Reproductive Isolation Quiz

Types of Reproductive Isolation

• Temporal isolation occurs when two species breed at different times of the day, different seasons, or different years.
• Habitat isolation occurs when two species encounter each other rarely or not at all because they occupy different habitats.
• Behavioral isolation is based on courtship rituals and other behaviors unique to a species.
• Mechanical isolation occurs due to morphological differences preventing successful mating.
• Gametic isolation occurs when the sperm of one species cannot fertilize the eggs of another species.

Postzygotic Barriers

• Hybrid inviability refers to postzygotic barriers that prevent the hybrid zygote from developing into a viable, fertile adult.
• Hybrid sterility refers to hybrids being sterile, even if they are vigorous.
• Hybrid breakdown refers to the phenomenon where first-generation hybrids are fertile, but their offspring of the next generation are feeble or sterile.

Ecological and Genetic Barriers

• Ecological isolation occurs when two species do not encounter each other due to occupying different habitats, but not isolated by physical barriers.
• Genetic incompatibility refers to the phenomenon where genes of different parent species interact and impair the development or survival of hybrids.

Definition and Purpose of Reproductive Isolation

• Reproductive isolation refers to the barriers that prevent interbreeding between different species.
• The purpose of reproductive barriers is to prevent different species from interbreeding and producing hybrid offspring.
• The purpose of reproductive isolation is to maintain the integrity of different species and prevent the loss of genetic adaptations.

Classification and Function of Reproductive Barriers

• Reproductive barriers are classified into two main categories: prezygotic and postzygotic barriers.
• Prezygotic barriers block fertilization from occurring, while postzygotic barriers prevent the development of hybrid offspring.
• The function of prezygotic barriers is to impede different species from attempting to mate.
• The function of reproductive isolation is to hinder fertilization and prevent the production of hybrid offspring.

Examples of Reproductive Barriers

• Different breeding times or seasons are an example of a prezygotic barrier.
• Mechanical isolation is an example of a prezygotic barrier that prevents successful mating.
• Hybrid sterility is an example of a postzygotic barrier that prevents hybrid offspring from reproducing.