Ernst Haeckel

Ernst Heinrich Philipp August Haeckel was a German zoologist, naturalist, eugenicist, philosopher, physician, professor, marine biologist, 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 ecology, phylum, phylogeny, and Protista. Haeckel promoted and popularised Charles Darwin's work in Germany and developed the influential but no longer widely held recapitulation theory claiming that an individual organism's biological development, or ontogeny, parallels and summarises its species' evolutionary development, or phylogeny.
The published artwork of Haeckel includes over 100 detailed, multi-colour illustrations of animals and sea creatures, collected in his Kunstformen der Natur, a book which would go on to influence the Art Nouveau artistic movement. As a philosopher, Ernst Haeckel wrote Die Welträthsel, the genesis for the term "world riddle"; and Freedom in Science and Teaching to support teaching evolution.
Haeckel was also a promoter of scientific racism and embraced the idea of Social Darwinism.