Internally displaced Syrian children who fled Raqqa city stand near their tent in Ras al-Ain province, Syria January 22, 2017. (Photo by Rodi Said/Reuters)

Competitors release their hens during the World Championship Hen Racing Championships in Bonsall, Britain August 1, 2015. (Photo by Darren Staples/Reuters)

An Afghan refugee girl shows her younger brother a calf in a slum on the outskirts of Islamabad, Pakistan, Friday, February 6, 2015. (Photo by Muhammed Muheisen/AP Photo)

A man smiles as he carries firewood he bought on a street amid ongoing fuel and cooking gas shortages in Yemen's capital Sanaa December 2, 2015. (Photo by Khaled Abdullah/Reuters)

A model poses backstage ahead of the NLP show at Mercedes-Benz Fashion Week Australia 2014 at Carriageworks on April 7, 2014 in Sydney, Australia. (Photo by Brendon Thorne/Getty Images)

This picture taken on July 25, 2014 shows people cooling off in a waterpark in Suining, southwest China's Sichuan province. Meteorological departments issued an orange alert for high temperature as a heat wave embraces Sichuan province, with temperature of most area topped 37, local media reported. (Photo by AFP Photo)

Dutch artist Maxim Gazendam works on his sand sculpture during the third edition of the European Championship Sand Sculpting 2014 in Zandvoort aan Zee, The Netherlands, 08 August 2014. Eight sculptors from different European countries will each create an impressive sculpture on the main theme “Music and Dance”. (Photo by Remko De Waal/EPA)

Children beg for alms in a street on August 11, 2014 in Manila, Philippines. The Philippines has one of the fastest growing populations in Southeast Asia with around 100 million people. At least 12 million people live in the capital city of Manila alone, making it one of the most densely populated and largest cities in the world. Lack of space and economic opportunities has pushed around four million people to live informally along waterways, bridges and even cemeteries further straining the already weak infrastructure and straining the resources of the city. (Photo by Dondi Tawatao/Getty Images)