As dawn breaks, nine Kenya Wildlife Service rangers dressed in camouflage and brandishing rifles assemble at an airstrip. They are equipped with a Cessna, a helicopter, and a caravan of Toyota Land Cruisers. Their mission: find, tranquilize, and collar Tsavo’s savanna elephants to see how well they traverse a new rail line that has recently split their habitat in two. It is the first time in history that elephants are being collared specifically to study how they interact with human infrastructure.