From Matthew Cobb via Ed Yong, we have two orangs ripping apart and eating a slow loris. Slow lorises comprise a group of strepsirrhine primates (the group that includes lemurs and lorises, as distinct from the haplorhine primates, comprising tarsiers, monkeys, and apes). Orangs are, of course, supposed to be peaceful herbivores, subsisting mostly on fruits and leaves.
But as New Scientist reports (with this video), when plant food is scarce, Sumatran orangs (Pongo abelii; there are two species of orang, the other is the Bornean orang Pongo pygmaeus) hunt down one of the world’s cutest animals (made virally famous by the “tickled loris” YouTube vide0). Sporadic predation by orangs has been reported before, but the cases are accumulating, and actual hunting of other primates may be a culturally inherited behavior:
Madeleine Hardus of the University of Amsterdam in the Netherlands and colleagues have now observed three more cases, bringing the total to nine.
In 2007 Hardus was tracking two orangs in the canopy above her – a female called Yet and her infant Yeni – when Yet abruptly changed direction and approached a slow loris (Nycticebus coucang). She knocked it out of the tree, crashed down to the ground, bit the stunned loris’s head, then carried the body back into the tree to eat it. When Yeni begged, she was allowed to share the meat. The great apes each chomped on opposite ends of the dead primate, sharing it between them like lovers might a strand of spaghetti.
Searching through the scientific literature, Hardus found detailed studies of six orang-utan hunts. All stunned their prey before eating it, which Hardus thinks may be to avoid being bitten. Slow lorises are unique among primates in that their saliva is toxic.