Lee Harrington 30 minutes ago

First point is for the copy writer:- They are not lies; nobody qualified ever suggested that gravity was different then and more oxygen was a serious hypothesis for the large sizes seen, subsequently falsified by the new hypothesis that there was probably less oxygen and that the dinosaurs probably had bird like lungs. Second point:- The birds did not evolve from "the" dinosaurs. They evolved from a specific group of dinosaurs called Theropods. For my money, this still does not explain the size thing as there were many species of small dinosaurs and the efficient bird like lungs would have been negated by the low oxygen atmosphere. A final couple of points:- Fast growth is nothing special. Cattle, for instance, grow from freshly born to, more or less, fully grown in a single year; The video maker does not seem to be aware that after the dinosaurs came a very long era, of massively huge mammals, of numerous different types, who definitely did not have bird like lungs.