Washington, May 5 : Based on the scars discovered on the jaw of a 120 million-year-old marine reptile, scientists have suggested that life might not have been that easy in the ancient polar oceans.

The healed bite wounds, probably made by a member of the same species, give an important insight into the social behaviour of extinct sea creatures from the time of the dinosaurs.

Found in the remote desert near the town of Marree in northern South Australia, the fossilised skeleton belonged to an ichthyosaur, a dolphin-like marine reptile that lived during the ''Age of Dinosaurs''.

Ichthyosaurs were fast swimming predators that fed on fish and squid-like animals. Adults would have been around six metres in length and had long-snouted heads with over 100 pointed, crocodile-like teeth.

The surprising discovery of well-preserved bite marks on the bones of the ichthyosaur''s lower jaw were made during painstaking cleaning and reassembly of its skeleton in the laboratory.

Evidence of advanced healing indicates that the animal survived the attack and lived on for some time afterwards.

"Pathological traces on ancient fossilised bones and teeth give unique insights into the lives and social behaviours of extinct animals," said Benjamin Kear, one of the authors of the study and an Assistant Professor with the Palaeobiology Programme at Uppsala University.

The size and spacing of the tooth marks do match any potential predators or prey.

Rather, they are most consistent with another adult ichthyosaur, suggesting that the wounds were inflicted during combat over food, mates or territory.

The finding is described in a forthcoming issue of Acta Palaeontologica Polonica. (ANI)