Plucked. Rebecca M. Herzig
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(Twenty-first-century evolutionary biologists analyze all these features and more.) Hairiness, however, forced particularly challenging questions about man’s relations to his primate fore-bears, as Darwin, like earlier naturalists, well realized. On the one hand, the very presence of hair would seem to fortify the claim that man is “descended from some ape-like creature.”6 As Darwin reasoned, “From the presence of the woolly hair . . . we may infer that man is descended from some animal which was born hairy and remained so during life.”7 And yet, that same thin scattering of hairs posed a rather inconvenient truth for the theory of natural selection, since the detriments of man’s relative hairlessness was readily apparent to anyone who had suffered through a clammy English winter. As Darwin explained, “The loss of hair is an inconvenience and probably an injury to man even under a hot climate, for he is thus exposed to sudden chills, especially during wet weather.”8 Darwin concluded that man’s “more or less complete absence of hair” reveals the limits of the arguments he laid out in the Origin of Species.9 “No one supposes that the nakedness of the skin is any direct advantage to man, so that his body cannot have been divested of hair through natural selection.”10
The problem Darwin faced in the Descent, then, was to make sense of characteristics that were useless at best and injurious or downright lethal at worst, given natural selection’s overarching insistence that advantageous variations persist over others. This dilemma was embodied most fully in what Darwin called the great “denudation of mankind”—man’s loss of hairy covering.11 Resolving this dilemma compelled Darwin to unfurl his controversial companion to the theory of natural selection: sexual selection. Thus the explicit goal of the latter sections of Descent, the chapters that discuss the inheritance of disadvantageous characteristics, is to show that such selection, “continued through many generations,” can produce effects on bodily form and appearance.12 Ultimately, Darwin attributed most of the differences of concern to his nineteenth-century readers—why some creatures were stronger or larger or more colorful than others—to the action of sexual selection. As he concluded in the Descent, “of all the causes which have led to the differences in external appearance between the races of man, and to a certain extent between man and the lower animals, sexual selection has been by far the most efficient.”13
DARWIN’S ADVOCACY OF sexual selection—and specifically its role in explaining man’s relative hairlessness—drove a wedge between Darwin and his longtime collaborator, Alfred Russel Wallace.14 Like Darwin’s Descent of Man, Wallace’s major book on human evolution, his 1870 Contributions to the Theory of Natural Selection, wrestled with how to accommodate seemingly useless or disadvantageous characteristics within the confines of the theory of natural selection. Chief among these troublesome characteristics was what Wallace called the absence of “hairy covering” in man. Other characteristics were similarly inexplicable, Wallace proposed, but perhaps not to “an equal degree.”15 Considering man’s hairless condition against the backdrop of other similarly perplexing phenomena led Wallace to conclude that man’s nakedness demonstrated “the agency of some other power than the law of the survival of the fittest.” In his view, hairlessness could be explained in no other way. As Wallace put it, a “superior intelligence has guided the development of man in a definite direction, and for a special purpose,” by means of “more subtle agencies than we are acquainted with.”16
More steadfast evolutionists quickly jumped on this point. In one 1870 lecture, the Devonshire naturalist and theologian T. R. R. Stebbing lambasted Wallace for failing to recognize the capacious meanings of “utility” in the struggle for existence. “[W]hat is selected through being useful in one direction may incidentally become useful in another,” Stebbing argued. “Had [Wallace] employed his usual ingenuity on the question of man’s hairless skin, he might have seen the possibility of its ‘selection’ through its superior beauty or the health attached to superior cleanliness.”17 Stebbing further mocked Wallace’s claims by ridiculing the idea of God as some sort of primordial cosmetologist:
[I]t is surprising that he should picture to himself a superior intelligence plucking the hair from the backs of savage men . . . in order that the descendents of the poor shorn wretches might, after many deaths from cold and damp, in the course of many generations take to tailoring and to dabbling in bricks and mortar.18
Such trappings of civility, Stebbing insisted, are “nothing more nor less than part and parcel of natural selection.”19
Recognizing body hair as the key point of contention, Darwin zeroed in on both Wallace’s statements and Stebbing’s critique. In Descent, Darwin echoed Stebbing’s dismissal of Wallace, and reasserted the absurdity of thinking that hairlessness was God’s way to force early men “to raise themselves in the scale of civilization through the practice of various arts.”20 Hairlessness had an explanation, to be sure—but its explanation was earthly rather than divine: men’s election of “superior beauty and cleanliness.” In the midst of his most important statement on human evolution, Darwin narrated his break with Wallace as a disagreement over the origins and purposes of body hair: where Wallace saw divine determination, Darwin saw individual choice.
“CHOICE” FOR DARWIN did not necessarily involve anything one might now consider deliberation or calculation on the part of the chooser. “As far as sexual selection is concerned,” Darwin wrote, “all that is required is that choice should be exerted.”21 Even if the individual member of a species does not intend to produce consequences on the bodies of his remote descendants, consequences there will be. As Darwin put it, “[A]n effect would be produced, independently of any wish or expectation on the part of the men who preferred certain women to others.”22 He repeated this point for emphasis: “[U]nconscious selection would come into action.”23 The potential for unconscious selection is key, since, again, the theory was developed to account for those features, such as hairlessness, which were, in Darwin’s words, “of no service” to animals “in their ordinary habits of life.”24 Man’s “partial loss of hair,” Darwin argued, is thus one of those “innumerable strange characters . . . modified through sexual selection.” It is not hard to believe, he assured, that a characteristic as injurious as hairlessness had been acquired in this way; for “we know that this is the case with the plumes of some birds, and with the horns of some stags.” Although unwieldy horns and plumes might obstruct key activities such as eating or escaping predators, females might find them attractive enough that, over time, an aberrant trait might eventually become widespread.25
But herein lies the problem. Quite unlike the fancy horns of the Irish elk or the resplendent plumage of the Bower-bird, human hairlessness is, according to Darwin’s own examples, a cultivated characteristic, the product of meticulous care. “[M]en of the beardless races,” Darwin himself wrote, “take infinite pains in eradicating every hair from their faces, as something odious, whilst the men of the bearded races feel the greatest pride in their beards,” and care for them accordingly.26 While sexual selection might well explain characteristics that seem to confer no other evolutionary advantage, the question remains as to exactly how one confers the effects of ornamental grooming on one’s offspring.
So how did early humans lose their hairy covering, if not through the inheritance of acquired characteristics—the very principle, proposed by French naturalist Jean-Baptiste Lamarck, that Darwin is generally credited with refuting? At this key juncture of the Descent of Man, Darwin skirted the Lamarckian implications of his explanation by employing the passive voice:
As far as the extreme intricacy of the subject permits us to judge, it appears that our male ape-like progenitors acquired their beards as an ornament to charm or excite the opposite sex, and transmitted them to man as he now exists. The females apparently were first denuded of hair in like manner as a sexual ornament.27
How that “first denudation” happened, occurring as it did when denudation was of no particular service, remains murky.
THE MURKINESS OF this narrative did not elude critics. One particularly witty 1871 satire by Richard Grant White—Shakespeare scholar, journalist, and father