Ernst Heinrich Philipp August Haeckel (1834-1919), also written von Haeckel, was an eminent German biologist, naturalist, philosopher, physician, professor and artist who discovered, described and named thousands of new species, mapped a genealogical tree relating all life forms, and coined many terms in biology, including phylum, phylogeny, ecology and the kingdom Protista. Haeckel promoted and popularised Charles Darwin's work in Germany and developed the controversial recapitulation theory.