A bird that disappeared 300 years ago may be making a comeback

At least that is what the American biotechnology company Colossal Biosciences, which works in the field of "de-evolution" of species, is aiming for.

Colossal has announced that it has grown primordial germ cells - the precursors of eggs and sperm - from the blue pigeon, one of the dodo's closest relatives. This was a major milestone in the complex process of recovering the extinct bird.

The next step will be to edit the same cells in the Nicobar pigeon, the closest living species to the dodo. Scientists have already established a population of these birds in Texas and are developing methods to culture their cells.

"The ability to keep pigeon cells viable for long periods of time is a real breakthrough in the dodo revival project," said Colossal co-founder Ben Lamm.

Unlike in mammals, in birds the cloning process is much more complicated. In mammals it is possible to replace the nucleus of the egg with the nucleus of the donor, but in birds the eggs are large, opaque and laid after the beginning of embryo development.

Previously, scientists have been able to cultivate and edit such cells in chickens and geese. In one experiment, a duck became the "father" of a chicken, but this method did not work even with closely related species - for example, quail.

In the case of the dodo, the team tried more than 300 different "recipes" before they were able to keep the blue pigeon's cells alive for 60 days. The results have been published on the scientific preprint server bioRxiv.

According to the plan, the edited Nicobar pigeon cells will be introduced into chicken embryos. Such hens will grow up with "pigeon" sex cells and will be able to lay eggs, from which will hatch already genetically modified pigeons, and in the future - birds as close as possible to drones.

Colossal plans to reintroduce the revived dodo to the island of Mauritius, where the species lived before its extinction in the 17th century.

The news comes two months after the company announced the launch of a similar project to reintroduce the giant moa, a flightless bird that disappeared in New Zealand some 600 years ago.

Colossal's chief scientific adviser, Beth Shapiro, said the technologies being developed as part of the "resurrection" of the dodo offer new perspectives on the conservation of rare birds.

An example is the pink Mauritian dove, which is threatened with extinction in the next 50 to 100 years due to inbreeding.

The company is also working on recreating the mammoth, the Tasmanian wolf and even pseudodirewolves similar to those that became popular after the TV series Game of Thrones.

Nevertheless, critics stress that without a complete genome, we can only talk about creating genetic analogues, but not exact copies of extinct species.