The role of sucrose and sensory systems in fruit selection and consumption ofAteles geoffroyiin Yucatan, Mexico

Abstract

Our aim was to evaluate the role of sucrose and the role of smell, taste and touch in the selection and consumption of fruit in wild spider monkeys. We recorded the feeding bouts of 14 adults for 9 mo in the Otoch Ma'ax Yetel Kooh Reserve, Punta Laguna, Yucatan, Mexico. For each of 2346 inspections on fruits of six species the consumption or rejection and the use of touch, smell and taste was recorded. Ten fruit samples (five ripe and five unripe) from each species were collected and the sucrose concentration was determined with a refractometer. As expected, sucrose concentrations were higher in ripe than unripe fruits. The difference in sucrose concentration between ripe and unripe fruits was positively associated with the proportion of attempts on ripe fruits and the proportion of consumed ripe fruits. Furthermore, the senses of touch and taste were used more often when fruits were ripe, whereas the sense of smell was used more often when fruits were unripe. The results suggest that sensory cues and sucrose concentration play important roles in fruit selection in spider monkeys.

Chemical recognition of fruit ripeness in spider monkeys (Ateles geoffroyi)

“…These olfactory capabilities have been shown to be particularly tuned to detection, discrimination and identification of compounds common in fruits 8 9 10 11 12 . Additionally, behavioral studies from captivity and the wild demonstrated that non-human primates can rely on olfactory cues in fruit selection tasks 13 14 .…”

Visual detection and fruit selection by the mantled howler monkey (Alouatta palliata)

“…We defined acceptance as an animal consuming at least 75% of a given fruit (Pablo‐Rodríguez et al, 2015). We categorized fruits as cryptic , those that showed no noticeable color changes during their maturation, and were chromatically similar to the leaves.…”

“…Sugar is an important nutrient for primates and thought to be a key reward from fruits (Felton, Felton, Raubenheimer, & Foley, 2009). For example, in fruits selected by the spider monkey ( Ateles geoffroyi ), there is an increase in sucrose in those plant species that have fruit with one or more color changes during the ripening process, so that the color may be a potential indicator of sugar content (Pablo‐Rodríguez, Hernández‐Salazar, Aureli, & Schaffner, 2015). However, for howler monkeys, less is known.…”

“…There is a shortage of information on howler monkey fruit selection and the role of sugars. It has been reported that fruits that change to conspicuous colors have higher sugar content compared to cryptic fruits (Pablo‐Rodríguez et al, 2015; Sourd & Gautier‐Hion, 1986), but data are very sparse.…”

Olfactory sensitivity for mold-associated odorants in CD-1 mice and spider monkeys

“…It was, therefore, the aim of the present study to determine olfactory detection thresholds in a granivorous rodent, the house mouse ( Mus musculus ), and in a frugivorous primate, the spider monkey ( Ateles geoffroyi ), for an array of mold-associated odorants. It is well established that both species strongly rely on their sense of smell in the context of food selection (Laska et al 2007 ; Morris et al 2012 ; Nevo et al 2015 ; Pablo-Rodriguez et al 2015 ) and that both grains and fruits are prime targets of mold infestation (Jelen and Wasowicz 1998 ; Barkai-Golan and Paster 2008 ). A between-species comparison of olfactory detection thresholds allowed us to evaluate whether neuroanatomical properties such as the size of olfactory brain structures or genetic properties such as the number of functional olfactory receptor genes correlate with olfactory sensitivity.…”