Resurrecting the Thylacine: Does it Exist or Will Science Help?

Australian wildlife scientists have re-opened the cryptic case of the Tasmanian tiger, a marsupial carnivore that resembled a striped coyote and which was last seen alive more than 70 years ago.

Scientists think chances are slim that Thylacinus cynocephalus still roams remote areas of Tasmania, the large island just south of Australia, but they can't help but turn over every possible leaf for evidence.

The last wild Tasmanian tiger was killed by a farmer around 1930, and the last captive died in 1936 at the Hobart Zoo in Tasmania's capital. Fifty years later, the species was declared extinct.

The extinction marked the end of the family Thylacinidae, and of the world's largest marsupial carnivore. The Tasmanian tiger weighed about 65 pounds, had a nose-to-tail length of six feet and had several vertical stripes running across its lower back and tail.

Despite the official extinction, rumored sightings of the creature have continued to emerge from Tasmania's temperate forests.

Zoologist Jeremy Austin of the Australian Center for Ancient DNA and his colleagues are examining DNA from animal droppings, or scats, found in Tasmania in the late 1950s and 1960s, which have been preserved in the Tasmanian Museum and Art Gallery.

Eric Guiler, a thylacine expert who found the scats, told Austin the droppings probably came from a Tasmanian tiger rather than a dog or two common related marsupial carnivores — the well-known wolverine-like Tasmanian devil and the cat-like spotted quoll.

"If we find thylacine DNA from the 1950s scats it will be significant," Austin said. "This would prove that either the thylacine produced the scat or a [Tasmanian] devil ate a thylacine and dropped the scat. Either way, that is proof that the thylacine was there at the time."

If they were to find evidence the Tasmanian tiger was still extant in the 1950s, that would mean the beast was able to stay hidden from humans for at least 20 or 30 years.

"If they could survive this long with no real physical proof, then it does add a little more hope to the possibility that they could survive another 50 years without ever being caught, killed [or] hit by a car," Austin told LiveScience. "This chance is of course not great, but the glimmer of hope is ever so slightly brighter."

"We Still Receive at Least Two Credible Thylacine Sightings a Year"

A sighting of a thylacine near Cradle Mountain in Tasmania was recently reported. "I got a call the other day from two shooters near Cradle Mountain who had to have seen a thylacine, or they are lying," Mr Mooney said. "They were probably spotlighting illegally so there doesn't appear to be a motive for them to lie. The location was perfect and their description faultless."

Tasmanian tiger sightings in Victoria has reignited the theory that the species may have been introduced to the mainland before it became extinct in this state.

Victorian farmer Harry Cook owns a property bordering the Otway Ranges south of Melbourne.

Late last year he was with a mate inspecting crop damage caused by rabbits when they spotted three wedge-tailed eagles circling the paddock.

"They were circling over an animal -- we got within 12 foot of it. It was about the size of a large dog with a very long tail that was sticking straight up in the air as if it was fending off the wedgies," Mr Cook said.

"There were white stripes on its chest and it had a boofy head with round ears and the side of the muzzle was white."

He copped a lot of flak for reporting the peculiar sight, but not because no one believed him.

"Farmers around here told me I had broken the code of silence -- that they had seen things too, but as soon as it is reported all the townies come with their rifles trying to shoot it."

Mr Cook is not alone in experiencing such a sighting.

A former engineer, who did not want to be named, said he saw a dog-like animal in his headlights near Torquay in May 2006.

He described it in minute detail, from its slender body and fluid movements to the prison bar "salt and pepper" coloured stripes on its flanks.

"I can guarantee you there is a feral animal of some sort out there with short hair and stripes on the side; if someone says that description matches a tiger than I would say it is a tiger," he said.

Amateur researcher Michael Moss has logged eight recent sightings near Geelong, in a triangle between Anglesea, Torquay and Freshwater Creek.

In November 1998 he videotaped what he claims was a thylacine in East Gippsland. The grainy footage can be found on YouTube.

Mr Moss has a theory that tigers were introduced to Wilsons Promontory between 1910 and 1915.

During that time the park's committee of management had a policy of stocking the national park with endangered species including kangaroos, tiger quolls and birds.

"The timing is interesting because there are no records of tiger sightings until after 1912," Mr Moss said.

"The tiger still had a reputation as a stock killer so the last thing the committee would want to do is publicise it for fear farmers would go and shoot them, so that could be one reason why it was kept quiet."

Local wildlife biologist and thylacine guru Nick Mooney had heard the theory before and said it didn't wash.

"There is no evidence whatsoever beyond a vague conspiracy. There were some animals released at Wilsons Promontory but tigers were not on the list," he said.

He and other independent experts have examined Mr Moss's footage and believe it to be a mangy fox carrying a rabbit. Most mainland sightings could similarly be dismissed as stray dogs, foxes or even illusions, because the last fossil record of thylacines on mainland Australia date back to 1000 years before white settlement.

But Mr Mooney, who works in the Tasmanian Government's wildlife management branch, is by no means a sceptic about the tiger's continued existence: "I have always said it is possible -- not probable, but possible."

Thylacine DNA Restored To Life

Australian scientists say it may one day be possible to bring the dinosaur back to life, after a world-first experiment with DNA from the extinct Tasmanian tiger.

Injected DNA from preserved Tasmanian tiger specimens was injected and brought back to life in a mouse embryo in the nine-year experiment conducted by Melbourne University zoologists Andrew Pask and Marilyn Renfree.

In results published in the international scientific journal PLoS One, the experiment proved the tiger DNA was able to grow cartilage and bone in the mouse, showing the extinct gene could be brought back to life.

Dr Pask said the same technique could now be used with other extinct species such as the dinosaur, mammoth and neanderthal, all of which scientists had large amounts of DNA available.

And he said while the technique could recreate only a single extinct gene, with technology advancing all the time, it could one day be possible to bring whole creatures back to life.

"I have no doubt the whole creature could be brought back to life in the future," Dr Pask told AAP.

And he said creating combinations such as Pterodactyl wings on mice would also be possible.

"Yes it does, you could look at those combinations," he said.

In the world-first experiment, DNA was extracted from baby Tasmanian tigers which had been pickled in alcohol at Melbourne's Museum Victoria for a century.

The tigers were babies in their mothers' pouches when they were killed and preserved.

Tasmanian tigers have been extinct in the wild for about 100 years, with the last one of its kind dying in captivity in Hobart Zoo in 1936.

The experiment with their DNA was conducted in Houston with University of Texas molecular genetics professor Richard Behringer.

Professor Renfree said the study proved for the first time it was possible to resurrect the function of an extinct gene.

"This study has proved you can use DNA material from extinct animals and see what function they have," Prof Renfree said.

Prof Pask said as well as paving the way to recreate extinct species in the future, the research could also have potential bio-medical therapeutic outcomes.

"It gives us the ability to unleash the potential of extinct species," he said.

The experiment linked the tiger's DNA, the Col2a1 gene with a reporter gene, which showed the embryo's developing legs and arms.

The scientists said this showed the tiger gene would have a similar function in developing cartilage and bone development as an equivalent mouse gene.

The embryo was not developed into a live mouse, but Dr Pask said the technique could be taken further in the future, similar to the way DNA from still-surviving species was currently used.

"I think people have been introducing new life into mice and genetically modified organisms for a long, long time," he said.

"The only difference is this animal is extinct."

But the scientists stressed the ability to resurrect single genes of extinct species did not make the growing number of extinct species any less of a concern.

"Absolutely not," Prof Renfree said.

"The extinction of species is an enormous scientific concern, particularly in Australia where we have the worst record."

She said while the research allowed the function of individual genes from extinct species to be revealed, it was still a long way from being able to bring that species back to life.



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