Ernst Haeckel. Coloured artwork of the German zoo- logist and evolutionist Ernst Haeckel (1834-1919). Haeckel was an ardent supporter of Charles Darwin and left medicine in order to study comparative anatomy. He was the first to attempt a geneal- ogical tree of all animals and to distinguish between unicellular (protozoan) and multicellular (metazoan) organisms. He proposed the now discredited view that the development of an embryo illustrates the evolution of its species. He also coined the terms ontogeny, phylogeny and ecology. He developed a philosophy of ethics based on evolution and misused the concept of natural selection to champion German nationalism.