In “Vegetarian orang-utans eat world’s cutest animal” (New Scientist, 17 January 2012) Michael Marshall reports,
When fruit is scarce, try chomping on a slow loris. That seems to be the strategy adopted by the normally vegetarian orang-utans, which have been spotted knocking the small primates out of trees and killing them with a bite to the head.
Note the following:
All the documented hunts took place when there was little fruit available, which may push the apes to meat-eating, says Hardus.
By contrast, chimpanzees hunt more when fruit is abundant, perhaps because it doesn’t matter if they waste energy on a failed hunt.
Translation from the Darwinese: A number of great apes are carnivorous at times, and no simple rule seems to govern their preferences.
We didn’t realize that the slow loris was the world’s cutest animal: Here is a video argument for that view: