Plant biomass could have been produced in greater quantities. Plant communities at that time were changing to larger, taller plants that would have favored larger, taller herbivores. No such bone patterns appear in dinosaur bones. Bakker suggests than since dinosaurs lack these markings, this emphasizes their uniqueness among the reptiles. A. New dinosaur bones discovered are unlike either modern reptiles or mammals.
Young crocodiles have bones similar to some dinosaur bones.
During the time of dinosaurs, the types of plants present included primarily conifers and cycads and not the angiosperms used by modern grazing animals. Human Over Hunting probably played a major role.