The largest carnivorous marsupials in the world, devils once occurred on mainland Australia, but have been confined to Tasmania since before colonisation.
Tasmanian devils are threatened by devil facial tumour disease, a contagious cancer which causes tumours around the mouth, face and neck.
The disease develops rapidly and is fatal: affected animals die within six months of the lesions first appearing.
As of February 2010, it had spread across approximately 60% of Tasmania and caused a rapid decline in wild devil populations.
The species is now listed as endangered.
Image Credit: Photograph by Joel Sartore/joelsartore.com