Editing Tasmanian devil (section)

==Taxonomy==
Believing it to be a type of [[Ameridelphia|opossum]], naturalist [[George Prideaux Robert Harris|George Harris]] wrote the first published description of the Tasmanian devil in 1807, naming it ''Didelphis ursina'',<ref name=Harris1807/> due to its bearlike characteristics such as the round ear.<ref>Owen and Pemberton, p. 79.</ref> He had earlier made a presentation on the topic at the [[Zoological Society of London]].<ref name="Owen and Pemberton-8"/> However, that particular binomial name had been given to the [[common wombat]] (later reclassified as ''Vombatus ursinus'') by [[George Shaw (biologist)|George Shaw]] in 1800, and was hence unavailable.<ref name=MSW3>{{MSW3 Dasyuromorphia|id=10800047|page=28}}</ref> In 1838, a specimen was named ''Dasyurus laniarius'' by [[Richard Owen]],<ref name="Mitchell-1839">{{cite book |last=Mitchell |first=Thomas |author-link=Thomas Mitchell (explorer) |title=Three Expeditions into the Interior, Volume II |publisher=T. & W. Boone |year=1839}} [http://gutenberg.net.au/ebooks/e00036.html Online] at Project Gutenberg Australia.</ref> but by 1877 he had relegated it to ''Sarcophilus''. The modern Tasmanian devil was named ''Sarcophilus harrisii'' ("Harris's flesh-lover") by French naturalist [[Pierre Boitard]] in 1841.<ref>{{cite journal|last1=Stephenson|first1=N. G.|title=Growth gradients among fossil monotremes and marsupials {{!}} The Palaeontological Association|journal=Palaeontology|date=1963|volume=6|issue=4|pages=615–624|url=http://www.palass.org/publications/palaeontology-journal/archive/6/4/article_pp615-624|language=en}}</ref>

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.<ref name=Werdelin1987/> However, this was not accepted by the taxonomic community at large; the name ''S.&nbsp;harrisii'' has been retained and ''S.&nbsp;laniarius'' relegated to a fossil species.<ref name=MSW3/> "[[Beelzebub]]'s pup" was an early vernacular name given to it by the explorers of Tasmania, in reference to a religious figure who is a prince of hell and an assistant of [[Satan]];<ref name="Owen and Pemberton-8">Owen and Pemberton, p. 8.</ref> the explorers first encountered the animal by hearing its far-reaching vocalisations at night.<ref>Owen and Pemberton, p. 7.</ref> Related names that were used in the 19th century were ''Sarcophilus satanicus'' ("Satanic flesh-lover") and ''Diabolus ursinus'' ("bear devil"), all due to early misconceptions of the species as implacably vicious.<ref name="Owen and Pemberton-8"/> The Tasmanian devil (''Sarcophilus harrisii'') belongs to the family [[Dasyuridae]]. The genus ''Sarcophilus'' contains two other species, known only from [[Pleistocene]] fossils: ''S.&nbsp;laniarius'' and ''S.&nbsp;moomaensis''. [[Phylogenetics|Phylogenetic]] analysis shows that the Tasmanian devil is most closely related to [[quoll]]s.<ref name=Krajewski1992/>

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.<ref name="Owen and Pemberton-34">Owen and Pemberton, p. 34.</ref> 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,<ref name=PwP16>{{cite book|author1=Krajewski, Carey |author2=Westerman, Michael |year=2003|title=Predators with Pouches: The Biology of Carnivorous Marsupials|chapter=Molecular Systematics of Dasyuromorpha|page=16|editor1=Jones, Menna |editor2=Dickman, Chris |editor3=Archer, Mike |publisher=CSIRO Publishing|location=Collingwood, Victoria|isbn=0-643-06634-9}}</ref> 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.<ref name="Owen and Pemberton-34"/> 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.<ref name="Owen and Pemberton-34"/> The extinct ''[[Glaucodon]] ballaratensis'' of the [[Pliocene]] age has been dubbed an intermediate species between the quoll and devil.<ref>{{cite book|last1=Long|first1=John A.|author-link1=John A. Long |last2=Archer|first2=Michael|author-link2=Mike Archer (paleontologist) |last3=Flannery|first3=Timothy |last4=Hand|first4=Suzanne |title=Prehistoric Mammals of Australia and New Guinea: One Hundred Million Years of Evolution|url=https://books.google.com/books?id=92yhnRHdxSoC&pg=PA55|year=2002|publisher=University of New South Wales Press|isbn=978-0-8018-7223-5|page=55}}</ref> [[File:Jenolan Caves Tasmanian Devil jaw.jpg|thumb|right|A jawbone found in the mainland [[Jenolan Caves]]]] Fossil deposits in limestone caves at [[Naracoorte, South Australia]], dating to the [[Miocene]] include specimens of ''S.&nbsp;laniarius'', which were around 15% larger and 50% heavier than modern devils.<ref>Owen and Pemberton, p. 35.</ref> Older specimens believed to be 50–70,000 years old were found in [[Darling Downs]] in [[Queensland]] and in [[Western Australia]].<ref name="Owen and Pemberton-36"/> It is not clear whether the modern devil evolved from ''S.&nbsp;laniarius'', or whether they coexisted at the time.<ref name="Owen and Pemberton-36">Owen and Pemberton, p. 36.</ref> Richard Owen argued for the latter hypothesis in the 19th century, based on fossils found in 1877 in [[New South Wales]].<ref name="Owen and Pemberton-36"/> Large bones attributed to ''S.&nbsp;moornaensis'' have been found in New South Wales,<ref name="Owen and Pemberton-36"/> and it has been conjectured that these two extinct larger species may have hunted and scavenged.<ref name="Owen and Pemberton-36"/> It is known that there were several [[genus|genera]] of thylacine millions of years ago, and that they ranged in size, the smaller being more reliant on foraging.<ref>Owen and Pemberton, p. 37.</ref> 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.<ref name="Owen and Pemberton-38">Owen and Pemberton, p. 38.</ref> It has been speculated that the smaller size of ''S.&nbsp;laniarius'' and ''S.&nbsp;moornaensis'' allowed them to adapt to the changing conditions more effectively and survive longer than the corresponding thylacines.<ref name="Owen and Pemberton-38"/> 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.<ref name="Owen and Pemberton-39">Owen and Pemberton, p. 39.</ref> Critics of this theory point out that as indigenous Australians only developed [[boomerang]]s 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.<ref>Owen and Pemberton, pp. 40–42.</ref> The other main theory for the extinction was that it was due to the climate change brought on by the most recent ice age.<ref name="Owen and Pemberton-39"/>

===Genetics===
[[File:Karyotype of Tasmanian devil (Sarcophilus Harrisii).png|right|thumb|[[Karyotype]] of male Tasmanian devil]]
The Tasmanian devil's [[genome]] was sequenced in 2010 by the [[Wellcome Trust Sanger Institute]].<ref>{{cite press release |url=http://www.sanger.ac.uk/news/view/2010-09-16-completed-genome-is-first-step-to-tackling-tasmanian-devil-facial-tumours |title=Completed genome is first step to tackling Tasmanian devil facial tumours|date=16 September 2010|access-date=10 December 2015|publisher=[[Wellcome Trust Sanger Institute]]}}</ref> Like all dasyurids, the devil has 14 chromosomes.<ref>Tyndale-Biscoe, p. 143.</ref> Devils have a low [[genetic diversity]] compared to other Australian marsupials and placental carnivores; this is consistent with a [[founder effect]] as allelic size ranges were low and nearly continuous throughout all subpopulations measured. Allelic diversity was measured at 2.7–3.3 in the subpopulations sampled, and [[heterozygosity]] was in the range 0.386–0.467.<ref name=mj04/> According to a study by Menna Jones, "[[gene flow]] appears extensive up to {{cvt|50|km}}", meaning a high assignment rate to source or close neighbour populations "in agreement with movement data. At larger scales ({{cvt|150|–|250|km|disp=or}}), gene flow is reduced but there is no evidence for isolation by distance".<ref name=mj04/> [[Foster's rule|Island effects]] may also have contributed to their low genetic diversity. Periods of low population density may also have created moderate [[population bottleneck]]s, reducing genetic diversity.<ref name=mj04/> Low genetic diversity is thought to have been a feature in the Tasmanian devil population since the mid-[[Holocene]].<ref name="morris&austin2012"/> Outbreaks of [[devil facial tumour disease]] (DFTD) cause an increase in [[inbreeding]].<ref name=LachishMiller2010/> A sub-population of devils in the north-west of the state is genetically distinct from other devils,<ref name=fed>{{cite web|url=http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=299|title=''Sarcophilus harrisii'' – Tasmanian Devil |work=Species Profile and Threats Database |publisher=Department of Sustainability, Environment, Water, Population and Communities|access-date=30 September 2010}}</ref> but there is some exchange between the two groups.<ref name=draft>{{cite web |year=2010 |url=http://dpipwe.tas.gov.au/Documents/Draft-Tasmanian-Devil-Recovery-Plan.pdf |title=Draft Recovery Plan for the Tasmanian devil (''Sarcophilus harrisii'')|publisher=Department of Primary Industries, Parks, Water and Environment |location=Hobart |access-date=3 September 2015}}</ref>

One strand conformation polymorphism analysis (OSCP) on the [[major histocompatibility complex]] (MHC) [[MHC class I|class I]] domain taken from various locations across Tasmania showed 25 different types, and showed a different pattern of MHC types in north-western Tasmania to eastern Tasmania. Those devils in the east of the state have less MHC diversity; 30% are of the same type as the tumour (type 1), and 24% are of type A.<ref name=sid/> Seven of every ten devils in the east are of type A, D, G or 1, which are linked to DFTD; whereas only 55% of the western devils fall into these MHC categories. Of the 25 MHC types, 40% are exclusive to the western devils. Although the north-west population is less genetically diverse overall, it has higher MHC gene diversity, which allows them to mount an immune response to DFTD. According to this research, mixing the devils may increase the chance of disease.<ref name=sid/><!-- cites both previous --> Of the fifteen different regions in Tasmania surveyed in this research, six were in the eastern half of the island. In the eastern half, Epping Forest had only two different types, 75% being type O. In the Buckland-Nugent area, only three types were present, and there were an average of 5.33 different types per location. In contrast, in the west, Cape Sorell yielded three types, and Togari North-Christmas Hills yielded six, but the other seven sites all had at least eight MHC types, and West Pencil Pine had 15 types. There was an average of 10.11 MHC types per site in the west.<ref name=sid/> Recent research has suggested that the wild population of devils are rapidly evolving a resistance to DFTD.<ref>{{cite journal|last1=Epstein|first1=Brendan|last2=Jones|first2=Menna|last3=Hamede|first3=Rodrigo|last4=Hendricks|first4=Sarah|last5=McCallum|first5=Hamish|last6=Murchison|first6=Elizabeth P.|last7=Schönfeld|first7=Barbara|last8=Wiench|first8=Cody|last9=Hohenlohe|first9=Paul|last10=Storfer|first10=Andrew|title=Rapid evolutionary response to a transmissible cancer in Tasmanian devils|journal=[[Nature Communications]]|date=30 August 2016|volume=7|pages=12684|doi=10.1038/ncomms12684|pmid=27575253|pmc=5013612|bibcode=2016NatCo...712684E}}</ref>