Jean-Baptiste Lamarck is known for which of the following theories?

Jean-Baptiste Lamarck is renowned for his theory of the inheritance of acquired traits, often referred to as Lamarckism. This theory posits that organisms can pass on characteristics acquired during their lifetime to their offspring. For example, Lamarck suggested that if a parent organism developed a trait through use or disuse—such as a giraffe stretching its neck to reach higher leaves—then this trait could be inherited by its young. This idea was a precursor to modern evolutionary theory, despite being largely supplanted by Charles Darwin's theory of natural selection, which provides a different mechanism for evolution based on variation, competition, and differential survival rather than the inheritance of traits acquired during an organism's life.

In contrast, survival of the fittest is a phrase often associated with Darwin's theory and refers to the reproductive success of those individuals best suited to their environment. Natural selection, another concept attributed to Darwin, describes the process by which environmental pressures lead to the survival of individuals with advantageous traits. Catastrophism, a concept in geology and paleontology, suggests that the Earth has been shaped by a series of sudden, short-lived, and high-impact events, and it is not directly related to Lamarckian evolution.