One of the oldest fossils ever discovered might finally unravel the mystery of how ordinary lizards evolved into dinosaurs.
Paleontologists identified a 237-million-year-old, four-legged, new reptile species roughly the size of a small dog in Brazil.
The newly found species, named Gondwanax paraisensis, featured several features common among the early ancestors of dinosaurs, with some that have never found before.
The team believes that the fossil characteristics could help fill in the gaps in the evolutionary history.
Above, paleontologist Rodrigo Temp Müller holds a fossil of the new species, called ‘Gondwanax paraisensis,’ next to a contemporary fossil of ‘Prestosuchus chiniquensis,’ a species that also lived 237 million years ago
This ancient reptile was first discovered by a local doctor in the town of Paraiso do Sull, who later donated the fossil in 2021.
A re-analysis of the remains, conducted by researchers at the Federal University of Santa Maria, found the creature roamed the country during the Triᴀssic period when mammals, crocodiles, turtles and frogs all first came into being.
The arrival of other animals meant the ancient reptile had to compete for survival due to them all residing on what was the supercontinent of Pangea, which had a ferocious jungle ecosystem sweltering in a climate far H๏τter than ours today.
The reptile has some features that have been found among dinosaur ancestors, known as silesaurids, such as a notch below the head of the thigh bone and a flat surface on the top of the femur where it connects to the hip.
The traits helped scientists determine that Gondwanax paraisensis had to be one of the oldest known silesaurids.
But the team identified a unique bone feature that connected the spine to the hips.
This area, known as a sacrum, was composed of three vertebrae
The 39-inch-long, up to 13-pound lizard’s name means ‘lord of Gondwana’ in honor of in the southernmost region of the Pangaea, known as the Gondwana landmᴀss.
Paleontologist Rodrigo Temp Müller noted that the creature’s vertebrae showed it was likely an ‘agile and lightweight animal.’
Its unique, compeтιтive abilities and its presence near so many other fossils from this same Triᴀssic period will help researchers understand the ecosystem in which dinosaurs first evolved.
‘Because it’s so old, it gives us clues as to how dinosaurs came to be,’ said Müller.
‘The most important part of this finding is its age,’ he explained.
Above, an illustration of ‘Gondwanax paraisensis,’ now believed to be an ‘agile and lightweight’ predecessor to the dinosaurs – dating back 237 million years
Paleontologist Müller holds up fossilized piece of Gondwanax paraisensis’ vertebrae
Paleontologists have long debated whether silesaurids were, themselves, true dinosaurs, simply ‘non-dinosaur dinosauriforms,’ or potentially a ancestor to these famous and gigantic creatures that once ruled the Earth.
‘Understanding the characteristics of these precursors could shed light on what was crucial for the dinosaurs’ evolutionary success,’ Müller and his team said in a statement.
And the region itself played a key role in the major evolutionary shifts that occurred.
