Sex and Sexual Selection

These flashcards cover key concepts and definitions related to sexual reproduction and sexual selection as discussed in the lecture.

What is sexual reproduction?

Sexual reproduction is a method of reproduction that involves the combination of genetic material from two individuals, typically resulting in greater genetic diversity.

What is the biggest cost of sexual reproduction?

Asexual females are twice as genetically related to their offspring as are sexual females.

What is the twofold cost of sex?

A male’s only function is to inseminate females, while males never reproduce offspring directly.

What is one way sex can disrupt evolutionary advantages?

Sex can break up favorable gene combinations, creating genetic variation that might not always be beneficial.

List one cost of searching for a mate.

Searching for potential mates requires significant time and energy.

How does courting potential mates add cost?

It takes time and energy for individuals to court potential mates, which can be resource-intensive.

What is a potential cost of focusing on courting mates in the wild?

Individuals may become less vigilant for predators when searching for and courting potential mates.

What is one benefit of sexual reproduction?

Sexual reproduction can purge deleterious mutations, helping to maintain the health of populations.

Explain Muller’s Ratchet in relation to sexual reproduction.

In sexual reproduction, deleterious mutations can be purged over generations, while asexual reproduction can accumulate these mutations.

What does the Fisher-Muller Hypothesis suggest?

Sex accelerates adaptive evolution by allowing beneficial mutations from different individuals to recombine.

What is the Red Queen hypothesis?

Sexual reproduction helps hosts adapt to rapidly evolving pathogens, likened to a genetic arms race.

Define sexual selection.

Sexual selection is a process that depends on the advantage certain individuals have over others of the same sex regarding reproduction.

What are the two types of sexual selection?

Intersexual selection (one sex chooses mates of the other sex) and Intrasexual selection (members of one sex compete for access to mates).

Give an example of intrasexual selection.

Male elephant seals engage in physical battles to gain access to females.

What does the Hamilton-Zuk hypothesis propose about mate choice?

Healthy males can be identified by their coloration, as unhealthy males tend to be drab, which helps females choose mates resistant to parasites.

What is runaway sexual selection?

The process where a trait in males becomes genetically associated with a female's preference for that trait, potentially leading to exaggerated traits.

What is the sensory bias hypothesis?

This hypothesis suggests that females may prefer certain male traits because they are tied to benefits outside of mate choice.

Provide an example of intrasexual selection in grasshoppers.

Large male grasshoppers can be more competitive because they can pull other males away from potential mates.

What can sexual conflict result in?

Sexual conflict can lead to traits in one sex that unintentionally harm the other, such as male honeybee sperm causing temporary blindness in queens.