What is Neoteny

Neoteny:

The occurance of both adult and juveline characters together in an organism is called as Neoteny.
   This is seen in Amphibians. Example is Axolotol larva of Ambylostoma.
  Neoteny can also be defined as the loss of sexual maturity in the organisms and retain of larval characters along with adult characters.

Why Neoteny is observed in an organisms?

Neoteny occurs due to lack of thyroid stimulating harmone which stimulates thyroid to produce thyroxine.
The hypothalamus of the brain fails to stimulate the thyroid gland to produce growth harmone which stops the metamorphosis.

Axolotol of Ambylostoma can again get metamorphose by giving injections of Iodine or by giving shocks of Thyroxine harmone.

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