Ontogeny

The initial stages of human embryogenesis

Ontogeny (also ontogenesis or morphogenesis) is the origin and the development of an organism – for example: from the fertilized egg to mature form. It covers in essence, the study of an organism's lifespan. The word "ontogeny" comes from the Greek ὄντος, ontos, present participle genitive singular neuter of εἶναι, "to be"; and from the suffix -geny, which expresses the concept of "mode of production".^[1] In more general terms, ontogeny is defined as the history of structural change in a unity, which can be a cell, an organism, or a society of organisms, without the loss of the organization which allows that unity to exist.^[2] More recently^[when?], the term ontogeny has been used in cell biology to describe the development of various cell types within an organism.

Ontogeny comprises a field of study in disciplines such as developmental biology, developmental psychology, developmental cognitive neuroscience, and developmental psychobiology.

Within biology, ontogeny pertains to the developmental history of an organism within its own lifetime, as distinct from phylogeny, which refers to the evolutionary history of species. In practice, writers on evolution often speak of species as "developing" traits or characteristics. This can be misleading. While developmental or ontogenetic processes can influence subsequent evolutionary or phylogenetic processes^[3] (see evolutionary developmental biology), individual organisms develop (ontogeny), while species evolve (phylogeny).

See also

• Recapitulation theory, the idea that ontogeny recapitulates phylogeny
• Organogenesis

Notes and references

1. ^ See -geny in the Oxford English Dictionary, second edition, 1989; online version March 2011, accessed 09 May 2011. Earlier version first published in New English Dictionary, 1898.
2. ^ Maturana, H. R., Varela F. J. (1987). The Tree of Knowledge: The Biological Roots of Human Understanding. Boston: Shambhala Publications Inc., page 74
3. ^ Gould, S.J. (1977). Ontogeny and Phylogeny. Cambridge, Massachusetts: The Belknap Press of Harvard University Press

External links