Caenogenesis

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Caenogenesis (also variously spelled cenogenesis, kainogenesis, kenogenesis) is the introduction during embryonic development of characters or structure not present in the earlier evolutionary history of the strain or species, as opposed to palingenesis.[1][2] Notable examples include the addition of the placenta in mammals.

Caenogenesis constitutes a violation to Ernst Haeckel's biogenetic law and was explained by Haeckel as adaptation to the peculiar conditions of the organism's individual development. Other authorities, such as Wilhelm His, Sr., on the contrary saw embryonic differences as precursors to adult differences.

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References[edit]

  1. ^ Clark, David L. (1962). "Paedomorphosis, Acceleration, and Caenogenesis in the Evolution of Texas Cretaceous Ammonoids". Evolution. 16 (3): 300–305. doi:10.2307/2406278. ISSN 0014-3820. JSTOR 2406278.
  2. ^ Blanco, M. J.; Alberch, P. (June 1992). "Caenogenesis, Developmental Variability, and Evolution in the Carpus and Tarsus of the Marbled Newttriturus Marmoratus". Evolution. 46 (3): 677–687. doi:10.1111/j.1558-5646.1992.tb02075.x. PMID 28568662. S2CID 36555766.

Bibliography[edit]

Gould, S.J. 1977. Ontogeny and Phylogeny. Cambridge: Harvard University Press.