Natural selection

What is natural selection?

Natural selection is the mechanism Darwin identified for evolution: in any population there is genetic variation; individuals with advantageous traits are more likely to survive and reproduce; their advantageous alleles increase in frequency over generations. The four requirements: variation, heritability, differential survival/reproduction, and time. GCSE and A-Level Biology examine examples including peppered moth industrial melanism, antibiotic resistance in bacteria, and finch beak diversity in the Galápagos.