tools to chop food. Chimps in the Nimba Mountains of Guinea, Africa, use both stone and wooden cleavers, as well as stone anvils, to process Treculia fruits.
The apes are not simply cracking into the Treculia to get to otherwise unobtainable food, say researchers.
Instead, they are actively chopping up the food into more manageable portions.
PhD student Kathelijne Koops and Professor William McGrew of the Leverhulme Centre for Human Evolutionary Studies, University of Cambridge, UK, studied a group of chimps living wild in the Nimba Mountains.
The apes' use of such tools can be surprisingly sophisticated. "For example, nut-cracking in the Bossou chimpanzee community in Guinea involves the use of a movable hammer and anvil, and sometimes the additional use of stabilising wedges to make the anvil more level and so more efficient," explains Ms Koops. "Termite fishing in some chimpanzee communities in the Republic of Congo involves the use of a tool set, i.e. different tool components used sequentially to achieve the same goal.
"These chimpanzees were found to deliberately modify termite fishing probes by creating a brush-end, before using them to fish for termites."
Floss after a meal. At least one does. A macaque in Japan flosses its teeth with its hair, demonstrating that humans aren't the only animals that clean their teeth and invent tools to help with the task.
The flosser, a free-ranging, middle-aged, female Japanese macaque named Chonpe, may have come up with the tool and the idea, according to a new study that will appear in the January issue of Primates.
Lead author Jean-Baptiste Leca told Discovery News that dental flossing could have been a fortuitous yet "accidental byproduct of grooming."
Leca, a post-doctoral fellow at Kyoto University's Primate Research Institute, explained that "Japanese macaques sometimes bite into hair or pull it through their mouths to remove external parasites."
The hair might have become stuck in Chonpe's teeth, and as she drew the hairs out, "she may have noticed the presence of food remains attached to them."
"The immediate reward of licking the food remains off the hair may have encouraged her to repeat the behavior for the same effect in the future," he added.