Alfred Russel Wallace and the elimination of the unfit.

ABSTRACT

The differences between Charles Darwin’s and Alfred Russel Wallace’s theories of natural selection have been discussed for many years, with particular attention to their varying thoughts on sexual selection, whether competition occurs primarily between individuals or varieties, and how human consciousness evolves. Potentially the most important difference between their respective points of view has, however, been largely overlooked. Darwin’s natural selection, later characterized as the ‘survival of the fittest,’ contains an ‘adaptation results in adaptations’ logic that some have criticized as tautological (Lewontin 1984) or even teleological (Reiss 2009). This inelegancy has been tolerated because the theory’s stated premises (i.e. the presence of a limited resource base, coupled with variation within populations and the potential for procreation to the point of superabundance) remain as unassailable now as they were originally. In a paper in the journal Complexity (Smith 2012), however, I argue that Wallace’s conceptualization, focusing on an elimination (or extermination) of the unfit driving mechanism, might represent a better vehicle for relating natural selection to other evolution-related phenomena such as mass extinction, divergence, speciation and the origins of variation itself. Wallace’s natural selection emphasizes ecological interactions. Bateson (1972) noted his use of the steam engine governor analogy as a means of describing its operation in the famous essay ‘On the tendency of varieties to depart indefinitely from the original type’ (Wallace 1858; see excerpt below), and went so far as to interpret Wallace’s thinking (see first quotation below) as the first example of cybernetic modelling. One immediate benefit of this kind of thinking is that it becomes easier to differentiate selection for domestication from ‘natural’ selection in the former, the ideal of fitness is a predetermined one and is deliberately selected for, whereas in the latter, removal is not predetermined, leaving successful adaptation a function of environmental engagement – of whatever sort. Importantly, such engagement can then be considered in independently conceived ecological and biogeographical terms, thus focusing on assembly rules and eliminating the tautological trap. Darwin, by contrast, once stated ‘It is a beautiful part of my theory, that domesticated races of organics are made by precisely same means as species – but latter far more perfectly and infinitely slower’ (Darwin 2002). Further discussion of this matter can proceed elsewhere. As a first step, however, it is essential workers at least come to grips with the idea that Wallace really did think in ‘elimination of the unfit’ terms, and consider how this framework might lead us in new directions. To that end I have compiled a set of excerpts from Wallace’s writings that should leave few doubts on that score The action of this principle is exactly like that of the centrifugal governor of the steam engine, which checks and corrects any irregularities almost before they become evident; and in like manner no unbalanced deficiency in the animal kingdom can ever reach any conspicuous magnitude, because it would make itself felt at the very first step, by rendering existence difficult and extinction almost sure soon to follow. (Wallace 1858, p 62) Natural selection . . . does not so much select special variations as exterminate the most unfavourable ones. (from a famous 1866 letter to Darwin reproduced in Marchant 1916) In the case of butterflies the argument becomes even stronger, because the fertility is so much greater, and the weeding out of the unfit takes place, to a great extent, in the egg and larvæ state. (Wallace 1877, p 405).