Lamarckism

Theory of evolution, now discredited, advocated during the early 19th century by French naturalist Jean Baptiste Lamarck. Lamarckism is the theory that acquired characteristics, such as the increased body mass of an athlete, were inherited. It differs from the Darwinian theory of evolution.

According to Lamarck, organisms have an urge to ‘improve’ rather than being shaped by natural selection acting on random variations. Later, Lamarckism just came to mean a belief in the inheritance of acquired characteristics–a now discarded opinion shared by most biologists before the discovery of genetics.