Climatic change decimates Tasmanian devil's numbers

Climatic change over the past 30,000 years has decimated the numbers of Tasmanian devils, an Australian animal species which is currently on the verge of extinction, according to a study released Wednesday.

One of the authors of the study, Adelaide University biologist Jeremy Austin, has said in the past that these animals suffered two declines in numbers and these two drops coincided with a change in the climate.The research, published in the Biology letters journal, used statistical methods to analyse the genetic data of 300 modern and historic Tasmanian devil specimens to study the variations in the population size.

The results showed that the species suffered a crisis more than 20,000 years ago, during the last Ice Age, and another 3,000 to 4,000 years ago when the level of the El Nino Southern Oscillation phenomenon increased and lands became more arid and there was less food."These data conclusively say that Tasmanian devils have been living with low genetic diversity for a very long period of time and that their populations have gone through major fluctuations over the past 20,000 to 30,000 years," Austin told the ABC television channel.

The biologist said that the loss in genetic diversity of these animals occurred before British rule in the 19th century."Given all the climate predictions for the future pointing towards Australia having a more arid climate, again I think it has big implications for the devils," said Anna Brunche-Olsen, another author of the study from the University of Tasmania.The Tasmanian devil was once widespread in Australia, but today it is restricted to the island of Tasmania where its survival is threatened by facial tumour disease and low genetic diversity.

The Tasmanian devil is a carnivorous animal the size of a small dog. It is the largest carnivorous marsupial in the world and is characterised by its stocky and muscular build, black fur, pungent odour, extremely loud and disturbing screech, keen sense of smell, and ferocity when feeding. The animal has a large head and neck, which allow it to generate amongst the strongest bite per unit body mass of any extant mammal land predator.

The Tasmanian Devil is included in the Australian national list of endangered species and also in the UN Red list for becoming extinct within 25 to 35 years if a cure for its cancer is not found.