Meet the star students of orangutan school – the unique rehab centre where orphaned apes are taught how to climb trees and survive in the wild without their mum and dad. (Photo by Caters News)

A woman, covered in mud, dances during the traditional “Bloco da Lama” or “Mud Block” carnival party, in Paraty, Brazil, Saturday, February 14, 2015. Revelers in the seaside colonial town threw themselves into deposits of black, mineral-rich slime, emerging covered head-to-toe in the sludge. Bikinis and trunks disappeared beneath the mud, which highlights both gym-pumped pectorals and beer-fed guts. (Photo by Leo Correa/AP Photo)

Yawalapiti children play during the preparations for the celebration of “quarup”, a ritual held to honor in death a person of great importance to them, in the Xingu National Park, Mato Grosso State, May 7, 2012. (Photo by Ueslei Marcelino/Reuters)

A dancer poses for a photograph as part of the “Dance as Art” photo project in Times Square in New York, on September 22, 2014. (Photo by Carlo Allegri/Reuters)

A child wades through the mud next to a grave inside the flooded cemetery in Los Loros town, April 7, 2015. The death toll from heavy rains and flooding that battered Chile last week has risen to 29, with another 150 still missing, according to authorities. (Photo by Ivan Alvarado/Reuters)

An artist performs with a lion during the presentation of the new international show “Extreme arena” at the Ukrainian National Circus in Kiev, Ukraine, 15 September 2016. The show will be staged from 15 September to 11 December 2016. (Photo by Roman Pilipey/EPA)

Hot air balloons are prepared for a flight as others take off during an international hot air balloon festival at Maayan Harod National park in northern Israel September 30, 2015. (Photo by Baz Ratner/Reuters)