A longer incubation time means non-avian dinosaurs were definitely at a disadvantage when an asteroid or a comet slammed into our planet 65 million years ago. Since it took much longer for them to reproduce and to replace the population that perished in the impact, their incubation period could be one of the factors that led to their extinction. Meanwhile, the birds that already existed in that era that didn't need the same amount of time to hatch thrived and led to the birds we know today.

That said, their long incubation period is only one of the factors why they died out. Lead researcher Gregory M. Erickson of Florida State University said: