Why Did Sex Evolve?

These flashcards cover fundamental concepts related to the evolution of sexual reproduction and its advantages and disadvantages.

Reproductive Handicap

The concept that sexual reproduction is less fit due to requiring two parents and producing fewer offspring than asexual reproduction.

Pros of Sexual Reproduction

Increased genetic variation and the ability to eliminate deleterious mutations.

Cons of Sexual Reproduction

Only half the population can reproduce; offspring inherit only a portion of genes; generally higher risks such as predation and sexually transmitted infections.

Independent Assortment

The process that increases genetic variation by randomly distributing paternal and maternal chromosomes into gametes.

Crossing Over

The exchange of genetic material between homologous chromosomes during meiosis that leads to genetic diversity.

Random Fertilization

The process by which any sperm from a male can fertilize any egg from a female, leading to unique genetic combinations.

Hermaphrodite

An organism capable of producing both eggs and sperm, allowing for a flexible reproductive strategy.

Trematodes as a Selective Pressure

Parasitic worms that can reduce the reproductive success of their snail hosts, affecting the evolution of reproduction strategies.

Red Queen Hypothesis

The evolutionary hypothesis that sexual reproduction provides genetic variation necessary for host adaptation against coevolving parasites.

C-fern Life Cycle

A model organism (Ceratopteris richardii) used to study sexual reproduction and gametophyte interactions.

Self-fertilization

A form of reproduction in which hermaphrodites fertilize their own eggs, can be considered a form of sexual reproduction.