In 2002, I spent 10 days in Kenya. I'll never forget lying in a tent on the Maasai Mara trying to sleep against the awful, blood-curdling roar of lions hunting on the moonlit plains. I would wake every hour, swearing a beast was at my door. Seven years later, a trip to Botswana ended without seeing (or hearing) a single lion, and while the safari was magnificent, something powerful and fearsome was notably absent. It made me wonder: What would Africa be without lions?