Evolution

Syllabus tag: KCSE | Biology | Form 4 | Topic 2 Evolution

Lesson objectives

By the end of this topic, you should be able to:

• Define evolution and state the evidence supporting it.
• Compare the theories of Lamarck and Darwin.
• Explain natural selection and give observed examples.
• Explain the origin of species and the role of variation.

Summary

Evolution is the gradual change in living organisms over long periods, from simpler ancestral forms. Evidence comes from fossils, comparative anatomy, embryology, geographical distribution and biochemistry. Lamarck proposed inheritance of acquired characters, which is rejected; Darwin proposed natural selection, which is accepted and directly observable in pesticide and antibiotic resistance.