As argued by G. C. Williams it is important to distinguish adaptations from "effects" : an effect of being an apple is to provide food for insect larvae or humans; food is an effect of an apple's phenotype (good resources); apple farming is and effect of apples' good taste and nutritional value (apples did not evolve to solve the problem of providing work for apple farmers); the cryptic coloration of a katydid is not for the purpose of demonstrating adaptation in evolution lectures; demonstration is an effect of the striking morphology. To reiterate: we identify traits as adaptations only when they evolved for the solutions of a specific problem (function/purpose). Selection is myopic : evolutionary trends are clear and presumably adaptive; some of these lead to intensification other trends lead to diminution of characters. Examples: Elaborate secondary sexual characteristics : increased horns, weapons in males displaying for females; winglessness in insects: fleas adapted to reaching scalp/skin in
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