Cemetery workers repaint tombs inside the municipal cemetery in Navotas city, north of Manila October 29, 2015. Filipinos are preparing to celebrate All Saints Day on November 1 by visiting the graves of their departed loved ones. (Photo by Ezra Acayan/Reuters)

A trader weighs tobacco at a market in el-Fasher, in North Darfur February 5, 2015. Tobacco is one of the North Darfur war zone's main cash crops. (Photo by Mohamed Nureldin Abdallah/Reuters)

Ryo Minemizu, one of Japan’s emerging stars in the field of marine life photography and the 2017 winner of the Nikkei National Geographic photography prize, captures the beauty and complexity of plankton that drift in our planet’s oceans and other bodies of water in meticulous detail. Here: Batesian mimicry by a Soleichthys fish larva. (Photo by Ryo Minemizu/The Guardian)

A Tibetan pilgrim prostrates herself at the Jokhang Temple in central Lhasa, Tibet Autonomous Region, China early November 20, 2015. Every day thousands of Tibetans visit and pray at Jokhang Temple, considered one of the most sacred places of worship. (Photo by Damir Sagolj/Reuters)

A fire engulfs The Address Hotel in downtown Dubai in the United Arab Emirates December 31, 2015. Fire engulfed a luxury building near the world’s tallest skyscraper in Dubai on Thursday as tens of thousands of people were gathering at its base for one of the world’s largest New Year’s fireworks displays. (Photo by Ahmed Jadallah/Reuters)

Roof-topping enthusiast Daniel Lau takes a selfie with high-rise buildings down below as he stands on the top of a skyscraper in Hong Kong, China on August 15, 2017. A craze that began in Russia has now taken hold in Hong Kong, one of the world's most vertical cities. Mr Lau said he had been inspired by Russian climbers and that he was unafraid of the vertiginous heights he scales. (Photo by ImagineChina/Rex Features/Shutterstock)

A pigeon, known as Siyah Kinifirli, with an approximate market value of 1000 Turkish Lira ($263), bred by 23-year-old Ismail Ozbek, is pictured in Sanliurfa, Turkey, December 23, 2016. As night-time approaches in Sanliurfa, southeastern Turkey, most of the alleyways of the city's old bazaar are emptying out of buyers and vendors, except for one. (Photo by Umit Bektas/Reuters)

In this Tuesday, May 3, 2016 photo, Madeley Vasquez, 16, breast feeds her one-year-old son Joangel as she waits in line outside a supermarket to buy food in Caracas, Venezuela. Vasquez once ran down the block to avoid getting caught up in a knife fight that broke out when a woman was accused of cutting the line. (Photo by Ariana Cubillos/AP Photo)