how did the theory of evolution start
In the early 19th century Jean-Baptiste Lamarck (1744 â 1829) proposed his theory of the transmutation of species, the first fully formed theory of evolution. In 1858 Charles Darwin and Alfred Russel Wallace published a new evolutionary theory, explained in detail in Darwin's On the Origin of Species (1859). Unlike Lamarck, Darwin proposed common descent and a branching tree of life, meaning that two very different species could share a common ancestor.