point — if ever — can you say the extinct one is back? That is not a marketing quibble. It shapes how the public understands conservation, how regulators treat these animals, and how billions of dollars in scientific attention get spent.

What Colossal did — and what it claims

Here the layers matter, because the procedure is more modest than the headline. Working from ancient DNA — recovered from a roughly 13,000-year-old tooth found in Ohio and a 72,000-year-old inner-ear bone from Idaho — Colossal's scientists identified genetic differences between dire wolves and gray wolves, the closest living relative they worked from [source: TIME, 2025]. They then made 20 edits across 14 genes in gray wolf cells, introducing about 15 dire-wolf-inspired variants, and brought the resulting embryos to term in domestic dogs used as surrogates [source: Scientific American, 2025]. No ancient dire wolf gene was inserted whole; the team rewrote existing wolf DNA to match what it inferred a dire wolf carried [source: TIME, 2025].

The distinction between claim and verified fact is the crucial one to hold. The step-by-step procedure — the edit count, the ancient samples, the surrogates — has been consistently reported and is not seriously disputed. What has not been independently verified is the framing built on top of it. Colossal's underlying genome analysis, including its statement that dire wolves and gray wolves share about 99.5% of their DNA, had not been published in a peer-reviewed journal at the time of the announcement [source: The Scientist, 2025]. In science, an unpublished company analysis is a claim awaiting scrutiny, not a settled result — a difference the celebratory coverage often blurred.

The company has been more careful in its own words than the headlines suggest. Colossal's chief science officer, Beth Shapiro, acknowledged that "to make something that is genetically identical to an ancient dire wolf through gene editing is not really possible," and said that exact identity "is also not the goal" [source: Scientific American, 2025]. The aim, in the company's telling, is a functional version of the animal — something that looks and behaves like a dire wolf — rather than a genetic twin.

Is it really a dire wolf? The definitional dispute

This is where independent experts diverge most sharply from the marketing, and the disagreement is not merely semantic. It turns on how distinct the dire wolf actually was. A 2021 study in Nature found that dire wolves split from the lineage leading to living wolves and coyotes about 5.7 million years ago and showed no evidence of interbreeding with them — a divergence so deep that the authors proposed placing dire wolves in their own genus, Aenocyon [source: Nature, 2021]. By that account, the dire wolf was not a close cousin of the gray wolf but the last of an ancient New World lineage that merely resembled a wolf.

Set that against 20 edits in 14 genes, and the objection becomes clear. Jacquelyn Gill, a paleoecologist at the University of Maine, put it bluntly: "This is a designer dog. This is a genetically modified gray wolf" [source: Scientific American, 2025]. Her point is not only about numbers but about what a species is. "I have more than 14 Neandertal genes in me, and we wouldn't call me a Neandertal," she said, arguing that a species is more than a short list of edited traits — it is also behavior and ecology learned and transmitted across generations, none of which a lab can edit in [source: The Scientist, 2025].

Colossal's defenders answer on different ground. Shapiro has said that if an animal "looks like a dire wolf and acts like a dire wolf, I'm going to call it a dire wolf," a functional definition that prizes outcome over ancestry [source: The Scientist, 2025]. There is even a formal vocabulary for this middle position. The International Union for Conservation of Nature (IUCN) uses the word "proxy" — a substitute that represents an extinct form phenotypically, behaviorally, or ecologically — and deliberately prefers it to "facsimile," which would imply an exact copy [source: IUCN, 2016]. Read through that lens, the pups are best described not as resurrected dire wolves but as edited proxies: animals engineered to stand in for a function, not to reproduce a genome.

The conservation case for de-extinction tools

Strip away the dire wolf branding and a more defensible claim remains: the tools built for de-extinction may help species that are still alive. The clearest example arrived alongside the wolves. Colossal said it had cloned four red wolves — the most endangered wolf in the world, whose captive population has been squeezed through a severe genetic bottleneck — using the same platform, and framed the work as recovering "lost genetics" for a living species [source: Scientific American, 2025]. Shapiro described this as "actually using technology to prevent species from going extinct," and it is the part of the program that draws the least objection [source: Scientific American, 2025].

The logic is real. Many endangered populations suffer from low genetic diversity, and cloning or gene editing could, in principle, reintroduce lost variation — a strategy conservationists call genetic rescue. The ancient-DNA analysis, cloning, and multiplex editing that Colossal has developed for its extinct targets are the same techniques that a genetic-rescue program would need. In March 2025 the company reported a "woolly mouse," a rodent edited across several genes tied to hair and fat metabolism as a proof of concept toward the mammoth — though that work was posted as a preprint and had not been peer-reviewed [source: MIT Technology Review, 2025].

Even sympathetic experts add caveats. The conservation payoff for editing charismatic extinct megafauna, as opposed to helping living species, remains speculative; a mammoth proxy would inhabit a world that has changed for 4,000 years. The honest version of the conservation case is narrow but genuine: the techniques could strengthen genetic rescue for endangered animals, and that is a different, more modest promise than resurrecting the dead.

The moral hazard and the ecological risks

Against the upside sits a set of risks that conservation biologists have flagged for years. The first is financial. A 2017 study in Nature Ecology & Evolution modeled what happens when limited conservation budgets are spent on de-extinction, and concluded that even under optimistic assumptions — with resurrection externally sponsored — publicly funding these programs would leave fewer living species conserved, a net biodiversity loss through opportunity cost [source: Nature Ecology & Evolution, 2017]. Money and attention are finite; every dollar and headline has a next-best use.

The second risk is subtler and is often called moral hazard. If the public comes to believe that extinction is reversible — that anything lost can later be rebuilt in a lab — the urgency of protecting what still exists may quietly erode. The IUCN's guidance on proxies warns explicitly against this techno-fix framing, cautioning that the perception of a reversible extinction could undermine support for preventing extinctions in the first place [source: IUCN, 2016]. De-extinction, in this view, risks selling an insurance policy that does not actually cover the loss.

The third risk is ecological. Releasing an engineered proxy into the wild is not the same as restoring a species, because behavior and ecological fit cannot be edited into a genome. The independent paleogeneticist Kevin Daly, commenting on the mammoth work, cautioned that such an animal "won't be 100% mammoth," that its behavior cannot be predicted without the developmental and social context a species normally provides, and that it would be "hubristic to think we might have a complete grasp" of the environmental effects of a reintroduction [source: MIT Technology Review, 2025]. A proxy dropped into an ecosystem it never evolved for is an experiment with living variables.

What to watch

De-extinction in 2026 sits on a genuine scientific advance wrapped in a contested claim. The gene editing is real, the ancient-DNA analysis is real, and the potential to strengthen genetic rescue for endangered species is real. What remains unproven is the headline — that an edited proxy amounts to a resurrected species — and the framing carries risks, from misspent conservation funds to a public that files extinction under "reversible."

A few things are worth watching from here. Will Colossal's underlying genome analyses clear independent peer review, and will the results survive it? Will the same platform deliver measurable gains for living endangered species, such as the red wolf, or stay anchored to charismatic extinct headliners? Will regulators and scientific societies settle on shared language — "de-extinction" versus "proxy" — that tells the public what these animals actually are? And will any of these engineered animals ever be released into an ecosystem, with the ecological monitoring that would demand? The most useful habit a reader can carry is the one this field keeps testing: separate the announcement from the evidence, and the look-alike from the thing itself.

Charts

Scale of the edits made to gray wolf cells

Scale of the edits made to gray wolf cellsGenes edited 14count, Edits made 20count, Dire-wolf-inspired variants introduced 15count14countGenes edited20countEdits made15countDire-wolf-inspired variants introduced
These three counts describe one procedure, not three separate results: 20 edits distributed across 14 genes, introducing about 15 variants inferred from ancient dire wolf DNA. No ancient dire wolf gene was inserted whole — existing wolf DNA was rewritten.Scientific American (2025-04-08) (opens in a new tab)

Age of the ancient DNA samples used

Age of the ancient DNA samples usedTooth, Ohio 13,000years, Inner-ear bone, Idaho 72,000years13,000yearsTooth, Ohio72,000yearsInner-ear bone, Idaho
The two specimens that supplied the ancient DNA. Sample age is not the same thing as the lineage split — the 2021 Nature estimate puts that divergence about 5.7 million years back, on a scale this chart cannot show.TIME (2025-04-07) (opens in a new tab)

Timeline

  1. The IUCN Species Survival Commission publishes guiding principles on creating proxies of extinct species, preferring "proxy" to "facsimile" and warning that a perception of reversible extinction could undermine support for preventing extinctions.

    IUCN SSC (opens in a new tab)
  2. A Nature Ecology & Evolution study models limited conservation budgets spent on de-extinction and concludes it could leave fewer living species conserved — a net biodiversity loss through opportunity cost.

    Nature Ecology & Evolution (Bennett et al.) (opens in a new tab)
  3. Colossal Biosciences is founded by entrepreneur Ben Lamm and Harvard geneticist George Church around the goal of recreating the woolly mammoth; the thylacine and dodo are added later.

    TIME (opens in a new tab)
  4. A study in Nature reports that dire wolves diverged from the lineage leading to living wolves and coyotes about 5.7 million years ago with no evidence of interbreeding, and proposes the separate genus Aenocyon.

    Nature (Perri et al.) (opens in a new tab)
  5. The male pups Romulus and Remus are born, carried to term by domestic dog surrogates (company account).

    TIME (opens in a new tab)
  6. The female pup Khaleesi is born (company account).

    TIME (opens in a new tab)
  7. Colossal reports gene-edited "woolly mice" as a proof of concept toward the mammoth — posted as a preprint, not peer-reviewed.

    MIT Technology Review (opens in a new tab)
  8. TIME reports the announcement: three pups presented as de-extinct dire wolves, alongside the company's roughly US$10.2 billion valuation and its 2028 target for a mammoth calf.

    TIME (opens in a new tab)
  9. Scientific American publishes the counter-case — a gray wolf with edited genes, not a resurrected species — and reports the cloning of four red wolves on the same platform.

    Scientific American (opens in a new tab)
  10. Colossal marks the first birthday of Romulus and Remus in a company press release.

    Colossal Biosciences (press release) (opens in a new tab)

Analysis

Three layers, and the whole argument lives in the gap between them

Almost every disputed sentence about the dire wolf pups belongs to one of three layers: what the company announced, what has been independently verified, and what outside experts say. The procedure sits in the verified layer — the edit counts, the ancient samples, the surrogates are consistently reported. The word "de-extinct" sits in the claim layer. Coverage that merged the two is where the confusion started.

The edit count and the evolutionary distance are on different scales

Twenty edits across 14 genes is a real technical achievement. It is also, set against a lineage that separated about 5.7 million years ago and was proposed for its own genus, a very small intervention. The mismatch is the objection in one line: the edits changed traits, not ancestry.

An unpublished company figure is a claim, not a result

Colossal's statement that dire wolves and gray wolves share about 99.5% of their DNA came from an analysis that had not been peer-reviewed when the pups were announced. High whole-genome similarity is unremarkable among canids, and it has to be read next to the Nature finding of deep divergence and no gene flow. Until the analysis clears review, it belongs in the claim column.

Two definitions of a species are competing, and both are stated openly

Beth Shapiro offers a functional test — looks like a dire wolf, acts like a dire wolf. Jacquelyn Gill offers a lineage-and-behavior test, noting that carrying more than 14 Neandertal genes does not make her a Neandertal. The IUCN's vocabulary sits between them: an animal that stands in for an extinct form phenotypically, behaviorally, or ecologically is a proxy, and the word facsimile is deliberately avoided.

The honest conservation case is the quiet one

The least disputed part of the program is not the dire wolf at all. Cloning four red wolves — the world's most endangered wolf, squeezed through a captive-breeding bottleneck — applies the same ancient-DNA, cloning, and multiplex-editing toolkit to a species that is still alive. Genetic rescue is a narrower promise than resurrection, and a far more defensible one.

Three separate downside risks, not one

The financial risk is opportunity cost, modelled in 2017 as a potential net biodiversity loss. The behavioral risk is moral hazard: if extinction reads as reversible, the urgency of prevention erodes — the exact framing the IUCN warns against. The ecological risk is that behavior and ecological fit cannot be edited in, which is why Kevin Daly's caution about releasing such animals is about the ecosystem, not the genome.

Comparison

What was announced, what was demonstrated, and how each should be read
StatementLayerWhat is actually establishedHow to read it
"The dire wolf is back"Company announcementThree living pups exist and were engineered from gray wolf cellsA claim about identity, not a demonstrated one — the framing is what is disputed
20 edits across 14 genes, about 15 dire-wolf-inspired variantsProcedure, consistently reportedThe edit count, ancient samples, and dog surrogates are not seriously disputedThe strongest factual ground in the story
Dire and gray wolves share about 99.5% of their DNACompany analysis, unpublishedNot peer-reviewed at the time of the announcementAwaiting scrutiny — read alongside the Nature divergence finding, not instead of it
Divergence about 5.7 million years ago, genus Aenocyon proposedPeer-reviewed, Nature 2021Deep separation from living wolves and coyotes, no evidence of interbreedingThe reference point the edit count has to be measured against
Four red wolves cloned for genetic rescueCompany announcement, expert-acknowledged applicationCloning reported by the company; genetic rescue is an accepted conservation strategyThe least contested part of the program — a living-species claim, testable over time
The vocabulary, and what each word commits you to
TermWho uses itWhat it meansApplied to these pups
De-extinctionCompanies, headlinesBringing an extinct species backThe contested framing — asserts identity with the extinct animal
ProxyIUCN Species Survival Commission (2016)A substitute representing an extinct form phenotypically, behaviorally, or ecologicallyThe institutional description: edited animals standing in for a function
FacsimileIUCN, as the term it avoidsAn exact copyExplicitly not what these are — and the company agrees identity is not the goal
Genetic rescueConservation biologistsReintroducing lost variation into a living population with low diversityThe red wolf work, and the most defensible use of the same toolkit

Process

  1. Who is making the statement

    A company press release and a peer-reviewed paper are different kinds of evidence, even when they describe the same animals.

  2. Is the procedure independently corroborated

    Here it is — the edit counts, the two ancient specimens, and the dog surrogates were reported consistently across outlets.

  3. Has the underlying analysis been published

    The genome analysis behind the 99.5% figure had not been peer-reviewed at announcement; the woolly mouse work was a preprint.

  4. Which definition of species is being used

    A functional test (looks and behaves like) and a lineage test (ancestry, behavior, ecology across generations) give opposite answers to the same question.

  5. Which word fits the result

    De-extinction asserts identity; proxy asserts substitution. The IUCN framework treats the second as the accurate description.

  6. Is there a measurable benefit to a living species

    Genetic rescue for the red wolf is testable over time; a benefit to charismatic extinct megafauna is not yet demonstrated.

Sources

  1. Nature (Perri et al.) — Dire wolves were the last of an ancient New World canid lineage (2021).View source (opens in a new tab)
  2. TIME — The Return of the Dire Wolf (2025-04-07).View source (opens in a new tab)
  3. Scientific American — The Dire Wolf Isn't Back, but Here's What De-Extinction Tech Can Actually Do (2025-04-08).View source (opens in a new tab)
  4. The Scientist — Dire Wolf De-Extinction Debate Divides Scientists (2025).View source (opens in a new tab)
  5. MIT Technology Review — De-extinction scientists say these gene-edited 'woolly mice' are a step towards woolly mammoths (2025-03-04).View source (opens in a new tab)
  6. IUCN SSC — Guiding Principles on Creating Proxies of Extinct Species for Conservation Benefit (2016).View source (opens in a new tab)
  7. Nature Ecology & Evolution (Bennett et al.) — Spending limited resources on de-extinction could lead to net biodiversity loss (2017).View source (opens in a new tab)
  8. Colossal Biosciences — Colossal Celebrates the First Birthday of Romulus & Remus (2025-10-01, company press release).View source (opens in a new tab)

Tags

  • #de-extinction
  • #colossal-biosciences
  • #dire-wolf
  • #gene-editing
  • #conservation