Topic summary
Gravisauria
Extracted from the Wikipedia article Sauropoda.
Classification
Gravisauria split off in the Early Jurassic, around the Pliensbachian and Toarcian, 183 million years ago, and Aquesbi thought that this was part of a much larger revolution in the fauna, which includes the disappearance of Prosauropoda, Coelophysoidea and basalThyreophora, which they attributed to a worldwide mass extinction.