RESULTS
Experimentation on bonnet macaques with peanuts and examination of naturalistic foraging/feeding behavior in bonnet macaques, Japanese macaques and vervet monkeys revealed a high expression of hand use among urban groups (i.e., synanthropic groups) to acquire food which inevitably, also have a high encounter rate of packaged artificial food. Conversely, mouth use is relatively more prevalent among groups that are hardly exposed to packaged food and subsist under natural conditions. Despite the predominant combinatorial use of hand-mouth during extractive foraging of non-hard food items by primates, relative prevalence of hand use is maintained while deskinning a peanut under experimental condition but only in the urban group. Similar to the trend of mouth use observed in FA, even during peanut processing the rural group used their mouth more frequently relative to other groups.