“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)

Breath at sunset, captures a sea turtle at a dive site called Black Rock. Kāʻanapali, Hawaiʻi, August 2013. (Photo by Christopher Doherty/Smithsonian.com)

Festival goers splash through a muddy puddle at Worthy Farm in Somerset, on the third day of the Glastonbury music festival June 27, 2014. (Photo by Cathal McNaughton/Reuters)

Stunning images have revealed ice-cool British tourists chilling out inside Europe’s largest glacier – despite being at risk of flooding. The spectacular collection of images show the explorers braving the freezing temperatures to climb, photograph and even abseil down the inside of the icy cliff sides. Another image shows one visitor on his knees appearing to pray next to a water fall of melted ice. Other glistening shots show an adventurer trying to keep warm by a fire whose flames dance beautifully against the glossy roof. (Photo by Einar Runar Sigurdsson/Mediadrumworld.com)

An undated handout picture made available by the Symbio Wildlife Park on 28 November 2016 shows three Pygmy Marmoset monkeys including an adult male, a female juvenile and a four-week-old baby, at the Symbio Wildlife Park in Helensburgh, South of Sydney, New South Wales, Australia. (Photo by EPA/Symbio Wildlife Park)

Indian Air Force personnel parade during the 85th Air Force Day celebrations at Hindon Air Force base in Ghaziabad on October 8, 2017. (Photo by AFP Photo/Stringer)

Ethnic Miao women wearing traditional costumes take part in a parade during the traditional Lusheng (reed-pipe wind instrument) festival in Gulong, Guizhou province, China November 15, 2017. (Photo by Reuters/China Stringer Network)

An undated handout image provided by UNICEF Germany on 20 December 2016 shows the “UNICEF Photo of the Year 2016” by Iranian freelance photographer Arez Ghaderi. Ghaderi won the first prize for his picture of a girl in a makeshift tent city in the Razavi Khorasan province, Iran, it was announced at a ceremony in Berlin, Germany on 20 December 2016. (Photo by Ariz Ghaderi/EPA/UNICEF Deutschland)