The thylacine ( ; Thylacinus cynocephalus), also commonly known as the Tasmanian tiger, Tasmanian wolf or marsupial wolf, is an extinct species of carnivorous marsupial formerly native to the Australian mainland, Tasmania and New Guinea. It became extinct on mainland Australia and New Guinea approximately 3,600–3,200 years ago, possibly following the arrival of the dingo, which was introduced to Australia around the same period but never reached Tasmania. Prior to European settlement, the species remained widespread in Tasmania, where its population was estimated to number several thousand individuals. During the 19th century, the species was increasingly persecuted because of its perceived threat to livestock, with government-sponsored bounty schemes encouraging its extermination. The last known individual died at Hobart Zoo in Tasmania on 7 September 1936.
The thylacine was known as the Tasmanian tiger because of the dark transverse stripes that radiated from the top of its back, and it was called the Tasmanian wolf because it resembled a medium- to large-sized canid. The name thylacine is derived from meaning 'pouch' and -ine meaning 'pertaining to', and refers to the marsupial pouch. Both sexes had a pouch. The females used theirs for rearing young, and the males used theirs as a protective sheath, covering the external reproductive organs. The animal had a stiff tail and could open its jaws to an unusual extent. Recent studies and anecdotal evidence on its predatory behaviour suggest that the thylacine was a solitary ambush predator specialised in hunting small- to medium-sized prey. Accounts suggest that, in the wild, it fed on small birds and mammals. It was the only member of the genus Thylacinus and family Thylacinidae to have survived until modern times. Its closest living relatives are the other members of Dasyuromorphia, including the Tasmanian devil, from which it is estimated to have split 42–36 million years ago.
Intensive hunting on Tasmania is generally blamed for its extinction, but other contributing factors were disease, the introduction of and competition with dingoes, human encroachment into its habitat and climate change. Since extinction there have been numerous searches and reported sightings of live animals, none of which have been confirmed.
The thylacine has been used extensively as a symbol of Tasmania. The animal is featured on the official coat of arms of Tasmania. Since 1996, National Threatened Species Day has been commemorated in Australia on 7 September, the date on which the last known thylacine died in 1936. Universities, museums and other institutions across the world research the animal. Its whole genome sequence has been mapped, and there are efforts to clone and bring it back to life.
Discovery, taxonomy and etymology Numerous examples of thylacine engravings and rock art have been found, dating back to at least 1000 BC. Petroglyph images of the thylacine can be found at the Dampier Rock Art Precinct, on the Burrup Peninsula in Western Australia.
By the time the first European explorers arrived, the animal was already extinct in mainland Australia and New Guinea and rare in Tasmania. Europeans may have encountered it in Tasmania as far back as 1642, when Abel Tasman first arrived in Tasmania. His shore party reported seeing the footprints of "wild beasts having claws like a Tyger". Quoted in Marc-Joseph Marion du Fresne, arriving with the Mascarin in 1772, reported seeing a "tiger cat".Roth, H. L. (1891) "Crozet's Voyage to Tasmania, New Zealand, etc. ... 1771–1772.". London. Truslove and Shirley. Quoted in The first definitive encounter was by French explorers on 13 May 1792, as noted by the naturalist Jacques Labillardière, in his journal from the expedition led by d'Entrecasteaux. In 1805, William Paterson, the Lieutenant Governor of Tasmania, sent a detailed description for publication in the Sydney Gazette. He also sent a description of the thylacine in a letter to Joseph Banks, dated 30 March 1805.Description of a Tasmanian Tiger Received by Banks from William Paterson, 30 March 1805. (n.d.). Sir Joseph Banks Papers, State Library of New South Wales, SAFE/Banks Papers/Series 27.33 The first detailed scientific description was made by Tasmania's Deputy Surveyor-General, George Harris, in 1808, five years after first European settlement of the island. Harris originally placed the thylacine in the genus Didelphis, which had been created by Linnaeus for the American opossums, describing it as Didelphis cynocephala, the "dog-headed opossum". Recognition that the Australian marsupials were fundamentally different from the known mammal genera led to the establishment of the modern classification scheme, and in 1796, Geoffroy Saint-Hilaire created the genus Dasyurus, where he placed the thylacine in 1810. To maintain gender agreement with the genus name, the species name was altered to cynocephalus. In 1824, it was separated out into its own genus, Thylacinus, by Temminck. The common name "thylacine" derives directly from the genus name, originally from the Greek (), meaning "pouch" or "sack" and ine meaning "pertaining to". The name is pronounced or .
The Australian National Dictionary recognises 11 different informal common names that have been used to refer to Thylacinus cynocephalus, most of which have now fallen into disuse. In the 1800s they were widely known as zebra wolves, zebra opossums or dog-headed opossums; the latter a direct translation of the obsolete binomial Didelphis cynocephalus. They were also referred to as hyena opossums or simply hyenas in parts of Tasmania. These names fell out of use during the early 20th century in favour of the contemporary terms Tasmanian tiger, Tasmanian wolf or marsupial wolf, referencing the animal's striped patterning and wolf-like appearance respectively. The disparity in English common names has been attributed to the animal's unique combination of features. Various Aboriginal Tasmanian names for the thylacine have been recorded, such as coorinna, kanunnah, cab-berr-one-nen-er, loarinna, laoonana, can-nen-ner and lagunta, while kaparunina is used in Palawa kani.
Evolutionary history The earliest records of the modern thylacine are from the Early Pleistocene, with the oldest known fossil record in southeastern Australia from the Calabrian age around 1.77–0.78 million years ago. Specimens from the Pliocene-aged Chinchilla Fauna, described as Thylacinus rostralis by Charles De Vis in 1894, have in the past been suggested to represent Thylacinus cynocephalus, but have been shown to either have been curatorial errors, or ambiguous in their specific attribution.Mackness, B. S., et al. "Confirmation of Thylacinus from the Pliocene Chinchilla Local Fauna". Australian Mammalogy. 24.2 (2002): 237–242. The family Thylacinidae includes at least 12 species in eight genera. Thylacinids are estimated to have split from other members of Dasyuromorphia around 42–36 million years ago. The earliest representative of the family is Badjcinus turnbulli from the Late Oligocene of Riversleigh in Queensland, around 25 million years ago. Early thylacinids were quoll-sized, well under . It probably ate insects and small reptiles and mammals, although signs of an increasingly-carnivorous diet can be seen as early as the early Miocene in Wabulacinus. Members of the genus Thylacinus are notable for a dramatic increase in both the expression of carnivorous dental traits and in size, with the largest species, Thylacinus potens and Thylacinus megiriani, both approaching the size of a wolf. In late Pleistocene and early Holocene times, the modern thylacine was widespread (although never numerous) throughout Australia and New Guinea. A classic example of convergent evolution, the thylacine showed many similarities to the members of the dog family, Canidae, of the Northern Hemisphere: sharp teeth, powerful jaws, raised heels, and the same general body form. Since the thylacine filled the same ecological niche in Australia and New Guinea as canids did elsewhere, it developed many of the same features. Despite this, as a marsupial, it is unrelated to any of the Northern Hemisphere placental mammal predators.
Thylacinidae, including the thylacine, are the earliest diverging lineage of Dasyuromorphia, which also includes numbats, dunnarts, and Dasyuridae (which includes wambengers, quolls, and the Tasmanian devil, among numerous others). The cladogram below follows the results of genetic studies:Phylogeny of Thylacinidae after Rovinsky et al. (2019)
Description
Descriptions of the thylacine come from preserved specimens, fossil records, skins and skeletal remains, and black and white photographs and film of the animal both in captivity and from the field. The thylacine resembled a large, short-haired dog with a stiff tail which smoothly extended from the body in a way similar to that of a kangaroo. The mature thylacine measured about in shoulder height and in body length, excluding the tail which measured around . Because the recorded body mass estimates are scant, it has been suggested that they may have weighed anywhere from , but a 2020 study that examined 93 adult specimens, with 40 of the specimens' sexes being known, argued that their average body mass would be with a range of based on volumetric analysis. There was slight sexual dimorphism, with the males being larger than females on average. Males weighed on average , and females on average weighed . The skull is noted to be highly convergent on those of canids, most closely resembling that of the red fox.
Thylacines, uniquely for marsupials, had largely cartilaginous epipubic bones with a highly reduced osseous element.Ronald M. Nowak, Walker's Marsupials of the World, JHU Press, 12 September 2005 This was once considered a synapomorphy with sparassodonts,Marshall, L. Evolution of the Borhyaenidae, extinct South American predaceous marsupials. Berkeley: University of California Press, 1978. though it is now thought that both groups reduced their epipubics independently. Its yellow-brown coat featured 15 to 20 distinctive dark stripes across its back, rump and the base of its tail, which earned the animal the nickname "tiger". The stripes were more pronounced in younger specimens, fading as the animal got older. One of the stripes extended down the outside of the rear thigh. Its body hair was dense and soft, up to in length. Colouration varied from light fawn to a dark brown; the belly was cream-coloured.
Its rounded, erect ears were about long and covered with short fur. The early scientific studies suggested it possessed an acute sense of smell which enabled it to track prey, but analysis of its brain structure revealed that its olfactory bulbs were not well developed. It is likely to have relied on sight and sound when hunting instead. In 2017, Berns and Ashwell published comparative cortical maps of thylacine and Tasmanian devil brains, showing that the thylacine had a larger, more modularised basal ganglion. The authors associated these differences with the thylacine's more predatory lifestyle. Analysis of the forebrain published in 2023 suggested that it was similar in morphology to other dasyuromorph marsupials and dissimilar to that of canids.