This AP® Biology content examines how natural selection, environmental change, and human activities shape the evolution and diversity of populations. Learners will explore the causes of natural selection, how differential survival and reproductive success drive evolutionary change, and why phenotypic variation is essential for adapting to shifting selective pressures. Learners will also investigate convergent evolution and analyze how artificial selection allows humans to influence variation in other organisms. AP® is a registered trademark of the College Board, which has not reviewed this resource.