Monday 5 December 2011

The Oldest Known Tiger On Earth

The skull and lower jaw of Panthera zdanskyi
Tigers are an endangered species. Yet just a few hundred thousand years ago, they were common and could be found across India and South East Asia. Some species even lived as far north as Siberia. The most common-kind is the Indian Panthera tigris. Now scientists believe that they have found its oldest ancestor. The subject of the tigers' origins was once the object of much debate.

The major consensus was that they first evolved in China. This theory has now been confirmed by a recent fossil discovery: a skull and lower jaw unearthed on the slopes of Longdan in the Gansu Province, North-west China, in 2004. It was given a date of around 2.16 to 2.55 million years old making it older than all other pantherine cats, both modern and prehistoric, by a half a million years. It was given the name of Panthera zdanskyi after the late Austrian palaeontologist Otto Zdansky, known for his work on ancient Chinese carnivores.

The skull was robust, with well developed canines, and a long snout. While smaller than most modern day pantherines, a trait common in basal forms, analysis of the bones showed that the tigers have barely changed despite two million years of evolution. 'The discovery of the identity of this fossil is vitally important for providing a greater understanding of the fossil history of big cats and the relationships between them' said Andrew Kitchener, Principal Curator of Vertebrate Biology at National Museums Scotland in Edinburgh.

'It will be interesting to see whether further fossil big cats are discovered in China and elsewhere, which expand our knowledge of the distribution of this species and fill in more gaps in the tigers' fossil history. Confirming a more precise dating of Panthera zdanskyi would also be invaluable for understanding its position in the tigers' evolutionary timescale.' The team also believe that the tigers' diet has barely changed, with all species both modern and prehistoric feeding upon small, quadruped mammals.