Editing Thylacine (section)

== Ecology and behaviour ==
[[File:Thylacine cubs.jpg|thumb|right|Thylacine family at [[Beaumaris Zoo]] in [[Hobart]], 1909]]
[[File:Thylacines.jpg|thumb|right|Thylacine family at Beaumaris Zoo in Hobart, 1910]]

===Reproduction===
There is evidence for at least some year-round breeding (cull records show joeys discovered in the pouch at all times of the year), although the peak breeding season was in winter and spring.<ref name="ABRS" /> They would produce up to four joeys per litter (typically two or three), carrying the young in a pouch for up to three months and protecting them until they were at least half adult size. Early pouch young were hairless and blind, but they had their eyes open and were fully furred by the time they left the pouch.<ref>Newton, Axel H.; Spoutil, Frantisek; Prochazka, Jan; Black, Jay R.; Medlock, Kathryn; Paddle, Robert N.; Knitlova, Marketa; Hipsley, Christy A.; Pask, Andrew J. (21 February 2018). "Letting the 'cat' out of the bag: pouch young development of the extinct Tasmanian tiger revealed by X-ray computed tomography". Royal Society Open Science. 5 (2): 171914. Bibcode:2018RSOS....571914N. doi:10.1098/rsos.171914. PMC 5830782. PMID 29515893.</ref> The young also had their own pouches that were not visible until they were 9.5 weeks old.<ref name="ABRS" /> After leaving the pouch, and until they were developed enough to assist, the juveniles would remain in the lair while their mother hunted.<ref name="P60">[[#Paddle|Paddle (2000)]], p. 60.</ref> Thylacines only once bred successfully in captivity, in [[Melbourne Zoo]] in 1899.<ref name="P228231">[[#Paddle|Paddle (2000)]], pp. 228–231.</ref> Their life expectancy in the wild is estimated to have been 5 to 7 years, although captive specimens survived up to 9 years.<ref name="tasparks" />
[[File:ThylacineFetus.jpg|thumb|266x266px|A thylacine [[fetus]] at the [[Australian Museum]]]]
In 2018, Newton et al. collected and CT-scanned all known preserved thylacine pouch young specimens to digitally reconstruct their development throughout their entire window of growth in their mother's pouch. This study revealed new information on the biology of the thylacine, including the growth of its limbs and when it developed its 'dog-like' appearance. It was found that two of the thylacine young in the Tasmanian Museum and Art Gallery (TMAG) were misidentified and of another species, reducing the number of known pouch young specimens to 11 worldwide.<ref name="newton">{{cite journal|last1=Newton|first1=Axel H.|last2=Spoutil|first2=Frantisek|last3=Prochazka|first3=Jan|last4=Black|first4=Jay R.|last5=Medlock|first5=Kathryn|last6=Paddle|first6=Robert N.|last7=Knitlova|first7=Marketa|last8=Hipsley|first8=Christy A.|last9=Pask|first9=Andrew J.|title=Letting the 'cat' out of the bag: pouch young development of the extinct Tasmanian tiger revealed by X-ray computed tomography|journal=Royal Society Open Science|date=21 February 2018|volume=5|issue=2|page=171914|doi=10.1098/rsos.171914|pmid=29515893|pmc=5830782|bibcode=2018RSOS....571914N}}</ref> One of four specimens kept at Museum Victoria has been serially sectioned, allowing an in-depth investigation of its internal tissues and providing some insights into thylacine pouch young development, biology, immunology and ecology.<ref name="Old">{{cite journal|last=Old|first=Julie M.|title=Immunological Insights into the Life and Times of the Extinct Tasmanian Tiger (''Thylacinus cynocephalus'')|journal=PLOS ONE|date=2015|volume=10 |issue=12 |pages=e0144091 |doi=10.1371/journal.pone.0144091|pmid=26655868 |pmc=4684372 |bibcode=2015PLoSO..1044091O |doi-access=free }}</ref>

=== Feeding and diet ===
[[File:Animal life in the sea and on the land (1887) (14780637625).jpg|thumb|left|1887 illustration of an emu being chased by two thylacines]]
The thylacine was an [[apex predator]],<ref name="Paddle">[[#Paddle|Paddle (2000)]]</ref> though exactly how large its prey animals could be is disputed. It was a [[Nocturnal animal|nocturnal]] and [[crepuscular]] hunter, spending the daylight hours in small caves or hollow tree trunks in a nest of twigs, bark, or fern fronds. It tended to retreat to the hills and forest for shelter during the day and hunted in the open heath at night. Early observers noted that the animal was typically shy and secretive, with awareness of the presence of humans and generally avoiding contact, although it occasionally showed inquisitive traits.<ref name="sight">{{Cite journal | last = Heberle | first = G. | year = 1977 | journal = [[The Sunday Telegraph (Sydney)|Sunday Telegraph]] | page = 46 | title = Reports of alleged thylacine sightings in Western Australia | url = http://freepages.genealogy.rootsweb.ancestry.com/~gregheberle/AdobePDF/Thylacine/ThylacinePaper2004-P1-5.pdf | format = w | access-date = 5 February 2012 | archive-url = https://web.archive.org/web/20130521142704/http://freepages.genealogy.rootsweb.ancestry.com/~gregheberle/AdobePDF/Thylacine/ThylacinePaper2004-P1-5.pdf | archive-date = 21 May 2013 | url-status = dead | df = dmy-all }}</ref> At the time, much stigma existed in regard to its "fierce" nature; this is likely to be due to its perceived threat to agriculture.<ref>[http://www.australiangeographic.com.au/journal/largest-private-collection-of-tasmanian-tigers-on-display.htm/ Tasmanian tigers brought to life] {{webarchive|url=https://web.archive.org/web/20110312203711/http://www.australiangeographic.com.au/journal/largest-private-collection-of-tasmanian-tigers-on-display.htm |date=12 March 2011 }}, Australian Geographic, 24 February 2011.</ref>

Historical accounts suggest that in the wild, the thylacine preyed on small mammals and birds, with waterbirds being the most commonly recorded bird prey, with historical accounts of thylacines predating on [[Pacific black duck|black ducks]] and [[Chestnut teal|teals]] with [[Eurasian coot|coots]], [[Tasmanian nativehen|Tasmanian nativehens]], [[Western swamphen|swamphens]], herons (''[[Ardea (bird)|Ardea]]'') and [[Black swan|black swans]] also being likely items of prey. The thylacine may also have preyed upon the now extinct [[Tasmanian emu]].<ref name="P812">[[Thylacine#Paddle|Paddle (2000)]], pp. 81.</ref> The most commonly recorded mammalian prey was the [[red-necked wallaby]], with other recorded prey including the [[Tasmanian pademelon]] and the [[short-beaked echidna]]. Other probable native mammalian prey includes other marsupials like [[Bandicoot|bandicoots]] and [[Brushtail possum|brushtail possums]], as well as native rodents like [[Rakali|water rats]].<ref>[[Thylacine#Paddle|Paddle (2000)]], pp. 79–80.</ref> Following their introduction to Tasmania, European rabbits rapidly multiplied and became abundant across the island, with a number of accounts reporting the predation of rabbits by thylacines.<ref>[[Thylacine#Paddle|Paddle (2000)]], p 84.</ref> Some accounts also suggest that the thylacine may have preyed on lizards, frogs and fish.<ref>[[Thylacine#Paddle|Paddle (2000)]], p 82.</ref> 

European settlers believed the thylacine to prey regularly upon farmers' sheep and poultry.{{efn|Based on the lack of reliable first hand accounts, Robert Paddle argues that the predation on sheep and poultry may have been exaggerated, suggesting the thylacine was used as a convenient scapegoat for the mismanagement of the sheep farms, and the image of it as a poultry killer impressed on the public consciousness by a striking photo taken by Henry Burrell in 1921.<ref name="P79">[[#Paddle|Paddle (2000)]], pp. 79–138.</ref>}} However, analysis by Robert Paddle suggests that there is little evidence that thylacines were significant predators of sheep or poultry (though some accounts suggest that they may have attacked them on occasion), with many sheep deaths likely caused by feral dog attacks instead.<ref>[[Thylacine#Paddle|Paddle (2000)]], pp. 83-138.</ref> Throughout the 20th century, the thylacine was often characterised as primarily a blood drinker; according to Robert Paddle, the story's popularity seems to have originated from a single second-hand account heard by Geoffrey Smith (1881–1916)<ref>Smith, Geoffrey Watkins (1909) [https://www.worldcat.org/oclc/504699783 "A Naturalist in Tasmania."] {{Webarchive|url= https://web.archive.org/web/20140910195542/http://www.worldcat.org/title/naturalist-in-tasmania/oclc/504699783 |date=10 September 2014 }}. Clarendon Press: Oxford.</ref><ref>[http://www.winchestercollegeatwar.com/archive/geoffrey-watkins-smith/ "Smith, Geoffrey Watkins"] {{Webarchive|url= https://web.archive.org/web/20141103220934/http://www.winchestercollegeatwar.com/archive/geoffrey-watkins-smith/ |date=3 November 2014 }}. ''winchestercollegeatwar.com''.</ref> in a shepherd's hut.<ref name="P2935">[[#Paddle|Paddle (2000)]], pp. 29–35.</ref>
[[File:Beutelwolfskelett brehm.png|thumb|Analysis of the skeleton suggests that, when hunting, the thylacine relied on stamina rather than speed in the chase.]]

Recent studies suggest that the thylacine was probably not suited for hunting large prey. A 2007 study argued that, while it could open its jaws wide like modern mammalian predators that consume large prey, the canine of the thylacine was not suited for slashing bites like that of large canids, indicating, based on the assumption that the bite was largely derived by its skull, that it hunted small to medium-sized prey as a solitary hunter.<ref name=W07/> A 2011 study by the [[University of New South Wales]] using advanced computer modelling indicated that the thylacine had surprisingly feeble jaws; animals usually take prey close to their own body size, but an adult thylacine of around {{cvt|30|kg}} was found to be incapable of handling prey much larger than {{cvt|5|kg}}, suggesting that the thylacine only ate smaller animals such as bandicoots, pademelons and possums, and that it may have directly competed with the [[Tasmanian devil]] and the [[tiger quoll]].<ref name="autogenerated1"/><ref name=A14/> Another study in 2020 produced similar results, after estimating the average body mass of thylacine as about {{cvt|16.7|kg}} rather than {{cvt|30|kg}}, suggesting that the animal did indeed hunt much smaller prey.<ref name="REMA"/> The cranial and facial morphology also indicate that the thylacine would have hunted prey less than 45% of its own body mass, consistent with modern carnivores weighing under {{cvt|21|kg}} which is about the average size of a thylacine.<ref>{{cite journal|first1=Douglass S.|last1=Rovinsky|first2=Alistair R.|last2=Evans|first3=Justin W.|last3=Adams|year=2021|title=Functional ecological convergence between the thylacine and small prey-focused canids|journal=BMC Ecology and Evolution|volume=21|issue=1 |at=58|doi=10.1186/s12862-021-01788-8 |pmid=33882837 |pmc=8059158 |doi-access=free }}</ref><ref name="REMA"/>

A 2005 study showed that the thylacine had a high [[bite force quotient]] of 166, which was similar to that of most quolls, indicating that it may have been able to hunt larger prey relative to its body size.<ref>{{Cite journal |pmc = 1564077|year = 2005|last1 = Wroe|first1 = S.|title = Bite club: Comparative bite force in big biting mammals and the prediction of predatory behaviour in fossil taxa|journal = Proceedings of the Royal Society B: Biological Sciences|volume = 272|issue = 1563|pages = 619–625|last2 = McHenry|first2 = C.|last3 = Thomason|first3 = J.|pmid = 15817436|doi = 10.1098/rspb.2004.2986}}</ref> A 2007 study also suggested that it would have had a much stronger bite force than a dingo of similar size, though this particular study argued that the thylacine would have hunted smaller prey.<ref name=W07/> A biomechanical analysis of the 3D skull model suggested that the thylacine would have likely consumed smaller prey, with its skull displaying high levels of stress that are not suited to withstand forces, and with its bite forces being estimated at a smaller value than that of Tasmanian devils.<ref name="autogenerated1">{{Cite journal |last1=Attard |first1=M. R. G. |author-link=Marie Attard |last2=Chamoli |first2=U. |last3=Ferrara |first3=T. L. |last4=Rogers |first4=T. L. |last5=Wroe |first5=S. |year=2011 |title=Skull mechanics and implications for feeding behaviour in a large marsupial carnivore guild: The thylacine, Tasmanian devil and spotted-tailed quoll |journal=Journal of Zoology |volume=285 |issue=4 |page=292 |doi=10.1111/j.1469-7998.2011.00844.x}}</ref> A 2014 study compared the skull of a thylacine with that of modern [[dasyurid]]s and an earlier [[thylacinid]] taxon ''[[Nimbacinus]]'' based on biomechanical analysis of their 3D skull models; the authors suggested that while ''Nimbacinus'' was suited to hunt large prey with a maximum muscle force of {{cvt|651|N}} which are similar to that of large Tasmanian devils, the thylacine skull displayed a much higher stress in all areas compared to its relatives due to its longer snout.<ref name=A14>{{Cite journal |doi = 10.1371/journal.pone.0093088|pmid = 24718109|pmc = 3981708|title = Virtual Reconstruction and Prey Size Preference in the Mid Cenozoic Thylacinid, Nimbacinus dicksoni (Thylacinidae, Marsupialia)|journal = PLOS ONE|volume = 9|issue = 4|pages = e93088|year = 2014|last1 = Attard|first1 = Marie R. G.|last2 = Parr|first2 = William C. H.|last3 = Wilson|first3 = Laura A. B.|last4 = Archer|first4 = Michael|last5 = Hand|first5 = Suzanne J.|last6 = Rogers|first6 = Tracey L.|last7 = Wroe|first7 = Stephen|bibcode = 2014PLoSO...993088A|doi-access = free}}</ref> If the thylacine were indeed specialised for small prey, this specialisation likely made it susceptible to small disturbances to the ecosystem.<ref name="autogenerated1"/>

It has been suggested on the basis of the canine teeth and limb bones that the thylacine was a solitary [[Pursuit predation|pounce-pursuit predator]] that hunted smaller prey with trophic niches similar to relatively smaller canids like the [[coyote]], and that it was not as specialised as large canids, hyaenids and felids of today: its canine lacked the adaptation for producing slashing or deep penetrating bites, and its anatomy was not suited for running fast in high speed.<ref>{{cite journal |last1=Jones |first1=M. E. |last2=Stoddart |first2=D. M. |year=1998 |title=Reconstruction of the predatory behaviour of the extinct marsupial thylacine (''Thylacinus cynocephalus'') |journal=Journal of Zoology |volume=246 |issue=2 |pages=239–246 |doi=10.1111/j.1469-7998.1998.tb00152.x}}</ref><ref>{{cite book |last=Jones |first=M. E. |title=Predators with Pouches: The Biology of Carnivorous Marsupials |publisher=CSIRO Publishing |year=2003 |isbn=9780643066342 |editor1=Jones |editor-first=M. E. |location=Collingwood, Australia |pages=285–296 |chapter=Convergence in ecomorphology and guild structure among marsupial and placental carnivores |editor2=Dickman |editor-first2=C. |editor3=Archer |editor-first3=A.}}</ref> However, the trappers reported it as an [[ambush predator]] hunting alone or in pairs mainly at night.<ref name="ABRS" /><ref>{{cite journal |last1=Janis |first1=C.M. |last2=Wilhelm |first2=P.B. |year=1993 |title=Were there mammalian pursuit predators in the Tertiary? Dances with wolf avatars |journal=Journal of Mammalian Evolution |volume=1 |issue=2 |pages=103–125 |doi=10.1007/bf01041590|s2cid=22739360 }}</ref> The elbow joint morphology and the forelimb anatomy of the thylacine also suggest that the animal was most likely an ambush predator.<ref>{{cite journal|last1=Figueirido|first1=B.|last2=Janis|first2=C.M.|year=2011|title=The predatory behaviour of the thylacine: Tasmanian tiger or marsupial wolf?|journal=Biology Letters|volume=7|issue=6 |pages=937–940|doi=10.1098/rsbl.2011.0364|pmid=21543392 |pmc=3210661 }}</ref><ref>{{cite journal|last1=Janis|first1=C.M.|last2=Figueirido|first2=B.|year=2014|title=Forelimb anatomy and the discrimination of the predatory behavior of carnivorous mammals: The thylacine as a case study|journal=Journal of Morphology|volume=275|issue=12|pages=1321–1338|doi=10.1002/jmor.20303|pmid=24934132 |s2cid=25924022 }}</ref>

The [[stomach]] of a thylacine was very muscular, capable of distending to allow the animal to eat large amounts of food at one time, probably an adaptation to compensate for long periods when hunting was unsuccessful and food scarce.<ref name="ABRS" /> In captivity, thylacines were fed a wide variety of foods, including dead rabbits and wallabies as well as beef, mutton, horse and, occasionally, poultry.<ref name="P96">[[#Paddle|Paddle (2000)]], p. 96.</ref> There is a report of a captive thylacine that refused to eat dead wallaby flesh or to kill and eat a live wallaby offered to it, but "ultimately it was persuaded to eat by having the smell of blood from a freshly killed [[wallaby]] put before its nose."<ref name="P32">[[#Paddle|Paddle (2000)]], p. 32.</ref>