Wednesday marks the 80th anniversary of the extinction of the thylacine, also known as the Tasmanian tiger. Or, at least, that’s the date that has been agreed upon in official sources.

The thylacine was a street-dog-size animal with a stiff, catlike tail, a pouch on its belly and stripes on its back and rear that resembled a tiger’s. But it was a marsupial, one native to Australia, Tasmania and New Guinea. And like other creatures before and since, it probably fell victim to hunting, as well as invasive species and habitat destruction.

I took up the issue of dating the thylacine’s extinction in my recently published article “Presence of absence, absence of presence, and extinction narratives” in Nature, Temporality and Environmental Management: Scandinavian and Australian Perspectives on Landscapes and Peoples. The question is whether the absence of evidence of live thylacines should be interpreted as the absence of thylacines. This proves a more challenging question to answer than you may think.

The last confirmed thylacine died Sept. 7, 1936, in the Beaumaris Zoo in Hobart, Tasmania. Two years before, the Australasian newspaper of Melbourne had published photos of that particular thylacine, named Benjamin, for a report about the zoo. It was the last time a live thylacine was captured on film.

But the decision that those photos represent “the last” thylacine came in retrospect.

In 1936, most people accepted that thylacine numbers had been radically declining, but few thought the animal was extinct. The Tasmanian Animals and Birds’ Protection Board (later to become the National Park Service) organized an expedition to count thylacines in the mountainous region in 1938 and published a report on that search in 1939. The report included photographs of team members making plaster of Paris casts of thylacine footprints, as well as recording other evidence of thylacine presence. No thylacines themselves, however, were spotted.

This did not deter the expedition leader, Michael Sharland, from believing that the species still survived:

“It must be emphasized, however, that its failure to reveal itself more frequently is not necessarily indicative of approaching extinction,” he wrote. “Great areas of this game country are devoid of human inhabitants, while others are only sparsely inhabited.”

The sentiment that thylacines were still out there somewhere — we were just looking in the wrong places — continued long after this. In the article, I wrote about some of the many searches to find thylacines, including one in 1980 organized by the World Wildlife Fund and another in 1984, which was prompted by media magnate Ted Turner’s offer of $100,000 for a proven thylacine sighting. None of these expeditions turned up what was considered scientifically credible evidence of the thylacine’s continued existence. Yet sightings continued to be regularly reported in local newspapers — and still are. The failure to have scientific confirmation has not deterred the belief of many that the thylacine is out there.

The thylacine was officially declared extinct by the International Union for the Conservation of Nature — which is holding its annual congress in Hawaii right now — in 1982 and by the Tasmanian government in 1986. In these declarations, the absence of presence was declared as a presence of absence. In 1996, Australia established National Threatened Species Day on Sept. 7 to commemorate the 60th anniversary of the death of the Hobart thylacine.

This made the narrative of extinction official: Sept. 7, 1936, was the end of the thylacine.

The importance of the death of the thylacine in the Hobart Zoo was recognized only in retrospect. It was only when no more could be found after years and years of looking that the date of the tiger’s extinction was set.

So I am left wondering how someone 80 years from now will look back on the extinctions going on all around us in 2016. How many things that we do not have on our lists now will be on the lists then with dates of extinction before 2016? Will people still remember the thylacine at its 160th extinction anniversary — or will it be reduced in importance as just one of many recent extinctions?

Jorgensen is a historian at Lulea University of Technology in Sweden, where she focuses on human-animal relations, the urban environment and environmental policymaking. This article is adapted from a post on a blog she writes about her research on the return of native Nordic fauna.

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