Voters in Ivory Coast cast ballots Saturday to elect a new leader as longtime President Alassane Ouattara seeks a fourth term, while his key contenders were barred from the race. The election is the latest example of aging men continuing to hold power in Africa, which boasts the youngest population in the world. Cameroon’s Paul Biya, 92, Uganda’s Yoweri Museveni, 81, and Equatorial Guinea’s Teodoro Mbasogo, 83, are some other older African leaders still in power.