Paedomorphosis

Paedomorphosis is one of the mechanisms of developmental heterochrony, i.e. changes in the speed and duration of development of organisms. The phenomenon results in juvenile features in adults.

Two types of paedomorphosis are recognised: hypomorphism and neoteny.

The axolotl (Ambystoma mexicanum) is the most widely known example of neotenic paedomorphism. Here the gills (in red) are seen which the adult has preserved from its larval stage. © Arne Kuilman CC by-nc 2.0