Pliosaurs had arthritis?

LONDON, May 16: British scientists claim that pliosaurs—not dinosaurs but ancient sea reptiles that lived 150 million years ago—may have had arthritis.
A team at the University of Bristol has found signs of a degenerative condition similar to human arthritis in the jaw of a pliosaur. Such a disease has never been described before in fossilised Jurassic reptiles.
The scientists studied a giant specimen of the pliosaur Pliosaurus dating from the Upper Jurassic. Found in Westbury, Wiltshire, it has been kept since its discovery in collections of the Bristol City Museum and Art Gallery.
The eight-metre-long pliosaur was a terrifying creature with a large, crocodile-like head, a short neck, whale-like body and four powerful flippers to propel it through water in pursuit of prey, the ‘Palaeontology’ journal reported.
With its huge jaws and 20 cm long teeth, it would have been capable of ripping most other marine reptiles or dinosaurs to pieces, but this particular individual was the unfortunate victim of an arthritis-like disease.
Lead scientist Dr Judyth Sassoon said she noticed in the museum collections that it had the signs of a degenerative condition similar to human arthritis, that had eroded its left jaw joint, displacing the lower jaw to one side.
This animal evidently lived with a crooked jaw for many years, because there are marks on the bone of the lower jaw where the teeth from the upper jaw impacted on the bone during feeding. Clearly the animal was still able to hunt in spite of its unfortunate condition.
There are several signs on the skeleton to suggest that the animal could have been an old female who had developed the condition as part of the aging process, say the scientists.
The pliosaur’s large size and the fused skull bones suggest maturity. It is identified, very tentatively, as possibly female because its skull crest is quite low—presumed males had a higher crest, a university release said.
Dr Sassoon said: “In the same way that aging humans develop arthritic hips, this old lady developed an arthritic jaw, and survived with her disability for some time.
“But an unhealed fracture on the jaw indicates that at some time the jaw weakened and eventually broke. With a broken jaw, the pliosaur would not have been able to feed and that final accident probably led to her demise.”
Pliosaurs were probably pursuit or ambush predators, feeding on fish, squid and other marine reptiles but would also have been capable of scavenging. They were at the top of their food chains, so there would not have been any predators to take advantage of an ageing, disabled pliosaur—except for another pliosaur. (PTI)