(PhysOrg.com) -- In a recent paper published in Behavioural Processes, scientists reveal a film of a mandrill monkey creating a tool from a stick in order to remove dirt from underneath its toenails. This new finding shows that monkeys may be more intelligent than scientists have previously believed.
While Great Apes like the chimpanzee and orangutan have been observed making tools to aid in the extraction of termites from mounds, this is the first time a smaller species of monkey has been observed making tools.
The discovery happened when lead researchers Dr. Riccardo Pansini was filming the mandrill as part of a stress-related behavior study being conducted at Chester Zoo. In the video, a large male mandrill works to pull apart bark on a twig to make the tool as narrow as he can. Once completed, he then uses the newly fashioned tool to clean and remove the dirt out from underneath his toenails.
Mandrills have also been seen modifying twigs to clean out their ears and researchers believe they do this in order to prevent ear infections. Pansini believes this new behavior of creating tools for pedicures may be due to the fact the mandrill is in captivity.
Because the mandrill is not focused on mating or finding food, he has the extra time on his hands to perform what could be considered as a trivial task. Yet, he has modified a tool that would normally be used for the hygienic purposes of cleaning out his ears and used it on his toenails.
However, other researchers are not as quick to call this tool usage. Dr. Amanda Seed from the University of St Andrews argues that the use of this twig for self-cleaning is not something new and is not sure that it really ranks up there with tool usage. The use of objects to help with self-care is just not the same as creating a tool to help find food like the chimpanzees do when collecting termites.
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More information: Observation of tool use and modification for apparent hygiene purposes in a mandrill, Behavioural Processes, doi:10.1016/j.beproc.2011.06.003
Tool making or modification to produce a tool of apparent improved functionality has rarely been reported in monkeys, especially when tools are used outside the context of food acquisition. We report on an observation of selection, modification and use of splinters for hygiene purposes in a male mandrill. The zoo-housed animal was video-recorded breaking splinters in sequence to use them underneath his toenails. This record brings forward new evidence that the ability to use and modify tools is not limited to apes and some New World monkeys but is also apparent in Old Word monkeys.