Although most dinosaurs went extinct 65 million years ago, one dinosaur lineage survived and lives on today as a major evolutionary success story — the birds. A study that has ‘weighed’ hundreds of dinosaurs suggests that shrinking their bodies may have helped the group that became birds to continue exploiting new ecological niches throughout their evolution, and become hugely successful today.

Dinosaur phylogeny showing nodes with exceptional rates of body size evolution.
Credit: Benson RBJ, Campione NE, Carrano MT, Mannion PD, Sullivan C, et al. (2014) Rates of Dinosaur Body Mass Evolution Indicate 170 Million Years of Sustained Ecological Innovation on the Avian Stem Lineage. PLoS Biol 12(5): e1001853. doi:10.1371/journal.pbio.1001853

An international team, led by scientists at Oxford University and the Royal Ontario Museum, estimated the body mass of 426 dinosaur species based on the thickness of their leg bones. The team found that dinosaurs showed rapid rates of body…