So Lamm stepped down from Hypergiant and joined forces with the six-foot-five “king of synthetic biology.” The pair set out to bring back the woolly mammoth, in addition to other extinct species, like the moa bird and the dire wolf. They were motivated by a grim statistic: One third of the world’s animal and plant species are projected to go extinct by 2050.
Andrew Pask, Colossal’s chief biology officer, said that we missed the chance to “hit the stop button” on planet-wreckers like global warming. “We actually have to reengineer things that we’ve already lost because we’ve already gone too far,” he said.
Last year the company claimed it bred three dire wolves, the six-foot-long wolf that went extinct roughly 10,000 years ago. Critics pushed back: New Scientist called the pups “gene-edited grey wolves that look a bit like dire wolves.” Still, Colossal hailed the wolves, which were born via hound surrogate, as a success.
But Pask said using surrogates is difficult when trying to repopulate whole species. For example, if Colossal were working to restore a koala population after a bushfire with 100 new koalas, “right now we’d need 100 koala surrogates.”
“It’s just not feasible to do that, particularly if they’ve just had a massive population decline,” he said.
The egg is the company’s first big win in artificial-gestation technology. Although synthetic eggs existed before, Pask said they were “unsophisticated” and required scientists to manually pump oxygen to the embryo. Colossal’s egg is a hexagonal, 3D-printed frame covered in clear nanomaterial that allows oxygen to flow in but prevents moisture from flowing out.
Crucially, Colossal’s egg includes a small window at the top to let the researchers “actually see the embryo as it’s developing,” Pask said. When the chicks are ready to hatch, they poke through the membrane, just like with a real egg.
So far the eggs have successfully incubated 26 chicks, which are living on Colossal’s Dallas ranch. The team will spend the next six months ensuring the chickens are healthy and can reproduce, before potentially using the eggs to birth dodos.
Lamm said the team has already learned an “enormous” amount that it will carry into its artificial-womb development, like how to deliver nutrients to an embryo throughout the growth process and “how sensitive embryos are to even very small changes in those systems.”
Down the road will be marsupials, then larger mammals like elephants—provided the company can successfully build its artificial wombs. It will be a long and potentially fruitless road. Pranam Chatterjee, a bioengineering professor at the University of Pennsylvania who worked in Church’s lab and contributed to some of Colossal’s early work, estimated that we’re decades away from a human artificial womb.
He said scientists still need to understand how to engineer tissues necessary for a healthy birth, from the placenta to the uterine lining. Even beyond that, Chatterjee emphasized, there is a lot we don’t yet know about the reproductive process.
Our current knowledge is like a film with a low frame rate: Chatterjee said we have snapshots, such as measurements of hormone levels, but we don’t have the full story, like how the womb induced those hormones at that time. “Those steps are still being studied, and we’ll get there,” he said. “But we’re not there yet.”
