Scientists hatch new theory on extinction

The eggs of nonavian dinosaurs took three to six months to hatch, a long incubation period that could help explain dinosaurs' mass extinction 65 million years ago, according to new research.

Findings published on Monday in the Proceedings of the National Academy of Sciences show that nonavian dinosaur incubation mirrored that of reptiles - a prolonged time before hatching that could have impacted dinosaurs' ability to compete with other animal populations that were breeding faster.

Many researchers previously assumed both nonavian and avian dinosaurs' incubation length was more in line with today's birds, whose eggs hatch in 11 to 85 days.