Overview

Fossils were first determined to be the remains of extinct animals in the nineteenth century. This realization carried with it the concept of extinction, something that did not play a major part in the religion-dominated science of the day. As the science of geology developed, so did the understanding that, every so often, a very large percentage of species on the Earth vanished for no apparent reason. There have been at least 10 mass extinctions recorded in the fossil record in the past 600 million years. While many reasons for this have been proposed, there is only one such event for which the cause is known, that which precipitated the extinction of the dinosaurs. This catastrophic event, caused by the impact of a large body such as...