A group of archaeologists has found what is believed to be the oldest known relative to the dinosaurs.

Teleocrater rhadinus, a close relative of dinosaurs, feasting on an ancient mammal relative, Cynognathus, in the Triassic of Tanzania. The large dicynodont Dolichuranus is seen in the background. Credit: Natural History Museum, London, artwork by Mark Witton.

The dinosaurs are believed to have evolved sometime approximately 235 million years ago, during what is called the late Triassic geologic period.

This newfound animal named ‘Teleocrater rhadinus’ was not much larger than a medium-sized dog, appears to be 10-15 million years older. It probably lived near the equator on the big continent Pangea.

There was a split at this time in history; between the animals that would later become crocodiles and the animals that gave rise to dinosaurs – eventually evolving into the birds we have around today.

This newfound animals hind legs provide an important clue. While the ankle joints of the dinosaurs are more similar to hinges, the crocodiles are more like a swivel, where some parts are fixed. This animal appears to be a crude mix of both, hence probably the oldest known relative.

The Teleocrater fills a gap in evolutionary history and also a missing piece to a lengthy academic investigation. The Teleocrater and other recently discovered dinosaur relatives show that these animals were widespread during the Triassic Period and lived in modern day Russia, India, and Brazil. They all existed and went extinct before dinosaurs even appeared in the fossil record.

The team of paleontologists unearthed the dinosaur in southern Tanzania and will go back to Tanzania this May to find more remains and missing parts of the Teleocrater skeleton.


Reference:

Sterling J. Nesbitt et al. The earliest bird-line archosaurs and the assembly of the dinosaur body plan. Nature, 2017. DOI: 10.1038 / nature22037