Philosophy of Selection (Natural, Sexual and Drift)

Four main ingredients are necessary for the recipe of natural selection: a common demanding and competitive environment; individual, spontaneous variation; inheritance of part of this variation; a sufficient time frame. The result is a differential survival and reproduction of varying individuals, multiplied over generations: self-reproducing lineages of organisms change over time. As a statistical process with probabilistic outcomes, natural selection can be explained without using somehow misleading terms such as “adaptation” and “chance”. The selective process is an experienced fact in nature and an explanatory pattern that could be generalized in different forms (like sexual selection, kin selection and so on). Despite its strong explanatory power, natural selection is a constrained process and is not self-sufficient: it is the pivot within a plurality of complementary and alternative explanatory patterns, the most important of which is the genetic drift.