Dinosaur Lived in Herds Socialised nearly 200 million Years Ago

At a location in Argentina, South America, palaeontologists discovered the earliest evidence of Dinosaur living in herds and socialising by age groups. More than 100 fossilised eggs and skeletons of 80 different Dinosaur, ranging from embryos to fully grown adults, were discovered within trenches dug by the animals themselves, revealing socially coherent groupings based on age and resting behaviour. The findings were published in the journal Scientific Reports this week.

While some Dinosaur species were known to travel in herds, the behaviour is estimated to have begun just approximately 150 million years ago. The new fossils, belonging to the herbivore Mussaurus patagonicus, date back to 193 million years ago, indicating that herding behaviour was apparent in the animals much earlier than thought.

Today’s reptilian, non-avian descendants of Dinosaur do not move or live in herds, whereas avian descendants, such as birds, do. According to the researchers, social age groups like this would have lasted throughout an individual’s lifetime, and herding behaviour is what allowed some of these species to survive huge extinction events and become dominant in terrestrial ecosystems.The fossils were discovered in the Laguna Colorada Formation, in the Santa Cruz Province of Argentina. The site is rich in Dinosaur fossils and has been the source for many discoveries, including the discovery of the species M. patagonicus. The site covered an area of approximately one square kilometre.

Nearly 11 individuals belonging to this species that was discovered earlier, the new expedition provided 69 new specimens with skeletons of individuals of various ages. There were eight small individuals, described as newborns as they are just bigger than the size of the embryos inside unhatched eggs. As they were all similarly sized, scientists think they hatched at the same time.