Paleobiologist's dicovery of the teleocrater rhadinus — the earliest-known dinosaur relative — has overturned popular predictions as the six-foot-long lizard-like creature was found to have walked on four legs like a crocodile and was not dinosaur-like.
For decades, scientists have wondered what the earliest dinosaur relatives looked like. Most assumed that they would look like miniature dinosaurs, be about the size of a chicken, and walk on two legs.
The findings, published in the journal Nature, revealed that this carnivorous creature, unearthed in southern Tanzania, was approximately seven to 10 feet long, with a long neck and tail, and instead of walking on two legs, it walked on four crocodylian legs.
"The discovery of teleocrater fundamentally changes our ideas about the earliest history of dinosaur relatives. It also raises far more questions than it answers," said lead author Sterling Nesbitt, assistant professor at the Virginia Polytechnic Institute and State University.
The discovery fills a critical gap in the fossil record.
Teleocrater, living more than 245 million years ago during the Triassic Period, pre-dated dinosaurs, were widespread during the Triassic Period and lived in modern day Russia, India, and Brazil.
Furthermore, these cousins existed and went extinct before dinosaurs even appeared in the fossil record, the researchers said.
The intact ankle bones and other parts of the skeleton of the new specimens of teleocrater, helped scientists determine that the species is one of the oldest members of the archosaur tree and had a crocodylian look.
"The teleocrater has unexpectedly crocodile-like features that are causing us to completely re-assess what we thought about the earliest stages of dinosaur evolution," explained Ken Angielczyk, associate curator at The Field Museum of Natural History– a natural history museum in Chicago, US.
"Surprisingly, early dinosaur relatives were pretty profoundly not dinosaur-like," Angielczyk added.