Rates of Evolution

What does it mean by “rate”? How fast or slow something goes So…”Rates of Evolution” means… – How fast or slow change happens over time

Rates of Evolution Catastrophism Georges Cuvier – He believed that a natural disaster would occur, cause landforms to change and cause species to become extinct – Once that species went extinct another would come in and take its place – Did not believe species changed over time Also supported by Charles Bonnet

Rates of Evolution Gradualism – James Hutton Evolution occurs slowly and constantly over a long period of time Darwin also supported this theory

Rates of Evolution Punctuated Equilibrium – Evolution occurs in spurts – A period of change will be followed by a long period of time with little to no change at all Believed that periods of rapid change are caused by either random changes in DNA or sudden changes in the environment – Use Cambrian Explosion as support Period of geologic time, about 530 million years ago, when most of the major groups of complex animals appeared on Earth Shown by fossil record Sudden warming of Earth’s climate

Rates of Evolution Uniformitarianism Charles Lyell – Expansion of gradualism – Favored theory of geologic change – Proposed that changes occur slowly at a constant rate continuously – Impacted work of Charles Darwin