The initial stages of human embryogenesis
Parts of a human embryo
This article concerns ontogeny in biology. Not to be confused with the philosophical concept ontology, or the medical terms oncology or odontology.

Ontogeny (also ontogenesis or phylogeny, which refers to the evolutionary history of a species. In practice, writers on evolution often speak of species as "developing" traits or characteristics. This can be misleading. While developmental (i.e., ontogenetic) processes can influence subsequent evolutionary (e.g., phylogenetic) processes[1] (see evolutionary developmental biology), individual organisms develop (ontogeny), while species evolve (phylogeny).

Ontogeny, embryology and developmental biology are closely related studies and the terms are sometimes used interchangeably. Recently (2003), the term ontogeny has been used in

  • Media related to at Wikimedia Commons
  • The dictionary definition of at Wiktionary

External links

  1. ^ Gould, S.J. (1977). Ontogeny and Phylogeny. Cambridge, Massachusetts: The Belknap Press of Harvard University Press
  2. ^ Thiery, Jean Paul (1 December 2003). "Epithelial–mesenchymal transitions in development and pathologies". Current Opinion in Cell Biology 15 (6): 740–746.  
  3. ^ See -geny in the Oxford English Dictionary, second edition, 1989; online version March 2011, accessed 9 May 2011. Earlier version first published in New English Dictionary, 1898.
  4. ^   See page 411.
  5. ^ Pough, F. H. 1978. Ontogenetic changes in endurance in water snakes (Natrix sipedon): Physiological correlates and ecological consequences. Copeia 1978:69-75.
  6. ^ Garland, Jr., T. 1985. Ontogenetic and individual variation in size, shape and speed in the Australian agamid lizard Amphibolurus nuchalis. Journal of Zoology 207:425–439.
  7. ^ Garland, Jr., T., and P. L. Else. 1987. Seasonal, sexual, and individual variation in endurance and activity metabolism in lizards. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 252:R439–R449.

Notes and references

See also

Most organisms undergo dramatic changes in shape as they grow and mature. Even "reptiles" (e.g., crocodilians, turtles, snakes,[5] lizards[6]), in which the offspring are often viewed as miniature adults, show a variety of ontogenetic changes in morphology and physiology.[7]

Ontogenetic allometry

A seminal paper named ontogeny as one of the four primary questions of biology, along with Huxley's three others: causation, survival value and evolution.[4] Tinbergen emphasized that the change of behavioral machinery during development was distinct from the change in behavior during development. "We can conclude that the thrush itself, i.e. its behavioral machinery, has changed only if the behavior change occurred while the environment was held constant...When we turn from description to causal analysis, and ask in what way the observed change in behavior machinery has been brought about, the natural first step is to try and distinguish between environmental influences and those within the animal...In ontogeny the conclusion that a certain change is internally controlled (is "innate") is reached by elimination. " (p. 424) Tinbergen was concerned that the elimination of environmental factors is difficult to establish, and the use of the word "innate" often misleading.

Nature and nurture

The word ontogeny comes from the Greek ὄν, on (gen. ὄντος, ontos), i.e. "being; that which is", which is the present participle of the verb εἰμί, eimi, i.e. "to be, I am", and from the suffix -geny from the Greek -γένεια -geneia, which expresses the concept of "mode of production".[3]



  • Etymology 1
  • Nature and nurture 2
  • Ontogenetic allometry 3
  • See also 4
  • Notes and references 5
  • External links 6

Ontogeny is a useful field of study in many disciplines, including but not limited to developmental biology, developmental psychology, developmental cognitive neuroscience, and developmental psychobiology.