The oxygen levels had far more to do with it than food sources. High oxygen levels allows the body digest food better/faster, muscles to function at higher efficiencies, etc. A multitude of reasons stem from the high oxygen levels. The air was composed of more carbon dioxide and oxygen at the time, which also allowed large pterasaurs to exist thanks to the denser air. Denser air = more lift from each flap of their wings.PopInPicsPresents wrote:wataru wrote:Dinosaur size = Abundance of food.
If the planet-eaters die out, meat eaters wouldnt have the proteins to grow. If they survived to mating age, over generations, they'd grow smaller. The lack of protein (food) though would negate brain growth and intelligence.
I believe the amount of oxygen in the air also contributes to size. A lack of oxygen would cause the animals to become smaller.
OT: Terrible drivers.