Sexual Selection and Trichromatic Color Vision in Primates: Statistical Support for the Preexisting‐Bias Hypothesis

ArticleinThe American Naturalist 170(1):10-20 · August 2007with59 Reads
DOI: 10.1086/518566 · Source: PubMed
The evolution of trichromatic color vision in primates may improve foraging performance as well as intraspecific communication; however, the context in which color vision initially evolved is unknown. We statistically examined the hypothesis that trichromatic color vision in primates represents a preexisting bias for the evolution of red coloration (pelage and/or skin) through sexual selection. Our analyses show that trichromatic color vision evolved before red pelage and red skin, as well as before gregarious mating systems that would promote sexual selection for visual traits and other forms of intraspecific communication via red traits. We also determined that both red pelage and red skin were more likely to evolve in the presence of color vision and mating systems that promote sexual selection. These results provide statistical support for the hypothesis that trichromatic color vision in primates evolved in a context other than intraspecific communication with red traits, most likely foraging performance, but, once evolved, represented a preexisting bias that promoted the evolution of red traits through sexual selection.
    • "Further clarification of the selective forces acting on uakari colour vision will require behavioural studies. It will be of great interest to elucidate these mechanisms further, since uakaris may be a model for the evolution of colour vision in catarrhines, in which ancestrally evolved trichromatic colour vision for foraging then became co-opted for use in sociosexual signalling [73] (but see [74]). "
    [Show abstract] [Hide abstract] ABSTRACT: Colour vision is highly variable in New World monkeys (NWMs). 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. 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. Here, we investigate colour vision in a wild population of the bald uakari, C. calvus, by genotyping the X-linked opsin 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. This supports the presence of strong balancing selection on different alleles at this locus. We consider different hypotheses to explain this selection. One possibility is that trichromacy functions in sexual selection, enabling females to choose high-quality males on the basis of red facial 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. 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. 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.
    Full-text · Article · Apr 2016
    • "There are, however, other explanations for the evolution of preferences for particular color signals that are less adaptive. Species may develop sensory biases in one context, such as preference for ripe, red fruit (Fernandez and Morris, 2007). A preference for red evolved in a feeding context may lead to a general preference for red coloration, which can manifest itself in greater attraction to red individuals. "
    Full-text · Chapter · Mar 2016 · Proceedings of the Royal Society B: Biological Sciences
    • "At the same time, particular effects for red have also been shown for colour preferences (Bornstein et al 1976; Franklin et al 2009; Maier et al 2009) and for human behaviour in general (Elliot and Niesta 2008; Elliot et al 2007; 2009; Hagemann et al 2008; Hill and Barton 2005). Therefore, we wonder whether our results are linked to the fact that saturated red colours have special communicative functions in the natural environment, such as indicating alert, nutritious fruits, and sexual dispositions (for a discussion see, eg, Fernandez and Morris 2007, page 10). Thirdly, we could observe that the memory colour effect for our stimuli appeared independently of their perceptual complexity and of the abstractness of their colour diagnostic characteristics. "
    Dataset · Sep 2015 · Proceedings of the Royal Society B: Biological Sciences
Show more