Tasmanian Devil - Taxonomy

Taxonomy

Believing it to be a type of opossum, naturalist George Harris wrote the first published description of the Tasmanian devil in 1807, naming it Didelphis ursina, due to its bearlike characteristics such as the round ear. He had earlier made a presentation on the topic at the Zoological Society of London. However, that particular binomial name had been given to the common wombat (later reclassified as Vombatus ursinus) by George Shaw in 1800, and was hence unavailable. In 1838 a specimen was named Dasyurus laniarius by Richard Owen, but by 1877 he had relegated it to Sarcophilus. The modern Tasmanian devil was named Sarcophilus harrisii ("Harris's meat-lover") by French naturalist Pierre Boitard in 1841. A later revision of the devil's taxonomy, published in 1987, attempted to change the species name to Sarcophilus laniarius based on mainland fossil records of only a few animals. However, this was not accepted by the taxonomic community at large; the name S. harrisii has been retained and S. laniarius relegated to a fossil species. "Beelzebub's pup" was an early vernacular name given to it by the explorers of Tasmania, in reference to a religious deity who is a prince of hell and an assistant of Satan; the explorers first encountered the animal by hearing its far-reaching vocalisations at night. Related names that were used in the 19th century were Sarcophilus satanicus ("Satanic meatlover") and Diabolus ursinus ("ursine devil"), all due to early misconceptions of the devil as implacably vicious.

The Tasmanian devil (Sarcophilus harrisii) belongs to the family Dasyuridae. The genus Sarcophilus contains two other species, known only from Pleistocene fossils: S. laniarius and S. moomaensis. The relationships between the three species are not clear. Phylogenetic analysis shows that the devil is most closely related to quolls.

The roots of Australian marsupials are thought to trace back tens of millions of years to when much of the current southern hemisphere was part of the supercontinent of Gondwana; marsupials are believed to have originated in what is now South America and migrated across Antarctica, which had a temperate climate at the time. As soil degradation took hold, it is believed that the marsupials adapted to the more basic flora of Australia. According to Pemberton, the possible ancestors of the devil may have needed to climb trees to acquire food, leading to a growth in size and the hopping gait of many marsupials. He speculated that these adaptations may have caused the contemporary devil's peculiar gait. The specific lineage of the Tasmanian devil is theorised to have emerged during the Miocene, molecular evidence suggesting a split from the ancestors of quolls between 10 and 15 million years ago, when severe climate change came to bear in Australia, transforming the climate from warm and moist to an arid, dry ice age, resulting in mass extinctions. As most of their prey died of the cold, only a few carnivores survived, including the ancestors of the quoll and thylacine. It is speculated that the devil lineage may have arisen at this time to fill a niche in the ecosystem, as a scavenger that disposed of carrion left behind by the selective-eating thylacine. The extinct Glaucodon ballaratensis of the Pliocene age has been dubbed an intermediate species between the quoll and devil.

Fossil deposits in limestone caves at Naracoorte, South Australia, dating to the Miocene include specimens of S. laniarius, which were around 15% larger and 50% heavier than modern devils. Older specimens believed to be 50–70,000 years old were found in Darling Downs in Queensland and in Western Australia. It is not clear whether the modern devil evolved from S. laniarius, or whether they coexisted at the time. Richard Owen argued for the latter hypothesis in the 19th century, based on fossils found in 1877 in New South Wales. Large bones attributed to S. moornaensis have been found in New South Wales, and it has been conjectured that these two extinct larger species may have hunted and scavenged. It is known that there were several genera of thylacine millions of years ago, and that they ranged in size, the smaller being more reliant on foraging. As the devil and thylacine are similar, the extinction of the co-existing thylacine genera has been cited as evidence for an analogous history for the devils. It has been speculated that the smaller size of S. laniarius and S. moornaensis allowed them to adapt to the changing conditions more effectively and survive longer than the corresponding thylacines. As the extinction of these two species came at a similar time to human habitation of Australia, hunting by humans and land clearance have been mooted as possible causes. Critics of this theory point out that as indigenous Australians only developed boomerangs and spears for hunting around 10,000 years ago, a critical fall in numbers due to systematic hunting is unlikely. They also point out that caves inhabited by Aborigines have a low proportion of bones and rock paintings of devils, and suggest that this is an indication that it was not a large part of indigenous lifestyle. A scientific report in 1910 claimed that Aborigines preferred the meat of herbivores rather than carnivores. The other main theory for the extinction was that it was due to the climate change brought on by the most recent ice age.

While dingoes are seen as the main reason for the disappearance of devils from the mainland, another theory is that the increasing aridity of the mainland caused it, while the population in Tasmania has been largely unaffected as the climate remains cool and moist. According to this theory, the dingo was only a secondary cause.

As the devil is the thylacine's closest relative, there has been speculation that the thylacine could be revived by combining DNA from museum samples of thylacines with ova of the devil.

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