Because tools play a central role in human culture and evolution, their manufacture and use by non-human animals are a fascinating subject of investigation [1
]. While it is known that wild animals of different taxonomic groups are capable of using tools [2
], a flexible tool repertoire has been commonly ascribed only to chimpanzees and orang-utans (e.g. [3
]). However, growing evidence, obtained in dry regions of Brazil (savannah-like vegetation), suggests that capuchins are also versatile users of tools (see Ottoni & Izar [5
] for a review).
The arid environment where tool use has been observed in capuchins has influenced current explanations for the disjunct distribution of tool use across dry and humid habitats. Moura & Lee [6
], for example, suggested that food scarcity (motivational factor) and terrestrial habits (through which monkeys had access to tubers, roots and some insects by digging with stones) were the main factors for the occurrence of tool use in those primates. More recently, Ottoni & Izar [5
] concluded that food scarcity is of peripheral importance, after noting that tool use can occur in groups of capuchins with provisioning and is absent in others during periods of food scarcity. The latter proposed that terrestrial habits, which free the monkey's hands to transport tools as they travel bipedally and also provide stable and relatively flat surfaces to practise tool-using behaviour, are the most important behavioural factors promoting tool use in wild capuchins [4
]. Given the limited data on tool use in wild capuchins, the propositions supporting the appearance of tool use remain unclear.
Termites are abundant in all tropical biomes, and are a nutritious food source for many animals, including humans [7
]. The use of sticks to extract termites by wild chimpanzees was originally observed in the forests of Gombe [8
], and this phenomenon rapidly became one of the best known and most influential discoveries involving animal tool use.
We report here the spontaneous modification and use of sticks to fish for termites observed in one group of wild blonde capuchins (Cebus flavius
) living in a fragment of Atlantic Forest (a
). This species was recently rediscovered, after presumed extinction [9
]. We also report the use of two techniques employed sequentially by the capuchins during termite fishing that have never been described in other non-human primates, including chimpanzees. Experiments with humans playing the role of termite fishers in the monkeys' habitat were also conducted to test the effectiveness of the fishing techniques employed by the animals.
Figure 1. (a) A blonde capuchin (Cebus flavius) in the study site. (b) Distribution of termite fishing activity across the observational period (days and months are in italic; AM refers to ‘adult male’ and the number to its identity). Background (more ...)