Where did the first dinosaurs evolve? Scientists may have found the location

Dinosaurs long dominated Earth’s land ecosystems with a multitude of forms including plant-eating giants like Argentinosaurus, meat-eating brutes like Tyrannosaurus and weirdos like Therizinosaurus, with its Freddy Krueger-like claws.

But the origin of dinosaurs – precisely when and where they first appeared – remains a bit of a puzzle.

Researchers are now proposing a surprising location for the birthplace of dinosaurs, based on the locations of the currently oldest-known dinosaur fossils, the evolutionary relationships among these early forms and Earth’s geography during the Triassic Period.

This locale spans the modern-day Sahara desert and Amazon rainforest regions, now separated by thousands of kilometres and an ocean thanks to a geological process called plate tectonics.

“When dinosaurs first appear in the fossil record, all the Earth’s continents were part of the giant supercontinent Pangaea. Dinosaurs emerged in the southern portion of this land mass, known as Gondwana,” said Joel Heath, a palaeontology doctoral student at University College London and the Natural History Museum in London, and lead author of the study published on Thursday in the journal Current Biology.