News of a Tasmanian tiger sighting in Australia made the rounds about three weeks ago. This was big news, as Tasmanian tigers have supposedly been extinct since the 1930s.
The Tasmanian tiger, or thylacine, went extinct on the Australian mainland about 2000 years ago. The last thylacine died in Tasmania in the mid-1930s.
Professors at James Cook University had spoken to two reportedly reliable individuals who may have sighted a thylacine in Queensland, Australia. This particular sighting was intriguing enough to gain the attention of scientists. The descriptions the witnesses gave were apparently close to descriptions of thylacines.
There have been a lot of thylacine sightings over the past decades, though none have been confirmed. Now, a team of researchers at the University of California, Berkeley think that it's highly unlikely that Tasmanian Tigers still exist.
Of course, “highly unlikely” doesn't mean “impossible”. However, it's hard to be optimistic when the odds are one to 1.6 trillion.
How did these researchers come up with these numbers? Through mathematical modeling, of course.
There have been many confirmed and unconfirmed sightings of Tasmanian tigers from the beginning of the 20th century. The research team gathered data on these findings and analyzed them to figure out the likelihood that thylacines are still alive. The team considered two scenarios: the least optimistic and the most optimistic.
The least optimistic scenario considered only the confirmed sightings, while the most optimistic scenario considered the unconfirmed sightings as well. In the most optimistic scenario, remnants of thylacine populations would have held out only until the 1950s. From this assessment, the researchers calculated that there's only a one in 1.6 trillion chance that thylacines are still alive today.
The mathematical modeling the researchers used relied on recorded sightings. Thus, these numbers may not be applicable to the deeper wilderness. To remedy this, researchers at the University of Melbourne created their own model. This model takes data from more remote regions into account.
However, even this wider perspective still concludes that it's highly unlikely that Tasmanian tigers still exist. The University of Melbourne research found that if thylacines managed to survive beyond the 1930s, they would have died out in the early 1980s at the latest.
Thus, in both these mathematical models, there is a miniscule chance that thylacines would still be alive.
Though the researchers aren't optimistic that the search for Tasmanian tigers will be successful, they're not banking on the search's failure. If these mathematical models turn out to be wrong, the researchers will still consider it a win. “Like everybody else, I would be overjoyed,” says Brendan Wintle, one of the researchers from the University of Melbourne.
However, even Bill Laurance, the James Cook University professor who is leading the search for possible surviving Tasmanian tigers, isn't too optimistic. He admits that there's a very small chance that his team will find a live thylacine population, but it's worth checking out nonetheless.
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