Tasmanian Tiger - Thylacinus cynocephalus

Photo: Tasmanian Tiger pair in Hobart Zoo, Tasmania, Australia (pre-1921). The female is in the foreground and the male in de background.

This image is of Australian origin and is now in the public domain, because its term of copyright has expired. According to the Australian Copyright Council(ACC), ACC Information Sheet G23 (Duration of copyright) (Feb 2008).

Didelphis cynocephala Harris, 1808; Thylacinus harrisii Temminck, 1824; Dasyurus lucocephalus Grant, 1831; Thylacinus striatus Warlow. 1833; Thylacinus communis Anon. 1859; Thylacinus breviceps Krefft, 1868.

G.P. Harris, who authored the scientific description of the Tasmanian tiger, focused on the structure of the animal's head and in April, 1807 named the species Didelphis cynocephala, which translates to "dog-headed opossum". The Parisian zoologist E. Geoffroy Saint-Hilaire, in 1809, assigned the Tasmanian tiger to the genus Dasyurus along with the marsupial "martens" (quolls).  Unsatisfied with this classification, Conrad Jacob Temminck created (in 1827) (or 1824 according to some references) the genus name that we use today, Thylacinus. The species established by G.P. Harris (cynocephalus) remains valid.

The Tasmanian Aboriginals called the Tasmanian Tiger coorinna, loarinna, laoonana, or lagunta.  These native names did not achieve any popular usage and disappeared with the extinction of the Tasmanian Aborigines.

The Tasmanian tiger or Thylacine was by far the largest carnivorous marsupial of recent times. Its overall appearance is very canid-like. Total body length is around 1 meter. The tail length is around 50-65 cm. The tail itself is very thick close to the body and quickly tapers to a point. It is around 60 cm in height at the shoulder. The upper body is brownish/grey with a pale underside. There are 13-19 black vertical stripes that run from the mid-back to the base of the tail. The face is grey with white markings around the eyes. The fur is short and thick. Their skull has a length of 22 cm and the dental formula is: i 4/3, c 1/1, pm 3/3, m 4/4. Tasmanian tiger's long canines, shearing premolars, and grinding molars, all of which are quite similar to those of dogs. The feet are padded and leave a five-toed print. The females pouch is located by her tail and has a fold of skin covering the four mammae.

The food habits of the Tasmanian tiger are not well known. Its diet is thought to have consisted of wallabies, kangaroos, small birds, and other small mammals.

The breeding season is thought to have taken place in the fall. Births occurred continuously throughout the year, but were concentrated in the summer months (December-March). It is believed that the young (usually 2-4) stayed in the pouch for 3 months and remained with the mother for another 6 months.

Photo: One of only two known photos of a Thylacine with a distended pouch, bearing young. Adelaide Zoo (South Australia, Australia), 1889. This image is of Australian origin and is now in the public domain because its term of copyright has expired. According to the Australian Copyright Council(ACC), ACC Information Sheet G23 (Duration of copyright) (Feb 2008).

The Tasmanian tiger was a nocturnal species, but was often observed basking in the sun. It hunted alone or in small groups. There is a controversy over the Tasmanian tiger's hunting technique. Some think that the Tasmanian tiger was an ambush hunter that relied on stealth while others think the Tasmanian tiger would tirelessly chase its prey until the target was exhausted, when it would rush in for the kill. The Tasmanian tiger had many different calls, including a rough bark while hunting, deep growl when irritated, and a whine.

In prehistoric times the Tasmanian tiger ranged from Tasmania, mainland Australia to New Guinea. However, in recent times the Tasmanian tiger was restricted to the Australian island of Tasmania. The Tasmanian tiger preferred open forests and open grasslands, but by the end of its existence it was confined to dense rainforests by human pressures Tasmanian tiger lairs were located mainly in hollow logs or rock outcroppings located in hilly areas that were adjacent to open areas, such as grasslands.

Image: map with the location of Tasmania, the historical distribution of the Tasmanian Tiger (in red). Created by Peter Maas for The Sixth Extinction Website. This image has been licensed under the Creative Commons Attribution Non-commercial No Derivatives 3.0 licence.

Tasmanian tigers lived only on the island of Tasmania in recent history, but fossil record shows that it was also found in New Guinea and Australia as recently as 3000 years ago. Competition with dogs brought by aborigines eliminated it in Australia and New Guinea. These dogs ran wild, becoming the dingo, which entirely filled its niche. A large population survived on Tasmania, where there are no dingoes.

When the Europeans arrived and settled in Australia and Tasmania the Tasmanian tiger was thought to be a livestock killer, especially when sheep were introduced in 1824. This was never substantiated, but because of this misconception the privet sector and the government hunted the Tasmanian tiger from 1830-1909 for bounty. In 1830, the Van Diemens Land Company, a pastoral company in Northwest Tasmania, introduces the first bounty on the Tasmanian tiger, claiming that the animal attacked sheep. In 1880, the Tasmanian Parliament placed a price of one pound per Tasmanian tiger scalp. In 1909, the government bounty scheme was terminated. Between 1888 and 1909 a total of 2184 bounties were paid. The actual number of killed Tasmanian tigers must have been even higher.

Photo: This iconic image of a bagged Tasmanian Tiger or Thylacine (Thylacinus cynocephalus) featuring Mr. Weaver in a studio portrait is repeatedly published yet it is not attributed. It may have been taken by Victor Albert Prout who sojourned briefly in Tasmania in the late 1860s but is known and praised for his excellent panoramas of Sydney Harbour by contemporary photohistorians. This image is of Australian origin and is now in the public domain because its term of copyright has expired. According to the Australian Copyright Council(ACC), ACC Information Sheet G23 (Duration of copyright) (Feb 2008). This applies also to the European Union, the United States, Canada and those countries with a copyright term of life of the author plus 70 years.

The animal became very rare, due to hunting, habitat destruction, disease, and competition with domesticated dogs. The last known alive, named Benjamin, was trapped in Florentine Valley in 1933 and sold to the Hobart Zoo, where it died in captivity on the 7th September 1936. The day-shift keeper forgets to lock the Tasmanian tiger up in its hut and it dies of exposure. Tasmanian law did not protect the Tasmanian tiger until 1936, the same year of their extinction. So it was too late!

Photo: The last known thylacine photographed at Hobart (formerly Beaumaris) Zoo in 1933. A scrotal sac is not visible in this or any other of the photos or film taken, leading to the supposition that "Benjamin" was a female, but the existence of a scrotal pouch in the thylacine makes it impossible to be certain. This image is of Australian origin and is now in the public domain, because its term of copyright has expired. According to the Australian Copyright Council(ACC), ACC Information Sheet G23 (Duration of copyright) (Feb 2008).

Since then there have been many unsuccessful searches of the remaining area where the Tasmanian tiger could have survived undetected by humans. A 647000 ha. Reserve was set up in 1966 in Southwestern Tasmania in the hopes that possible surviving Tasmanian wolves would have adequate habitat.

The Tasmanian tiger has never been officially or reliably sighted since the last one died in 1936. The Tasmanian tiger was officially declared extinct by international standards in 1986.

The Tasmanian Tiger died out on the Australian mainland and New Guinea due to the competition of the dingo that was brought there by the aborigines. The last remaining population on Tasmania declines after the arrival of the Europeans, and finally died out, due to extensive (bounty) hunting, habitat destruction, disease, and competition with domesticated dogs.

Tasmanian law did not protect the Tasmanian tiger until 1936, the same year of their extinction. A 647,000 hectare sanctuary was created in southwestern Tasmania in 1966 in the hope that if any Tasmanian tiger persist there, they can at least live an unpressured existence, and perhaps even breed.  Legal protection came too late for the Tasmanian tiger, as it was not granted until 1936.  It is classified as endangered by the IUCN (1972) and the USDI (1980). The species is also registered on appendix I of the CITES listing, however, the Australian government has suggested its removal since the general attitude is that the species is now extinct.

The project to bring the Tasmanian tiger back from extinction began in 1999 when Australian Museum scientists extracted DNA from an ethanol-preserved female pup in its collection.

In 2001, further DNA was extracted from two other preserved pups; the tissue source for the DNA was bone, tooth, bone marrow, and dried muscle. Dr. Mike Archer, director of the Australian Museum, said the alcohol-preserved female pup's DNA had given the scientists the Tasmanian tiger's X chromosome and the other samples the male Y chromosome.

On 28 May 2002, the scientists from the Australian Museum in Sydney announced a breakthrough in efforts to clone the extinct Tasmanian wolf, saying they had replicated some of the animal's genes using a process called PCR (polymerase chain reaction). These PCR's show that short fragments of the DNA are undamaged and undoubtedly Tasmanian Tiger DNA, and that there is no reason why these should not work in a living cell.

The next stage is to make large quantity copies of all the genes of the Tasmanian tiger so these can be used to construct synthetic chromosomes. The scientists said they hoped to clone a Tasmanian tiger in 10 years if they were successful in constructing large quantities of all the genes of the Tasmanian tiger and sequencing sections of the genome to create a genetic library of Tasmanian tiger DNA.

But Dr. Mike Archer said the technology for the final stage of cloning, putting the Tasmanian tiger's genetic material into a Tasmanian devil host cell which has been stripped of the devil's genetic material was still to be developed. "We don't know the length of this journey. It's up to the speed with which technology keeps pace with the vision. But I am optimistic," he said. The ultimate aim of this project was to clone a viable reproducing population of Tasmanian tigers in the wild.

On 15th February 2005 sad news appeared. The resurrection of the Tasmanian tiger will have to wait. After five years trying to extract DNA from preserved Tasmanian tigers in an effort to bring the lost marsupial back to life, the Australian Museum has abandoned the ambitious project, after finding its supply of Tasmanian tiger DNA too degraded. The museum said it lacked the skills and facilities to continue the project. Professor Archer, now the dean of science at the University of New South Wales, says the cloning project has lost steam since he left the museum in 2003. In a statement to ABC Science Online, Professor Archer says he is disappointed by the museum's decision but he says he still hopes it might be possible to bring the Tasmanian tiger back to life. "I and other colleagues remain interested in the project and I don't think that it will simply die because the museum can't proceed," he says. "The technology to make it happen is improving all the time. And I believe science has a duty to continue to assemble the building blocks that will be needed to do it."

Preserved specimens of the Tasmanian Tiger can be found in museums all over the world. For example in the Natuurhistorisch Museum 'Naturalis' in Leiden (the Netherlands), Rosensteinmuseum in Stuttgart (Germany), Australian Museum in Sydney (Australia), Melbourne Museum (Australia), and many more!

Photo: a Tasmanian tiger in the Rosensteinmuseum in Stuttgart, Germany. Copyright and courtesy by Sordes. All rights reserved.

The phylogenetic position of the Tasmanian tiger within australidelphian marsupials has long been debated. Research published in Genome Research in January 2009 provides strong to support for the Tasmanian tiger's basal position in Dasyuromorphia. This research showed that not the Tasmanian devil (Sarcophilus harrisii), but the numbat (Myrmecobius fasciatus) is the Tasmanian tiger's closest living relative. (Miller et al. 2009; Wikipedia contributors 2010)

Photo: A numbat (Myrmecobius fasciatus) from Perth Zoo, Western Australia, Australia. Photographed by Martin Pot on 19 April 2007. This image is licensed under the Creative Commons Attribution 3.0 Unported license. A full resolution version can be found at Wikimedia Commons.

The Thylacine Museum - A natural history of the Thylacinidae

Thylacine - Wikipedia, the free encyclopedia

Anon. (1859). Descriptive catalogue of the specimens of natural history in spirit contained in the Museum of The Royal College of Surgeons of England. Vertebrata: Pisces, Reptilia, Aves, Mammalia. London : Royal College of Surgeons of England xxii 248 pp. [147] [nom. nov. for for Didelphis cynocephala Harris, 1808; name attributed in this work to Temminck but reference not found].

DEWHA (2008). Thylacinus cynocephalus (Harris, 1808). Australian Faunal Directory. Australian Biological Resources Study. October 9, 2008. Downloaded on 16 August 2010.

Grant, J. (1831). Notice of the Van Diemen's Land Tiger. Gleanings in Science 3: 175-177 [175].

Harris, G.P. (1808). Description of two new species of Didelphis from Van Diemen's Land. Transactions of the Linnean Society of London 1 9: 174-178 pl. 19 [publication date established from Raphael, S. 1970. The publication dates of the Transactions of the Linnean Society of London, Series 1, 1791–1875. Biological Journal of the Linnean Society of London 2: 61–76 [63, 75]] [174].

Krefft, G. (1868). Description of a new species of thylacine (Thylacinus breviceps). Annals and Magazine of Natural History 4 2: 296-297 pl. 17 [296].

Miller, W., et al. (2009). "The mitochondrial genome sequence of the Tasmanian tiger (Thylacinus cynocephalus)". Genome Res. 19 (2): 213–20. doi:10.1101/gr.082628.108.

Temminck, C.J. (1824). Sur le genre Sarigue - Didelphis (Linn.). pp. 21–54 pls 5–6 [and] Sur les mammifères du genre Dasyure, et sur deux genres voisins, les Thylacynes et les Phascogales. pp. 55–72 pls 7–8. In, Temminck, C.J. (ed.). Monographies de Mammalogie, ou description de quelques genres de mammifères, dont les espèces ont été observées dans les différens musées de l'Europe. Ouvrage accompagné de planches d'Ostéologie, pouvant servir de suite et de complément aux notices sur les animaux vivans, publiées par M. le Baron G. Cuvier, dans ses recherches sur les ossemens fossiles. Paris : G. Dufour et E. D'Ocagne Vol. 1. [publication date established from Husson, A.M. 1962. The bats of Suriname. Zool. Verh. 58: 1–282 pls 1–30 [276] and Anon. 1825. Monographies de Mammalogie, ou description de quelques genres de mammifères dont les espèces ont été observées dans les différens musées de l'Europe par C.J. Temminck. Livraisons 1–3 pp. 72 pl. viii. Zoological Journal. London 1: 574–576] [23-24, 63] [nom. nov. for Didelphis cynocephala Harris, 1808]

Warlow, W. (1833). Systematically arranged Catalogue of the Mammalia and birds belonging to the Museum of the Asiatic Society, Calcutta.Journal of the Asiatic Society of Bengal 2: 97-100 [97] [nom. nov. for Didelphis cynocephala Harris, 1808, as Didelphis cynocephalus].

Wikipedia contributors (2010), "Thylacine," Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Thylacine&oldid=379198374 (accessed August 16, 2010).