Resurrecting the dodo: an ethical dilemma or chance at restoring biodiversity? 

What do woolly mammoths, dire wolves, and dodos have in common? Well, they’re all characters in the movie franchise Ice Age, and they’re all extinct. But not for long, according to researchers at Colossal Biosciences. In fact, the dire wolf has already been resurrected, as the ‘de-extinction’ company plans to revive all these animals that have gone extinct. Now, a recent major breakthrough could see the flightless dodo bird brought back to life soon. However, opinions are split, as some conservationists believe that this will aid restorative justice, while critics think it is a hubristic plan to begin with. 

Colossal Biosciences’ breakthrough a step closer to reviving dodo 

Researchers at Colossal Biosciences revealed they’ve made a “pivotal step” in bringing back the flightless ground-dwelling pigeon, which went extinct around 350 years ago. It has grown pigeon cells called primordial cells, which are precursors to eggs and sperm, which eventually grow into a new organism, in this case, a dodo. 

This is only the beginning of Colossal’s dodo bird de-extinction journey. It doesn’t want to just genetically engineer one dodo. It wants to create thousands of them.  

All this has sparked intrigue among investors, even the likes of Hollywood. The company has nabbed $120 million for bringing its dodo mission to life, with investment from filmmaker and Lord of the Rings director Peter Jackson. It has also previously been backed by other celebrities such as Paris Hilton, Tom Brady, and Tiger Woods. 

However, according to Colossal’s chief executive officer (CEO) and co-founder Ben Lamm, it is beyond the buzz around the novelty of de-extinction, it’s about restoring biodiversity. 

“We’re not just bringing back animals. We’re restoring lost ecological functions,” said Lamm. 

Dodo birds de-extinction: can these Mauritius natives be brought back through genetic engineering? 

Dodos were once endemic to the island of Mauritius and wandered the forests with no natural predators on the isolated island. Often thought to be poorly adapted birds doomed to die, this wasn’t the case at all. These descendants of tropical pigeons were not at risk of being killed by any predators on the island, so their flight muscles shrank over time. The species survived droughts – albeit many died – but it was when human beings arrived that everything changed for them and led to their ultimate demise. 

Apart from being eaten by the sailors who came to the island, their land was also taken away from them, and they had to fight for resources with grazing animals that were brought in by the sailors. Less than a hundred years after humans stepped foot into the forests of Mauritius where dodos foraged, the species had become extinct. 

“When key species go extinct, entire ecosystems can collapse. Large herbivores shape grasslands, seed dispersers maintain forests, and predators control prey populations. These ecological roles don’t disappear when a species dies, they just go unfilled,” said Lamm. 

Lamm and scientists at Colossal think that de-extinction could undo some of this damage that has been done. 

“De-extinction repairs these gaps by rebuilding natural processes that took millions of years to evolve. For biodiversity, this creates a multiplier effect. One restored keystone species can support dozens of other plants and animals that depend on the ecological functions it provides. We’re not just adding one species back but potentially saving many others that need those restored ecosystem services to survive,” said Lamm. 

The dodo revival by culturing primordial cells is only the third time it has been done, after chickens and geese. Having now grown the cells, the company plans to employ CRISPR gene editing technology to edit the cells of the pigeons to make them more dodo-like.  

The gene-edited pigeon cells will then be transferred into the embryos of chickens, which will act as surrogates to give birth to the dodos. Although it would have been easier if pigeons could be the surrogates themselves, chickens are preferred as surrogates because they are flightless, and so won’t fly away. Plus, genetic engineering has previously been practiced on chickens before.  

It could take around five to seven years for a dodo to step back into Mauritius, Colossal Biosciences confirmed. The dodo bird revival is part of broader de-extinction plans, some of which came to fruition with the return of what Colossal claims are dire wolves earlier this year. 

Gene-edited gray wolves or extinct dire wolves? The science behind it 

Having retrieved DNA from a 13,000-year-old tooth and 72,000-year-old skull, it used gene editing to make dire wolf puppies. Colossal’s process is less invasive than traditional cloning, the technology known for creating Dolly the sheep, the first mammal cloned in 1996. 

Traditional cloning involves taking cells from animal tissues from which the DNA is taken and injected into a donor from the same species that then develops into an embryo. The embryo is implanted into a surrogate animal who carries it until it gives birth to the organism whose cells were taken in the first place. 

The Texas-based startup’s technique is different in that it extracted progenitor cells from blood samples of gray wolves, which are alive and well. Then, it edited 14 genes from their DNA to express certain traits of dire wolves that vary from gray wolves. For instance, dire wolves have a light coat color and three genes code for it. But these genes in gray wolves can result in deafness and blindness. So, Colossal Biosciences silenced the other two genes, keeping the coat a light color but not harming them. 

Then, the scientists took these engineered cells and placed them in egg cells, which grew into embryos that were then transported to wombs of hounds. These surrogates gave birth to Romulus, Remus, and Khaleesi after 65 days in the womb. Now, as Remus and Romulus turn a year old next week, and Khaleesi eight months, they chase and tussle in a protected ecological reserve but are incapable of existing in the wild as they were hand reared.  

“It is a sense of pride, excitement, joy, and wonder. I could not be prouder of our incredible team for their history-defining work,” said Lamm. “The feeling is beyond words. To hear a dire wolf puppy’s howl that has not been heard in over 12,000 years stirs something deep in you.” 

While this garnered a lot of attention, many critics are not pleased. Some have questioned calling these animals ‘dire wolves,’ as they say that these are just gray wolves that have been genetically modified, and the actual extinct species has not been brought back.  

The ethical implications: is de-extinction a distraction from a conservation crisis? 

Others have challenged the ethics of it all. Researchers have claimed that de-extinction is morally wrong and that it will cause unnecessary suffering. Calling these genetically engineered animals ‘zombies,’ critics like Heather Browning, a lecturer in philosophy at the University of Southampton, have questioned whether the welfare of these animals has actually been taken into consideration. 

“De-extinction could lead to ‘miscarriage, stillbirth, early death, genetic abnormality, and chronic disease’ as the result of cloning. And these are just the beginnings of the ethical issues since there are others regarding rearing and reintroducing these animals,” said Browning in her research paper. 

Another critique against de-extinction is the argument that it is hubristic in nature.  

Attempting to revive lost species is in many ways a refusal to accept our moral and technological limits in nature, according to Ben Minteer, professor of environmental ethics at the University of Arizona.  

The most pressing argument is that behind the allure of bringing back a long-gone species, actual conservation efforts could be stalled, and funding might be stripped away. Conservation is underfunded as it is, and there are delays in protecting endangered species, let alone ones that are being revived from extinction. Jamie Rappaport Clark, American conservationist and former CEO of Defenders of Wildlife, pointed out that de-extinction could just hamper conservation efforts and prompt defunding, in a report by KQED. 

“They’ll say, ‘We shouldn’t be funding recovery and preventing the extinction of species because we have a way out,’” she said in the report. Instead of trying to what has now come to be known as “genetically rescuing” dead animals, why not allocate the funds towards taking care of the ones we’ve got? It’s the sentiment that Clark has.  

However, for Lamm, de-extinction is a path towards conservation, and he thinks that preserving biodiversity and de-extinction go hand in hand. 

“There are many different ethical concerns people raise, including animal welfare, environmental risks, and resource allocation, and we take them all seriously. Our approach prioritizes rigorous safety protocols and animal welfare at every step,” said Lamm. 

Proponents of the science argue that since humans drove the extinction of animals, humans are morally obligated to restore justice, according to research published in Cambridge University Press. Some believe that de-extinction is a means to restore species and that if we have the tools to get there, it’s at least worth a try. 

Preserving natural habitats: does de-extinction have a role to play? 

“There’s a critical ethical question that too often gets overlooked: what’s the moral cost of letting ecosystems continue collapsing when we might have tools to help? We’re in the middle of a biodiversity crisis that’s accelerating every year,” said Lamm. 

One million of the world’s estimated 8 million species of plants and animals are currently threatened with extinction, according to a report by the United Nations Environment Programme in 2022. With global funding shortages, including U.S. cuts to conservation nonprofits imposed this year, it could leave vulnerable species at a greater risk earlier than imagined. 

Aside from Colossal Biosciences, attempts to revive species are being made by the California-based nonprofit Revive & Restore. It is working on ‘genetically rescuing’ passenger pigeons and heath hens with the help of technologies such as genomics, CRISPR-Cas9 editing, cloning, and stem cell research. Other organizations like the San Diego Zoo Wildlife Alliance in the U.S. and the European Association of Zoos and Aquaria (EAZA) in the Netherlands, are also closely working with geneticists and biologists in gene editing in a bid to safeguard threatened species. The former has also created a biobank of genetic material from over 10,000 species that include extinct ones, that will serve as a source for cloning genetic engineering projects. 

Meanwhile, Colossal Biosciences wants to do the same with the woolly mammoth by 2028, as well as other extinct species like the moa bird and the Tasmanian tiger. And while it has embarked on its journey to bring back the dodo and will now clone the primordial cells it has grown, Colossal Biosciences wants to partner with the Mauritius government to rewild the birds back to what was once their natural habitat.  

Lamm said: “If our biotechnologies could restore ecological functions and prevent further species loss, do we have an ethical obligation to explore that responsibly? Different people will draw different ethical lines based on their values and worldviews. From our perspective, using science to repair ecological damage we’ve caused is taking responsibility for harm we’ve done and working to heal it.”