TOPSHOT - Female Sumatran tiger Mayang's four cubs appear in their enclosure at Berlin's Tierpark zoo on November 22, 2018. - Mayang gave birth to four cubs, two male, two female, named Willi, Oscar, Seri and Kiara, on August 4, 2018. The Sumatran tiger is a rare tiger subspecies that inhabits the Indonesian island of Sumatra and is classified as critically endangered with between 350 to 450 individuals left. (Photo by John MACDOUGALL / AFP)