Evolution

Evidence, mechanisms, and processes driving biodiversity

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

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

Quiz Yourself

1. Which evidence shows developmental similarities before birth?




2. Wings of bats and insects are examples of:




3. Hardy–Weinberg principle requires: