Scientists have reconstructed the most complete genome of a Tasmanian tiger to date, bringing them one step closer to reviving the species that has been extinct since 1936.
Historic Collection/Alamy Stock PhotoA pair of Tasmanian tigers in captivity.
In 1936, the world’s last thylacine, also known as the Tasmanian tiger, died in a zoo in Hobart, Tasmania. Now, a de-extinction company believes that it’s just a few steps away from bringing the species back to life.
If scientists succeed, they believe that the reintroduction of the Tasmanian tiger could benefit the Australian island’s ecosystem. And it was all made possible by the discovery of a 110-year-old thylacine head preserved in ethanol.
Inside The Tasmanian Tiger De-Extinction Project
Colossal BiosciencesResearcher Andrew Pask working on the Tasmanian tiger de-extinction project.
According to a press release from Colossal Biosciences — a company that is also working on reviving the woolly mammoth and the dodo — scientists are just steps away from bringing the Tasmanian tiger back from extinction.
Researchers from the company have been assisted in their effort by a 110-year-old Tasmanian tiger head that was found skinned and preserved in ethanol at a Melbourne museum. Using this artifact, scientists have been able to extract crucial RNA from the tiger’s tongue, nasal cavity, brain, and eye.
“This exceptional sample provides a fantastic opportunity for us to understand gene expression in thylacines,” Dr. Andrew Pask, the head of the Thylacine Integrated Genomic Restoration Research Laboratory at the School of BioSciences in the University of Melbourne said in the press release.
Pask continued, “With this new resource in hand we will be able to determine what a thylacine could taste, what it could smell, what kind of vision it had and even how its brain functioned!”
Andrew Pask/University of Melbourne and Museums VictoriaA preserved Tasmanian tiger head similar to the one Colossal Biosciences is using to de-extinct the species.
To fully replicate the Tasmanian tiger, the team is also working on editing the DNA of an animal called a fat-tailed dunnart, the thylacine’s closest living relative. Their goal is to edit the fat-tailed dunnart’s DNA into a thylacine’s DNA, and the company has already made more than 300 unique genetic changes — making it “the most edited animal cell to date.”
“The new thylacine genome is exceptional both in its contiguity — it is assembled to the level of chromosomes — and its accuracy — the genome is estimated to be >99.9% accurate, and even includes hard-to-assemble repetitive features such as centromeres and telomeres, which are challenging to reconstruct even for living species,” the Colossal Biosciences press release explains. “The genome has only 45 gaps, which will be closed by additional sequencing efforts in the coming months.”
So, how did the Tasmanian tiger go extinct in the first place? And why does Colossal Biosciences think it’s a good idea to bring the animal back to life?
The Human-Driven Extinction Of The Tasmanian Tiger
National Archives of AustraliaA family of Tasmanian tigers. The last of the creatures died in a Tasmanian zoo in 1936, and the species was declared extinct in the 1980s.
Tasmanian tigers roamed Tasmania for thousands of years. But in the 19th century, they were considered pests because they ate domesticated sheep. The government paid a bounty for Tasmanian tiger carcasses, and their numbers quickly plummeted. By 1936, just one thylacine was left. When it died, the species died with it.
As such, reintroducing it could be good for the Tasmanian ecosystem.
“It was a human driven extinction,” Pask explained to All That’s Interesting in an email. “Its ecosystem is still intact… It was a keystone species in the ecosystem. As our only mammal apex predator, the thylacine played an absolutely critical role in the ecosystem and when we hunted it to extinction there were no other species which could take its place. This has led to a destabilisation of the ecosystem in Tasmania already. This is an analogous situation to the removal of wolves from Yellowstone, which we know had impacts across the fauna, flora and landscape more broadly.”
As such, Pask believes that reintroducing the Tasmanian tiger could benefit the local ecosystem “enormously.”
“When the wolves were returned to Yellowstone valley 60+ years after their removal, the landscape was completely transformed back to its more stable biodiverse state,” Pask told All That’s Interesting. “Apex predators are necessary in any ecosystem and the loss of the thylacine was truly tragic for Tasmania, and made even more problematic because we don’t have any other mammalian predators to help compensate for its loss.”
But such a day is still a few years off. “De-extincting” the Tasmanian tiger remains a huge challenge — and something of a controversial one. Some believe that the millions of dollars being spent to revive lost species should instead be used to save living ones in danger of extinction.
Regardless, Colossal Bioscience seems to be charging ahead with its projects. Pask told All That’s Interesting that he imagines the first thylacine could reasonably be born “within a decade.”
After reading about the project to bring the Tasmanian tiger back to life, look through this list of animals that have sadly gone extinct. Or, learn about some of the Earth’s most incredible prehistoric animals.
