This lesson plan is part of the lesson plan library for grades 6-8. It focuses on primates (chimpanzees, gorillas, etc.) in the African savannas or grasslands and how they were the first animals in evolutionary history to exhibit bipedalism. Students observe, evaluate, and compare the gaits of humans and primates. They then discuss the possible reasons for such an adaptation. Included are objectives, materials, procedures, discussion questions, evaluation ideas, suggested readings, and vocabulary. There are videos available to order which complement this lesson, an audio-enhanced vocabulary list, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.