Washington [US], November 18 (ANI): Capuchin monkeys (Sapajus spp.) are among only a few primates that use tools in day-to-day activities.
In the Cerrado and Caatinga, they use stones as hammers and anvils to crack open cashew nuts, seed pods of Hymenaea courbaril (West Indian locust; jatoba in Brazil) and other hard foods.
In their study, the researchers observed three populations of bearded capuchin monkeys (Sapajus libidinosus), measuring food hardness, tool size and weight, and local availability of stones. They concluded that culture, defined as information passed on from one generation to the next by social learning, can also influence behavior in this regard.
The population to which he referred lives in Chapada dos Veadeiros National Park in Goias, a state in Brazil's Center-West region. In the study, this population was compared with capuchins living in Serra das Confusoes National Park, in Piaui, a state in the Northeast region, and another population that lives in Serra da Capivara National Park, about 100 km away in the same state.
"In Serra das Confusoes, they use smaller tools to open smaller and softer fruit but use large, heavy hammers to crack coconut shells, which are very hard. In Chapada dos Veadeiros, where there are stones of varying sizes to choose from, they use the heaviest ones even for fragile foods," Falotico said.
Measurements
"We expected to find a very close correlation between the type of food and the size and weight of the tool, but the population in Chapada dos Veadeiros mainly used the larger ones even though stones of all sizes are plentiful and they can choose a smaller size. They probably inherited this habit from their ancestors. It's a cultural difference compared with the other populations," Falotico said.
"Their behavior isn't due to the availability of resources but to cultural heritage," Falotico said.
The study was also supported by FAPESP via a scholarship awarded to Tatiane Valenca, a PhD candidate at EACH-USP.
A paper by Falotico and a team of archeologists from Germany, Spain and the United Kingdom, published in the Journal of Human Evolution, reports the results of field experiments conducted to test the potential for accidental flake production during nut cracking by capuchins using various types of rock as anvils.
The monkeys did not use the flakes, which closely resembled the lithic tools found by archeologists at digs around the world. The researchers believe the earliest hominins obtained flakes accidentally before their deliberate production for use as tools.
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