Ernst Haeckel (1834-1919)
E.H. 헤켈은 프로티스타계를 제창. 1869년에 생태학이라는 용어를 제안. Phylum, phylogeny등의 용어도 최초로 정의했다. 다윈의 종의 기원을 읽고 의사직을 버리고 1859년부터 생물학을 하게 된다.
헤켈의 유명한 인용문:
"I established the opposite view, that this history of the embryo (ontogeny) must be completed by a second, equally valuable, and closely connected branch of thought - the history of race (phylogeny). Both of these branches of evolutionary science, are, in my opinion, in the closest causal connection; this arises from the reciprocal action of the laws of heredity and adaptation... 'ontogenesis is a brief and rapid recapitulation of phylogenesis, determined by the physiological functions of heredity (generation) and adaptation (maintenance).'"Haeckel, E. 1899. Riddle of the Universe at the Close of the Nineteenth Century.