‘De-Extinction’ Company Will Try to Bring Back the Dodo

Genetic engineering company Colossal Biosciences said on Tuesday it would try to resurrect the extinct dodo bird, and it received $US150 ($208) million in new funding to support its “de-extinction” activities.

The dodo was already part of Colossal’s plans by September 2022, but now the company has announced it with all the pomp, circumstance, and seed funding that suggests it’s actually heading toward that goal. The $US150 ($208) million, the company’s second round of funding, was led by several venture capital firms, including United States Innovative Technology Fund and In-Q-Tel, a CIA-funded VC firm that first invested in the company sat. in September.

Adding the dodo to its official dossier brings Colossal’s total extinction targets to three: the woolly mammoth (the company’s first target species, announced in September 2021), and the thylacine, aka the Tasmanian tiger, the largest carnivorous marsupial.

Colossal’s stated goal isn’t simply to bring these creatures back for vibes; his claim is that reintroducing the species to their respective habitats will help restore some measure of normality to those environments.

Mammoths became extinct about 4,000 years ago on Wrangel Island, on the northeastern coast of Russia. The dodo, a species of wingless bird native to the island of Mauritius, was gone by 1681. The last known thylacine died in 1936 at a zoo in Tasmania. Scientists have the genomes of all three species – the mammoth’s in 2015, the dodo’s in 2016, and the thylacine’s in 2018.

The latter species have been driven to extinction by mankind; humans have hunted the dodo, introducing predators and pests into its environment and contributing to its habitat loss. Humans may also have played a role in mammoth extinction, but the dodo and the thylacine are classic examples of our ability to wipe out species at extraordinary speeds.

After the European colonization of Tasmania, settlers cast the thylacine as a threat to sheep flocks (although this threat was vastly overblown), and the Tasmanian government eventually placed a bounty on the marsupial’s head. Some experts believe the thylacine may have persisted in the wild for several decades after 1936, but the writing was on the wall for the iconic species.

Colossal also said it is creating an Avian Genomics Group, which will oversee efforts to resurrect the chunky dodo. The blue-grey bird weighed as much as 23 kg and had a distinctive curved beak. Perhaps due to the lack of natural predators on Mauritius, the dodo has evolved to be flighty. Europeans encountered the birds in 1507, and about 150 years later they were extinct.

If the company’s work pans out — and it’s a big if — proxy species of those extinct animals will be brought. This is because the genetically engineered animals produced by Colossal would not be a bonafide mammoth, dodo or thylacine.

In 2016, the International Union for Conservation of Nature’s Species Survival Commission published a report outlining ground rules for creating proxy species. “Proxy is used here to mean a substitute that in some sense (eg, phenotypically, behaviorally, ecologically) would represent a different entity—the extinct form,” the commission said, adding that “Proxy is preferred over facsimile, which is the creation of an exact copy.”

De-extinction is somewhat of a misnomer, as this process, if successful, would yield science’s best analogue for an extinct creature, not the creature itself as it existed in the past. De-extinction methods generally rely on the use of a living being’s genetics in the resurrection process. This means that any 21st century mammoth will have at least some modern elephant DNA, and any emerging thylacine will be produced from the genome and egg of a related species.

According to National Geographic, Colossal intends to produce its proxy mammoth from an artificial womb rather than using an endangered Asian elephant.

What’s more, behavioral traits of an animal are impossible to extrapolate from a genome alone. How will we know if the mammoth we produce actually behaves as the originals did? Fortunately, there is video of thylacines, but other details of the animal—such as the circumstances that may have elicited one of its trademark double-yip vocalizations, of which there are no recordings—are lost.

A good reference for the colossal work is a paper published last year in Current Biology, in which a team of geneticists developed a proof-of-principle model for the revival of the Christmas Island rat, a species which is closely related to the extant Norway brown rat.

The team was confident that they could reproduce aspects of the extinct rat where areas of the two animals’ genomes largely overlapped; namely genes involving keratin and details such as fur color and the shape of its ears. But genes related to the extinct rat’s sense of smell (its sense of smell) and its immune responses had little effect in the genome of the living Norway rat. So if the team wanted to bring the rat back in some form, it would need a faked immune response and olfactory system.

Similarly, it would be difficult to know whether a proxy thylacine, dodo or mammoth behaves as a bonafide version of the animal might have behaved. Many animal behaviors are learned from parents, but a resurrected mammoth will be alone in the world.

The current plan for the thylacine is to plant the nucleus of a “Thilacine-like cell” into the egg of a genetically engineered Dasyurid egg. Dasyurides are a group of marsupials that includes quolls that the Colossal team deemed best suited for a thylacine redux. The host Dasyurid’s genome would be engineered to make it more “Tylacine-like,” according to Colossal’s website.

Whether or not proxy species are actually produced by startups like Colossal, genetics research done in the name of creating them can help us better understand the relationships between species and how to protect living things from threats like disease.

Better understanding of species – extinct and extant – at a genetic level is a good thing. How that technology is used, and by whom, is an issue that needs to be handled carefully.

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