A competitor shouts as he takes part in the “Tough Guy” adventure race near Wolverhampton, central England, on January 29, 2017. The Tough Guy event, which is being held for the final time in its 30th year, challenges thousands of competitors to run a gruelling course whilst negotiating over 200 obstacles including: water, fire, and tunnels. (Photo by Oli Scarff/AFP Photo)

In this January 29, 2017 photo, musicians perform for dancers on the shores of Lake Titicaca, as they practice before their presentation for the Virgin of Candelaria celebrations in Puno, Peru. Dancers in colorful masks and elaborate costume celebrate the Virgin of Candelaria, patron saint of communities along the shore of Lake Titicaca, in what's considered the largest Catholic festival in the Andes. (Photo by Rodrigo Abd/AP Photo)

Ethnic “Kam” (also known as Dong) women get ready for a traditional wedding ritual known as the “steal the chicken at the drum tower” in a minority Dong village in southwestern Chinese city of Congjiang, Guizhou province, China January 29, 2017. The ceremony held in the ethnic Kam minority village of Gantuan in Guizhou province is based on a tradition dating back some 500 years that was revived and modified in the 1990s for villagers and tourists. (Photo by Tyrone Siu/Reuters)

Volunteers try to keep alive some of the hundreds of stranded pilot whales after one of the country's largest recorded mass whale strandings, in Golden Bay, at the top of New Zealand's south island, February 10, 2017. Volunteers in New Zealand managed to refloat about 100 surviving pilot whales on Saturday, February 11, 2017 and are hoping they will swim back out to sea after more than 400 of the creatures swam aground at a remote beach. (Photo by Ross Wearing/Reuters)

Figures of Francois Fillon (L), former French prime minister, member of The Republicans political party and 2017 presidential candidate of the French centre-right, and French National Front leader Marine Le Pen are paraded through the crowd during the 133rd Carnival parade, the first major event since the city was attacked during Bastille Day celebrations last year in Nice, France, February 11, 2017. (Photo by Eric Gaillard/Reuters)

This watering hole is the social hub of the veldt; the scrubby grasslands that stretch across Namibia. The scorched earth supports sometimes fragile populations of magnificent wildlife – from endangered predators to plentiful herds of game. But these gentle giraffes and elephants need to be careful: lions don’t sleep at night, they hunt! The spectacular starscape above southern Africa is unchanged since explorers first mapped the continent. The photographer, Pietro Olivetta from Italy, said he had to be patient to capture these shots – but it was worth the wait. (Photo by Pietro Olivetta/Caters News)

A “Federahannes”, a jester figure from Rottweil, participates in the “Narrensprung” (jester jump) parade in Rottweil, southern Germany, Monday, February 27, 2016. About 4000 jesters paraded through the city among thousands of spectators. The Rottweil Narrensprung is the highlight of the Swabian-Alemannic Fastnacht and one of the traditional pre-Lenten carnival parades in southwestern Germany. (Photo by Michael Probst/AP Photo)

A U.S. Navy F18 fighter jet takes off from aircraft carrier USS Carl Vinson during a FONOPS (Freedom of Navigation Operation Patrol) in South China Sea, March 3, 2017. The U.S. military took journalists Friday to the carrier on routine patrol off the disputed South China Sea, sending a signal to China and American allies of its resolve to ensure freedom of navigation and overflight in one of the world's security hotspots. (Photo by Erik De Castro/Reuters)