A hippopotamus performs during a show at the circus in Krasnoyarsk, Siberia, Russia, July 7, 2016. (Photo by Ilya Naymushin/Reuters)

A woman controls a ball on Ipanema beach in Rio de Janeiro, Brazil, April 14, 2016. As hundreds of thousands of tourists begin descending on Rio de Janeiro for the Olympics that start August 5, the headlines have focused on the street violence, the Zika virus, the water pollution and the rush to finish venues and transport. But Rio, known by Brazilians as the “Marvelous City”, glistens despite it all. The beach is a way of life here. (Photo by Nacho Doce/Reuters)

German troops in Stalingrad, USSR. September 10, 1942. (Photo by TASS)

Senior Buddhist monk Lobsang Tayang sits outside the Amarbayasgalant Monastery in the Baruunburen district, Selenge province, Mongolia, April 26, 2018. (Photo by Thomas Peter/Reuters)

Two Girls who managed to evade the police walk away as police on foot and horseback push back to te curd at Park Row, In New York on April 26, 1960, A milling throng of more than 1,000 High students who storned city hall in a Demonstration supporting teachers wage demands. (Photo by AP Photo)

A cow is seen on land that used to be under water, at the Aculeo Lagoon in Paine, Chile, May 14, 2018. (Photo by Matias Delacroix/Reuters)

A child performs opera during celebrations on the eight day of Chinese Lunar New Year of the Pig, in Taizhou, Zhejiang province, China on February 12, 2019. (Photo by Reuters/China Stringer Network)

Team Alberta skip Kevin Koe makes a shot during the 10th draw against team British Columbia at the Brier curling tournament in Brandon, Manitoba, Tuesday, March, 5, 2019. (Photo by Jonathan Hayward/The Canadian Press via AP Photo)