HOMO EXTINCTIONS

 Hello ladies and gents this is the Viking telling you that today we are talking about 

THE THYLACINES

By the beginning of the 20th century, the increasing rarity of thylacines led to increased demand for captive specimens by zoos around the world. Despite export of breeding pairs, these were unsuccessful and the last thylacine outside Australia died at London Zoo in 1931.

Extinction in the Australian mainland

Australia lost more than 90% of its larger terrestrial vertebrates by around 40 thousand years ago, with the notable exceptions of the kangaroo and the thylacine. A 2010 paper examining this issue showed that humans were likely to be one of the major factors in the extinction of many species in Australia although the authors of the research warned that one-factor explanations might be oversimplistic. The thylacine itself likely neared extinction throughout most of its range in mainland Australia by about 2,000 years ago.

However, reliable accounts of thylacine survival in South Australia (though confined to the "thinly settled districts" and Flinders Ranges) and New South Wales (Blue Mountains) exist from as late as the 1830s, from both indigenous and European sources.

A study proposes that the arrival of the dingoes may have led to the extinction of the Tasmanian devil, the thylacine, and the Tasmanian native hen in mainland Australia because the dingo might have competed with the thylacine and devil in preying on the native hen. However, the study also proposes that an increase in the human population that gathered pace around 4,000 years ago may have led to this.

However, a counter-argument is that the two species were not in direct competition with one another because the dingo primarily hunts during the day, whereas it is thought that the thylacine hunted mostly at night. 

Nonetheless, recent morphological examinations of dingo and thylacine skulls show that although the dingo had a weaker bite, its skull could resist greater stresses, allowing it to pull down larger prey than the thylacine. The thylacine was less versatile in its diet than the omnivorous dingo. Their ranges appear to have overlapped because thylacine subfossil remains have been discovered near those of dingoes. The adoption of the dingo as a hunting companion by the indigenous peoples would have put the thylacine under increased pressure.

Extinction in Tasmania

Although the thylacine was extinct on mainland Australia, it survived into the 1930s on the island state of Tasmania. At the time of the first European settlement, the heaviest distributions were in the northeast, northwest and north-midland regions of the state. They were rarely sighted during this time but slowly began to be credited with numerous attacks on sheep. This led to the establishment of bounty schemes in an attempt to control their numbers. 

The Van Diemen's Land Company introduced bounties on the thylacine from as early as 1830, and between 1888 and 1909 the Tasmanian government paid £1 per head for dead adult thylacines and ten shillings for pups. In all, they paid out 2,184 bounties, but it is thought that many more thylacines were killed than were claimed for. Its extinction is popularly attributed to these relentless efforts by farmers and bounty hunters.

However, it is likely that multiple factors led to its decline and eventual extinction, including competition with wild dogs introduced by European settlers, erosion of its habitat, the concurrent extinction of prey species, and a distemper-like disease that affected many captive specimens at the time.

 A study from 2012 also found that were it not for an epidemiological influence, the extinction of thylacine would have been at best prevented, at worst postponed. "The chance of saving the species, through changing public opinion, and the re-establishment of captive breeding, could have been possible. But the marsupi-carnivore disease, with its dramatic effect on individual thylacine longevity and juvenile mortality, came far too soon, and spread far too quickly."

Whatever the reason, the animal had become extremely rare in the wild by the late 1920s. Despite the fact that the thylacine was believed by many to be responsible for attacks on sheep, in 1928 the Tasmanian Advisory Committee for Native Fauna recommended a reserve similar to the Savage River National Park to protect any remaining thylacines, with potential sites of suitable habitat including the Arthur-Pieman area of western Tasmania.

The last known thylacine to be killed in the wild was shot in 1930 by Wilf Batty, a farmer from Mawbanna in the state's northwest. The animal, believed to have been a male, had been seen around Batty's house for several weeks.

Work in 2012 examined the relationship of the genetic diversity of the thylacines before their extinction. The results indicated that the last of the thylacines in Australia, on top of the threats from dingoes, had limited genetic diversity, due to their complete geographic isolation from mainland Australia. Further investigations in 2017 showed evidence that this decline in genetic diversity started long before the arrival of humans in Australia, possibly starting as early as 70–120 thousand years ago

And as always have a chilled day from the Viking