chapter 10

Evolution and natural selection

Charles Darwin published "The Origin of Species" in 1859, based on his observations on a five-year voyage around the world.
His observations in South America and the Galapagos Islands led Darwin to hypothesize about the evolution of species.
Evolution occurs when the allele frequencies in a population change.
Four mechanisms can give rise to evolution .
- mutation
- genetic drift and bottlenecks
- migration and gene flow
- natural selection
Over time, populations evolve and become adapted to their environments.
Evidence for evolution includes:
- Biogeography
- The fossil record
- The anatomical record.
  - vestigial structures
  - homologous structures
  - analogous structures
  - comparative embryology
- The molecular record.
Evolution is a random process and does not yield perfect organisms.