Are badges of status adaptive in large complex primate groups?

Grueter, Cyril C.; Isler, Karin; Dixson, Barnaby J.

doi:10.1016/j.evolhumbehav.2015.03.003

Cited by 84 publications

(80 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although the mating system of uakaris is poorly understood, there is strong circumstantial evidence for a polygynous system related to male coloration. Uakaris have large group sizes and fission-fusion behaviour [30], which are associated with greater male ornamentation in primates [38]; sexual dimorphism in visual traits is stronger in polygynous primates [58], and there is some evidence that subgroups of uakaris are composed of affiliative male units that are outnumbered by females [59]. In addition, large group sizes in NWMs are associated with simple facial patterns, as found in uakaris [60].…”

Section: Discussionmentioning

confidence: 99%

“…In this species, the red coloration extends over the entire head, which is sparsely haired, unmelanized and an intense scarlet, due to the underlying blood supply [34,35]. The red coloration is subjectively more intense in adult males in comparison with females [36], and the enlarged temporal muscles of the adult males further exaggerate the trait in this sex [37,38]. In addition, the overall pelage colour is reddish orange or reddish golden [32].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Highly polymorphic colour vision in a New World monkey with red facial skin, the bald uakari (Cacajao calvus)

et al. 2016

View full text Add to dashboard Cite

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.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Highly polymorphic colour vision in a New World monkey with red facial skin, the bald uakari (Cacajao calvus)

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Of all the human secondary sexual traits, 98 amongst the most sexually dimorphic and visually conspicuous is beardedness 99 (Dixson et al, 2005;Grueter et al, 2015). Facial hair grows due to the combined 100 actions of the androgens dihydrotestosterone (DHT) and testosterone (Randall,Beards may enhance perceptions of men's dominance and masculinity 141 because they emphasise sexually dimorphic aspects of underlying craniofacial 142 shape (Goodhart, 1960;Guthrie, 1970 increasing jaw size and facial length, they may also decrease perceptions of 147 attractiveness owing to breaching a threshold of masculinity at which facial hair 148 enhances male attractiveness (Dixson & Brooks, 2013;Neave & Shields, 2008).…”

mentioning

confidence: 99%

Beneath the beard: do facial morphometrics influence the strength of judgments of men's beardedness?

Dixson

Lee

Sherlock

et al. 2017

Evolution and Human Behavior

View full text Add to dashboard Cite

50Converging evidence suggests men's beards, like many androgen-dependent 51 masculine secondary sexual traits, communicate masculinity and dominance 52 intra-sexually while effects of men's beardedness on attractiveness ratings are 53 more equivocal. Beards may enhance perceived masculinity and dominance via 54 amplifying aspects of underlying craniofacial masculinity, particularly the size of 55 the lower face and jaw. Here we tested these predictions across two studies. In 56 Study 1, we tested how three facial metrics -objectively measured craniofacial 57 masculinity, facial-width-to-height ratio (fWHR), and jaw size -calculated while 58clean-shaven impacted on ratings of attractiveness, masculinity and dominance 59 of 37 men photographed when clean-shaven and with full beards. Results 60showed that beards exerted significant and positive effects on masculinity, 61 dominance and to a lesser extent attractiveness. However, fWHR did not 62 significantly interact with beardedness to influence the directions of any of the 63 ratings, and while some linear and nonlinear interactions were significant 64 between objective craniofacial masculinity and beardedness as well as between 65 jaw size and beardedness, they tended to be subtle and dwarfed by the large 66 main effect of beardedness on perceptual ratings. In Study 2, we measured 67 ratings of attractiveness, masculinity and dominance for composite clean-shaven 68 and bearded stimuli experimentally manipulated in facial shape to represent 69 ±50% the shape of a beard, essentially manipulating the size of the lower face 70 and jaw of the stimuli. We found a strong main effect whereby bearded stimuli 71 enhanced dominance and masculinity ratings over clean-shaven stimuli. 72Increasing the size of the lower face and jaw augmented ratings of masculinity 73 and dominance in clean-shaven stimuli but did not exert strong effects within 74 bearded stimuli. Attractiveness ratings were highest for bearded faces with 75 smaller jaws followed by bearded and clean-shaven faces with larger jaws and 76 lowest for clean-shaven faces with small jaws. Taken together, our findings 77 suggest that beards exert main effects on masculinity and dominance possibly by 78 amplifying male typical facial shape. Attractiveness ratings of facial hair may 79 reflect a compromise between overly dominant looking faces with larger jaws 80 and the additive effects beardedness has on these ratings. 81 82

show abstract

“…In other cases, secondary sexual traits provide information regarding age, dominance and rank within social groups (A. F. Dixson et al, 2005;Grueter et al, 2015;Sheehan & Bergman, 2015). Converging evidence suggests men's secondary sexual traits also play a strong role in intra-sexual communication of age, masculinity and dominance (Puts, 2010(Puts, , 2016 and function during intra-sexual agonistic displays (Puts et al, 2015).…”

Section: Discussionmentioning

confidence: 99%

“…Among the anthropoid primates, visually conspicuous secondary sexual traits provide information used by males to assess the sexual maturity, dominance and rank of other males (A. F. Dixson, Dixson, & Anderson, 2005;Grueter, Isler, & Dixson, 2015).…”

Section: Introductionmentioning

confidence: 99%

Testing Evolutionary Hypotheses Regarding Individual Differences in Human Mating Strategies

Sherlock¹

View full text Add to dashboard Cite

Finding and attracting a mate is an enormous component of human life, and indeed the life of all sexually reproducing organisms. In this search, we share many common goals in attaining a partner. For instance, most people typically seek a partner who is kind, attractive, and funny. Yet, we also differ remarkably in the traits that we desire in our partners and what drives us towards choosing some mates over others. This variation represents somewhat of a Darwinian paradox, as selection typically reduces variation in traits under strong selection, such as those relating to mating strategy. To resolve this paradox, evolutionary psychologists have proposed adaptive mechanisms that cause variation in mating strategy in response to environmental contingencies. In this thesis, I present tests of a number of these hypotheses, and integrate approaches from evolutionary behavioural genetics to provide alternative explanations as to how variation in mating strategy arises.Firstly, I review broad evolutionary approaches to explaining variation in psychological traits. Specifically, I introduce evolutionary literature regarding a proposed trade-off between parenting traits and signals of genetic quality in males that permeates approaches to various aspects of mate choice. Evidence for and against this trade-off is reviewed in the context of the maintenance of variation in facial masculinity in males and inter-partner variation in female orgasm frequency during penetrative sex. I then introduce behavioural genetics as an approach to understanding both genetic and environmental causes of variation in human mating strategy.In my first empirical study, I present a paper testing evolutionary hypotheses regarding female variation in orgasm frequency in response to male characteristics. Where previous research has focused on women reporting on a single partner and observing male characteristics across the sample, this paper had females report on partners with whom orgasm was easy and with whom orgasm was difficult. This controls for the possibility of confounds relating to between-subject studies and increases our power to detect male traits associated with orgasm over and above between women differences. Furthermore, the study also included measures of male sexual behaviour, as these are highly likely to be related to female orgasmability. We showed mixed support for evolutionary theories regarding variation in the female orgasm, but were unable to distinguish the two leading hypotheses. Additionally, we found important contributions of male sexual behaviour to female orgasm. Consequently, little can be inferred about the role of variation in the evolution of the female orgasm. However, we demonstrate that within-subjects designs are able to detect between-partner variance with high resolution. We also demonstrate that future studies need account for male sexual behaviour when attempting to explain adaptive variation in female orgasm between different male partners.ii I then present a paper providing evidence that facial ...

show abstract

Are badges of status adaptive in large complex primate groups?

Cited by 84 publications

References 67 publications

Highly polymorphic colour vision in a New World monkey with red facial skin, the bald uakari (Cacajao calvus)

Highly polymorphic colour vision in a New World monkey with red facial skin, the bald uakari (Cacajao calvus)

Beneath the beard: do facial morphometrics influence the strength of judgments of men's beardedness?

Testing Evolutionary Hypotheses Regarding Individual Differences in Human Mating Strategies

Contact Info

Product

Resources

About