Paleontologists have identified what they believe to be the oldest dinosaur fossils in existence. This new dinosaur discovery possibly challenges current beliefs on dinosaur history.
Several decades ago some fossils were discovered in Tanzania. A team of British and U.S. researchers, who have been examining the remains, believe the dinosaur's remains date back to the Middle Triassic period and are approximately 243 million years old, reports the Daily Telegraph.
Currently, the oldest dinosaur remains known come from the Late Triassic period. The Tanzania find is estimated to be 10 million years older than previous fossil discoveries.
The dinosaur is called Nyasasaurus parringtoni, and named for the man that found the fossils in the 1930s, a British paleontologist named Rex Parrington, of the University of Cambridge, who had been working in the Ruhuhu Valley of southern Tanzania.
For decades the bones have been stored in the Natural History Museum in London and were never formally documented.
As research on the fossils was conducted, researchers believe Nyasasaurus parringtoni stood upright, and was about three feet (80 centimeters) high and approximately 10 feet (3 meters) long. It is believed the dinosaur's tail was about five feet long (1.5 meters) and is estimated to have weighed about 45-135 pounds (20-60 kilos), reported AFP.
This suggests that dinosaurs did not start out as humongous, fierce animals, but possibly the various dinosaur species grew larger over time.
"If the newly-named Nyasasaurus parringtoni is not the earliest dinosaur, then it is the closest relative found so far," said Sterling Nesbitt of the University of Washington, and lead author of the report.
According to several media reports, for over a century there have been theories that dinosaurs were in existence before the Late Triassic period and researchers believe they now have confirmed evidence through this find.
"For 150 years, people have been suggesting that there should be Middle Triassic dinosaurs, but all the evidence is ambiguous," Nesbitt indicated.
Live Science gives a description on how researchers made their determinations.
"Previous to this find, all the oldest dinosaurs were all equally old from the same place in Argentina, and those sediments are about 230 million years [old]. So this pushes the dinosaur lineage or the closest relative to dinosaurs all the way back to the Middle Triassic," Nesbitt said during a telephone interview with Live Science. "This is our best evidence of a Middle Triassic dinosaur."
The full paper appears in Biology Letters, a journal of Britain's Royal Society, published on Dec. 5.