Twenty-six baby chickens hatched inside a 3D-printed lattice structure that mimics the architecture of an eggshell—not from the biological marvel nature designed, but from something humans engineered in a lab. Colossal Biosciences, a biotech company on a mission to resurrect extinct species, announced this week that the artificial environment successfully brought living chicks into the world, marking a significant engineering milestone, though one that sparked both scientific intrigue and healthy skepticism about the company's grander ambitions.
The significance lies not in resurrecting chickens—we have plenty of those—but in what Colossal is ultimately chasing: the ability to hatch creatures far larger and more exotic than a bird we eat for dinner. The company has already genetically engineered mice with the long hair of woolly mammoths and wolf pups designed to resemble dire wolves. Now, CEO Ben Lamm envisions a future where this artificial incubation technology scales up to hatch the South Island giant moa, an extinct New Zealand bird whose eggs were 80 times larger than a chicken's egg—far too massive for any living bird to produce naturally. "We wanted to build something that nature has done a pretty good job of developing and make it better and scalable and even more efficient," Lamm explained.
To create the artificial environment, Colossal scientists poured fertilized chicken eggs into the 3D-printed system and placed them in an incubator. They supplemented calcium that would normally be absorbed from a real eggshell and monitored embryonic development in real-time through imaging. The artificial eggshell features a carefully engineered membrane designed to allow the precise amount of oxygen to pass through, mimicking the gas exchange that occurs in nature.
Yet independent scientists were quick to inject nuance into the celebration. Vincent Lynch, an evolutionary biologist at the University at Buffalo, points out that Colossal has created an artificial eggshell—not a true artificial egg. Real eggs contain temporary organs that form during development to nourish the growing chick, provide structural support, and manage waste. The Colossal system sidestepped these biological complexities by essentially pouring all the missing components directly in. "They might be able to use this technology to help them make a genetically modified bird, but that's just a genetically modified bird. It's not a moa," Lynch said.
This skepticism extends beyond semantics. Nicola Hemmings, a bird reproductive biologist at the University of Sheffield, notes that hatching chicks from artificial vessels isn't new—researchers have successfully done it with plastic films and sacks for decades. That work has genuine value for understanding development in birds and other mammals, including humans.
The road to an actual moa is far longer than the incubation period of a chicken. Scientists would need to sequence ancient DNA from well-preserved moa bones and compare it to modern bird genomes. They'd need a much larger artificial eggshell. And even if they succeeded in creating a tall bird resembling the extinct moa, bioethicist Arthur Caplan of New York University's Grossman School of Medicine raises a more sobering question: "What environment is this animal going to live in?" The landscape of New Zealand has transformed dramatically since the moa disappeared.
Some scientists argue that de-extinction efforts might make more sense applied to currently endangered species, where preserved genetic material from living members could restore populations at risk of vanishing right now. "My personal interests lie more in preserving what we've got than trying to bring back what is already gone," Hemmings said. For now, Colossal's 26 chicks represent an engineering proof of concept—impressive, but far from the resurrection story the company is ultimately seeking.