Cheating Darwin? The Ethics of Sexual Selection

Cheating Darwin? The Ethics of Sexual Selection

In a recent article titled “Cheating Darwin: The Genetic and Ethical Implications of Vanity and Cosmetic Plastic Surgery” in the July issue of the Journal of Evolution and Technology, Kristi Scott considers the potential evolutionary harms of cosmetic plastic surgery and other beauty-related enhancements. Her ‘worry’ is that individuals who have undergone cosmetic surgery and other significant ontogenetic aesthetic enhancements will not disclose this fact to their potential mates, who will then make procreation decisions based on misleading information.

The information is misleading because, according to Scott, the relevant attractive features are not actually coded for in the enhanced person’s genome. Clearly, Scott’s argument cannot be that people tend to make deliberate mating decisions based on the complex mapping of phenotypes onto genotypes. To the contrary, given that people have surprisingly limited conscious access to the morphological and behavioral features that drive their sexual attraction and repulsion to others (see Jared Diamond’s (1997) book Why is Sex Fun?), it is highly implausible that mating decisions are frequently if ever determined by beliefs about the complex causal relationship between attractive phenotypic traits and their underlying genetic basis.

Hence, the concern that one party to the procreative contract is being intentionally or knowingly misled as to a material term of the agreement is simply misplaced. Anecdotally at least, it seems that when it comes to base-level physical attraction, people do not tend to lose interest if it is revealed that some apparent ‘hottie’ has been ‘augmented’ through either cosmetic surgery or cosmetics more broadly. And this is to be expected, since sexual attraction (described at the personal level as “chemistry”) is governed in no small part by cognitive faculties which, like those responsible for the persistence of the Muller-Lyer illusion, remain largely impenetrable to and unaffected by higher-level reasoning processes. Of course, if one enters into a partnership (sexual or otherwise) by lying about a crucial premise on which that partnership is based, then obvious ethical concerns arise; but this applies to any sort of relationship, whether it is based on a promise to be faithful or that one’s nose has not been surgically tweaked. Nevertheless, I think it is safe to presume that relationships conditioned on the latter proposition (or the equivalent) are exceedingly rare, and I would not go so far as to require (morally or legally), as Scott does, that ontogenetically enhanced individuals should give a visual reference of their pre-enhanced state to their potentially ‘deceived’ mate so that the latter is made fully aware of the genetic predisposition that he or she may be passing on to progeny.

But let us move on to the real specter of harm that Scott decries: namely, the ‘genetic’ or ‘evolutionary’ harms associated with plastic surgery. She states as follows: “Without the availability of [cosmetic plastic surgery], the attribute may have been hindered in procreation, and been naturally weeded out, but with CPS it is given a potential chance to continue on, despite its perceived lack of desirability.” (Note that Scott’s argument applies to all modifications that are not germ-line enhancements, since the latter are not (typically) transmitted to subsequent generations thanks to the sequestering of the gametes from environmental influence). As Darwin appreciated long ago, few decisions can be as biologically momentous in sexually reproducing animals as the decision to mate with a conspecific. But Darwin was careful to distinguish sexual from natural selection, precisely because unlike ordinary adaptations, the traits that seem to attract mates are frequently not connected in any obvious way to fitness—indeed they often appear to be ecologically deleterious. Scott’s notion that mate selection in contemporary humans will tend to weed out traits that are harmful from the standpoint of the human good is problematic, for several reasons. First, simply because something is adaptive for one or both sexes does not mean that it makes people better off, since biological fitness is not equivalent to the human good. The increased disposition toward infanticide of stepchildren (as compared to biological children) is probably an adaptation in many male mammals, humans included, but clearly it is not a morally desirable trait. Moreover, runaway sexual selection can have an evolutionary ratcheting effect that makes everybody worse off. For example, in negative frequency-dependent sexual selection, the attractiveness of a given trait of the opposite sex turns on how common the trait is (so-called ‘rare male advantage’). If the attractive trait is, say, female genital mutilation or foot-binding which increase the chances in certain societies of landing a well-resourced husband, these traits will increase in frequency until they are widespread, despite significantly reducing the quality of life for all involved. Once they are widespread they are no longer fitness-enhancing, but departing from them can have prohibitive fitness costs, effectively locking the population into a biologically and morally sub-optimal situation.

Second, even assuming that there is a positive correlation between the possession of attractive traits and the genetic fitness of their bearers (see Zahavi’s handicap principle; but see Fisherian runaway selection theory), humans would have evolved preferences for traits that correlated with fitness in the early ancestral environment, under selection pressures that have quite likely become obsolete in the modern developed world. To say that a trait or disposition is an adaptation is only to say that it is the product of a historical, cumulative selective regime—it makes no claim about the trait’s current utility or present contributions to fitness, let alone its implications for the human good.

Finally, because of the great plasticity of human behavior and social learning, it is likely that many or perhaps even most of the traits that we find attractive in mates today have little or no correlation with their fitness in the ancestral or contemporary selective environments. The modern sexual appeal of unhealthily apportioned women seems like an obvious example. Rather than spin-off just so stories to accommodate every sexual preference within an adaptationist framework, we would do better to recognize the importance of social learning and cultural transmission in shaping human preferences, including the vast array of sexual ones.

In sum, I am afraid that Scott’s argument, though provocative, founders in that it is committed to an unrealistic cognitive-ecology of procreative decisions, a fallacious Panglossian view of traits that are under sexual selection, and a conflation of biological fitness with the human good. The upshot: biological harms and moral harms often fail to coincide.