In partial response to Gill's statement, Professor of Biological Anthropology C. Loring Brace argues that the reason laymen and biological anthropologists can determine the geographic ancestry of an individual can be explained by the fact that biological characteristics are clinally distributed across the planet, and that does not translate into the concept of race. He states: The concept of "race" is still sometimes used within forensic anthropology (when analyzing skeletal remains), biomedical research, and race-based medicine. Brace has criticized forensic anthropologists for this, arguing that they in fact should be talking about regional ancestry. He argues that while forensic anthropologists can determine that a skeletal remain comes from a person with ancestors in a specific region of Africa, categorizing that skeletal as being "black" is a socially constructed category that is only meaningful in the particular social context of the United States, and which is not itself scientifically valid.