A reef shell lies on a beach as the sun sets on Lady Elliot Island located north-east of the town of Bundaberg in Queensland, Australia, June 10, 2015. UNESCO World Heritage delegates recently snorkelled on Australia’s Great Barrier Reef, thousands of coral reefs, which stretch over 2,000 km off the northeast coast. Surrounded by manta rays, dolphins and reef sharks, their mission was to check the health of the world's largest living ecosystem, which brings in billions of dollars a year in tourism. Some coral has been badly damaged and animal species, including dugong and large green turtles, are threatened. UNESCO will say on Wednesday whether it will place the reef on a list of endangered World Heritage sites, a move the Australian government wants to avoid at all costs, having lobbied hard overseas. Earlier this year, UNESCO said the reef's outlook was “poor”. (Photo by David Gray/Reuters)

Participants re-enact the “Battle of Five Armies” from J.R.R. Tolkien's novel “The Hobbit” in a forest near the town of Doksy, Czech Republic June 6, 2015. According to event organizers, hundreds of enthusiasts dressed as characters such as elves, dwarves, goblins and orcs from the book “The Hobbit” re-enacted the clash. (Photo by David W. Cerny/Reuters)

A competitor tries to swipe away some grease as he slips off the “gostra”, a pole covered in grease, during the celebrations for the religious feast of St Julian, patron of the town of St Julian's, outside Valletta August 30, 2015. In the traditional “gostra”, a game stretching back to the Middle Ages, young men, women and children have to make their way to the top of a pole and try to uproot one of the flags to win prizes. Photo by Darrin Zammit Lupi/Reuters)

Jose, a reveller covered in grease, poses for a photo as he takes part in the annual Cascamorras festival in Baza, southern Spain September 6, 2015. The festival was inspired by a dispute between the town of Baza and Guadix over the possession of an icon of the Virgin of Piedad. The Cascamorras refers to representatives from Guadix, who were sent to Baza to recover the statue. As the Cascamorras had to stay perfectly clean to gain possession of the statue, Baza residents attempt to make them as “dirty” as possible. (Photo by Marcelo del Pozo/Reuters)

This image of a young bareback rider was taken in the village of Palenque de San Basilio, in Colombia’s Bolívar department. Founded by freed slaves in the 17th century, it became the first free town in the Americas, following a decree by the Spanish crown. Most of today’s inhabitants are direct descendants of those slaves and have preserved many of their customs, including their own language, Palenquero. (Photo by Sebastián Suki Beláustegui/The Guardian)

A Palestinian boy takes part in a military-style summer camp being held by the Islamic Jihad movement during the youngsters' summer school vacation in Khan Younes town, in the southern Gaza Strip, 13 July 2016. Thousands of youngsters between the age of six and 16 can participate in the summer camp where they receive military as well as religious training. (Photo by Hatem Omar/EPA)

A monument to the character of Darth Vader from "Star Wars", which was rebuilt from a statue of Soviet state founder Vladimir Lenin, is seen in Odessa, Ukraine, October 23, 2015. The Internet Party of Ukraine's main candidate, a person named for the legendary "Star Wars" villain Darth Vader, campaigned in Odessa, cruising through town on a black van to the sound of Imperial March from "Star Wars" saga. (Photo by Yevgeny Volokin/Reuters)

A man holds a girl as she tries to escape when she realised she is to to be married, about 80 km (50 miles) from the town of Marigat in Baringo County, Kenya, December 7, 2014. As Pokot tradition dictates, the future husband arrived to her family home with a group of men to collect the girl. The men arrived with the last settled dowry of livestock for the girl's family. In this case it was 20 goats, three camels and 10 cows, given during a period of several weeks. (Photo by Siegfried Modola/Reuters)