Neandertal bones found in a cave in Spain are what's left of an ancient murder-mystery, writes Carl Zimmer in The New York Times. Researchers led by Pompeu Fabra University's Carles Lalueza-Fox determined that there were 12 individuals in the group and, from knife marks on the bones, that they were the victims of cannibals. In addition to examining the bones, Lalueza-Fox and his colleagues turned to DNA analysis to determine the relatedness of the group.