This report presents the study results of the preliminary analysis of human remains, the mortuary practices and the social organization based on the human remains and the other archaeological evidence that discovered at Pra Thu Pha rockshelter site, Mae Mo District, Lampang Province on 1998 excavation season, approximately dates to 2,500-3,500 BP. As a total sample of 3,780 pieces of human bone including the uncovered six individuals can divide into at least 36 individuals consisted of 23 individuals from the first cultural layer and 15 individuals from the second cultural layer.
According to their sex and age at death estimation, there are ten infants or children (0-5 years), ten children or adolescents (5-15 years), and nineteen adults comprised of ten females, three males and six individuals who their sex was undetermined. Unfortunately, the male individuals had not completely long bones to estimate stature while the average stature of the female is 142.5 centimeters.
There are two distinct types of mortuary practices: 1) primary burial consisted of firstly practices, an extended burial with associated finds, and secondly, wrapped the remains with the bark woven or basketry with their associated finds and smoked before buried. 2) Secondary burial practices that composed of pieces of human bones placing on pieces of wood and covering with clothes, and then burnt or smoked before buried. Finally, this prehistoric population was a tribal organization that tended to bury their family or kinship together at the same place.