Violent foreplay linked to spread of mystery illness

A rare and horribly disfiguring disease that has devastated the Tasmanian devil is probably being transmitted by the creature's singularly unpleasant social habits and boisterous sex life, Australian scientists believe.

The devil has been wiped out in many parts of the island state over the last three years.

Numbers have fallen from about 150,000 to less than half that, with 80 per cent mortality in some areas.

Researchers believe the animals' penchant for fighting over decaying carrion and for engaging in violent foreplay could account for the speed with which the disease has spread.

The mystery illness, which was first noticed about five years ago and has now spread to two-thirds of Tasmania, results in hideous facial tumours which eventually leave devils so swollen and disfigured that they cannot see or eat.