Evolutionary consequences of colour perception of Sapajus apella (Primates, Platyrrhini)

Abstract

This study aims to understand the evolutionary implications of the intraespecific diversity in color vision in plathyrrine primates, which is determined by the middle- and long-distance opsin encoding gene. The locus responsible for trichromatic vision is found on the X chromosome, thus only heterozygous female individuals show this trait. For the study, a sample of seven Sapajus apella was used. All the male individuals used for the study had dichromatic vision, while some females had dichromatic vision and some others trichromatic. Behavioural studies were carried out to understand the different behaviours between the dichromatic and trichromatic individuals. While trichromatic specimens spent more time in foraging (focusing in red and orange foods), dichromatic ones spent more time in social activities. These differences are proposed to be the result of the contrasting strategies taken by dichromatic and trichromatic individuals in order to increase their food resources and chances of survival.