In this May 4, 2014 photo, a miner holds an amalgam of mercury and gold he mined after working a 28-hour shift at an illegal gold mining process, in La Pampa, in Peru's Madre de Dios region. Thousands of artisanal gold miners sweat through the long shifts and endure, for a few grams of gold, the perils of collapsing earth, limb-crushing machinery and the toxic mercury used to bind gold flecks. (Photo by Rodrigo Abd/AP Photo)

Aquarium visitors attend a dinner party in an underwater tunnel in Tianjin, China on September 15, 2016. Tianjin Haichang Polar Ocean World opened in the city of Tianjin, southeast of Beijing, in 2010. It gives visitors a chance to see more than 150 large animals from the Arctic and Antarctic regions, including polar bears. (Photo by Feature China/Barcroft Images)

A undated handout image provided by the Bochum University of Applied Sciences (Hochschule Bochum) on 04 October 2013 shows the German team Bochum's Cruiser class solar car during a test drive in the Northern Territoty, Australia, 16 September 2013. The Dutch vehicle is competing in the World Solar Challenge, driving from Darwin to Adelaide starting on 06 October 2013. (Photo by Hochschule Bochum/EPA)

Some Iraqi candidates for Miss Iraq beauty contest pose in front of the Ishtar Gate at the ancient archaeological site of Babylon, outside the modern city of Hilla, south of the capital Baghdad on December 17, 2015. The beauty contest, which is the first one in more than 40 years, aims to boost tourism in the city and will take place on December 19, 2015. (Photo by Ahmad Al-Rubaye/AFP Photo)

A man passes by an unfinished street art graffiti made in a stairway by French street artists Zag and Sia in Paris on March 1, 2016. The two artists drew inspiration from famous “Liberty Leading the People” (La Liberte guidant le peuple) painting by French Eugene Delacroix commemorating the July Revolution of 1830 and viewed as a symbol of the French Republic. (Photo by Joel Saget/AFP Photo)

“Eye of the Tower” by Mehmet Yasa; Verona, Italy. “The staircase and the bell looks like an eye. Architecture can fascinate us in many ways”. (Photo by Mehmet Yasa/Art of Building Photography Awards 2017)

Kazakh nomads have been grazing their livestock in Mongolia for hundreds of years. Fascinated by the bond between hunter and eagle, photographer Palani Mohan has spent the last few years documenting the burkitshi. Mohan's photos of the landscape, isolation of the hunt, and most of all the trusting relationship between man and bird, convey the importance that the eagle plays in their lives. (Photo by Palani Mohan)

A boy runs with a burning barrel soaked in tar at the annual Ottery St Mary tar barrel festival on November 5, 2015 in Ottery St. Mary, England. The tradition, which is over 400 years old, sees competitors (who must have been born in the town to take part) running with burning barrels on their backs through the village, until the heat becomes too unbearable or the barrel breaks down, starting with junior barrels carried by children and continuing all evening with ever larger and larger barrels. The event, which has been threatened with closure on previous years due to increasing public liability insurance costs, raises thousands of pounds for charity and attracts spectators from around the world. (Photo by Matt Cardy/Getty Images)