Which senses play a role in nonhuman primate food selection? A comparison between squirrel monkeys and spider monkeys

Abstract

In order to optimize foraging efficiency and avoid toxicosis, animals must be able to detect, discriminate, and learn about the predictive signals of potential food. Primates are typically regarded as animals that rely mainly on their highly developed visual systems, and little is known about the role that the other senses may play in food selection. It was therefore the aim of the present study to assess which senses are involved in the evaluation of food by two species of New World primates: the squirrel monkey and the spider monkey. To this end, six animals per species were repeatedly presented with both familiar and novel food items, and their behavior was videotaped and analyzed. To obtain a further indication of the relative importance of visual and chemosensory cues, the animals were also presented with familiar food items that were experimentally modified in color, odor, or both color and odor. The results demonstrate that squirrel monkeys and spider monkeys use olfactory, gustatory, and tactile cues in addition to visual information to evaluate novel food, whereas they mainly inspect familiar food items visually prior to consumption. Our findings also show that in both species the use of nonvisual cues decreased rapidly with repeated presentations of novel food, suggesting a fast multimodal learning process. Further, the two species clearly differ in their relative use of nonvisual cues when evaluating novel or modified food, with spider monkeys relying more on olfactory cues than squirrel monkeys, and squirrel monkeys relying more on tactile cues compared to spider monkeys.

Olfactory sensitivity for putrefaction-associated thiols and indols in three species of non-human primate

“…As thiols and indols, in turn, have been found to be major products of the microbial degradation of proteins (Barker, 1981;Kamiya and Ose, 1984) and thus of putrefaction processes, which are usually accompanied by the production of toxins (Janzen, 1977), it seems reasonable to assume that primates should be highly sensitive to such compounds in order to avoid intoxication. Indeed, the food selection behaviour of primates suggests that they use their sense of smell for the evaluation of potential food items (Laska et al, 2007;Visalberghi and Addessi, 2000) and thus supports this assumption.…”

Eating with our eyes: From visual hunger to digital satiation

“…In humans, this activity relies primarily on vision, especially when it comes to finding those foods that we are already familiar with (see also Laska, Freist, & Krause, 2007). In fact, it has been suggested that trichromatic colour vision may originally have developed in primates as an adaptation that facilitated the selection of more energy-rich (and likely red) fruits from in-amongst the dark green forest canopy (e.g., Bompas, Kendall, & Sumner, 2013;Regan et al, 2001;Sumner & Mollon, 2000).…”

The first taste is always with the eyes: A meta-analysis on the neural correlates of processing visual food cues

“…Like other primates, humans have a highly developed visual system. Food selection, like many other behaviors, is primarily guided by the visual system (Laska et al, 2007;Linne et al, 2002). Not without reason, an ancient quote attributed to Apicius (first century) states that "the first taste is always with the eyes.…”