Researchers at the China University of Geosciences in Wuhan have recently discovered fossils of an extinct branch species of tiger that are more than 43,500 years old.
Researchers have named the species the "Da'an tiger" after the location where the fossils were discovered in Northeast China's Jilin province, the university said in a statement.
"This is a rare research discovery－the first time in the world the genome of this ancient tiger species has been discovered," it said.
News of the discovery, made by the university's ancient DNA team headed by professor Lai Xulong and counterparts from China's Jilin University and Denmark's University of Copenhagen, was recently published in the British journal, Proceedings of the Royal Society B: Biological Sciences.
Sheng Guilian, a professor at the School of Environmental Studies at the China University of Geosciences, said the discovery is the first to prove the existence of other tiger lineages from the perspective of genetics, proving that the species has a longer and more complex history of evolution.
"The research offers additional clues to help trace the lineal ancestors of modern tigers," Sheng said.
The specific reason for the extinction of the Da'an tiger remains to be determined, she said.
Biologically, tigers belong to the Panthera genus of the cat family. Today, there are six living subspecies worldwide－the Siberian tiger, the South China tiger, the Indo-Chinese tiger, the Bengal tiger, the Malay tiger and the Sumatran tiger. Scientists believe they all descend from the same ancestral population, which has a history spanning some 110,000 years.
But the Da'an tiger is a new branch that does not genetically belong to the same ancestral population of other modern tigers.
"Even going back 260,000 years, the ancestral population of the Da'an tiger had already separated from the ancestors of existing tigers," a statement from the university said.
The oldest tiger fossil discovered in China, which dates back 2 million years to the Early Pleistocene, was found in Gansu province.
According to a report released last month by the China Biodiversity Conservation and Green Development Foundation, the country has a population of 7,116 tigers, including Siberian, South China, Indo-Chinese and Bengal tigers. Of them, only 73 are estimated to be living in the wild.