Chapter Summary
Evolution is supported by multiple lines of evidence (fossils, anatomy, molecular data, embryology). Mechanisms include natural selection, genetic drift, and speciation. Tools like phylogenetic trees, cladograms, and Hardy–Weinberg make these ideas concrete.
Fossil Evidence
Transitional fossils (e.g., Tiktaalik) show intermediate forms; the fossil record reveals the sequence of life’s history through geologic time.
Key Terms
- Fossil: preserved remains or traces of ancient organisms
- Homology: similarity due to shared ancestry
- Analogy: similarity due to convergent evolution
- Hardy–Weinberg: model for allele frequency stability
- Clade: group of organisms with a common ancestor
- Speciation: formation of new species
Quiz Yourself
1. Which evidence shows developmental similarities before birth?
2. Wings of bats and insects are examples of:
3. Hardy–Weinberg principle requires: