Trevor Snyder opens an incubator and lifts out a device that looks like a high‑tech coffee pod: black, with a honeycomb base and a clear flat top that reveals what’s inside. “This is a chicken embryo,” says Snyder, a bioengineer at Colossal Biosciences in Dallas, as he places the pod in a lighted stand. Through the top you can see a tiny heartbeat, a developing beak, eyes, feathers and the beginning of claws.
That 3D‑printed plastic shell is part of Colossal’s effort to build artificial eggs capable of supporting embryos from species that no longer exist. The company says it has successfully hatched healthy chicken chicks in the devices, a proof of concept that artificial eggs can perform the essential functions of a natural egg. So far, Colossal reports more than two dozen chicks have hatched in its prototypes.
Colossal’s larger goal is ambitious: to resurrect long‑extinct flightless birds such as the dodo and the giant moa. The dodo, which once lived on an Indian Ocean island, laid eggs only slightly larger than a chicken’s and those of its closest living relative, the Nicobar pigeon. The moa, by contrast, produced eggs the size of a football — far bigger than eggs laid by its present relatives like the emu. “There’s no bird on Earth today that could grow a moa embryo inside one of their eggs,” Snyder says. That gap is one reason the company is developing artificial eggs that can replicate the physical, chemical and gas‑exchange properties of natural eggs while scaling to much larger sizes.
Colossal plans to create embryos by editing cells from living relatives — for example, using Nicobar pigeon cells to build a dodo‑like embryo and possibly emu cells as a starting point for moa. Those genetically altered embryos would be placed in the engineered shells. The honeycomb structure in Colossal’s design, the company says, lets oxygen in while preventing leakage, and the shell is tuned to supply nutrients, remove waste and mimic the microenvironment an embryo needs to develop.
The achievement has drawn both excitement and skepticism. Some scientists see practical conservation benefits: the ability to incubate and rear endangered birds and reptiles that fail to survive in natural nests or in surrogate species. Andrew Pask, Colossal’s chief biology officer, called the artificial‑egg breakthrough “an incredible feat,” and paleobiologist Neil Gostling of the University of Southampton described the work as remarkable and almost science fiction in its ingenuity.
But others raise ecological and ethical concerns. Critics point out that reviving organisms or creating close facsimiles of extinct species does not restore lost habitats or guarantee long‑term survival; reintroduced animals could suffer if their historic ecosystems have been irreversibly altered or destroyed. Some researchers warn of unpredictable ecological consequences if long‑absent species are reintroduced.
Nic Rawlence, an ancient ecology researcher at the University of Otago, questions whether these efforts amount to true de‑extinction. He argues Colossal is engineering modern species to resemble extinct ones — producing approximations rather than genuine restorations of lost species. “They’re not what I would call de‑extinct species,” he says. “Extinction is still forever.”
Colossal defends its approach. The company has publicly signaled broader ambitions — including plans for artificial wombs to gestate mammals such as the woolly mammoth — and frames its work as a way to reverse human‑caused extinctions. Co‑founder Ben Lamm has said the company views these projects as rectifying past harms.
The artificial‑egg milestone is an important technical step: it shows a synthetic shell can support embryo development to hatching in at least one species. Whether that technical capability should be applied to resurrecting extinct species, and under what ecological, ethical and regulatory constraints, remains a subject of active debate among scientists, conservationists and ethicists. For now, Colossal is scaling its designs to larger eggs and pursuing the next stages of its de‑extinction and conservation programs, even as questions about feasibility, identity and impact persist.
