Few extinct creatures have captured the public imagination as much as the woolly mammoth (Mammuthus primigenius). During the Last Glacial Maximum, 700,000–4,000 years ago, these massive, fur‑covered proboscideans roamed the Arctic reaches of North America, Europe, and Asia, coexisting with early humans. While the exact cause of their extinction remains debated, most experts point to a combination of overhunting and rapid climate warming. Scientists have long wondered how ecosystems might differ if mammoths had survived—and a biotech company is now turning that speculation into a concrete research agenda.
Colossal Biosciences, a U.S. biotechnology firm, has garnered attention for its ambitious “de‑extinction” initiatives, targeting the woolly mammoth among other long‑lost species. The company states its overarching goal is to “enhance ecosystem resilience in the face of climate change and environmental disturbances.” With biodiversity loss accelerating under human influence, the firm argues that genome editing could help future wildlife better tolerate shifting conditions.
Colossal markets its mammoth program as a true de‑extinction effort, but the scientific reality is more nuanced. A complete, intact genome of a woolly mammoth has never been recovered; what can be achieved is a genetic surrogate that combines a living relative’s genome with edited segments derived from ancient DNA. In spring 2025, Colossal announced the creation of “dire wolf‑like” gray wolves, noting that these animals are not true dire wolves but are engineered gray wolves with selected traits.
The methodology builds on somatic cell nuclear transfer (SCNT), a cloning technique that transfers the nucleus of a donor cell into an enucleated egg. The embryo is then implanted into a surrogate. Colossal takes this a step further by inserting edits into the donor genome to match DNA fragments from extinct species. For the mammoth, the donor would be an Asian elephant, the closest extant relative of the woolly mammoth.
While Colossal has already produced a “woolly mouse” in March 2025—an engineered mouse with shaggy fur and enhanced fat storage—scaling this approach to a mammoth presents significant hurdles. Moreover, the project raises ethical questions about the welfare of donor animals, surrogates, and the engineered offspring. Cloned animals often suffer from health complications and shortened lifespans. The first attempt at reviving an extinct species, the Pyrenean ibex in the early 2000s, ended in failure after six pregnancies and one malformed newborn that died shortly after birth.
Surrogate mothers can experience repeated miscarriages and internal injuries when carrying embryos that exceed their natural reproductive limits. This concern is especially acute for mammoth reproduction, as the planned offspring would likely grow larger than the Asian elephant’s gestational capacity, potentially endangering both mother and child.
