"descended from" is kind of a common misconception about evolution. Birds and Dinosaurs have common ancestors. Earlier researchers thought they were closely re

"descended from" is kind of a common misconception about evolution. Birds and Dinosaurs have common ancestors. Earlier researchers thought they were closely related to reptiles, but more recent research has shown they have a lot more in common with birds. It's still somewhat of a mystery as to why dinosaurs went extincted. A very large asteroid did hit the Earth at the end of the Cretaceous. But there was a lot of other thing happening on Earth at that time. Pangea was breaking up and major waterways/oceans were opening up at that time, so there was likely major climate changes occurring, incearse Volcanism, etc..