Teeming with images of spectacular underwater scenes from around the world, Call of the Blue is the culmination of a five-year project by the photographer and ocean conservationist Philip Hamilton. This groundbreaking book includes contributions from acclaimed scientists and ocean “guardians”, who reveal what drove them to answer the call of the blue. (Photo by Philip Hamilton/The Guardian)

A swimmer disguised as Superman dives into the lake during the 78th “Coupe de Noel” (Christmas cup) swimming race in the Lake Geneva, on December 18, 2016 in Geneva. More than 1800 participants took part in the event, a 12-meter-long swimming off the Geneva's bank in the 7 degrees Celsius cold water. (Photo by Fabrice Coffrini/AFP Photo)

Most Russians intending to vote for Vladimir Putin in Sunday's election say stability is at the root of their faith in their candidate – though many young voters believe it's time for a change of leader. Putin, 65, is expected to win a fourth term in office with 69 percent of the vote, according to the latest survey by a state-run pollster. Reuters correspondents and photographers who travelled around the country talking to voters ahead of the March 18 election found nothing to contradict expectation of an emphatic Putin victory. (Photo by Anton Vaganov/Reuters)

A Turkana man and a boy carrying a gun look on as a G3 battle rifle hangs from a structure used to dry fish at a fishing camp on the shores of Lake Turkana, some kilometres from Todonyang near the Kenya-Ethiopia border in northwestern Kenya October 12, 2013The Turkana are traditionally nomadic pastoralists, but they have seen the pasture that they need to feed their herds suffer from recurring droughts and many have turned to fishing. However, Lake Turkana is overfished, and scarcity of food and pastureland is fuelling long-standing conflict with Ethiopian indigenous Dhaasanac, who have seen grazing grounds squeezed by large-scale government agricultural schemes in southern Ethiopia. The Dhaasanac now venture ever deeper into Kenyan territory in search of fish and grass, clashing with neighbours. Fighting between the communities has a long history, but the conflict has become ever more fatal as automatic weapons from other regional conflicts seep into the area. While the Turkana region is short of basics like grass and ground-water, it contains other resources including oil reserves and massive, newly discovered underground aquifers. (Photo by Siegfried Modola/Reuters)

Jorge, an immigrant from Mexico, dressed as the Sesame Street character Elmo rests in Times Square, New York July 29, 2014. Elmo and Cookie Monster have long delighted young viewers on TV's “Sesame Street”, but the recent antics of New York street performers dressed as the beloved characters have drawn the ire of city officials and now the show's producers. Sesame Workshop, which owns the rights to Big Bird, Ernie and the assorted puppet monsters on the 45-year-old program, said on July 29, 2014 it was drafting plans to stop performers who dress up as the characters from appearing in Times Square, where they pose for photos with tourists and then demand tips. (Photo by Eduardo Munoz/Reuters)

A handout photo made available by the World Press Photo (WPP) organization on 13 February 2017 shows a picture by Rossiya Segodnya photographer Valery Melnikov that won the Long-Term Projects – First Prize award of the 60th annual World Press Photo Contest, it was announced by the WPP Foundation in Amsterdam, The Netherlands on 13 February 2017. Caption: Civilians escape from a fire at a house destroyed by an air attack in the Luhanskaya village. (Photo by Valery Melnikov/EPA/Rossiya Segodnya/World Press Photo)

In a photo taken on July 6, 2017 soldiers of the Korean People' s Army (KPA) watch a fireworks display as part of celebrations marking the July 4 launch of the Hwasong-14 intercontinental ballistic missile, in Pyongyang Fireworks lit up the sky over Pyongyang' s Juche Tower as North Korea celebrated its launch of intercontinental ballistic missile, a milestone in its decades- long weapons drive. On July 4 – the United States' Independence Day – it launched a Hwasong-14 rocket that analysts and overseas officials said had a range of up to 8,000 kilometres, which would put Alaska and Hawaii within reach. (Photo by Kim Won-Jin/AFP Photo)

This undated handout photo received from the Antarctic Ocean Alliance on October 28, 2016 shows a adelie penguin jumping onto the ice in the Ross Sea in Antarctica. The world's largest marine reserve aimed at protecting the pristine wilderness of Antarctica will be created after a “momentous” agreement was finally reached on October 28, 2016 with Russia dropping its long-held opposition. (Photo by John Weller/AFP Photo/Antarctic Ocean Alliance)