This fossil cranium of a new stem catarrhine from western Saudi Arabia allows palaeontologists to place a more accurate date than previously possible on the divergence of cercopithecoids (Old World monkeys) and hominoids (apes and humans) within Old World higher primates (Catarrhini). The new specimen dates to the mid-Oligocene, around 29 million to 28 million years ago, and has no crown catarrhine specializations other than the presence of a tubular ectotympanic, suggesting that the divergence of Old World monkeys and hominoids happened after that date. The cover shows the anterior view of the cranium, which has its lateral incisors, canines and broad molars in situ. The size of the cranium indicates a medium-sized primate, between 15 and 20 kilograms in body mass. Photo credit: Daniel Erickson/Bonnie Miljour, University of Michigan.