The thylacine however, is a very different story indeed.  A motion picture camera was actually on location to document the pitiful loneliness of the last captive individual's remaining years of life, and thus imprint this sad image into the conscience of an entire planet.

    At the turn of the 21st century however, Professor Michael Archer (then Director of the Australian Museum in Sydney) instigated a bold and ambitious plan to clone the thylacine.
 

Currently the Dean of Science at the University of New South Wales, he is also a professor of palaeontology.  Archer proposes that it might be entirely possible for a living thylacine to be cloned from an infant female preserved in alcohol which has been under the care of the Australian Museum since 1866.     At present, Archer's plan still occupies an area somewhere between the solid reality of Scottish researcher Professor Ian Wilmut's successful cloning of a large mammal - Dolly the sheep - and the science fiction realm of writer Michael Crichton's Jurassic Park dinosaurs, resurrected from fragmented strands of DNA preserved in the blood of fossil mosquitoes sealed in Mesozoic amber.     However, there remains an immense technological void between cloning a common and readily available species such as a sheep or cow, and the cloning of a unique marsupial using only degraded DNA that has been immersed in liquid preservative for about 140 years.  Apart from the difficulties of resequencing the thylacine's complete genome using what genetic material can be obtained from preserved cells, another major obstacle is that there are no truly close relatives in the modern Australian fauna that may possibly offer a surrogate womb for an artificially produced thylacine embryo, or a pouch for any resultant young.

. The Australian Museum's infant female thylacine which has been preserved in alcohol since 1866.

    The thylacine's closest relatives have been extinct for millions of years.  The fossil remains of many of these earlier thylacinids have been found along with a multitude of other extinct marsupials in the extraordinary limestone formation that Archer and his colleagues discovered in the early 1980s at Riversleigh Station, in northwest Queensland.

    Riversleigh provides a rare view of what animals existed in Australian rainforests between about 12 million and 25 million years ago, when the predecessors of the modern-day fauna, along with some now lost marsupial groups which left no descendants, resided in a much warmer and wetter Australia.

    The teeming life of Riversleigh's rainforests provided abundant prey for meat eaters, which included a number of thylacine species as well as early dasyurids.

    The Dasyuridae are a diverse group which includes specialized carnivores such as the Tasmanian devil (Sarcophilus harrisii), and the quolls (Dasyurus sp.), as well as smaller predators and insectivores such as the Brush-tailed Phascogale (Phascogale tapoatafa), dunnarts (Sminthopsis sp.) and tiny Planigale species which weigh less than 10 grams.
 

. A life reconstruction of the prothylacynine borhyaenid marsupial Prothylacynus patigonicus from the Early Miocene of South America (based upon a drawing by M. R. Long).  It was somewhat similar to the thylacine in form, but not ancestral to it.

It wasn't until the early 1980s that the thylacine's position within Australian marsupial taxonomy became truly clear.  Morphologically, the thylacine bears a striking resemblance to the borhyaenids, an extinct family of large wolf-like marsupial predators from South America.  However, in 1982, a comparative study of blood proteins called albumins indicated that the thylacine is in fact a close relative of the dasyurids, and suggested that it had branched off from the main dasyurid line of evolution approximately 12 million years ago.

    A decade later, analysis of DNA recovered from a preserved thylacine pelt provided an even stronger confirmation of this evolutionary affinity. The borhyaenid link was simply another deceptive case of evolutionary convergence: similar lifestyles create similar physical forms.  However, the albumin study also misled evolutionary biologists by underestimating how long ago the thylacinids and dasyurids had diverged from an early proto-dasyurid predecessor.  The recent discoveries of a number of fossil thylacinid species and at least one ancestral dasyurid at Riversleigh from approximately 22 million years ago suggest a minimum divergence time of 25 million years, and possibly even as far back as 30 to 40 million years ago.