neoteny

American  

[nee-ot-n-ee] / niˈɒt n i /

noun

Biology.

1. Also called pedogenesis.  the production of offspring by an organism in its larval or juvenile form; the elimination of the adult phase of the life cycle.

2. a slowing of the rate of development with the consequent retention in adulthood of a feature or features that appeared in an earlier phase in the life cycle of ancestral individuals.

   Neoteny in the ostrich has resulted in adult birds sporting the down feathers of nestlings.

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neoteny British  

/ ˌniːəʊˈtɛnɪk, nɪˈɒtənɪ /

noun

1. the persistence of larval or fetal features in the adult form of an animal. For example, the adult axolotl, a salamander, retains larval external gills See also paedogenesis

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neoteny Scientific  

/ nē-ŏt′n-ē /

1. The retention of juvenile characteristics in the adults of a species. Humans, for example, are sometimes said to demonstrate neoteny by retaining through adulthood the relatively large head and hairlessness characteristic of very young primates. The body proportions of flightless birds, which resemble those of fetal flying birds, are also considered to be evidence of neoteny.

2. The attainment of sexual maturity by an organism still in its larval stage, seen in certain amphibians and insects. Certain species of salamanders, for instance, demonstrate neoteny as they become sexually mature but remain aquatic and do not develop legs. Neoteny sometimes occurs in response to environmental stresses such as low temperature or lack of iodine (which is essential for the thyroid gland). If environmental conditions improve, the organism can often develop into a fully mature adult form.

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Other Word Forms

• neotenic adjective
• neotenous adjective

Etymology

Origin of neoteny

1900–05; < New Latin neotēnia < Greek neo- neo- + teín ( ein ) to stretch + -ia -y ³

Example Sentences

The Mexican axolotl — a dusky amphibian with the remarkable habit of neoteny, or retaining its juvenile body type all its life — once thrived in these canals.

From New York Times • Dec. 5, 2023

It’s not unusual for domesticated animals to retain juvenile traits into adulthood—a phenomenon called neoteny that also explains, for example, why dogs look and act more like wolf cubs than adult wolves.

From Scientific American • Sep. 7, 2023

Extraordinary neoteny of synaptic spines in the human prefrontal cortex.

From Nature • Feb. 20, 2018

The idea of neoteny predates even Darwin’s On the Origin of the Species.

From Slate • Jan. 29, 2013

We have warrant for this possibility in the case of the Axolotl and in other similar cases of neoteny.

From Darwin and Modern Science by Seward, A. C. (Albert Charles)