Neoteny (pronounced
/ni?'?t?ni?/) is the retention, by adults in a species, of traits previously seen only in juveniles (
pedomorphosis/paedomorphosis), and is a subject studied in the field of
developmental biology. In neoteny, the
physiological (or
somatic) development of an animal or organism is slowed or delayed. Ultimately this process results in the retention, in the adults of a
species, of juvenile physical characteristics well into maturity. The
English word
neoteny is borrowed from the
German Neotenie, the latter constructed from the
Greek ???? (young) and
te??e?? (tend to). The standard
adjectival form is "neotenous", although "neotenic" is often used.
In vertebrate biology, neoteny is most easily identified when sexually mature, completely viable juveniles or larvae are found.
Specific individual traits that differ in descendant organisms, when compared to ancestors, are sometimes called neotenies; humans, for example, appear to have several neotenies in comparison to chimpanzees.
Neoteny plays a role in evolution, as a means by which, over generations, a species can undergo a significant physical change. In such cases, a species’ neotenous form becomes its “normal” mature form, no longer dependent upon environmental triggers to inhibit maturity. The mechanism for this could be a mutation in or interactions between genes involved in maturation, changing their function to impede this process.
