BURGOS, SPAIN—Live Science reports that the remains known as “The Boy of Gran Dolina” actually belonged to a young girl, based upon microscopic dental analysis which has been used to identify sex in other human species. The remains of 22 individuals, discovered in 1994 in Grand Dolina Cave, which is located in northern Spain’s Atapuerca Mountains, have been identified as Homo antecessor, a species that lived in Europe between 1.2 million and 800,000 years ago. But the remains are highly fragmented, perhaps because they had been cannibalized, and belonged to pre-adolescents, making it difficult to determine their sex. Older children, however, often have some adult teeth. Individual “H1” was thought to be a male who died at about 13 years of age, while individual “H3,” dubbed The Boy of Gran Dolina, was thought to be about 11 years old. Cecilia García-Campos of Spain’s National Center for Research on Human Evolution and her colleagues examined their upper canines and found that these two individuals were sexually dimorphic. When compared to the teeth of other hominins, H3 was determined to be likely a female. To read about nearly one-million-year-old footprints that may belong to Homo antecessor, go to "England's Oldest Footprints."