Why Did Ancient Humans Start Walking on Two Legs?

Why did humans start walking on two legs? It's one of the biggest mysteries in human evolution — and the old "savanna" story you learned in school is mostly wrong. In this video, we break down 6 competing scientific theories for why our ancestors gave up life on four limbs, from fossil evidence millions of years old to the surprising price our bodies still pay for walking upright today. What you'll learn: Why the classic "savanna hypothesis" doesn't match the fossil record The oldest fossil evidence of upright walking (7 million years old) 6 competing theories: feeding, energy efficiency, staying cool, carrying, wading, and intimidation Why walking upright causes back pain, bad knees, and dangerous childbirth How Lucy's 3.2-million-year-old skeleton and footprints prove modern human gait If you enjoyed this deep dive into human evolution, subscribe for more videos exploring where we actually came from. 👍 Like this video if you learned something new 💬 Comment which theory you think is most convincing 🔔 Subscribe for more science & evolution content