Dinosaur Extinction

65 million years ago, all the dinosaurs, many sea creatures, and some mammals on Earth abruptly went extinct, changing Earth forever. This mass extinction is called the Cretaceous-Tertiary (KT) Boundary. There is a range of theories to explain why this took place, including a health downfall, volcanism, and various other reasons, but the most supported is an asteroid impact that devastated Earth.

One theory behind dinosaur extinction is an overall health decline in dinosaurs. This theory is supported by the combination of smaller theories, such as competition, stress, and disease. Competing with mammals for various resources necessary to life would have caused starvation among the dinosaurs. The existence of mammals themselves threatened dinosaurs by causing overpopulation. The starvation and overpopulation caused stress in the dinosaurs. The stress led to low immunity and foreign dinosaurs brought diseases they were now easy susceptible to. The stress, diseases, and competition caused overall poor health in dinosaurs, and the species declined until they were extinct.

This theory of declining health is not very popular. There are a few pieces of supporting evidence, though. Scientist have found that the dinosaurs had been laying thinner eggshells, which could have been caused by stress. Plate tectonics explain easier travel for dinosaurs, and therefore, disease. The invalidating points of this theory are stronger, though. It does not use much evidence found in the KT boundary. Also, it does not explain or take into account the known atmospheric and climate changes at the time. This idea of health decline is now believed as part of a small decline before the actual event of mass extinction.

A more recently popularized theory of dinosaur extinction is volcanism. This concept states that between 63 and 67 million years ago, there were gigantic volcanic explosions that created what we now know as the Deccan Traps lava bed in India. The explosions triggered...