Colossal Biosciences Advances Artificial Egg Technology in Bid to Resurrect Extinct Birds

In a groundbreaking development that blurs the lines between science fiction and reality, baby chicks have been observed shifting and attempting to hatch, not from traditional eggshells, but from transparent, 3D-printed plastic cups at the Dallas headquarters of Colossal Biosciences. The biotech company announced what it describes as a “fully artificial egg,” though “artificial eggshell” might be a more accurate term. This innovative structure is an oval-shaped, printed lattice lined with a special silicone-based membrane designed to facilitate oxygen exchange, mimicking a natural eggshell. Researchers achieved this feat by carefully transferring the contents of recently laid chicken eggs into these artificial containers, where the embryos continued their development. Andrew Pask, Colossal’s chief biology officer, expressed profound excitement, stating, “To see them all moving around in their artificial eggs was absolutely mind blowing. You really feel you can grow life outside of the womb.” Founded in 2021 with an ambitious vision to restore extinct species like the woolly mammoth through gene editing and reproductive technology, Colossal Biosciences has since secured over $800 million in funding. The company views this artificial egg technology as a crucial step towards the “scalable and controllable” creation of animals, with potential applications extending to the conservation of at-risk bird species and, ultimately, the resurrection of the giant moa, a colossal flightless bird that once roamed New Zealand and laid four-liter eggs. While the prospect of resurrecting the moa, which went extinct approximately 750 years ago due to human hunting, is tantalizing, Colossal acknowledges the immense challenges. Re-creating the moa would necessitate analyzing ancient moa DNA and introducing thousands of genetic modifications into the genome of an existing bird species. This remains a technically formidable task, regardless of the artificial egg technology. Furthermore, the company’s claims have drawn scrutiny from the scientific community. Some experts, like Katsuya Obara from the University of Tsukuba, argue that Colossal is overstating its achievements, noting that growing birds in artificial containers dates back to 1998 with quail, and chickens were hatched under transparent film as recently as 2024. Critics contend that Colossal’s “first-ever shell-less incubation system” is essentially a modification of existing methods, accusing the company of making exaggerated claims, reminiscent of past controversies such as their disputed assertion of re-creating the dire wolf. However, Colossal’s potential advance lies in its specialized membrane, which allows embryos greater access to oxygen, potentially improving hatch rates compared to previous systems that required supplemental gas and often resulted in failed hatches. This work is spearheaded by Colossal’s exogenous development (Exo Dev) team, which is also exploring artificial wombs for mammals, starting with marsupials, considering the chicken’s natural ex utero development as a simpler starting point. Creating a moa embryo would require genetically altering avian stem cells to produce moa-like sperm or eggs, a process currently only feasible with chickens. This could lead to the unusual scenario of a chicken laying an egg containing a moa embryo. However, significant hurdles remain, particularly concerning the vast size disparity between a chicken egg’s yolk and the nutritional demands of a much larger moa chick. Professor Helen Sang of the Roslin Institute highlights these evolutionary differences, questioning whether a moa embryo could survive on a chicken yolk. Despite these challenges, Pask remains optimistic, suggesting that the artificial egg could facilitate the necessary nutritional support. He envisions using a fine needle to combine multiple chicken yolks, potentially “put 50 yolks together to make that yolk mass much larger,” thereby addressing the size and nutrient requirements for a successful moa development to term. This ambitious vision underscores Colossal Biosciences’ commitment to pushing the boundaries of biotechnology in its quest to bring extinct species back to life.