USA HISTORY

Detailed explanation-1: -The theory of evolution is a shortened form of the term “theory of evolution by natural selection, ” which was proposed by Charles Darwin and Alfred Russel Wallace in the nineteenth century.

Detailed explanation-2: -In fact, we may distinguish five theories that Darwin combined: evolution as such, common descent, gradualism, multiplication of species, and natural selection.

Detailed explanation-3: -In the early 19th century prior to Darwinism, Jean-Baptiste Lamarck (1744–1829) proposed his theory of the transmutation of species, the first fully formed theory of evolution.

Detailed explanation-4: -Over time, an advantage spreads throughout a species; in turn, the species is more likely to endure and reproduce. Thus, over the course of many generations, subtle changes occur and accumulate, eventually morphing into bigger changes and, possibly, even a new species.

Detailed explanation-5: -According to Lamarck, organisms altered their behavior in response to environmental change. Their changed behavior, in turn, modified their organs, and their offspring inherited those “improved” structures.