Madeleine Hardus and colleagues [1] describe long-term observations of hunting by Sumatran orangutans.
The paper is straightforward in its description of the hunting observations: They hunt slow lorises, the practice is rare, it occurs at times when their other preferred foods are scarce, some individuals hunt but most don't, and food sharing among individuals other than mother-infant pairs wasn't observed. This isn't the first time hunting has been reported by wild orangutans, what it does is report a longer-term observation of one hunting female, tying this case to earlier observations.
I'm pointing to the paper because it includes some discussion about the requirements of meat eating for early hominins. These orangutans take a long time to chew up a slow lorus.
