Unit 2 · 5 lessons
Evolution
How populations change over generations: the evidence for evolution, natural selection and adaptation, the other mechanisms that shift gene pools, and how new species form and old ones disappear.
- 53 practice questions
- 43 flashcards
- 2 interactive lessons
Lessons
- 1The Theory of Evolution and Its EvidenceThe ideas that led to Darwin's theory, why Lamarck's hypothesis was rejected, and the independent lines of evidence (fossils, biogeography, anatomy, embryology and DNA) that support evolution.10 questions
- 2Natural Selection and AdaptationThe four conditions that make natural selection happen, what fitness really means, adaptations including camouflage and mimicry, antibiotic and pesticide resistance, and artificial selection by humans.Interactive11 questions
- 3Mechanisms of Evolutionary ChangeEvolution as a change in allele frequencies, and the mechanisms besides natural selection that cause it: mutation, gene flow, genetic drift (bottleneck and founder effects), sexual selection and non-random mating.11 questions
- 4Selective Breeding: Benefits and Trade-offsHow breeders use variation, selection and inheritance to improve crops and livestock, Canadian examples such as Marquis wheat, canola and Holstein cattle, and the costs: inbreeding depression, monoculture risk and lost genetic diversity.Interactive10 questions
- 5Speciation and ExtinctionWhat makes a species, the prezygotic and postzygotic barriers that keep species apart, allopatric and sympatric speciation, adaptive radiation in Darwin's finches, and why species go extinct.11 questions