Postadaptation

evolutionary changes of organisms that improve a species’ adaptation to an already familiar habitat or that improve a function of an organ.

Postadaptation is contrasted to preadaptation, which is a chance side effect of postadaptation and which prepares an organ for new functions or an organism for adaptation to new environmental conditions. Thus, preadaptation of an organism to a new environment or of an organ to a new function is based on post-adaptation to the previous environment or to the previous function of the organ.

Both postadaptation and preadaptation are controlled by the process of natural selection; postadaptation is its immediate result, while preadaptation is an indirect and chance consequence.