/ 11 November 2009

New species of dinosaur discovered in SA

Scientists at the University of the Witwatersrand on Wednesday announced the discovery of a new species of dinosaur.

”It’s one of the big jewels South Africa has,” Dr Adam Yates, from the Bernard Price Institute for Palaeontological Research, told journalists in Johannesburg.

The dinosaur, Aardonyx Celestae, was named after Yate’s wife, Celeste, who was responsible for removing the bones from its casing of concrete-like rock.

”She spent over two years and two pregnancies removing the rock,” said Yates.

The rock also provided the other part of the dinosaur’s name, Aardonyx, which means ”earth claw”.

Fossils from two Aardonyx were found, one which was 7m long and the other 9m long. They are an estimated 195-million years old, dating from the early Jurassic period, and were herbivores.

Due to its underdeveloped bone structure, it is believed that the fossils recovered were from juveniles only between seven and 10 years old. An adult Aardonyx may have been larger than those found.

Yates said the dinosaur shared traits of evolutionary precursors to the sauropods, which dominated the Jurassic period. Sauropods were plant eaters that walked on four-legs and dominated the Jurassic period. Aardonyx, by contrast, walked on two legs but is believed to have occasionally also used its forelegs to walk.

For this reason it was a ”living fossil” that would have been old, even amongst other dinosaurs.

”It is in effect a living fossil …it’s a primitive holdover from an earlier period,” said Yates.

However, like sauropods living at the time, Aardonyx grazed by stripping vegetation from branches with its small teeth.

”Aardonyx gives us a glimpse into what the first steps toward becoming a sauropod involved,” said Yates. ”Its tells us the changeover was not smooth, and the evolution was complicated.”

Aardonyx was found on a farm in the Senekal district of Free State. The farm was owned by Cobus Visser who gave his permission for the dig.

It was one of three new dinosaur species found in the area. Also found was a single tooth from a carnivorous dinosaur near Aardonyx’s remains.

”But we don’t know if it killed it or found its carcass and took advantage of a free meal,” said Yates.

He said the carnivore tooth was also an exciting find because of its size, which would be much larger than other carnivorous dinosaurs in the area at the time. Further fossil evidence was needed before a new species was declared, however.

Yates said because of the number of dinosaurs found in the area it was likely the area was the location of a ”palaeontological oasis”, a lush, green spot amid the arid floodplain that was prehistoric South Africa.

Because so many fossils have been found in the same time period, it is possible they were casualties of a drought which affected the area. — Sapa