Catastrophism is a geological and biological theory that suggests the Earth has been shaped by a series of sudden, short-lived, and catastrophic events, such as volcanic eruptions or asteroid impacts, rather than gradual processes. This concept emerged as an important counterpoint to uniformitarianism, which posits that the same natural processes observed today have been consistent over time. Understanding catastrophism provides insight into how evolutionary theory can be influenced by these dramatic events, leading to mass extinctions and significant changes in the diversity of life on Earth.