Birds may owe their success to the shrinking bodies of their dinosaur ancestors.
An international team, led by paleontologist Roger Benson from the University of Oxford, measured leg bone thickness to estimate the weights of 426 dinosaur species. They used these estimates to chart body size changes over evolutionary time.
While most dinosaur groups were very slow to evolve new body forms, the lineage that eventually became birds showed rapid body size evolution sustained over 170 million years.
The researchers suggest that evolving smaller sizes allowed this lineage to exploit new ecological niches, which may help explain the success of modern-day birds.
Read more at University of Oxford