The End of Dinosaurs

Theories About Dinosaur Extinction

What is the “disease theory” of dinosaur extinction?

The “disease theory” of dinosaur extinction (which falls under the theory of gradualism) states that dinosaurs eventually died out because of disease. Some say biological changes, brought about by changes in their evolution, made the animals less competitive with other organisms, including mammals that had just started appearing. Others say a major disease—anything from rickets to constipation—wiped out the dinosaurs, with some dinosaur bones definitely showing signs of these diseases over time. Another idea is that overpopulation led to the spread of major diseases among certain species of dinosaurs, and eventually to them all.


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