Video analyses of naturalistic food acquisition and food extraction/processing of primate species
Hill (2018) compiled a list of 113 primate species that forage on cultivars and we have enlisted at least 16 primate species that are known to subsist around urban landscapes. We mined videos of 3 primate species from video databases/archives such that they spanned the urban-forest gradient alongside the possibility of acquiring packaged artificial food. Videos obtained covered foraging and feeding by primates in as many microhabitats of each species as possible and included their natural habitats (e.g., temperate evergreen forest, savanna), altered habitats (e.g., botanical garden, nature-park, linear structures through forests) and anthropogenic habitats (e.g., farmland, tourist spots, residential areas). Based on availability of videos and all relevant information, we included the following cercopithecid species in the analyses: bonnet macaque (Macaca radiata ), Japanese macaque (Macaca fuscata ) and vervet monkey (Chlorocebus pygerythrus ). Several widespread primate species (e.g., rhesus macaque, long-tailed macaque) could not be included in the analyses due to inadequate video records or habitat representation(s).
We identified the year of video recording/uploading and the geographical location of the primate group(s) based on the metadata of video. Among videos containing foraging and feeding incidences, we shortlisted instances in which food items met the conditions described in Table 1. The conditions for food inclusion were based on delimiting the overlap of mouth use and hand use for FA and the overlap of mouth use, hand use and hand-mouth use for FP. Most conditions elucidated in Table 1 were based on research literature on grasp, food acquisition, reach-for-food and reach-for-grasp in primates (e.g. Peckre et al., 2019; Pouydebat & Bardo, 2019; Sustaita et al., 2013). The remaining conditions were determined based on the logical evaluation of an equal likelihood of hand/mouth use in FA and FP with regard to species-food pairs. Several covariates including variables for habitat (urbanization, packaged food), individual characteristics (age), foraging style and characteristics of food (attachment, embeddedness) were considered. The description and inclusion/exclusion criteria of each covariate are provided in Table 2. The covariates and their scopes described in Table 2 were also drawn from published materials (e.g. foraging style: Le Gros Clark, 1959; Szalay et al., 1987; Van Horn, 1972; age: Colell et al., 1995; food size/shape: Peckre et al., 2019; Reghem et al., 2011; food consistency: Peckre et al., 2019; material texture: Yokoi et al., 2018; prey mobility: Peckre, Lowie, et al., 2019; Toussaint et al., 2013; foraging substrate: Fabre et al., 2017; Peckre, Lowie, et al., 2019; Toussaint et al., 2013). Two researchers (TD and SD) naïve of the habitat and ‘encounter with packaged food’ characterization of the groups in the videos coded a random set of videos to (1) standardize the coding framework mentioned in Table 2 and to (2) evaluate inter-coder consistency in identifying hand/mouth use for FA and FP, age, foraging style, food embeddedness and food attachment, i.e., attachment of the fruit to the plant. To characterize the degree of exposure to packaged anthropogenic food, we obtained information from either researchers familiar with the groups, videographers, published/unpublished research, residents of the region and/or from the narration in the videos.