Sexual size dimorphism in bighorn sheep (Ovis canadensis): effects of population density

摘要: Sexual dimorphism is an important characteristic of many mammals, but little known about how environmental variables may affect its phenotypic expression. The relationships between population size, body mass, seasonal mass changes, and sexual were investigated using 22 years data on individually marked bighorn sheep (Ovis canadensis) Ram Mountain, Alberta. number adult ewes was artificially maintained low from 1972 to 1981 then allowed increase. males 0 7 age negatively affected by density. Female density up 2 age. As the increased, aged 2–7 declined. Population had a negative effect changes young females. Density also weak significant positive yearly gain 2-year-old females, suggesting compensatory growth. Females appear compensate for res...