A garbage collector looks for recyclable waste at a dump in Erbil, in Iraq's northern autonomous Kurdistan region, February 21, 2016. (Photo by Azad Lashkari/Reuters)

Belly dancer Nagwa Fouad sailing on the river Nile, 1972. Egypt is one of 23 countries represented at the Dubai Photo Exhibition, showing off photography that dates to the 1920s. Dubai Photo Exhibition is in various venues of Dubai’s design district from 16-19 March. (Photo by Farouk Ibrahim)

Machu Picchu, Peru. A llama’s-eye view of the legendary Inca settlement at Machu Picchu, isolated high in the Peruvian Andes. (Photo by Jim Turner/National Geographic)

A homeless man rests on the side of a street at the old quarter of Yemen's capital Sanaa November 27, 2015. (Photo by Khaled Abdullah/Reuters)

Some of the most powerful narratives of the past decade have been produced by a forward-thinking generation of women photojournalists as different as the places and the subjects they have covered. National Geographic's “Women of Vision” exhibit features the work of 11 photographers and is on display at the Fernbank Museum of Natural History in Atlanta until January 3, 2016. Here: Nujood Ali stunned the world in 2008 by obtaining a divorce at age 10 in Yemen, striking a blow against forced marriage. (Photo by Stephanie Sinclair/National Geographic)

Actors perform the living Nativity biblical scenes in Postojna cave in Postojna, Slovenia, December 22, 2015. (Photo by Srdjan Zivulovic/Reuters)

Head of the department of the interior architecture at Estonian Academy of Arts Hannes Praks poses for a picture in the wooden megaphone in the forest near Pahni village, Estonia, September 28, 2015. (Photo by Ints Kalnins/Reuters)

A reveller reacts during a water fight at Songkran Festival celebrations in Bangkok April 13, 2016. The three-day Songkran Festival starts on 13-15 April annually and is celebrated with splashing water and putting powder on each others faces as a symbolic sign of cleansing and washing away the sins from the old year. (Photo by Jorge Silva/Reuters)