An armed man herds his cattle close to the village of Nimini in northern South Sudan, February 8, 2017. In the chaos of South Sudan's civil war, it took three years for Nyagonga Machul to find her lost children. Machul had traveled from her village to the capital when President Salva Kiir, an ethnic Dinka, fired his deputy Riek Machar, a Nuer, in 2013. (Photo by Siegfried Modola/Reuters)

“Leopard Hunting a Stork”. “One-shot capture. I watched the leopard stalking the stork, I only had time to focus at 400mm, no time to change to high speed, I watched the stork, and as soon as it flapped its wings, I shot one shot”. (Photo by Paul Rifkin/National Geographic Travel Photographer of the Year Contest)

A bear that wandered into a University of Colorado Boulder dorm complex falls from a tree after being tranquilized by Colorado wildlife officials on April 26, 2012. Colorado wildlife official Jennifer Churchill said that the 200-pound male bear was tagged and relocated to a remote Rocky Mountain area. The bear was hit by two cars on May 3 and died. (Photo by Andy Duann)

Anti-pollution protesters wearing traditional costumes and contemporary gas masks ride bicycles in the Qingming Grand river park in Kaifeng, Henan Province, China on January 1, 2017. The Beijing Municipal Environmental Protection Bureau extended an “orange alert” for heavy air pollution for three more days. (Photo by SIPA Asia/Rex Features/Shutterstock)

This handout photo taken on February 12, 2017 and released on February 16 by the International Federation of Red Cross and Red Crescent Societies (IFRC) shows Mongolian herder Munkhbat Bazarragchaa (C) dragging two sheep – which recently died due to the weather - to a pile of dead animals behind his “ger” in Khuvsgul province, northern Mongolia. Thousands of Mongolian herders face disastrous livestock losses from dreaded severe weather known as the “dzud”, the Red Cross said on February 16, 2017 in launching an international emergency aid appeal. (Photo by Mirva Helenius/AFP Photo/IFRC)

Waura Indians wrestle during this year's “quarup”, a ritual held over several days to honour in death a person of great importance to them, in Xingu National Park, Mato Grosso State, Brazil August 25, 2013. (Photo by Ueslei Marcelino/Reuters)

This tiny hedgehog is in a prickly position as hes unable to grow spikes, leaving him needing round-the-clock care. The woodland critter was found with no spikes and has been taken in by a family hoping to nurse him back to health so he can be released into the wild. Named Mr Prickleless, the hedgehog was rescued by Dina Nixon and her daughter Jennifer, 25, after being taken into a rescue centre in December last year. It is not known what happened to his spikes, but Dina has vowed that if they ever do return he will be returned to the wild. But for now the hedgehog has taken shelter in a rabbit hutch in her garden. (Photo by Caters News Agency)

A frog sits on a leaf and instead of seeing a reflection of itself in the water below, it sees a snail, attached to the bottom of the leaf, in a fish tank in Vietnam. (Photo by Duong Quoc Dinh/Solent Ne/SIPA Press)