Here's One Big Reason Why Scientists Want To Bring Back Woolly Mammoths

Few extinct animals other than the dinosaurs have attracted more attention than the woolly mammoth (Mammuthus primigenius). Between 700,000 and 4,000 years ago, at the peak of the last ice age, these furry behemoths were widespread across the Arctic reaches of North America, Europe, and Asia. They lived at the same time as humans, and while the exact cause of the woolly mammoth's extinction is not firmly known, it is widely believed that human hunters, in tandem with climate change as the ice age came to a close, brought about their end. Since then, many have speculated about what the world would be like if woolly mammoths never went extinct, but now one company is trying to answer that question for real.

Colossal Biosciences, an American biotech laboratory, has been making headlines for its ambitious plans to "de-extinct" the woolly mammoth and several other long-lost species. According to the company's website, their top goal in this pursuit is to "increase resilience of habitats to climate change and environmental upheaval." It's a hopeful goal that arises from a tragic reality. Anthropogenic climate change is devastating the world, and has already caused more extinctions than we can know. Since humanity has made no meaningful changes to curb this destruction, perhaps wildlife can be altered to tolerate it. Colossal aims to use their mammoth project as a study in how animals adapt to specific environmental conditions, and how genome editing might be able to accelerate those adaptations. But getting there is going to be complicated.

Colossal Biosciences bills their woolly mammoth project as a feat of "de-extinction," but that's not exactly the truth. It's impossible to bring back an extinct species because there is no way to obtain its complete genome. Colossal made headlines in the spring of 2025 when they claimed to have undone the extinction of the dire wolf, presenting three young wolves with white fur and strong musculature, but they aren't actually genetically identical to dire wolves. They were created by editing the DNA of gray wolves. There is a scientific consensus that these are not dire wolves, but simply slightly mutated gray wolves, and even Colossal itself has echoed this stance.

"De-extinction" is based on the same technology used to clone animals, which begins with isolating just a single cell from a donor animal. Scientists then extract the nucleus of that cell and inject it into an egg cell, which becomes a full embryo and gets implanted in a surrogate mother until birth. This produces an exact genetic replica of the donor animal, but the team at Colossal is taking it one step further. They splice into the genome of the donor nucleus and edit individual genes within it to match DNA samples taken from specimens of extinct species. The process for reviving woolly mammoths would be similar to the process of reviving dire wolves, except that the gray wolf would be replaced by the Asian elephant, which is the woolly mammoth's closest living relative.

Colossal's quest to create woolly mammoths, or rather, woolly elephants, has already begun to bear fruit. In March of 2025, the company unveiled a woolly mouse, with shaggy fur and fat-storing abilities ideal for surviving in cold climates. Scaling up from mouse to mammoth won't be easy, but it's definitely possible given what Colossal has already produced. However, when and if they succeed in their mammoth endeavor, they might discover some unintended, and very dangerous consequences.

Efforts to "de-extinct" species have raised significant ethical concerns due to the potential harm that can be done to donor animals, surrogate mothers, and their genetically modified offspring. Cloned animals frequently suffer from health issues and premature death. The first ever attempt at reviving an extinct species was made in the early 2000s in effort to restore the recently extinct Pyrenean ibex. Seven surrogate goat mothers became pregnant with genetically edited embryos, but six miscarried, and the only baby successfully born had a severely deformed lung that killed it within minutes.

Surrogate mothers are also at risk of repeated miscarriages and internal trauma from being forced to bear offspring their bodies aren't designed for. This is an especially great concern in the case of the woolly mammoth, because mammoths were larger than the Asian elephants that Colossal plans to use as surrogates. If the mammoth offspring grow larger than the Asian elephant's womb can safely accommodate, the consequences could very well be death for both mother and child.