About 1800 French biologist Jean Baptiste de Lamarck says organisms change by adapting to their environment. 1817 French naturalist Georges Cuvier proposes that floods and other catastrophes divide the geologic record into distinct eras where different kinds of organisms lived. Organisms that are better suited to the environment are more likely to survive and reproduce, forcing species to change, or evolve.
Fossil evidence shows gradual change and development of organisms in both plant and animal realms.
Pollster George Gallup finds that about 50 percent of the U.S. population believes in strict creationism. 1980s to present Analysis of DNA and RNA is used to map the tree of life. Resurgence of creationism among religious fundamentalists renews pressure on biology teachers. Kansas school board removes teaching of evolution and cosmology from required high-school science curriculum and testing. The Ancient Debate .