Kenyan Cabinet Secretary for Tourism and Wildlife Najib Balala (3rd L, front) unveils the tombstone of Sudan, the late world's only remaining male northern white rhino, in Ol Pejeta Conservancy in Laikipia county, northern Kenya, March 31, 2018. Kenyan wildlife officials and global wildlife conservationists on Saturday converged at Ol Pejeta Conservancy in northern Kenya where a memorial service for the late world's only remaining male northern white rhino fondly named Sudan took place. (Xinhua/Lyu Shuai)
