We have uncovered unexpected diversity in the last major lineage of NWMs to be assayed for colour vision, which will provide an interesting system to dissect adaptation of polymorphic trichromacy.Ĭolour vision is a key trait that has been fertile ground for demonstrating adaptations in animal sensory systems. Alternatively, the low proportion of heterozygous female trichromats in the population may indicate selection on different dichromatic phenotypes, which might be related to cryptic food coloration. In support of this, there is some evidence that health affects facial coloration in uakaris, as well as a high prevalence of blood-borne parasitism in wild uakari populations. One possibility is that trichromacy functions in sexual selection, enabling females to choose high-quality males on the basis of red facial coloration. We consider different hypotheses to explain this selection. This supports the presence of strong balancing selection on different alleles at this locus. We document the presence of a polymorphic colour vision system with an unprecedented number of functional alleles (six), including a novel allele with a predicted maximum spectral sensitivity of 555 nm. calvus, by genotyping the X-linked opsin locus.
Here, we investigate colour vision in a wild population of the bald uakari, C.
#Bald chimpanzee skin#
The colour vision of uakaris ( Cacajao) is of particular interest because these monkeys have the most dramatic red facial skin of any primate, as well as a unique fission/fusion social system and a specialist diet of seeds. Evidence for the adaptive basis of colour vision in this group has largely centred on environmental features such as foraging benefits for differently coloured foods or predator detection, whereas selection on colour vision for sociosexual communication is an alternative hypothesis that has received little attention. Colour vision is highly variable in New World monkeys (NWMs).