User:Manudouz/sandbox/Reversion (biology)

Reversion, or sometimes reversal, is, in the field of the evolutionary biology, the return of a character state to an ancestral state manifested by a gene mutation in the DNA making it possible to recover the functions of a gene after that he lost them as a result of a first mutation. This phenomenon allowed biologists to determine mathematical laws of reversion by convergent atavism.

The discovery of the reversion calls into question Dollo's law, which, stated by a nineteenth-century Franco-Belgian paleontologist, posed the irreversible nature of evolution.

"Homoplasy is similarity that is the result not of simple ancestry, but of either reversal to an ancestral trait in a lineage or of independent evolution (convergence, similarity resulting from different developmental genetic mechanisms; or parallelism, similarity resulting from the same developmental genetic mechanisms)".

At the morphological level

 * Frogs: Gastrotheca guentheri.
 * Snails.