The Tasmanian wolf is also known as the Tasmanian tiger, but it is neither a wolf nor a tiger. It is a now extinct marsupial and predator that lived in Australia, New Guinea and Tasmania, where the last specimen died in a zoo in 1936. The Tasmanian wolf was striped, had a long tail and was rather dog-like. The animals whose DNA has now been studied lived in zoos in Washington, D.C., and London and were preserved at the Smithsonian Institution and the Swedish National Museum of Natural History in Stockholm, respectively.
"It was fascinating to discover that the two animals were so similar. The genetic variation between them was very small," says Anders Götherström, a researcher at Uppsala University who, together with his colleague Love Dalén, initiated the project and was responsible for the DNA extraction and some of the phylogeny work, among other things.
"Little genetic variation is characteristic of animals that are threatened with extinction today, and now we can see the same thing in the Tasmanian wolf more than 70 years after it died out."
According to these scientists, too little genetic variation can lead to, among other things, a limited ability to withstand bacterial infections or other stress from the environment. The DNA that was analyzed is mitochondria DNA extracted from the hair of the museum specimens. Besides the Tasmanian wolves' own DNA, the researchers found DNA from other organisms, including microorganisms that proved to be very different depending on what conservation technique had been used. One of the animals was preserved in ethanol (Stockholm) and the other was kept dry as a hide in room temperature (Washington). These findings tell us a great deal about bacterial attacks after an animal has been prepared for museum purposes and in the long run can lead to better techniques for enhanced preservation.
There has been a great deal of interest in examining the Tasmanian wolf, both because it was the largest predator in Australia in modern times and because its evolution is similar to that of the wolf in many respects. But even though attempts have been made in the past, this is the first time anyone has succeeded in extracting substantial amounts of DNA from the material.
Götherström has previously been involved in other DNA studies using archeological material, including a number of different extinct animal species and fossils of excrement from the indigenous peoples of America.
For more information, please contact Anders Götherström, phone: +46 (0)18-471 64 83; firstname.lastname@example.org