A South American anthropoid

Although there are many primate lineages in the Old World, it is thought that the New World is home to just one group, the platyrrhine monkeys, which appear to have colonized the region during the Eocene. Seiffert et al. describe a new primate species on the basis of fossil molars found in the Peruvian Amazon that appears to belong to the Parapithecidae, a group of stem anthropoid primates best known from northern Africa (see the Perspective by Godinot). The fossils appear to be from a well-differentiated lineage, suggesting that this species had been evolving within South America for some time. It is likely that the ancestors of this new species arrived via a transatlantic rafting event when sea levels dropped at the Eocene–Oligocene transition ∼32 to 35 million years ago.

Science, this issue p. 194; see also p. 136