Adaptability in stone tool use by wild capuchin monkeys (Sapajus libidinosus)

Area of Science:

• Primate behavior
• Archaeology
• Ecology

Background:

• Capuchin monkeys exhibit significant variation in stone tool use and diet across populations.
• Understanding adaptability in tool use is crucial for primate behavioral studies.

Purpose of the Study:

• To investigate stone tool use adaptability in a previously unstudied wild capuchin monkey (Sapajus libidinosus) population in a Caatinga environment.
• To identify food items processed using stone tools and the factors influencing tool selection.

Main Methods:

• Field study over 15 months in Serra Talhada, Pernambuco, Brazil.
• Identification and monitoring of 257 anvils and 395 hammers.
• Direct observation via trap cameras, recording 503 video clips, with 43 involving tool use.

Main Results:

• Five food types were identified: catolé palm, manioc, facheiro cactus, quípa cactus, and imburana de cambão.
• Food item characteristics (rigidity, size, spines) influenced stone tool choice.
• Cacti processing notably involved stone tools, likely due to spines.
• Anvil and hammer characteristics varied significantly based on the food item processed.

Conclusions:

• The capuchin monkey population in Serra Talhada demonstrates adaptability in stone tool use for food processing.
• Tool use provides access to otherwise difficult-to-acquire food resources in the Caatinga habitat.
• This adaptability highlights the complexity of foraging strategies in primates.