An ancient stegodon tusk (elephant-like animal) that was unearthed in Pakistan may provide clues to the evolution of modern-day elephants, according to a new study.
Researchers with the University of Punjab have found the intact tusk of a stegodon, a distant cousin of the modern elephant that is thought to have lived about 1.1 million years ago.
According to university officials, the tusk was eight inches (about 20 cm) across and eight feet (2.4 m) long. The new discovery could shed some light on the lives of an extinct genus of the elephant family.
Professor Muhammad Akhtar, a scientist and Director General of the School of Biological Sciences, at the University of the Punjab, said that the stegodon tusk provides evidence not only to the evolution of the animal, but also to the state of the environment when the animal was alive.
Dr. Gerrit van den Bergh, a palaeontologist and stegodon expert, said that the tusk – which is estimated to date back to the late Pleistocene period (about 1.1 million years ago) – may need further verification.
To find out the tusk’s age, Professor Akhtar used uranium/lead radioactive dating method – which compares the ratio of lead-206 to uranium-238 to calculate object’s age; the more lead-206 there is, the older the object is, the researchers said.
Although stegodon fossils are not the uncommon, very few of them manage to survive intact for one million years. Dr. Bergh said that complete tusks are quite rare and special.
Compared with the most members of the elephant family tree, stegodon tusks are a lot straighter. Based on their teeth with peaked ridges and low crowns, researches said that the stegodonts lived in forested areas and had mixed diets.
According to the Fossilworks database, the animal originated in Africa, and then spread throughout Asia. Although stegodonts are mostly an Asian species, a molar fragment was also found in Greece, Van der Bergh said.
On Flores, one of the Lesser Sunda Islands, researchers have discovered fossils of a dwarf population of the elephantoid which may have survived longer its larger ancestors. According to Van der Bergh, elephantoid fossils are often found on other islands in the region due to their great ability to colonize islands.
Image Source: wikimedia