The resurrection of the Tasmanian Tiger
From The Guardian
Scientists in Australia and the US have launched an ambitious multimillion-dollar project to bring back the thylacine, a marsupial that died out in the 1930s, and reintroduce it to its native Tasmania.
The thylacine, also known as the Tasmanian tiger, is the second undertaking by Colossal, a Texas-based biotechnology “de-extinction” company that last year announced it planned to use genetic engineering techniques to recreate the woolly mammoth and return it to the Arctic tundra.
Its new project is a partnership with the University of Melbourne, which earlier this year received a $5m philanthropic gift to open a thylacine genetic restoration lab. The lab’s team has previously sequenced the genome of a juvenile specimen held by Museums Victoria, providing what its leader, Prof Andrew Pask, called “a complete blueprint on how to essentially build a thylacine”.
The thylacine was Australia’s only marsupial apex predator. It once lived across the continent, but was restricted to Tasmania about 3,000 years ago. Dog-like in appearance and with stripes across its back, it was extensively hunted after European colonisation. The last known survivor died in captivity in 1936. Despite many reported sightings in the decades that followed, and some quixotic attempts to prove its ongoing existence, it was officially declared extinct in the 1980s.
The scientists aim to reverse this by taking stem cells from a living species with similar DNA, the fat-tailed dunnart, and turning them into “thylacine” cells – or the closest approximation possible – using gene editing expertise developed by George Church, a professor of genetics at Harvard Medical School and Colossal’s co-founder. New marsupial-specific assisted reproductive technologies will be needed to use the stem cells to make an embryo, which would be transferred into either an artificial womb or a dunnart surrogate to gestate.
Pask said the partnership was the most significant contribution ever made to marsupial conservation in Australia as more than 30 scientists worked to accelerate the “massive grand challenge” of bringing the thylacine back from the dead. He believed the first joeys could be born in 10 years.
Colossal’s chief executive and other co-founder, the tech and software entrepreneur Ben Lamm, was more bullish, believing it was possible in less than six years, the timeframe that the company had set itself to produce the first set of mammoth calves.
“I think it’s highly probable this could be the first animal we de-extinct,” Lamm told the Guardian.
The challenges faced by the project are significant, and the scientists acknowledge several breakthrough steps will have to land for it to succeed. On reproductive technology, Pask said: “We are pursuing growing marsupials from conception to birth in a test-tube without a surrogate, which is conceivable given infant marsupials’ short gestation period and their small size.”
If successful, the plan would be to introduce the animal in a controlled setting on Tasmanian private land with an eventual goal of returning it to the wild. Pask said the researchers said they saw the work as not just bringing back long-dead species, but helping develop technology that could be applied to addressing today’s global extinction crisis.
|Photograph: National Film and Sound Archive of Australia|