Exam #2 - Section 2 Evolution

What are the five mechanisms of evolution?

Mutation, gene flow (migration), genetic drift, natural selection, and non-random mating (sexual selection).

What role does mutation play in evolution?

Mutations introduce new genetic variations into a population, serving as the original source of all diversity.

What is gene flow?

The movement of genes between populations through migration, which increases genetic variation within populations.

What is genetic drift?

Random changes in allele frequencies, especially in small populations, that can reduce genetic variation over time.

What is natural selection?

The process by which individuals with advantageous traits survive and reproduce more successfully, increasing those traits in the population.

What is non-random mating (sexual selection)?

When individuals choose mates based on traits, influencing which alleles are passed to the next generation.

What are the molecular origins of mutations?

Mutations result from errors in DNA replication, exposure to mutagens such as radiation or chemicals, or viral insertions.

How do random mutations affect evolution?

They create the raw genetic variation on which natural selection and other mechanisms act.

Why is mutation considered random but evolution not?

Mutations occur by chance, but evolution is the non-random process of certain mutations becoming more common through selection.

How do the five mechanisms of evolution interact?

Together, they alter allele frequencies in populations, driving genetic change and adaptation over generations.