Immature Males as Social Commodities: Reproductive Strategies and Hormones as Drivers of Adult Male-Infant Affiliation in Cebus capucinus imitator
Abstract
Adult male white-faced capuchins (Cebus capucinus imitator) actively handle infants. My project investigated: 1) male reproductive strategies (paternal investment, mating effort and alliance formation) as ultimate explanations for why adult males interact affiliatively with infants; and 2) fecal estradiol levels as the possible proximate mechanism. I conducted 10 months of observation on 10 adult males living in 4 habituated groups in Costa Rica, and collected behavioural data to document adult male affiliation patterns. I measured estradiol concentrations in fecal samples to understand the interaction between male-infant affiliation and circulating hormones. Adult males exhibited a sex bias towards male infants, offering support for the alliance formation hypothesis but not the paternal investment and mating effort hypotheses. Fecal estradiol levels were not related to rates of adult male-infant affiliation. I concluded that adult males use infant males as “social commodities” to influence social integration and ultimately increase their future reproductive success.
Description
Keywords
Anthropology--Physical
Citation
Myers, M. (2016). Immature Males as Social Commodities: Reproductive Strategies and Hormones as Drivers of Adult Male-Infant Affiliation in Cebus capucinus imitator (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/26449