A child attends a training session in a swimming pool on July 10, 2007 in Wuhan of Hubei Province, China. (Photo by China Photos/Getty Images)

Horses from the Garrison Savannah, who are involved in celebrations today to mark 50 years of Independence, are washed in the sea first thing in the morning on December 1, 2016 in Bridgetown, Barbados. Prince Harry is visiting the Caribbean marking the 35th Anniversary of Independence in Antigua and Barbuda and the 50th Anniversary of Independence in Barbados and Guyana. (Photo by Chris Jackson/Getty Images)

Daredevil Christopher Gillette writhes around with a huge alligator he has saved from death. He works at a Florida sanctuary that rescues the wild beasts if they stroll into neighbourhoods where residents can legally kill them. To raise cash for the centre at Homestead, staff put on shows to feed and wrestle the alligators. Photographer John Chapa, 41, and girlfriend Adriana Canargo, 30, took these shots. Photo: Assistant photographer Adriana Canargo dives with a wild alligator. (Photo by John Chapa/Barcroft Media)

The images were taken off the coast of Tonga in the South Pacific. Photographer Grant Thomas said: “Through my images I aim to show off the amazing life we have on our planet in hope of inspiring more people to experience it for themselves and, most importantly, care for it”. (Photo by Grant Thomas/Caters News Agency)

These images show the unique bond a group of free divers formed with gigantic sperm whales. Swimming just inches away from the huge mammals, the divers are dwarfed in size, made to look like specks in comparison. The photos were taken by renowned underwater photographers Alexandre Roubaud and Alexandre Voyer, who are based in Paris but travel the world to capture such stunning imagery. Here: a diver with a sperm whales. (Photo by Alexandre Roubaud/Alexandre Voyer/Caters News)

Children attend a swim training session at Hangzhou Chen Jinglun Sport school Natatorium, where Chinese Olympic swimmer Sun Yang and Fu Yuanhui also trained, in Hangzhou, Zhejiang province, China, August 10, 2016. (Photo by Aly Song/Reuters)

A 1964 Amphicar driven by James Spear of Henderson, Nevada is shown on the boat launch after a trip to Hoover Dam during the first Las Vegas Amphicar Swim-in at Lake Mead near Las Vegas, Nevada October 9, 2015. The German-made Amphicar was produced from 1961-1968. (Photo by Steve Marcus/Reuters)

A participant wearing Kokoshnik, the Russian traditional headwear, walks out of the water during winter swimming festival in the town of Podolsk, south of Moscow, Russia January 5, 2017. (Photo by Maxim Shemetov/Reuters)