British underwater photographer of the year – winner. “Love Birds” by Grant Thomas (UK). Location: Luss Pier, Loch Lomond, Scotland. Thomas’s initial idea was to frame a split shot of one swan feeding below the surface of the water but when he noticed how comfortable they were around him he was confident, with some patience, he could get that magical shot of the two. (Photo by Grant Thomas/UPY 2018)

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)

The 30th anniversary of the meltdown at the Chernobyl nuclear plant that caused large amounts of radioactive particles to be released into the air will be commemorated on April 26, 2016. Photojournalist Sean Gallup returned to the area to document the lasting effects of the world's worst nuclear power plant accident. Pictured, children's beds are seen in an abandoned kindergarten in Kopachi village located inside the Chernobyl exclusion zone, September 29, 2015, near Chernobyl, Ukraine. (Photo by Sean Gallup/Getty Images)

Residents with faces covered in ash ride on a motorcycle as Mount Sinabung volcano erupts, in Sukandebi village in Karo Regency, Indonesia's North Sumatra province, Indonesia June 13, 2015, in this photo taken by Antara Foto. (Photo by Rony Muharrman/Reuters/Antara Foto)

A protester jumps on the table in front of the European Central Bank President Mario Draghi during a news conference in Frankfurt, Germany April 15, 2015. (Photo by Kai Pfaffenbach/Reuters)

Women balance on a “mikoshi” or portable shrine as people carry it into the sea during a festival to wish for calm waters in the ocean and good fortune in the new year in Oiso, Kanagawa prefecture, west of Tokyo, Japan, January 1, 2016. (Photo by Yuya Shino/Reuters)

Sixty-eight year old cross-country runner Rosie Swale-Pope is interviewed while sitting in her cart, “The Icebird”, in Upperville, Virginia March 13, 2015. Swale-Pope, who is from Great Britain and once ran an unsupported 20,000 mile run around the globe, is currently running across the United States from New York City to San Francisco in support of cancer research. (Photo by Gary Cameron/Reuters)

“These Rajasthani sisters were sitting on the staircase inside their house relaxing and enjoy a cup of masala chai”. (Photo by Firdaus Hadzri/National Geographic Travel Photographer of the Year Contest)