LAHORE (Pakistan) • A team of Pakistani researchers claims to have unearthed a 1.1 million-year-old stegodon tusk in the central province of Punjab, potentially shedding new light on the mammal's evolutionary journey.
Stegodons, distant cousins of modern elephants, are thought to have been present on earth from around 11 million years ago until the late Pleistocene period, which lasted until the end of the last Ice Age around 11,700 years ago.
The tusk measures about 2.4m in length and is around 20cm in diameter, making it the largest one to be discovered in the country, according to the team.
It was found by researchers from the zoology department of the University of Punjab during an expedition in the Padri village of Jhelum district, said university spokesman Khurram Shahzad.
Professor Muhammad Akhtar, who led the research trip, said: "This discovery adds to our knowledge about the evolution of the stegodon, particularly in this region.
"It also sheds light on what the environment was like at the time of the animal's life."
Dr Gerrit Van Den Bergh, a palaeontologist at the University of Wollongong in Australia who has done extensive research on the ancient mammals, including in Pakistan, said: "If you have a complete tusk, that's quite special - they are quite rare."
He cautioned, however, that further verification, including of the dating, would be required.
Prof Akhtar said the fossil belonged to the late Pleistocene period and its age was determined using a uranium-lead radioactive dating technique.
Stegodons were known for their long, nearly straight tusks and low-crowned teeth with peaked ridges.
The latter characteristic indicated that they were browsers or mixed feeders in a forested environment, in contrast to the high-crowned plated molars of mammoths and elephants which allowed them to graze.
Stegodons were strong swimmers and are thought to have originated in Africa but to have quickly spread to Asia, where most remains have been found.