Question

What is neoteny?

Answer 1

Neoteny occurs when an organism achieves adulthood while retaining all of its juvenile traits. For example, becoming sexually viable while still in the larvae stage or retaining gills as an adult are both examples.

Complete solution:
Neoteny is the occurrence of traits in adults in a species that were previously only seen in juvenile forms (pedomorphosis/paedomorphosis), and it is a topic studied in developmental biology. The physiological (or somatic) growth of an animal or creature is retarded or postponed in neoteny. Finally, this process leads to the retention of juvenile morphological characteristics in mature adults of a species. In vertebrate biology, neoteny is most easily diagnosed when sexually developed, completely alive juveniles or larvae are found.
Ambystoma axolotl larva is the best example. It is a watery environment, has gills and produces gonads. It produces eggs and grows to be rather huge. Ambystoma, on the other hand, is land-based and lacks gills. The axolotl was once thought to be a different genera, but with the injection of thyroxine, the axolotl lost its gills and developed lungs. It grew up and became an adult. Axolotl metamorphosis can be triggered by lowering the water level.

Note:
Proteus and Necturus are neotenous all the time. They kept their larval characteristics and reproduced sexually like adults.