Anthropology refers to the study of human origins.
Within the Stargate program, Daniel Jackson was the first to put it into use determining the background of the people of Abydos. After it was acknowledged that, if the human race mostly came from Earth, most human populations on alien planets could trace their histories to Earth history. Therefore, their customs, language, and even how they got to be placed to their respective alien planets could be deduced by their respective ancestors on Earth.
SG-3 included someone that probably had a background in Archaeology or/and anthropology and one could assume Stargate Command employed more to study races encountered that had ties to ancient earth. There are several reported cases where knowledge of a planet's people's ancestral origins lead to breakthroughs for SG teams; For example in identifying supposed gods, technologies or alien races such as the Goa'uld or the Asgard.