Male personality, life-history strategies and reproductive success in a promiscuous mammal


Denis Réale, Département des Sciences Biologiques, CP-8888, succursale centre-ville, Montréal, QC, Canada H3C 3P8.
Tel.: (514) 987 3000 (ext. 2265); fax: (514) 987 4647; e-mail:


Recent theoretical work suggests that personality is a component of life history, but links between personality and either age-dependent reproductive success or life-history strategy are yet to be established. Using quantitative genetic analyses on a long-term pedigree we estimated indices of boldness and docility for 105 bighorn sheep rams (Ovis canadensis), born between 1983 and 1999, and compared these indices to their reproductive history from 2 years of age until death. Docility and boldness were highly heritable and negatively genetically correlated. Docile and bold rams survived longer than indocile and shy rams. Docility and boldness had a weak negative effect on reproductive success early in life, but a strong positive effect on older rams. Our findings highlight an important role of personality on reproductive success and suggest that personality could be an important component of life-history strategy.