Exploring Sexual Dimorphism: Anthropological Perspectives

Sexual dimorphism can be defined as “morphological differences or varied appearances between males and females within the same species,” stated from Webster’s Dictionary. Anthropologists and primatologists study sexual dimorphism for various reasons depending upon, what information is trying to be uncovered. For example, a forensic anthropologist might use sexual dimorphism to try to nail down traits that will allow easier identification of a sex within skeletal and dental remains (Plavcan, 2001). Alternatively, a primate biologist may focus on understanding the causes of sexual dimorphism in primates, and how these relate to the variation in behaviors and ecological structure (Plavcan, 2001).

While there are various reasons to study sexual

Social groups of primates closely relate to sexual dimorphism, because how each of their communities interact with one another plays a large role in sexual selection. Sexual selection, as Darwin stated, is a key factor and cause in the morphological dimorphism between sexes of a species. Additionally, sexual selection comes from male competition, which directly correlates to primate’s social structures. For example, genus gorilla is a part of a polygynous mating system, which consists of one male and multiple female. This creates an environment where males must compete with one another to reproduce and create offspring. Due to this competition, males must prove to be strong and attract themselves to females to ensure reproductive success. These strong male traits are favored in sexual selection, because the females are highly particular about the male they mate with, so there become specific male traits that are most desirable. Therefore, in polygynous groups, sexual dimorphism is the greatest (Frayer, Wolpoff, 1985). In comparison, a monogamous primate such as genus hylobate or gibbons has a social structure that consists of a more nuclear based family. There is a lot less male competition because males do not mate with multiple females. Therefore, primates are less dimorphic in monogamous social structures (Frayer, Wolpoff,

Importantly, we have discovered that female and male sexes within the same species have varied differences and varied similarities throughout our primate ancestry. This allows for hypotheses and predictions of why evolutionary changes occurred, but there is not one answer to, why we lack that degree of dimorphism, or why another primate has a high degree of dimorphism. While conclusions have been made, the biggest take from all of this is if trends in human evolution continue as they have been, eventually all that may be left is primary sex