Hundreds of hardy swimmers across Britain braved jumping into freezing cold waters for a annual Christmas Day dip on December 25, 2017. (Photo by Dave Nelson/The Sun)

A Russian Sukhoi Su-25 fighter jet takes off during the withdrawal of Russian troops from Syria at Hmeymim airbase, Syria, March 16, 2016. (Photo by Vadim Grishankin/Reuters/Russian Ministry of Defence)

Decorated eggs are seen at the egg museum in Winden am See, Austria, March 25, 2016. The collection of Austrian artist Wander Bertoni contains about 4000 eggs. (Photo by Christian Bruna/EPA)

Workers hold an 80 Kg Paiche (Arapaima gigas) to return it to a pool at a breeding farm in Nueva Loja, Ecuador, March 25, 2016. (Photo by Guillermo Granja/Reuters)

A newly born Indian white tiger cub yawns in its enclosure at Liberec Zoo, Czech Republic, April 25, 2016. (Photo by David W. Cerny/Reuters)

A protester reacts as police use water cannon during a demonstration to demand changes in the Chilean education system in Santiago, Chile June 25, 2015. (Photo by Ueslei Marcelino/Reuters)

An aerial view of the Grand Mosque is seen on the second day of Eid al-Adha, during the annual haj pilgrimage in the holy city of Mecca September 25, 2015. (Photo by Ahmad Masood/Reuters)

A giant river otter, the world's largest otter species, looks out of its enclosure at the newly completed River Safari in Singapore, on March 25, 2013. (Photo by Wong Maye-E/Associated Press)