After Rhinos and Wolves, Scientists Wants To Create Artificial Wombs

When you look at it, the last two northern white rhinos on Earth spend their days as if they were not the last two northern white rhinos on Earth. They lumber majestically along a dun and dusty landscape, as their ancestors have done for millions of years.

They graze with dedication on tremendous amounts of grass — more than 100 pounds a day — uprooting the plant with the flat, powerful lips that evolution painstakingly bestowed. They wallow in the mud, or rest in the shade of acacia trees, or gaze, placidly, in the direction of Mount Kenya. Sometimes, they let egrets rest on their hulking, primordial backs.

Then again, as the last two northern white rhinos on Earth, Najin and Fatu have lives that are singular. Armed rangers at the Ol Pejeta Conservancy guard them from poachers every minute of every day. Buses of tourists and schoolchildren gather at the conservancy’s electric fence, angling for a glimpse of the tail ends of an evolutionary line that’s been stretching back to the time horses were the size of dogs and the continent of Australia had not yet broken free of Antarctica.

Normally, northern white rhino females would live with their young in small herds, but Najin and Fatu have only each other. The last male northern white rhino, Sudan, died in 2018. Najin and Fatu, his daughter and granddaughter, have health issues that make it impossible for them to reproduce; and so in a term both clinical and heartbreaking, the species is already considered "functionally extinct," its remaining two members living in an evolutionary twilight.

Some animals are so endangered and elusive that we don’t even know if they still exist; many extinctions happen without human awareness or acknowledgment. But we will know the exact minute when northern white rhinos go extinct. We will be able to mark the day dolefully on a calendar.

And yet. For the past 50 years, and in anticipation of their demise, scientists have been banking tissue samples of the species in repositories like San Diego’s Frozen Zoo.

For some time now, they have been retrieving eggs from Najin and Fatu and fertilizing them with sperm collected from northern white rhinos that have already perished. Thirty-nine viable embryos have been created via IVF. In 2023, scientists and veterinarians achieved the first successful IVF pregnancy in a rhino species, using both an embryo and surrogate from the relatively more plentiful southern white as proof that the technique could work. The fetus was only 70 days old when the mother died of a bacterial infection. Since then, three northern white rhino embryos have been transplanted into southern white rhinos, but none of these interspecies transfers has been successful.

In February, scientists from Colossal Biosciences reported that they were nearing a breakthrough. Colossal is a for-profit company that was co-founded in 2021 by billionaire and serial entrepreneur Ben Lamm and Harvard geneticist George Church with the mission of using recent scientific developments — in gene editing, in collecting and analyzing ancient DNA, in cellular biology, and in embryology, among others — to "de-extinct" lost animals.

In early 2025, the company reported the creation of 38 "woolly mice," in which gene edits had been made to replicate the long, thick fur and cold-resistant metabolism of woolly mammoths. (Though technically just a quality-control step to see how the genes would be expressed in an animal whose DNA is well understood, the mice turned out to be so freakishly adorable that people showed up at the lab trying to get their hands on one, and Colossal had to beef up its security.)

Then, in April 2025, the company announced with much fanfare that it had extracted DNA from a 72,000-year-old skull and a 13,000-year-old tooth, used computational biology to figure out which genes did what within that DNA, made 20 edits to the cells of gray wolves that would cause them to express certain phenotypes, or physical traits, created embryos from those edited cells, and then de-extincted the dire wolf.

"We are pleased to announce that, for the first time ever in history, we have successfully resurrected a prehistoric pop-culture icon," proclaimed a promotional video by Krampus director Michael Dougherty.

Artificial wombs have been on Colossal’s agenda since the company’s very earliest days, back when Lamm called up Church with a question about algae. Church is widely recognized as the father of synthetic biology and was one of the first scientists to edit the human genome with CRISPR, a technology that works like "molecular scissors" to cut DNA at precise points.

He is also a TED Talk darling with a knack for supporting scientifically plausible ideas that sound like science fiction; he has discussed editing genes to make them do such things as age in reverse, encode and store digital information like books, and be resistant to the damage caused by radiation they would be exposed to in interplanetary travel. He has applied for 170 patents. He sees himself as an intellectual provocateur.

"I think that’s probably my main role, not just in Colossal but in everything I do," Church said. "I don’t try to change opinion about things, but I do try to help people see what is possible, and listen very carefully to what society wants and doesn’t want, as it is a moving target. Almost everything that’s really cool in technology at one point somebody hated, and usually the haters are particularly loud about it."