Colossal Biosciences announced Tuesday that it hatched 26 live baby chickens from a 3D-printed structure designed to mimic an eggshell, a step the company says could eventually lead to reviving New Zealand's extinct giant moa, a bird that stood 12 feet tall. Independent scientists, however, say the technology is far more modest than the company's grandest ambitions suggest.
The chicks, ranging from a few days to several months old, were produced by pouring fertilized egg contents into the artificial system, adding calcium, and incubating them while scientists monitored embryo development in real time, CBS News reported. Colossal released images and video showing researchers carefully handling the hatchlings.
It's a genuine engineering feat. But the gap between hatching a chicken in a lab and resurrecting a species that vanished centuries ago is enormous, and the outside experts quoted on the record make that plain.
The system uses a titanium 3D-printed shell paired with a bio-engineered silicone membrane designed to replicate the oxygen transfer that occurs through a natural eggshell, the New York Post reported. That membrane addresses a problem that plagued earlier shell-less bird embryo experiments, in which chicks often failed to develop fully.
Colossal CEO Ben Lamm framed the advance in ambitious terms:
"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 also said the company did not want to wait until it was ready to produce a giant moa before tackling the hardest engineering problems.
"We didn't want to wait till we were ready to birth a giant moa. We actually wanted to start working on the engineering challenges for surrogacy and birth now."
On social media, Colossal posted that the platform "could help rescue fragile bird embryos, hatch birds that refuse to breed in captivity, and potentially revive species preserved as frozen cells and DNA." The company says it envisions adapting the technology to larger eggs, moa eggs are roughly 80 times the size of a chicken's, and applying it to conservation of endangered species with poor hatch rates.
The distinction between an "artificial egg" and an "artificial eggshell" may sound like semantics. It isn't. The fertilized egg contents, the yolk, albumen, and all the biological machinery needed to grow a chick, still came from a real hen's egg. Colossal replaced only the shell and the membrane.
Vincent Lynch, an evolutionary biologist at the University at Buffalo, was blunt, as the Associated Press reported:
"That's not an artificial egg because you've poured in all the other parts that make it an egg. It's an artificial eggshell."
Lynch went further on the de-extinction question. He said the technology might help produce a genetically modified bird, but that result would not actually be a moa.
"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."
Nicola Hemmings, who studies bird reproductive biology at the University of Sheffield and is not part of the Colossal team, offered similar caution. She noted that producing a chick from an artificial vessel "is not necessarily new", researchers in decades past used cruder technology, including plastic films and sacks, to hatch chicks outside natural shells.
Hemmings said her own priorities lie elsewhere:
"My personal interests lie more in preserving what we've got than trying to bring back what is already gone."
That is a polite way of saying that billions of dollars and years of scientific talent might do more good protecting species still alive than chasing the resurrection of ones that aren't.
Colossal has built its brand on audacious promises. The company made a splash in 2021 when it unveiled a plan to revive the woolly mammoth. It later added the dodo bird to its roster. In 2024, Colossal said it achieved a breakthrough in efforts to bring back the extinct Tasmanian tiger. The company has previously announced that it genetically engineered living animals to resemble extinct species.
In a 2023 interview, CBS News correspondent Jonathan Vigliotti told Lamm directly that the whole enterprise sounded like science fiction. Lamm's response was characteristically confident:
"Yeah, I mean, it is, until it's not."
That kind of confidence sells well to investors and generates headlines. But each of Colossal's milestones has come with a similar pattern: a dramatic announcement, sweeping language about what the technology "could" do, and then a quieter acknowledgment from outside researchers that the actual advance, while real, is far more limited than the press release implies.
Dr. Beth Shapiro, Colossal's own chief science officer, told the New York Post that "the artificial egg changes that", referring to the challenge of incubating birds like the dodo and moa, which cannot rely on modern surrogate birds because no living species lays eggs large enough. That is a legitimate technical obstacle. But solving the incubation problem is only one piece of a puzzle that also requires reconstructing an extinct genome, engineering viable embryos from that genome, and, perhaps most daunting of all, finding a place for the animal to live.
Arthur Caplan, a bioethicist at New York University's Grossman School of Medicine, raised the question that rarely appears in the breathless coverage of de-extinction breakthroughs:
"The big challenge is, what environment is this animal going to live in?"
The South Island giant moa roamed New Zealand's forests before human settlement drove it to extinction. Those forests are not what they were. The ecosystems that sustained a 12-foot flightless bird no longer exist in their original form. Creating a genetic facsimile of the moa, even if the science eventually gets there, does not recreate the world the moa lived in.
Colossal says bird species are in sharp decline, and that its platform could help. That much is true: conservation applications for endangered birds with fragile embryos or poor captive breeding rates are a more grounded use case than mammoth or moa revival. If the artificial eggshell system can be refined and scaled for species that are still with us, it could be genuinely useful.
But the headline-grabbing claims about extinct species serve a different purpose. They attract funding, media attention, and public fascination. Whether they attract honest scientific scrutiny in equal measure is another matter.
None of this means Colossal's work is without value. Hatching 26 healthy chicks from a reusable, 3D-printed incubation system is a real accomplishment. The titanium shell and bio-engineered membrane represent genuine engineering. And the ability to image embryo development in real time inside the artificial structure could yield useful data for avian biology.
The problem is the distance between what the company demonstrated and what it advertises. Twenty-six chickens hatched from an artificial eggshell is not the same as reviving a 12-foot bird that has been extinct for centuries. Independent scientists said as much on the record. The company's own statements acknowledge the gap, even as its marketing materials gloss over it.
Colossal has not published a peer-reviewed paper tied to this announcement, at least not one referenced in any of the available reporting. That does not mean the results are fabricated. It does mean the scientific community has not yet had a chance to evaluate the claims on its own terms.
For now, the chicks are real. The moa is not. And the distance between those two facts is measured in decades of unsolved science, if it can be solved at all.
Taxpayers and donors who fund ambitious science deserve straight talk about what a breakthrough actually is, not a press release dressed up as a resurrection.
