Final answer:
Species of primates with little or no sexual dimorphism tend to have egalitarian social structures with less competition and dominance among males. These groups often prioritize cooperation and kinship, as females play central roles alongside males in social organization and mating strategies.
Step-by-step explanation:
If a primate species has little or no sexual dimorphism, we predict that the social group will be more egalitarian and less likely to have a rigid dominance hierarchy. The concept of dimorphism is significant to understanding primate social structures. A high level of sexual dimorphism typically corresponds to societies with a strong male dominance and high competition among males for females. Conversely, species with low sexual dimorphism often exhibit more equal statuses among genders, collaborative social interactions, and potentially monogamous pairings.
For instance, in primate societies with low sexual dimorphism, such as the gibbon species known for monogamy, there is less size difference between males and females, indicating a lesser emphasis on physical competition for mates. Such societies tend to revolve around cooperation and partnership rather than dominance and competition. Thus, lower sexual dimorphism is often correlated with behaviors that support a more equal and peaceful society where the social bond is more frequently based on kinship and solidarity.
This perspective is supported by the research that identifies the importance of both male and female roles in primate social life, where cooperation rather than competition is often the central feature of these societies. This finding contrasts the earlier views which focused on male competition and female passivity, showcasing a more complex and nuanced understanding of primate behavior.