Battle-weary American troops withdraw from Yong San in Korea. (Photo by Keystone/Getty Images). 1950

A leopard seal feeds Paul Nicklen a penguin. (Photo by Paul Nicklen/National Geographic). Antarctic Peninsula, 2011

In Omdurman, the largest city in Sudan, the Qadiriyya Sufi order meets every Friday outside Sheikh Hamed Al Nil mosque, which houses the tomb of their 19th century Sufi leader. (Photo by Ala Kheir, John Burns and Ibrahim Algrefwi/Brownbook)

A staff member removes a coffin from a room of the “Corpse Hotel” in Kawasaki, Japan, April 20, 2016. Many so-called corpse hotels have emerged as a flourishing business in the city following a crunch in crematoriums. Families can rent a room in Sousou on a daily charge of 9,000 Japanese yen (£58, €74, $84) to keep the body of the deceased relative for up to four days until they find a crematorium. (Photo by Thomas Peter/Reuters)

Children try to push an injured and weak dolphin back into the water after it washed ashore during bad weather and high tide on a beach in Cilacap, Central Java, Indonesia August 12, 2016 in this photo taken by Antara Foto. (Photo by Idhad Zakaria/Reuters/Antara Foto)

Contestants dance during the Miss Plus Size Carioca beauty pageant on July 8, 2017 in Rio de Janeiro, Brazil. 24 contestants, aged 18-45, competed in the contest which aims to challenge modern inclusive standards of beauty. (Photo by Mario Tama/Getty Images)

The adventurous explorers have snapped themselves in shark-infested waters, at the side of an active volcano, atop a Hong Kong skyscraper surrounded by toxic smog, and even perched on the top of iconic Rio statue of Christ the Redeemer. Here: Ervin Punkar using a selfie stick to take a photo from the very top of the 600ft TV tower in Tartu, Estonia. (Photo by Ervin Punkar/Caters News Agency)

Athletes attend training session at the Ak Bulak Nordic Arena outside Almaty, Kazakhstan, July 16, 2015. Kazakhstan is aspiring to host the 2022 Winter Olympics but many in the Central Asian nation view the bid as yet another vanity project of long-ruling President Nursultan Nazarbayev. Almaty, the financial capital, will go head-to-head with the Chinese metropolis Beijing on Friday when the International Olympic Committee elects the winner at its session in Malaysia. (Photo by Shamil Zhumatov/Reuters)