Phylogeny and ontogeny are, therefore, the two coordinated branches of morphology. Phylogeny is the developmental history [Entwickelungsgeschichte] of the abstract, genealogical individual;… — Ernst Haeckel Copy Share Image
A living organism must be studied from two distinct aspects. One of these is the causal-analytic aspect which is so fruitfully applicable… — Gavin de Beer Copy Share Image
“As long as museums and universities send out expeditions to bring to light new forms of living and extinct animals and new… — William King Gregory Copy Share Image
It is now firmly established that ontogeny does not repeat phylogeny — George Gaylord Simpson Copy Share Image
![“Phylogeny and ontogeny are, therefore, the two coordinated branches of morphology. Phylogeny is the developmental history [Entwickelungsgeschichte] of the abstract, genealogical individual; ontogeny, on the other hand, is the developmental history of the concrete, morphological individual.” quote by Ernst Haeckel](https://sms4smile.com/quotes/img-quotes/bfa/ernst-haeckel-20972_abstract_phylogeny-and-ontogeny-are-therefore-the_1640087.jpg)
