Sexual Dimorphism

Definition

Sexual dimorphism refers to the distinct physical differences between males and females of the same species. These differences can manifest in various aspects of an organism's anatomy, physiology, and behavior, often reflecting the evolutionary adaptations related to reproduction and survival.

5 Must Know Facts For Your Next Test

1. Sexual dimorphism is often more pronounced in species with polygynous mating systems, where males compete for access to multiple females.
2. Differences in body size, coloration, and the development of secondary sexual characteristics are common examples of sexual dimorphism.
3. The degree of sexual dimorphism can vary widely across different species and is influenced by factors such as habitat, resource availability, and the intensity of sexual selection.
4. In humans, sexual dimorphism is evident in differences in height, weight, body composition, and the development of secondary sexual characteristics like facial hair and breasts.
5. Intersexuality, a condition where an individual's biological sex characteristics do not fit the typical definitions of male or female, challenges the binary view of sex and gender.

Review Questions

• Explain how sexual dimorphism is related to the topic of 'Our Ancient Past: The Earliest Hominins'.
  • Sexual dimorphism is an important concept in the study of our ancient past and the earliest hominins. Differences in physical characteristics between male and female hominins, such as body size and the development of secondary sexual characteristics, can provide insights into the social structure, mating systems, and evolutionary adaptations of these early human ancestors. Examining the degree of sexual dimorphism in fossil remains can help anthropologists understand the selective pressures and ecological factors that shaped the evolution of our species.
• Analyze the relationship between sexual dimorphism and the topic of 'Sex, Gender, and Sexuality in Anthropology'.
  • The study of sexual dimorphism is closely linked to the anthropological understanding of sex, gender, and sexuality. Sexual dimorphism reflects the biological differences between males and females, but these differences are also culturally and socially constructed in various ways. Anthropologists explore how the concept of sexual dimorphism intersects with societal norms, gender roles, and the diversity of human sexual and gender expression. This includes examining how the perception and interpretation of sexual dimorphism can influence cultural attitudes, power dynamics, and the lived experiences of individuals within a given society.
• Evaluate how the study of sexual dimorphism can contribute to our understanding of the evolution of human behavior and social structures.
  • The study of sexual dimorphism in human evolution can provide valuable insights into the evolution of human behavior and social structures. Differences in physical characteristics between males and females, such as body size and the development of secondary sexual characteristics, may have influenced the division of labor, resource acquisition, and mating strategies within early human societies. Analyzing the degree of sexual dimorphism in fossil remains can help anthropologists reconstruct the social dynamics and reproductive patterns of our ancestors, shedding light on the selective pressures and ecological factors that shaped the emergence of complex human behaviors and social organizations over time.

Related terms

Intersexuality: A condition in which an individual's biological sex characteristics do not fit the typical definitions of male or female, due to genetic, hormonal, or anatomical variations.

Sexual Selection: The process by which certain traits are favored in one sex over the other, leading to the development of distinct physical and behavioral characteristics between males and females.

Polygyny:

A mating system in which a male mates with multiple females, while a female mates with only one male.