Haeck·el (hĕkəl), Ernst Heinrich 1834-1919.
German philosopher and naturalist who supported Darwin's theory, mapped a genealogical tree relating all animal life, and developed the maxim "Ontogeny recapitulates phylogeny."
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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