A biotechnology company focused on reviving extinct species has announced the successful hatching of live chicks within an artificial environment, sparking mixed reactions from scientists and critics of its ambitious de-extinction mission.
Breakthrough in artificial eggshell technology
Colossal Biosciences says 26 baby chickens, ranging from just days to several months old, were born from a 3D-printed lattice structure designed to mimic an eggshell. The company had previously genetically engineered living animals to resemble extinct species, including mice with woolly mammoth-like traits and wolf pups resembling dire wolves.
Ben Lamm, CEO of Colossal, suggested this artificial eggshell technology could eventually be scaled up to genetically modify living birds to resemble New Zealand's extinct South Island giant moa. Moa eggs are about 80 times larger than a chicken's and would be difficult for any modern bird to lay. "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," Mr Lamm said.
Scientific skepticism
Independent scientists acknowledge the technology's impressiveness but argue it lacks crucial components to be considered a truly artificial egg. They also contend that reviving extinct creatures is likely unachievable. "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," stated Vincent Lynch, an evolutionary biologist at the University at Buffalo.
To hatch the chicks, Colossal scientists poured fertilised eggs into their artificial system and placed them in an incubator. They supplemented calcium, typically absorbed from the eggshell, and monitored embryo development in real-time. The artificial eggshell features a membrane that regulates oxygen intake, much like a natural egg. However, other vital egg components—such as temporary organs that nourish and stabilise the growing chick and remove waste—were not included. "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," Mr Lynch added.
Historical context and future challenges
In past decades, researchers have used more rudimentary technology to create transparent eggshells, successfully hatching chicks from plastic films or sacks. Such innovations are valuable for studying chicken development and gaining insights applicable to other mammals and even humans. "Producing a chick from an artificial vessel is not necessarily new," commented Nicola Hemmings, a bird reproductive biology specialist at the University of Sheffield, not affiliated with Colossal.
A considerable journey lies ahead before Colossal can attempt a moa resurrection using this artificial egg system. Scientists must first compare ancient DNA from well-preserved moa bones with genomes of living bird species, and a significantly larger eggshell would be required. "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," Mr Lamm explained.
Even if Colossal succeeds in creating a large bird resembling the moa, some scientists express concern about its post-birth survival, particularly in a landscape that bears no resemblance to its ancient habitat. "The big challenge is, what environment is this animal going to live in?" questioned bioethicist Arthur Caplan from New York University's Grossman School of Medicine.
Such de-extinction efforts might hold more promise for currently endangered species, where scientists could preserve sperm and egg cells from living members to bolster populations, Ms Hemmings suggested. "My personal interests lie more in preserving what we've got than trying to bring back what is already gone," she concluded.
