Northern white rhino
Also called the Northern square-lipped rhino, they used to be found in several East and Central African countries, before going possibly extinct in the wild. The world's last three, a male called Sudan (pictured), his daughter Najin and his granddaughter Fatu, were kept at the Ol Pejeta Conservancy in Kenya. On March 19, 2018, 45-year-old Sudan died from multiple age-related issues, leaving only two females to save the species from going extinct.