Sunday, October 18, 2015

But for Adaptations: Inverting the Assumption

Evolution theorists seem to assume that a successful creature marches into its environment equipped with an armamentarium of adaptations. Such a creature inherits its adaptations from its parents. The adaptations bestow fitness upon the creature. This fitness in turn bestows reproductive success, at least relative to that of the creature’s local conspecific peers/competitors. The reproductive success conveys the creature’s DNA to its progeny, who thereby themselves enjoy an armamentarium of adaptations similar to that of their parents (unless a changing environment turns those adaptations into neutral or even deleterious traits).

Point is, reproductive success is taken to be an effect caused by adaptations.

This position, stated otherwise, contends that, but for the adaptations, the creature would experience reproductive failure relative to its local conspecific peers.

But we can invert the assumption: Maybe the default position ought to be that organisms normally enjoy reproductive success, absent any factors, endogenous or exogenous, that undermine that success.

Organisms are integrated wholes, adapted, but not possessing adaptations. Organicism suggests that a creature doesn’t possess adaptations any more than an atom possesses protons. A proton, or a fused bundle of them, just is an atom. Atoms typically come decked out with other particles, the neutrons and electrons, but no protons, no atoms.

Similarly, a creature does not possess anatomical and physiological adaptations. It simply is its anatomy and its physiology. It comprises them, and they compose it. No physiology or anatomy, no creature.

In the case of a bird, for example, wings might be called an adaptation, but lay a couple on the ground and not much will happen. Lay a wingless bird on the ground and not much will happen beyond the suffering and demise of the bird. Whatever gets designated as an adaptation contributes no more to the rest of the creature than the rest contributes to it. Without the wings there just is no viable “rest of the bird,” that happens not to own wings. For evolutionary purposes, there just is no critter.

So, does the presence of adaptations enable or the absence of lethal/sterilizing circumstances allow a creature to live and reproduce?

In any case, if evolutionary theorists insist on retaining the notion of adaptation, then they should clarify the term as designating not things that an organism has but the whole organism. Nature doesn’t select traits, thereby turning them into adaptations, and then assemble the traits into adapted organisms. Nature selects whole developmental physiologies and the resulting creatures’ characteristic behaviors. That’s all it has to work with.

A simple way to operationalize natural selection would be to count progeny, or more specifically, to count viable, fertile progeny. If this is the understanding—that natural selection means relative reproductive success in the same way that hunger means two or more days without food, that is, if natural selection is operationalized in terms of empirical observations and statistical thresholds—then the term would have a noncontroversial conventionalized usage (with potentially other thresholds established to define genetic drift, and maybe others bad luck or acts of God). But if “natural selection” denotes a process that cannot be operationalized in this or some other way, then the concept of natural selection, whatever merits it might possess, is not a scientific concept, but an example of the nominal fallacy, in which the christening of something with a name (e.g., natural selection) mistakenly is taken to be an explaining of the thing (e.g., evolutionary outcomes).

Rational thinkers of the world unite. You have nothing to lose but your adaptations.

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