Sexual selection and vocalization in humans and nonhuman anthropoid primates

Open Access
- Author:
- Hill, Alexander Kirkland
- Graduate Program:
- Anthropology
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- November 22, 2013
- Committee Members:
- David Andrew Puts, Dissertation Advisor/Co-Advisor
David Andrew Puts, Committee Chair/Co-Chair
Mark Shriver, Committee Member
Nina G Jablonski, Committee Member
Daniel J Weiss, Committee Member
Drew Rendall, Special Member - Keywords:
- Sexual selection
Vocalization
Anthropoids
Evolutionary psychology; Fluctuating asymmetry - Abstract:
- This dissertation consists of three studies focusing on sexual selection and vocalizations. The first study explores the influence of sexual selection on vocalizations in nonhuman anthropoids. Recordings of 1451 vocalizations from 40 species were measured for vocal fundamental frequency (F0), the acoustic correlate of pitch. Data on mating system, habitat, and male and female body size were collected for these species. Controlling for body size sexual dimorphism, we found that males had relatively lower F0 compared to females in polygynous species than in monogamous species, indicating that sexual selection favors lower F0 among anthropoids. The second study focuses on men’s vocal, facial, and body masculinity in order to evaluate the relative influence of individual traits on mating success and the mechanisms, form, and direction of these sexual selective pressures. We ascertained men's dominance and attractiveness from male and female acquaintances. On a large American university campus, 63 men from two social fraternities provided anthropometric measurements, facial photographs, voice recordings, and reported mating success (number of sexual partners). These men assessed each other's dominance, and 72 women from two socially affiliated sororities assessed the men's attractiveness. We measured facial masculinity from inter-landmark distances and vocal masculinity from acoustic parameters. We additionally obtained facial and vocal attractiveness and dominance ratings from unfamiliar observers. Results indicate that dominance and the traits associated with it predict men's mating success, but attractiveness and the traits associated with it do not. The final study concerns relationships between the human voice and fluctuating asymmetry (FA), a putative biomarker for genetic quality. We explored these relationships in three samples representing both US university participants (Study 1: n=91 males; Study 2: n=151 males and 233 females) and Tanzanian hunter-gatherer participants (Study 3: n=51 males and 64 females). Voice recordings were collected and rated for attractiveness, and measures of FA were computed from two- and three-dimensional facial images, as well as finger lengths. Only among Study 2 females did we observe the previously-documented negative relationship between vocal attractiveness and FA as measured from two-dimensional facial imagery. No relationship was found between vocal attractiveness and three-dimensional FA.