A man carries his wife on his back as they make their way with their luggage along a flooded tunnel to catch their train, after heavy rainfall hit Jinhua, Zhejiang province, China, July 21, 2015. (Photo by Reuters/China Daily)

Fashionistas pose for photographs in front of a homeless man outside Moynihan Station following a showing of the Rag & Bone Spring/Summer 2013 collection during New York Fashion Week in this September 7, 2012 file photo. (Photo by Lucas Jackson/Reuters)

View of an egg fried on the pavement in Pozo Hondo, Santiago del Estero, Argentina on January 23, 2016, while the real feel was 57 degrees Celsius. Pozo Hondo's Mayor Claudio Nicolau fried an egg on the pavement of the main square of the city Saturday. (Photo by AFP Photo/Stringer)

(L-R) Gigi Hadid and Bella Hadid pose backstage prior to the Victoria's Secret Fashion Show on November 30, 2016 in Paris, France. (Photo by Pascal Le Segretain/Getty Images for Victoria's Secret)

This is the amazing moment a heroic hippo saved a gnu from certain death. After being bitten by a crocodile, the large antelope is seen being dragged slowly under the water. But in a miraculous turn of events, a nearby hippo is seen making its way across the water to help the animal in its hour of need. Photo: One of the biggest hippos protects the gnu as it makes its way back to the shoreline, guarding it from any further attacks. (Photo by Vadim Onishchenko/Caters News)

An Iraqi woman attends a festival commemorating the International Day of Peace in Baghdad, September 21, 2015. (Photo by Thaier al-Sudani/Reuters)

The Economic and Social Research Council (ESRC) has announced the winners of a UK national photography competition in which we challenged young people aged 14–18 for their unique take on society and the social sciences by asking them to take a picture on the theme of “Where Do I Belong?” – ESRC Press Office. Photo: “Society hurts”. (Photo by Grace Ridge/ESRC)