A Nonracial Craniofacial Perspective on Human Variation: A(Ustralia) to Z(Uni)
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AMERICAL JOURNAL OF PHYSICAL ANTHROPOLOGY 82:341-360 (1990) A Nonracial Craniofacial Perspective on Human Variation: A(ustralia) to Z(uni) C. LORING BRACE AND KEVIN D. HUNT Museum o Anthropology, University of Michi an, Ann Arbor, Michigan 48109 (C. .B.); Department of Anthropology, flarvard University, Cambridge,L Massachusetts, 02138 (K.D.H.) KEY WORDS Dental measurements, Race, C scores ABSTRACT Dental and craniofacial measurements were collected for 57 samples from Asia, the Pacific, the aboriginal western hemisphere, and Europe. The craniofacial dimensions include many that are not obviously under the control of specific selective forces. Similar configurations for these in different samples should yield indications of recency of common ancestry according to the logic expressed by Darwin and evident in the relationships indicated by nuclear DNA comparisons. Dental dimensions, however, vary according to the length of time that different intensities in selective forces have been in operation. The craniofacial measurements were transformed into C scores and used to generate Euclidean distance dendrograms. When all the material was used to generate a single dendrogram, the European and Amerindian samples sorted into two regionally identifiable clusters, and the Asian and Pacific material sorted into the three clusters identified in separate previous studies: a Mainland Asian cluster, a Jomon-Pacific cluster and an Australo-Melanesian cluster. Since these clusters are based on variation in traits that are basically nonadaptive in nature, no hierarchical ranking is possible. The clusters simply reflect degree of relationship. This technique holds forth the promise of producing a nonracial assessment of the relation- ships of all the peoples of the world, past and present. There is a spectrum of variation in what is shared a common ancestor. There is almost confusingly labeled “anatomically modern” certainly some ethnocentrism inherent in Homo sapiens that is rarely taken into ac- viewing the s ectrum as running from Eu- count in ap raisals of human evolution in rope to Austrayia, but this quite literally does general an individual fossil specimens in extend from one geographical extreme of the articular. 8In tooth size alone, the difference earth to the other, and, dentally at least, the getween the average condition in Australia Australian aborigines can legitimately stand and that in Euro e (or China) would satisfy for a morphological extreme in contempo- the criterion usea to indicate specific differ- rary H. sapiens and Europeans come quite ence (Gingerich, 1974,1979,1980; Gingerich close to representing their antithesis (Brace, and Schoeninger, 19791, yet there is obvi- 1980; Brace et al., in press b). ously no reproductive barrier between Aus- The aboriginal inhabitants of Australia tralians and anybody else in the world. All have been a continuing source of fascina- living human beings are demonstrabl mem- tion for anthropologists and the general bers of the same species even thoug there public alike ever since they were first en- are average visible differences betweenE the countered by itinerant Europeans almost various geogra hically situated populations 400 years ago. With the addition of an evolu- of the world. #he spectrum of variation is tionary perspective developed by Charles there, however, and it should be possible to Darwin after his visit there a century and a deal with it in such a fashion that we can half ago, that fascination invested them with determine how much of it is due to differ- more than just the status of benighted sav- ences in the intensity of s ecific selective agery that had previously prevailed. To be forces and how much of it is Bue to the length of time since the groups being compared Received June 23,accepted July 3,1989. @ 1990 WILEY-LISS, INC. 342 C.L. BRACE AND K.D. HUNT sure, much of that judgment continued una- 1944; Lack, 1961; Gould and Lewontin, bated, but to it was added an implication of 1979). The rise of the synthetic theory of the ‘‘ rimitive” in an evolutionary sense. evolution redirected scholarly enthusiasm Whet R er overt or uns oken, there has been a towards the study of characteristics with general assumption tR at Australian Aborig- measurable adaptive value, and the matura- ines represent the survival of an earlier tion of the science of genetics focused atten- stage in human evolution. Whatever their tion on traits with simple and discoverable age or sex, they have been repeatedly desig- modes of inheritance, whatever their adap- nated by the collective term “primitive man,” tive si ificance. Partially as a result of a kind of Pleistocene vestige that has been these cr evelopments, the relevance of skele- re arded as a veritable livin fossil. tal studies in general came under an increas- Fhis sort of appraisal has ta e same kind of ingly vocal attack (Boyd, 1950) that has con- t pological essentialism to it that underlies tinued up until the resent (Renfrew, 1987). tE e urge to identify cladistic status or “race” Initially, however, tR is simply served to shift (Brace, 1988). But if cladistic assessment the basis on which classification was estab- and racial designation are equally subjective lished from the mor hological henotypic enterprises, what can we do to make sense in level to the serologicaP genotypic Pevel. our consideration of those aforementioned Classification involved the identification Australian Aborigines or any other human and naming of a presumably fixed number of group during the course of an investigation “races,”whose individual members each con- of the spectrum of variation in H. sapiens? tained traits considered to be uniquely char- There are in fact two general approaches acteristic of the “race” in question. Still ear- that can be productive in very different ways lier, during the nineteenth century, there to help us understand the nature and rela- was a general consensus in physical anthro- tionships of any given population. One such polop that the various “races” had been approach is to assess the adaptive state of fixe entities for an immeasurably long pe- separate traits one by one in the perspective riod of time, possibly reflecting original cre- of the intensit and temporal duration of the ations-separate and unequal (Brace, 1982). individual seIy ective force that a plies to With the superficial addition of an evolution- each. The other is to assess the simiP arities to ary dimension to the expectations of physical and differences from other populations, both anthro ologists as the twentieth century near and far, by using traits and configura- rocee ed, the idea grew that each “race” tions that have little adaptive si ificance in {ad a differentB evolutionary trajectory, and and of themselves. No one stur y of limited that each had evolved to a greater or lesser scope can hope to do complete justice to both extent in comparison to each other (Coon, ap roaches. At best, one can as ire to pro- 1962). The assumption of differences in tim- vi cre an illustration of how and wR y each one ing and degree of that evolution allowed the can work. We attempt to do this in the sec- preservation of an assumed hierarchy no tions that follow. different in effect from the idea that differ- ences in worth had existed ad initio, and it underlies the invidious comparisons that THEORETICAL BACKGROUND continue to be offered (Rushton, 1985,1987, The demise of racial classification 1988). A generation and more ago, physical an- Finally, the conce t of race itself was thropology considered racial classification to shown to be devoid of \ iological justification be one of its principal tasks, and the pre- (Livingstone, 1962; Brace, 1964a,b). Conse- ferred technique used in the pursuit of this uently the whole enterprise of racial classi- goal was the comparative use of nonadaptive Fication, once at the core of professional traits (Hooton, 1926, 1931). Subse uently physical anthropology, was de rived of its the enthusiasm for the use of nona?i aptive scientific credibility and basicaP ly ceased to dimensions of mor hology waned (Hooton, exist. The social scientist, cognizant of the 1946)) and, with tK e Fisherian insistence inequities and injustices perpetrated in the that selection was the sole mechanism con- name of “race,” could well cry “good rid- trollin evolution, it became the accepted dance.” view ta at all aspects of mor hology were But human beings are not identical clones, controlled by selection and notK ing could be and their differences have re ‘onal and tem- regarded as non-adaptive (Dobzhansky, poral aspects to them that sfl ould certainly CRANIOFACIAL PERSPECTIVE ON HUMAN VARIATION 343 be the legitimate concern for biological an- Smouse and Li, 1987; Cann, 1988; Excoffier thropologists. Some investigators have actu- and Langaney, 19891, but there are some ally chosen to deal with one or another trait stochastic problems and other pitfalls that whose manifestation can be associated with keep it from bein our best general model differences in the intensity or duration of (Weiss, 1987; Spuf ler, 1988, 1989). The ap- specific selective forces (Livingstone, 1958, praisal of nuclear DNA on the other hand, in press; Brace, 1967, 1977, 1979, 1980; and despite some of its own attendant prob- Brace et al., 1987, in press c). Others have lems, can function as our basic example. concentrated on particular single gene phe- Ideally this would be best a proached by nomena and investigated the evidence for codon sequencing. In practice,K owever, this genetic drift and the founder effect in island is a tedious and nearly interminable process. PO ulations or other remote genetic isolates Doubts have also been expressed by some (GPass et al., 1952; Friedlaender and Stein- concerning the effectiveness of what has berg, 1970; Neel, 1970; Morton and Lalouel, been demonstrated by crude “brute force” 1973).