Science Spotlights: Why Do We Walk on Two Legs? Ask a Leaf!

Harvard graduate student Ruth Tweedy from the Department of Earth and Planetary Sciences explores why humans walk on two legs while our primate relatives swing through trees. Studying ancient landscapes in eastern Africa, she analyzes the waxy coatings on fossilized leaves—tiny chemical “fingerprints” that reveal what the world looked like millions of years ago. These clues help explain the environments where early humans lived and why standing tall may have been the smartest way to get around. A 20-minute talk will be followed by a 10-minute Q&A. Recommended for ages 10 and up. Regular museum admission rates apply.