For the first time since it went extinct more than 300 years ago, the return of the dodo has edged closer to reality after scientists declared a breakthrough that could see the bird roam Mauritius once again.
Colossal Biosciences, a biotech firm in Texas, US, said it had successfully cultured pigeon primordial germ cells – the precursors of sperm and eggs – in a laboratory setting through a technique it described as a “pivotal step” towards reviving the dodo.
Colossal chief executive Ben Lamm said the company expected to reach its goal of creating a live dodo in 5-7 years. “But it’s not 20 years out,” he told The Guardian.
The company, which attracted high-profile backers and headlines after announcing the birth of three dire wolf pups in April, is using the Nicobar pigeon, the dodo’s closest living relative, as the genetic base.
Colossal, which plans to also recreate the woolly mammoth, announced it had raised $120m in additional funding for its work, making a total of $555m since launching in 2021.
To bring back the dodo, the firm’s plan is to edit the pigeon primordial germ cells with dodo DNA before implanting them into surrogate chicken that have been modified to carry them.
The technique to bring the dodo back is more challenging than what the company did to recreate a version of the dire wolf considering birds develop inside an egg and can’t be cloned in the same way as mammals.
“So with birds, the slowest part of this process is that we have to make two generations,” Beth Shapiro, chief science officer at Colossal said, according to CNN.
“We can’t clone the cells, so we have to make moms and the dads separately and then breed them in order to get both copies of the gene to be modified. That is pretty slow.”
The company said it planned to make enough dodos with genetic diversity that they could be left out in the wild and thrive.
“So we’re not looking to make two dodos, we’re looking to make thousands,” Mr Lamn said.
According to Colossal, the advance is a “really important step for the dodo project but also for bird conservation”.
But scientists caution that Colossal’s announcement does not mean the true dodo can be brought back.
“It’s hard to know what it took to make a dodo genetically, from its genomic architecture to how its genes interacted with the environment,” Leonardo Campagna, an evolutionary biologist at the Cornell Lab of Ornithology, told The Guardian.
“I’d be curious to see a pigeon like that. But is this in fact the dodo? We need to acknowledge that there is a lot we don’t know and maybe never will.”
Others question whether such projects divert attention from protecting species currently at risk.
“By labelling genetically engineered modern species as extinct ones brought back from the dead … it’s a huge moral hazard; a massive enabler for the activities that cause species to go extinct in the first place,” Rich Grenyer, a biologist at the University of Oxford, told The Guardian.
Colossal insisted that its research could also help endangered birds, for example by editing disease-resistant traits into struggling populations.
Colossal also said its de-extinction projects could inspire the public about science.
But critics point out that conservation, not re-creation, remains the urgent task. “Technology can’t solve the biodiversity crisis,” Prof van Oosterhout told CNN. “It might save a few species, but it’s not a magic bullet.”
The last confirmed sighting of the dodo was in 1662, when European sailors recorded the large, flightless bird in Mauritius.
Hunted heavily by humans and targeted by invasive species like rats and pigs, the dodo vanished from the world and became a global symbol of extinction.