LiveScience.com – Dinosaurs are often seen as unlucky, having been wiped out by an asteroid. But they dominated Earth for more than 160 million years, evolving into a wild array of body types and sizes suited for many different ecological niches.

Scientists previously thought that it was this evolutionary diversity that enabled the dinosaurs’ reign, allowing them to out-compete similar groups of reptiles, but a new study, detailed in the Sept. 11 issue of the journal Science, shows that it was really just a matter of luck. …