The dodo was the poster child of man-made extinction. Scientists want to bring it back.

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No other animal is as inexorably linked to extinction as the dodo, a strange flightless bird that lived on Mauritius in the Indian Ocean until the end of the 17th century.

The arrival of sailors brought with them invasive species like rats and practices like hunting. They condemned the dodo, which did not fear man, to disappear in just a few decades.

Now, a team of scientists wants to bring back the dodo in a bold move that will incorporate advances in ancient DNA sequencing, gene-editing technology and synthetic biology. They hope the project will open up new techniques for bird conservation.

“We are clearly in the midst of an extinction crisis. And it’s our responsibility to tell stories and get people excited in a way that motivates them to think about the extinction crisis that’s unfolding right now,” said Beth Shapiro, professor of ecology and evolutionary biology. at the University of California at Santa Cruz. .

Shapiro is the lead paleogeneticist at Colossal Biosciences, a biotech and genetic engineering startup founded by tech entrepreneur Ben Lamm and Harvard Medical School geneticist George Church, which is working on equally ambitious plans to bring back the mammoth. woolly and the thylacine, or Tasmanian tiger.

Shapiro said she had already completed a key first step of the project – the complete sequencing of the dodo genome from ancient DNA – based on genetic material extracted from dodo remains in Denmark.

The next step was to compare the genetic information with the birds closest to the dodo in the pigeon family – the living Nicobar pigeon and the extinct Rodrigues solitary, a giant flightless pigeon that once lived on an island near Mauritius. It’s a process that would allow them to determine which mutations in the genome “make a dodo a dodo,” Shapiro said.

However, the subsequent work needed to resurrect the animal – programming the cells of a living dodo relative with the lost bird’s DNA – will be much more difficult. Shapiro said she hopes to adapt an existing technique used involving primordial germ cells, the embryonic precursors to sperm and eggs, which has already been used to create a chicken sired by a duck.

The approach involves removing primordial gem cells from an egg, growing them in the lab and editing the cells with the desired genetic traits before injecting them back into an egg at the same stage of development, she explained. .

Even if the team succeeds in this high-stakes endeavor, they won’t make an exact copy of the dodo that lived four centuries ago, but a modified hybrid form.

However, Shapiro said perfecting these synthetic biology tools will have broader implications for bird conservation. The techniques could allow scientists to move specific genetic traits between bird species to help protect them as habitats shrink and the climate warms.

“This technology, which works in chickens…. it would be amazing to make this work in many different birds across the tree of bird life because it will have a huge impact on bird conservation,” Shapiro said.

“If we find that there’s something that provides immunity against a disease that hurts a population, and you know what genetic changes underlie that immunity or that ability to fight that disease – maybe we can use these tools to transfer that even between closely related species,” she added.

Mike McGrew, senior lecturer and personal chair in avian reproductive technologies at the University of Edinburgh’s Roslin Institute, described the project as a “lunar launch for synthetic biology”. His job is to turn commercial laying hens into substitutes for rare chicken breeds resurrected from frozen primordial germ cells.

“The idea is that now you need to be able to do that with pigeon species. And that’s the hardest part of moving from chicken species, which a lot of labs around the world are doing, to other bird species,” said McGrew, who is not directly involved with the dodo project but is on Colossal’s science advisory board.

“I have been trying for about 10 years to grow germ cells from other bird species. It’s tough,” he said.

Whether or not Colossal and his team of scientists succeed in their quest to bring back the dodo and other extinct creatures, the de-extinction projects and technological breakthroughs they can generate are exciting investors. Colossal also announced on Tuesday that it has raised an additional $150 million, bringing the total amount raised since the company launched in 2021 to $225 million.

Critics, however, say the vast sums involved could be better spent protecting the nearly 400 species of birds, and many other animals and plants, which are listed as endangered.

“There are so many things that desperately need our help. And money. Why would you even try to save something that’s long gone, when there’s so much that’s hopeless right now? said Julian Hume, an avian paleontologist at the Natural History Museum in London who studies the dodo.

Hume said the dodo was very little known and many myths surround the creature. Even the origin of its name is a mystery, although it is believed to come from the sound of the call the bird is said to have made – a low-pitched, pigeon-like coo.

Millions of years ago, the ancestors of the dodo lived in Southeast Asia, and when the sea level was low, it jumped from island to island to Mauritius, where it became isolated without predators once the sea level rises.

“Flight is very (energy) expensive. Why bother maintaining it if you don’t need it? All fruits and food are on the ground, and when you can’t fly anymore, you can grow. That’s what the dodo did, it got bigger and bigger and bigger,” Hume said.

According to a 3D digital model of the Hume bird developed based on a skeleton from the Durban Natural Science Museum in South Africa, the dodo once stood around 70 centimeters (2.3 feet) and weighed around 15 to 18 kilograms. (33 to 39 pounds) .

The model revealed that the dodo was also likely more agile than the illustrations that depict it as might suggest a large, unsightly bird.

We have the dodo to thank for introducing the idea of ​​extinction to the world – a sad realization still felt in the phrase “dead as a dodo”.

In the 1600s, before the first dinosaur fossils were widely known, “the concept of extinction did not exist. Everything was God’s creation and they were here forever. The idea that something can be annihilated just wasn’t in anyone’s vocabulary,” Hume said.

“It was such an extraordinary bird, even at the time of its discovery,” he added. “They disappeared quickly. So when people wanted to know more about them, there was none.”