Scientists at Colossal Biosciences, a Texas-based de-extinction company, have announced the successful hatching of chicks from an artificial egg, a development that could represent a major innovation if verified. The company claims its artificial egg supports the full development of bird embryos outside a biological eggshell without supplemental oxygen, as part of its broader plan to 'de-extinct' birds such as the giant moa and dodo.
What Is the Artificial Egg Technology?
Artificial egg technology, which involves transferring and growing a developing chick embryo outside a natural eggshell, has existed since the 1980s. Live birds have been hatched and raised to adulthood using such systems. The technology is currently used for research into embryo development, tumour growth, and the creation of genetically modified chickens, as well as for drug and vaccine development.
However, widespread use has been hindered by the need to supply pure oxygen directly to the embryo, which can affect chick viability. Colossal claims to have solved this by replacing the hard eggshell and membrane with an open, latticed half-shell and a transparent silicone-based membrane that allows oxygen to diffuse freely from the air into the embryo.
How Does It Work?
The company plans to transfer a fertilised embryo and yolk from a real egg into the artificial egg, which would then be housed in incubators. Embryo development would be observed directly through the transparent membrane. Colossal aims to genetically modify an emu genome to resemble that of a moa, create an embryo inside an emu egg, and bring it to term using the artificial egg. Similarly, they intend to genetically engineer a Nicobar pigeon to look more like a dodo.
Challenges and Limitations
Key to the technology is its scalability in size, but it still requires a fertilised embryo and yolk. Given the size differences between chicken eggs and emu eggs (up to 12 times larger) and giant moa eggs (up to 80 times larger), there is insufficient yolk and egg white in any living bird's egg to support a giant moa chick. An egg yolk is a single cell, and simply injecting extra yolk is not feasible. Bird embryo development is complex and species-specific, and it remains to be seen whether the artificial egg can produce healthy individuals.
Moreover, there is widespread Māori and public opposition in New Zealand to Colossal's plans to 'de-extinct' the moa for an ecotourism venture.
Potential Conservation Applications
Colossal claims the technology has broad applications for conservation, particularly for captive breeding of critically endangered species like the kākāpō, kakī black stilt, and pukunui southern dotteral. Eggs damaged by inexperienced parents or adverse weather could be rescued into artificial eggs to help chicks survive. Combined with genome engineering, artificial eggs could reintroduce lost genetic diversity or make birds resistant to diseases, and potentially reverse the impacts of inbreeding on low hatching success.
However, for critically endangered birds with few natural eggs, transgenic birds would be needed to produce enough chicks. For example, chickens could provide sperm and egg cells containing genetically modified DNA from a different species. After mating, the fertilised embryo and yolk could be transferred to the artificial egg.
Ethical and Practical Considerations
Ethical questions remain about whether such steps should be taken, even if technologically possible. The use of artificial egg technology in conservation, especially with genome engineering and transgenic birds, would require transparent engagement with Indigenous communities as guardians of endangered species. It is also vital that this technology is not privatised; if it is to make a meaningful difference, it must be available to public-sector conservation organisations.
If the technology lives up to the hype, it will not be a silver bullet for species declines. In the short term, saving species from extinction will still depend on predator control and habitat restoration.
About the author: Nic Rawlence is an Associate Professor in Ancient DNA at the University of Otago. This article is republished from The Conversation under a Creative Commons license. Read the original article.
