Here are some quotes from Adams (2007) on ethnicity in anthropology.
Generally, forensic anthropologists tend to classify individuals into three main groups: Caucasoid, or white/European; Negroid, or black/African; and Mongoloid, or Native American/Asian. Clearly, these groups do not encompass the diversity of the modern world, and the skeletons of some people do not fit comfortably into these broad classifications………
The best area to estimate race/ancestry is from the skull, especially the bones of the face. While features of the postcranial skeleton may also be observed, most forensic anthropologists will first look to the skull and teeth for answers. Many of the differences are relative, meaning that they vary on a scale (e.g., narrow versus wide, or present versus absent) and a familiarity with the range of human variation is essential.
Adams goes on to identify physical attributes which are used to classify skulls which include:
- Nasal aperture;
- Nasal sill/guttering;
- Carabelli’s cusp;
- Alveolar prognathism;
- Shape of thigh bone; and
- Shovel-shaped maxillary incisors.
So does this mean that there are races? Not necessarily. Rather, it means that there are anthropological categories which have verifiable physical attributes.
Let’s assume that there is a population of 100 people (Group O) who exhibit normal physical variations. To keep it simple, let said variations only be skin tone which vary in a continuum. Let us further assume that there is some event which causes the formation of 4 groups which separate themselves from each other. However, all 4 groups have all the skin tone variations but in different amounts.
Let Group A have more pink skins, Group B, more dark brown skins, Group C, more brown skins and group D, more light brown skins. In time, we would expect that there would be a preponderance of skin tones according to the dominant gene in a group and the level of skin coding genetic mutations.
This is what we find today. Separated populations have predominant skin tones within a smaller range. Does that mean that there are four separate races? Recall, that all four groups had input from persons with a continuum of tones. The answer would be no even if there are legitimate present features which can be used to accurately identify all of the members of the four groups.
This may be where racists go wrong in that they think that because there are physical attributes which can identify an individual’s group accurately, that said features indicate strongly fixed original groups instead of genetic and anthropological similarity due to separateness (i.e. group O producing groups A, B, C and D). Sadly, we have to wait on genetics to provide more data; though, it doesn’t look promising for those who think they’re for the most part, racially “pure.”
Source: Adams, Bradley. 2007. Forensic Anthropology. New York, USA: Chelsea House: 43-44.