Early dinosaurs may have lived in social herds as early as 193 million years ago

Scientists believe they have found the earliest evidence for complex herd behavior in dinosaurs. Researchers say Mussaurus patagonicus may have lived in herds some 193 million years ago -- 40 million years earlier than other records of dinosaur herding.

source https://www.sciencedaily.com/releases/2021/10/211021120921.htm