approximately how long ago did our current era begin
Dinosaurs lived throughout the Mesozoic Era, which began 245 million years ago and lasted for 180 million years. It is sometimes called the Age of the Reptiles. The era is divided into three periods.45 to 208 million years ago. 1  During the Triassic period, all land on Earth existed as one enormous mass. 2  It was called Pangaea. 3  The supercontinent slowly began to break up during the Triassic Period.