Craniofacial anthropometry
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- This article deals with races defined craniofacially (based on skull measurements) and not by typology (physical type) or genetic distance. Races categorized using alternative methods yield different groups, making them non-concordant.[1]
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Craniofacial anthropometry is a technique used in physical anthropology comprising precise and systematic measurement of the bones of the human skull. Among its more important applications are: forensics, facial reconstruction, and paleoanthropology. The field of phylogeography, on the other hand, once relied heavily on this technique but no longer does so.[2] Craniofacial anthropometry is a sub-field of Craniometry, which see for more detail and history.
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[edit] History
The historical development of craniofacial anthrometry started when anthropologists first measured human skulls as a way to categorize race. The beginning physical anthropologists used a holistic method where they examined multiple observable physical characteristics to determine race. This holistic approach was not "craniofacial anthrometry" but a typological method. As anthropologists gained access to methods of skull measure, they developed racial classification based off skull shape. The observable craniofacial skeletal differences ranged from breadth of nasal aperature, nasal root height, head shape e.g. mesocephalic, brahchycephalic and doliocephalic, sagittal crest appearance, jaw thickness, browridge size, forehead slope, etc., but did not involve soft tissue differences such as nasal shape, eye color, skin color, lip shape, and hair type. Using a strictly skull based categorization method, these anthropologists organized three to four racial groups. Caucasoids were characterized by a doliocephalic shape, with receded zygomas, large browridge and a narrow nasal aperature. Secondly, Negroids were characterized by a mesocephalic head shape, with receded zygomas and wide nasal aperature. Third, Mongoloids were characterized as a brachycephalic head shape, absent browridges, small nasal aperature, and projecting zygomas. Additionally, Australoids whose craniofacial type fell between Negroids and Caucasoids was added. With the addition this category, Thomas Huxley considered India to fall in this groups craniofacial measurements[3] while Cavalli-Sforza claimed India would best fit craniofacially as Caucasoid.
Carleton S. Coon, author of the controversed Races in Europe, used the technique for his The Origin of Races (New York: Knopf, 1962). Because of the inconsistencies in the old three-part system (Caucasoid, Mongoloid, Negroid), Coon adopted a five-part scheme. He discarded the term "Negroid" as useless or misleading since it implied a dark skin-tone, which is found low lattitudes around the globe. As shown in the map, he defined "Caucasoid" as a pattern of skull measurements typical of humans indigenous to an area including Europe, South Asia, West Asia, of North Africa, Central Asia, and parts of sub-Saharan Africa (Senegal, Gambia, Chad, Burkina Faso, Ethiopia, and Somalia). He defined skulls typic of equatorial Africa as "Congoid" and those of southern Africa as "Capoid." Finally, he split "Australoid" from "Mongoloid" along a line roughly similar to the modern distinction between sinodonts in the north and sundadonts in the south based on teeth shape.
In another work, The Races of Europe, Coon classified Caucasoids into "races" named after regions or archeological sites such as Brünn, Borreby, Alpine, Ladogan, East Baltic, Neo-Danubian, Lappish, Mediterranean, Atlanto-Mediterranean, East African, Irano-Afghan, Nordic, Hallstatt, Keltic, Tronder, Dinaric, Noric and Armenoid. These subraces were typologically-defined by other factors than skull shape, including nasal shape and skin color. This extremely typological view of "race" was, even at the time of publication in 1939, becoming seen as very much out of date among many anthropologists.
[edit] In forensic anthropology
See main article: Forensic anthropology.
Forensic anthropologists study the human skeleton in a legal setting, most often in criminal cases where the victim's remains are more or less skeletonized. A forensic anthropologist can also assist in the identification of deceased individuals whose remains are decomposed or otherwise unrecognizable. The adjective "forensic" refers to the application of this subfield of science to a court of law. Craniofacial anthropometry of a person's remains can help determine what the person looked like when alive. Also, due to the requirements of the U.S. judicial system[citation needed], U.S. forensic practitioners are sometimes asked to classify remains into one of the U.S. socially-enforced endogamous groups: Black, White, or East Asian. In legal practice, these are sometimes termed, respectively, "Negroid," "Caucasoid," and "Mongoloid," or even the older "Caucasian," "Negro," and "Oriental." Nowadays, the terms "Black," "White," and "East Asian" are the more common usage.
"Caucasoids" are generalized to have the lowest degree of projection of the alveolar ridge bones which contain the teeth, a notable size prominence of the cranium and forehead region, and a projection of the midfacial region. "Negroid" traits are generalized to include more rounded eye sockets; broader, more rounded nasal cavity; a forward-slanting facial profile (prognathism); and a dolichocephalic skull (proportionally longer from front to back).
[edit] In medicine
Surgeons employ the methods of craniofacial anthropometry in order to reconstruct a patient's face, when necessary, to fit within the limits of what society expects.
[edit] In paleoanthropology
Paleoanthropologists employ craniofacial anthropometry in the study of fossilized hominid bones in order to identify the species. Specimens of Homo erectus and athletic specimens of Homo sapiens, for example, are virtually identical from the neck down but their skulls can easily be told apart.
[edit] In phylogeography
Phylogeography (see main article) is the science of identifying and tracking major long-distance migrations that bands of humans undertook, especially in prehistoric times. For a detailed account of Human migrations see that article. Linguistics can follow the movement of languages and archaeology can follow the movement of artifact styles, but neither can tell whether a culture's spread was due to a source population's physically migrating or to a destination population's simply copying the technology and learning the language. Craniofacial anthropometry helped resolve this because a people's physiognomy does not change rapidly due to mere migration.
[edit] Racial determination example
That craniofacial anthropometry is not as replicable as other ways of tracking human variation makes its findings difficult to explain.[citation needed] Here is a trivial example: imagine that you are handed a U.S. skull and asked to determine whether the person was White, Black, or Asian (that is, Euro-American, African American, or Asian American). Place the skull face down on a tabletop. Now try to rock it from side to side. If it fails to rock, but instead sits high on its cheekbones, with a face too flat to let the nose portion touch the table, then the chances are that it is of east Asian ancestry. If it rocks from side to side because the midline of the face protrudes past the cheekbones like the bow of a boat, then it is probably of either African or European ancestry. Now stand the skull upright so that it rests on the neck opening. If the face slopes down and forwards because the mouth protrudes farther forward than the forehead, then it is likely of west African ancestry. If the face is vertical, it is probably of European ancestry. In practice, many other tests are necessary in order to hazard a determination but, in the end, it works because there are consistent differences among U.S. endogamous groups. A skull that matches the group of features associated with African-American ancestry is called "Negroid." Skulls with traits suggesting European and Asian ancestry are called, respectively "Caucasoid" and "Mongoloid."
[edit] Challenges
- See also: Race
Although it is categorization of a skull is clear given arbitrary parameters, it will not locate the owners geographic ancestry concretely all the time. While one's perception of an individual's race can be affected by cultural aspects, the "race" of his skull is less ambiguous. As Dr. Stan Rhine put it, "...it is clear that race does mean different things to different people. In the context of forensic anthropology, the term race is unambiguous."[4] Although their craniofacial race based on skull indeces is unambiguous, it will not pin point their geographic origins accurately all the time due to variation in skulls within a geographic region. For example, racial categorization by craniofacial type will categorize some East and South Indians to have "Negroid" skulls and others to have "Caucasoid" skulls, for example, while Ethiopians, Somalis, and some Zulus have "Caucasoid" skulls, and the Khoisan of southwestern Africa have "Mongoloid" skulls[citation needed].
While this method produces useful results for the population of the United States, it is likely that it would not be reliable for populations from other countries.[5] This is due to the fact that the United States has traditionally had groups whose ancestry came from geographically distant locations, and which have generally remained endogamous in this country, for social reasons. The craniofacial difference between Northern Europeans, West Africans, East Asians/Native Americans is quite pronounced and fall easily within the indeces used to determine race from skull type.[citation needed] As more immigrants from in between regions and as Americans become more racially mixed, such craniofacial identification is problematic.
Classification by craniofacial anthropometry does not necessarily coincide with genetic ancestry or social self-identification. For example, about one-third of so-called "White" Americans have detectable African DNA markers.[6] And about five percent of so-called "Black" Americans have no detectable "Negroid" traits at all, neither craniofacial nor in their DNA.[7] In short, given three Americans, one who self-identifies and is socially accepted as U.S. White, another one who self-identifies and is socially accepted as U.S. Black, and one who self-identifies and is socially accepted as U.S. Hispanic, and given that they have precisely the same Afro-European mix of ancestries (one "mulatto" grandparent), there is quite literally no objective test that will identify their U.S. endogamous group membership without an interview.[8] In practice, the application of such forensic criteria ultimately comes down to whether the skull "looks Negroid," "Caucasoid," or "Mongoloid" in the eye of each U.S. forensic practitioner.
[edit] The debate over craniofacial and genetic concordance
One psychologist named Arthur Jensen believes geneticist Cavalli-Sforza's genetic maps made around the 1980s correspond exactly with craniofacial anthrometry groups, but newer genetic maps from Dr. Eduardas Valaitas made in 2007 do not correspond to craniofacial groups.
[edit] Footnotes
- ^ John Relethford, The Human Species: An introduction to Biological Anthropology, 5th ed. (New York: McGraw-Hill, 2003).
- ^ The current standard reference is John C. Kolar and Elizabeth M. Salter, Craniofacial Anthropometry: Practical Measurement of the Head and Face for Clinical, Surgical, and Research Use (Springfield IL: C.C. Thomas, 1997).
- ^ Huxley, Thomas. On the Geographical Distribution of the Chief Modifications of Mankind. 1870. August 14, 2006. <http://aleph0.clarku.edu/huxley/SM3/GeoDis.html>.
- ^ http://library.med.utah.edu/kw/osteo/forensics/race.html.
- ^ The Online Companion to California Newsreel's 3 part documentary about race and society, science and history, "Race — The Power of an Illusion", Ask the Experts section
- ^ Heather E. Collins-Schramm and others, "Markers that Discriminate Between European and African Ancestry Show Limited Variation Within Africa," Human Genetics 111 (2002): 566-9; Mark D. Shriver and others, "Skin Pigmentation, Biogeographical Ancestry, and Admixture Mapping," Human Genetics 112 (2003): 387-99.
- ^ E.J. Parra and others, "Ancestral Proportions and Admixture Dynamics in Geographically Defined African Americans Living in South Carolina," American Journal of Physical Anthropology 114 (2001): 18-29, Figure 1.
- ^ Carol Channing, Just Lucky I Guess: A Memoir of Sorts (New York: Simon & Schuster, 2002); Gregory Howard Williams, Life on the Color Line: The True Story of a White Boy who Discovered he was Black (New York: Dutton, 1995)
