Dinosaurs displayed a fast growth rate from the very beginning

Dinosaurs displayed a fast growth rate from the very beginning

An illustration of the head of the early dinosaur Herrerasaurus ischigualastensis. Jordan Harris/Handout via REUTERS

One of the traits that helped make the dinosaurs such an evolutionary success story - thriving for 165 million years - was their fast growth rate, from massive meat-eaters like Tyrannosaurus to immense plant-eaters like Argentinosaurus.But when did this characteristic first appear? A new study indicates it was present in the earliest dinosaurs, as revealed by microscopic features in bone fossils from Argentina that showed that they exhibited growth rates on par with those of today's mammals and birds.Rapid growth offers numerous advantages."Growing quickly allows organisms to escape the risky business of being small for a long part of their life history. It also allows them more time to reproduce throughout their lifespan, which imparts a measure of evolutionary fitness, generation by generation," said paleontologist Kristi Curry Rogers of Macalester College in Minnesota, lead author of the study published this month in the journal PLOS ONE.The researchers examined patterns preserved within the bones of dinosaurs and some of their cousins that inhabited northwestern Argentina between about 231 and 229 million years ago."The organization of minute bone mineral crystals and proteins, along with blood vessels