Complex sentence: Returning to Mexico as a permanent resident, he joined the staff of the Universidad Nacional Autonima de Mexico and subsequently became head of the department of Anthropology at Mmexico City College, which position he held at the time of his passing on January 2,1951.
Split into simpler sentences: Returning to Mexico as a permanent resident, he joined the staff of the Universidad Nacional Autonima de Mexico. He became head of the department of Anthropology at Mexico City College, which position he held at the time of his passing on January 2,1951.