Newly-discovered fossils suggest giant dinosaurs evolved millions of years earlier than scientists thought
David Williams, CNN • Published 10th July 2018
(CNN) — Recently-unearthed fossils in Argentina suggest that giant dinosaurs roamed the Earth some 30 million years earlier than scientists had previously thought.
The plant-eating dinosaur was a type of sauropodomorph that lived in the Late Triassic period and weighed about 10 tons, according to a study published in the journal "Nature Ecology & Evolution".
Researchers named it "Ingentia prima," from the Latin words huge and first.
"Before this discovery, gigantism was considered to have emerged during the Jurassic period, approximately 180 million years ago, but Ingentia prima lived at the end of the Triassic, between 210 and 205 million years ago," the study's lead author Dr. Cecilia Apaldetti said in a news release.
Early Triassic sauropodomorphs were small and ran on two legs.
Ingentia prima was about three times bigger and traveled on all fours.
The dinosaur had a bird-like respiratory system and air sacs in its bones that helped keep it cool.
The fossils showed that it had cyclical growth, which means that it would have spurts of rapid growth then stop growing for similar periods of time, much like a tree.
Later sauropodomorphs would grow at a steady rate.
Its large size helped protect it from predators and future dinosaurs evolved to grow even bigger.
"We see in Ingentia prima the origin of gigantism, the first steps so that, more than 100 million years later, sauropods of up to 70 tons could come into existence like those that lived in Patagonia," Apaldetti said.
