Biological Anthropology

study guides for every class

that actually explain what's on your next test

Intersexual selection

from class:

Biological Anthropology

Definition

Intersexual selection is a type of sexual selection where individuals of one sex (typically females) choose mates based on specific traits or characteristics that they find attractive. This process leads to the evolution of features in males, such as bright colors or elaborate displays, which can increase their chances of being selected by females. The preferences of one sex drive the evolutionary changes in the other, shaping mating systems and reproductive strategies within a population.

congrats on reading the definition of Intersexual selection. now let's actually learn it.

ok, let's learn stuff

5 Must Know Facts For Your Next Test

  1. Intersexual selection often leads to the development of elaborate courtship behaviors and physical traits that are attractive to the opposite sex.
  2. Females may choose mates based on indicators of genetic fitness, health, or resources that can benefit offspring, which influences the overall genetic quality of the population.
  3. This type of selection can create a 'runaway' effect where certain traits become exaggerated over generations due to continuous preference by females.
  4. The preferences shown by females can vary greatly among species, leading to diverse mating systems such as monogamy, polygyny, or polyandry.
  5. Intersexual selection can significantly impact male competition and behaviors as they adapt their strategies to attract female attention and improve reproductive success.

Review Questions

  • How does intersexual selection influence the evolution of traits in males?
    • Intersexual selection influences male trait evolution by promoting features that are preferred by females during mate selection. As females consistently choose mates based on specific traits, such as bright colors or elaborate courtship displays, these traits become more pronounced over generations. This process drives the development of sexual dimorphism and can lead to extreme adaptations that enhance male attractiveness while also indicating their genetic fitness.
  • Discuss the relationship between intersexual selection and mating systems in different species.
    • Intersexual selection plays a crucial role in shaping various mating systems across species. In species where females exhibit strong mate choice, we often see polygynous systems where males with desirable traits have multiple female partners. Conversely, in monogamous species, both sexes may invest equally in offspring, and female choice can focus more on male parental investment rather than solely on physical attributes. Understanding how intersexual selection operates helps explain the diversity of reproductive strategies observed in nature.
  • Evaluate the implications of intersexual selection on the genetic diversity within a population.
    • Intersexual selection can significantly affect genetic diversity within a population by influencing mate choice and breeding patterns. When females preferentially select mates based on certain traits, it can lead to an increase in specific alleles associated with those traits, potentially reducing genetic variability if those traits become overly dominant. However, if female preferences are flexible or vary over time due to environmental changes, it can promote greater genetic diversity by allowing different male phenotypes to gain reproductive success at different times. Thus, intersexual selection creates a dynamic interplay between attraction and genetic health within populations.

"Intersexual selection" also found in:

© 2024 Fiveable Inc. All rights reserved.
AP® and SAT® are trademarks registered by the College Board, which is not affiliated with, and does not endorse this website.
Glossary
Guides