Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.Two male lions became infamous for terrorizing and eating humans in 1898 during construction of a railway bridge over the Tsavo River in Kenya. Now, an innovative genetic analysis of hairs trapped inside the cavities of their broken teeth have revealed new insights into the prey the so-called Tsavo man-eaters once hunted.The harrowing true story of the lions, which raided tents in the camp at night and dragged victims into the thicket, has inspired movies and books over the years -- and copious research to understand what drove them to prey on humans.The lions killed at least 28 people, including those working on the Kenya-Uganda Railway, beginning in April 1898 before civil engineer Lt. Col. John Henry Patterson shot the massive cats. Patterson then sold the lions' remains in 1925 to Chicago's Field Museum of Natural History, where they have since remained.Thomas Gnoske, a collections manager at the museum, first spotted thousands of hairs trapped within the lions' teeth when he examined their skulls in the 1990s.Now, Gnoske and his colleagues in Kenya, at the Field Museum and the University of Illinois Urbana-Champaign have been able to isolate single hairs and c ...