Fossil Evidence from Tanzania Provides New Insight into Dinosaur Evolution
The Triassic is regarded as a transitional period in the evolution of vertebrates, the Permian mass extinction event devastated the mega fauna of planet Earth, with something like 95% of all species becoming extinct. It was into this brave, new world of the Triassic, that the ancestors of the dinosaurs evolved and they, plus their archosaur relatives were soon to dominate life on land for many millions of years.
The first dinosaur fossils have been dated to approximately 230 million years ago, but a team of scientists working in Tanzania (Africa) have uncovered evidence of the closest relatives of the Dinosauria in much older rocks dating to the Early Triassic. This latest discovery, reported in the scientific publication “Nature” pushes back the origin of the dinosaurs by at least 10 million years.
Although the exact evolutionary lineage of the dinosaurs is still debated, it is clear that by approximately 228-230 million years ago a number of different types of dinosaur had evolved. One of the better known early dinosaurs is Herrerasaurus. Herrerasaurus (H. ishigualestensis), was a large theropod dinosaur named and described in 1988 when skull material of this dinosaur species was found. Other elements of the skeleton had been discovered in 1959, but with the skull; a more positive description of this early, meat-eater could be made.
An Illustration of the Early Carnivore Herrerasaurus
Picture credit: Everything Dinosaur