There has been a lengthy discussion about why dinosaurs were so successful. Say dinosaur, and most people think of a great flesh eater like the Tyrannosaurus Rex, but herbivores have become more popular and more successful.
A new study from the University of Bristol, led by Eddie Strickson, has provided clear evidence of how herbivorous dinosaurs evolved. Numerous dinosaurs have been found in North America, but no tyrannosaur skeletons have been found. Scientists wondered what they ate and how the herbivores survived.
Eddie Strickson said: “The herbivores showed four evolutionary spikes: one in the middle of the Jurassic and the other three clusters about 80 million years ago at the end of the Cretaceous. This is innovation in jaws and increased efficiency."
Plants develop rapidly during the Mesozoic, with the rise of cycads, conifers, and especially angiosperms or flowering plants in the Cretaceous. However, the evolution of the dinosaur's jaw and teeth show no reaction to these changes in flora.
Dr. Albert Prieto-Marquez, a researcher at the School of Earth Sciences who was one of the leaders of the study, said: "Some of the very successful platypus hadrosaurs from the late Cretaceous period may have ate flowering plants, and coprolites were especially studied."
Over 150 million years, many hundreds of dinosaurs have come and gone, but eventually they all became extinct 66 million years ago. The new work helps confirm the recently published and controversial claims that most dinosaurs were already in decline 40 million years before the meteorite hit and finished them off.
Ruban Oleg
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