Neoteny (/niˈɒtəni/), also called juvenilization, is the delaying or slowing of the physiological (or somatic) development of an organism, typically an animal. Neoteny is found in fish (compare to frogs) and modern humans (compare to other primates). In progenesis (also called paedogenesis), sexual development is accelerated.

Both neoteny and progenesis result in paedomorphism (or paedomorphosis), a type of heterochrony. It is the retention in adults of traits previously seen only in the young. Such retention is important in evolutionary biology, domestication and evolutionary developmental biology.

Some authors define paedomorphism as the retention of larval traits, as seen in salamanders.

 

Note:   The above text is excerpted from the Wikipedia article Neoteny, which has been released under the GNU Free Documentation License.