* This is Part 2 of a two-part essay written by Risa Aria Schnebly. Risa is a PhD candidate at Arizona State University interested in (de-)extinction and conservation.
You can read Part 1 of this essay here…
Breeding Back the Zebra Without Stripes
As a young boy, the prospect of seeing an extinct creature must have been world-bending. Especially if that extinct creature was the fierce and giant aurochs, the stuff of Teutonic myths and Cesarean legends. Perhaps that’s how Reinhold Rau felt as a school boy in the 1930s, when he saw one of Lutz Heck’s back-bred aurochs at the Berlin Zoo (see Part 1 for more on aurochs back-breeding) (Heywood, 2015). No matter what Rau felt, the sight of a back-bred aurochs clearly stayed with him; he later wrote that the experience left him “immensely… impressed” (Rau, 1982). Decades later, Rau attempted a similar project using back-breeding techniques similar to the Heck brothers’. Rather than trying to recreate a European species, though, Rau took his project overseas to South Africa, where he attempted to recreate the extinct quagga.
Quaggas were a subspecies of zebra endemic to South Africa that went extinct in 1883 when the last captive quagga died in an Amsterdam zoo. Quaggas looked a lot like zebras, with typical zebra stripes on their head and neck. Below the neck, however, the stripes fade into a reddish brown body. In the decades leading up to the quagga’s extinction, South Africa was seen as a “hunter’s paradise,” where Europeans would settle or travel to in order to enjoy hunting expeditions. Hunters sold quagga meat as food and hides as leather, and colonial governments aimed to eradicate the species for fear that it would compete with livestock. As a result, colonists quickly hunted the species to extinction (Rau 1974).
Lutz Heck was the first to propose back-breeding the quagga in his book Animals, My Adventure. Suspecting that the quagga was just a subspecies of plains zebra with different coloration, Lutz proposed to recreate the quagga by breeding other species with similar coloration or stripe patterns. No one attempted to carry out Lutz’s proposal for decades, though.
A preserved quagga from the collections of the Senckenberg Nature Museum in Frankfurt
While Rau had back-breeding on the brain since childhood, he did not attempt it himself until late in his career. Rau trained as a fossil preparator at the Senckenberg Museum in the 1940s, and transferred to the South African Museum to work as a taxidermist in 1959. There, he was charged with examining and preserving taxidermied specimens like the quagga. While inspecting the museum’s quagga specimens, he noticed that they were badly preserved; the past taxidermist had not properly cleaned the specimen, and as a result it still had some muscles, tissue, and blood vessels (McNeill, 2006). The poor work of the preceding taxidermist was a blessing in disguise for Rau, though, who embarked on a mission to collect tissue samples for quagga specimens across Europe.
Rau held onto the quagga tissue samples until 1981, when biotechnology tools had advanced to the point that genome sequencing became a possibility. Rau sent the quagga tissues samples to geneticists at the University of California, Berkeley, and the San Diego Zoo, who analyzed the quagga’s mitochondrial DNA and found that it was closely related to species of plains zebra (Rau 1982; Hewood, 2015). That evidence confirmed Lutz Heck’s suspicion from decades before: the quagga was indeed a subspecies of zebra, suggesting to Rau that modern zebras could be “bred back” to recreate the quagga.
In 1987, the Cape Department of Conservation offered Rau a farm north of Cape Town to conduct his breeding experiments. The South African Museum, University of Cape Town, and the South African Nature foundation donated money to start what became The Quagga Project. Rau led efforts to capture zebras just north of the region where quaggas once lived in the belief that those zebras would be the most genetically similar to quaggas. Soon after, Rau started selectively breeding the captured zebras. The program went on for decades, with Rau managing herds in various locations, and in 2005, Rau finally witnessed the birth of a new foal that looked very much like a quagga.
Left: an illustration of a quagga. Right: Reinhold Rau with his back-bred “quagga” calf
Though Rau died in 2006, The Quagga Project continues. As of 2023, they are on their fifth generation of foals. In 2016, the Quagga Project produced offspring that they deemed sufficiently “quagga-like” to warrant the name “quagga”. They named this generation of foals the “Rau quaggas,” and declared their resurrection efforts a success. That year, Eric Harley, the Project head at the time, said in a CNN interview that “if we can get animals which everybody agrees look like the quagga, then indeed we can say the quagga was never really extinct….” and “if we can retrieve at least the appearance of the quagga then we can say we’ve re-righted a wrong when settlers came out and shot everything in sight” (Page and Hancock, 2016). Harley’s remarks show how, despite limits on how genetically close the recreated organisms can be to their extinct predecessors, recreating an extinct phenotype is enough to qualify as atonement (for some).
Back-breeding projects like the Quagga Project and the Tauros Programme, which uses back-breeding to create new aurochs, are set to continue as of 2023, despite how limited the degree of genetic similarity such projects can achieve. The next wave of resurrection biology projects, however, went in the opposite direction: prioritizing genetic identity by using cloning techniques.
The Rise of Cloning: “Resurrecting” the Thylacine
On July 5, 1996, Scottish scientists at the Roslin Institute made headlines by doing what had previously been the stuff of science fiction: successfully cloning an adult animal, leading to the birth of Dolly the sheep. After Dolly’s birth, scientists around the world quickly started considering the many ways they could use cloning technology. It only took a few years for scientists to create a project with the goal of using cloning to help protect endangered species, and even to bring lost species back to life.
In September 1999, the Australian Museum launched a project to clone the thylacine, or Tasmanian tiger, a marsupial that was driven to extinction by European colonists in 1936. Colonists believed the carnivorous creature was killing their livestock. The Tasmanian government instituted bounties incentivizing colonists to hunt the thylacine, which rapidly diminished populations of the creature across Tasmania, the only place thylacines lived. The last known thylacine died in the Hobart Zoo in Tasmania as a result of neglect; zookeepers at the underfunded zoo forgot to unlock the thylacine’s enclosure, leaving it locked outside overnight, where it froze to death.
A photograph of the living last thylacine, who died at the Hobart Zoo in 1936. https://www.nma.gov.au/defining-moments/resources/extinction-of-thylacine
The last thylacine’s death went largely unnoticed; Australians still believed there were more thylacines living out in the remote Tasmanian bush somewhere, waiting to be found. But after decades of failed searches for the thylacine, the International Union for the Conservation of Nature declared the thylacine extinct in 1986. Despite many Tasmanians holding onto the belief that the thylacine is not actually extinct, with many reported ghost sightings of the creature, the declaration of its extinction led to an intense period of public mourning. The thylacine became known as a symbol of Tasmania, and its death was taken to epitomize humanity’s baleful influence on the planet (Paddle, 2000).
The intense mourning in Tasmania lent power to the idea of “bringing back” the thylacine through cloning. Mike Archer, the director of the Australian Museum and head of the Thylacine Cloning Project, argued there was a “moral imperative” to clone the thylacine and lift the “complex web of guilt” that resulted from its extinction (Greer, 2009). The Project immediately was the subject of intense media coverage, which scrutinized the feasibility and ethics of cloning with familiar arguments about scientists “playing God” and references to Frankenstein and Jurassic Park. However, as many commentators lauded the Project’s efforts to push the bounds of science, and rejoiced at the idea of having a beloved species restored to them (Fletcher, 2008).
Despite the mixed public views, the mass media attention brought the Project nearly half a million dollars in funding. Project scientists used the funds to attempt to clone DNA from a preserved thylacine specimen from 1886. In 2003, they successfully used PCR to replicate individual thylacine genes, but ultimately, the DNA was too degraded to clone a complete animal. After years of attempts, the Project disbanded in 2005. But by that time, another extinct animal cloning project had taken place that renewed hope that scientists might indeed be able to bring extinct species back from the dead.
Spanish Bucardos: The Only Species to Go Extinct Twice
The same year that Australian scientists launched their project to clone the thylacine, on the other side of the world, Spanish conservationists were carefully monitoring the last living Pyrenean ibex, or Spanish bucardo: a kind of mountain goat that lives in the Pyrenees mountains between France and Spain. Bucardos, like many charismatic extinct creatures, were driven to the brink by European hunters. As the bucardo became increasingly rare, it also became an increasingly prized trophy by hunters. The last bucardo was a female named Celia, whom Spanish scientists trapped and collared to monitor her movements. In 2000, nine months after scientists had collared Celia, the radio signal from her collar started making a long, ringing noise––the signal that she had died (Fernandez-Arias, 2013). The team went to find Celia, and found her body crushed by a fallen tree. The last living bucardo had died, leaving the species extinct.
Celia, the last Spanish bucardo, on display at the reception centre of the National Park of Ordesa and Monte Perdido in Aragon
When the Spanish team originally trapped Celia, though, they didn’t just collar her; they also took a sample of tissue cells from her ear, and cryopreserved them (Choi, 2009). Two years after her death, a team got to work trying to clone the DNA from Celia’s tissue, which was in good enough condition to make the attempt, unlike the DNA from the thylacine (which was over 100 years old). In 2003, they transferred 154 bucardo embryos into 44 spanish ibex and hybrid goats. Seven got pregnant, but only one hybrid goat carried the embryo to term. In July 2003, the team of scientists succeeded: Celia’s clone was born by C-section, meaning the team had managed to bring an extinct species back to life. But that success was short-lived; Celia’s clone was born with a deformed lung, and died after only seven minutes (Fernandez-Arias, 2013). That makes the bucardo not only the species to have been officially “brought back,” but also the only species to go extinct twice.
The Spanish team published the results of their cloning experiment in 2009, and have not published any more reports of cloning attempts since. In 2012, Alberto Fernandez-Arias, the head of the bucardo cloning team, announced that they were partnering with a new biotechnology nonprofit called Revive & Restore, declaring that the teams had the mutual goal of creating a de-extinct bucardo population that could be reintroduced to the Pyrenees. However, neither Revive & Restore nor the Spanish team have published any updates on bucardo de-extinction since that announcement.
Reviving, Restoring and Getting Colossal
Though little more has been said about the bucardo, Revive & Restore stayed in the headlines. Fernandez-Arias announced his team’s partnership with Revive & Restore at a TEDx event that the nonprofit organized in 2013 to announce the launch of several de-extinction projects and to begin a public conversation about their work. The event featured talks from a range of colorful characters, from Mike Archer, the former head of the Thylacine Cloning Project, to Beth Shapiro, an animated ancient DNA researcher at UC Santa Cruz, and George Church, a Harvard geneticist with a fluffy white beard who’s been lauded over and over again as one of the maddest scientists of our times. The event also featured talks from Revive & Restore’s founders, Ryan Phelan and Stewart Brand, an eccentric wife and husband duo. Phelan is a tech entrepreneur who’s created various startups prior to Revive & Restore, including the company Direct Medical Knowledge, which eventually became WebMD. Brand, her husband, is a techno-hippy who went from running around with Ken Kesey, organizing acid trips and music festivals in the 1960s, to running the Whole Earth Catalog, a counter-culture magazine, and backing other technological conservation solutions in the twenty-first century.
Beth Shapiro, a prominent de-extinction scientist
The year prior to the TEDxDeExtinction event, Phelan and Brand launched Revive & Restore with a flagship project to de-extinct the passenger pigeon, an icon in the US conservation movement. Passenger pigeons once numbered in the billions in the eastern US. When a flock of the birds flew overhead, the sky turned dark for up to two hours as flocks as wide as two whole miles passed through. The birds were so abundant that their populations seemed infinite, and the hunters who shot them down by the dozens never imagined that their actions could have any long-term effect. But by the turn of the twentieth century, the birds had become increasingly rare. Whenever reports of a lingering flock emerged, hunters would descend on the pigeons for a chance to reap the motherlode once more. The hunting, as with every other species I’ve considered, led to the species’ extinction. In 1914, the last passenger pigeon, named Martha, died in her enclosure in the Cincinnati Zoo (Barrow, 2009).
As with the thylacine cloning project, the intense mourning conservationists had expressed over the extinction of the passenger pigeon lent emotional power to the idea of bringing the species back. When Brand gave his TEDx talk on the project (which took place on the eve of the 100th anniversary of the pigeon’s extinction), he leaned into the idea that de-extinction could be some sort of atonement, saying the technology could allow us to bring species back to “a world that misses them” (Brand, 2013).
After the TEDx event, the term “de-extinction” was all over the news. The media blew up with those all-too-familiar headlines challenging the permanence of extinction and making endless references to Jurassic Park. From within the media storm, thought pieces and academic articles about the meaning of extinction began to emerge, calling scholars to think more deeply about the biological concept that, despite being central to fields like conservation and paleontology, has been the subject of little philosophical attention.
In 2021, George Church co-founded a biotechnology company called Colossal with Ben Lamm, an entrepreneur based in Dallas. Colossal launched the company by taking over the Wooly Mammoth De-Extinction Project, which Church had previously been heading for Revive & Restore. Since launching, Colossal has raised hundreds of millions of dollars from big-name donors (many from Silicon Valley), and has also launched two more de-extinction projects: one to use genetic engineering to recreate the thylacine (a project headed by Andrew Pask at the University of Melbourne), as well as a project to de-extinct the famously dead dodo led by Beth Shapiro. They promise to have a de-extinct mammoth and thylacine by 2028.
An image from Colossal’s website, showing the woolly mammoth, the dodo, and the thylacine emerging from a piece of scientific glassware, here imagined as a portal connecting our world to the past
On their website, Colossal employs lots of rhetoric that perpetuates the idea of de-extinction as a sort of atonement or redemption, holding up genetic conservation technologies as a way of “reversing the problems that humans created,” and undoing the harm that humanity has caused (Colossal). Could the continuation of such rhetoric lull the public into believing that technology will be able to fix humanity’s mistakes, and absolve us from having to undergo large-scale societal changes needed to live more gently on the earth? Some critics think so (Clayton, 2015; Campagna, 2017; Minteer, 2019), though de-extinction scientists have dismissed such worries (Brand, 2014; Novak, 2018). And to their credit, Colossal uses their hundreds of millions of donations to do more than just work towards de-extinction; they also have elephant conservation projects, working to develop tools that can protect elephants and from viruses, and they’ve partnered with the Mauritian Wildlife Foundation to help restore a habitat where their de-extinct dodo may one day live. Hopefully, de-extinction efforts will uplift other conservation projects as they continue to get more attention and funding.
A screen grab from Colossal’s website, touting de-extinction as the solution to the ongoing biodiversity crisis
To Live with The Dead
Within our lifetimes, our world may again see creatures that resemble those that have only existed in photographs, as taxidermied specimens, or as corpses extracted from the arctic tundra. Dodos, thylacines, mammoths and passenger pigeons have been little more than fictional characters in most of our lives, but soon there may be dodos–– or at least some dodo-like birds–– awkwardly waddling through some conservation center in Mauritius, or giant mammoth-elephant hybrids lumbering through the Siberian tundra. Without any of the members of the species these creatures are supposed to represent, how will they adapt to their environments and to each other? Will we even consider them as the same species as their extinct counterparts?
Question abound. How will the public react to de-extinct creatures? Will their existence make us feel like humanity has redeemed itself for all the destruction it has caused? How will that influence the position of conservation in the social imagination as the world continues to warm and more and more species continue to be lost?
These questions are presently unanswered. Philosophers of science, conservationists, science communicators, and members of the public all have a role to play in untangling these questions and deciding what the right answers are. De-extinction is happening, backed by hundreds of millions of dollars and relying on technology that advances with each passing day. It’s not a question of whether or not scientists should go through with de-extinction anymore, it’s a matter of how we will understand the creatures created through these processes and what meaning we will ascribe to the project of “de-extinction” itself. The way we position, define, and discuss it may influence the kinds of projects scientists pursue in a world that is increasingly of human making, as well as what the public thinks about humanity’s obligations to the non-human world.
Scientists and naturalists have been fascinated with the idea of cheating death for hundreds of years, and over the last two centuries, these fascinations have been funneled into the project of resurrection biology. Now, we’re living at a time when scientists may finally manage the trick. Hopefully, the projects will end up as more than mere public marvels, and will contribute to forging the better world imagined by their rhetoric.
References
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Brand, S. 2013. Stewart Brand: The dawn of de-extinction. Are you ready? TED, 18:24. Posted on March 13, 2013. https://www.ted.com/talks/stewart_brand_the_dawn_of_de_extinction_are_you_ready?language=en#t-997210
Brand, S. 2014. De-extinction debate: should we bring back the woolly mammoth? Yale e360, January 13, 2014. https://e360.yale.edu/features/the_case_for_de-extinction_why_we_should_bring_back_the_woolly_mammoth
Campagna, C., Guevara, D., & Le Boeuf, B. 2017. De-scenting extinction: the promise of de-extinction may hasten continuing extinctions. Hastings Center Report 47:S48–53.
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McNeill Jr., D.G. Reinhold E. Rau, taxidermist on a quest, dies. New York Times, March 23, 2006. https://www.nytimes.com/2006/03/23/world/africa/reinhold-e-rau-taxidermist-on-a-quest-dies.html
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Page, T. & Hancock, C. 2016 Zebra cousin went extinct 100 years ago. Now, it’s back. CNN, January 27, 2016. https://www.cnn.com/2016/01/25/africa/quagga-project-zebra-conservation-extinct-south-africa/index.html
Pask, A. Quoted in “Would you like to see a Tasmanian Tiger or thylacine returned from extinction?” ABC Australia, September 6, 2023. https://www.youtube.com/watch?v=kgdTvUjh1Nk
Rau, R. Revised list of the preserved Mlmaterial of the Elextinct Cape Colony Quagga, Equus Quagga Quagga. Annals of the South African Museum 65:41–85. https://www.biodiversitylibrary.org/page/40928201#page/67/mode/1up
Rau, R. 1982. Rough road towards rebreeding the quagga: how it came about. (Unpublished manuscript). https://www.quaggaproject.org/downloads/2012/rough%20road%20to%20re%20breeding%20quagga-1.pdf
Revive & Restore. “De-Extinction.” https://reviverestore.org/category/de-extinction/