“The National Portrait Gallery, London's annual photographic portrait prize was established in 2003 as the Schweppes Photographic Portrait Prize. In the years 2006 and 2007 it was referred to simply as the Photographic Portrait Prize, while from 2008 new sponsors have resulted in the name, Taylor Wessing Photographic Portait Prize”. – Wikipedia. Photo: “Tic Tac and Tootsie (twin sisters Carrol and Shelly McKean)”. Taylor Wessing photographic portrait prize 2010. (Photo by Jeffrey Stockbridge)

A devotee offers prayers to the setting sun during the "Chhat" festival at Bagmati river in Kathmandu, Nepal November 17, 2015. Hindus in Nepal celebrate "Chhat", a four-day festival that honours the sun god, by praying at sunrise and sunset, and seek blessings for one's family by giving offerings. (Photo by Navesh Chitrakar/Reuters)

Vendors sell their wares at a parking garage for commercial transports in Obalende district in Nigeria's commercial capital Lagos November 23, 2015. (Photo by Akintunde Akinleye/Reuters)

Chinese artist Kong Ning poses in a costume symbolizing a butterfly, which is decorated with 365 masks on its wings to represent the number of days in a year, during her performance art at the Badaling section of the Great Wall on the outskirts of Beijing January 1, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance art “Hua Die” (transforming into a butterfly) and performed it on the first day of the new year as she hopes that China has clean air for this year. (Photo by Kim Kyung-Hoon/Reuters)

Women carry gas cylinders to fill them at a distribution point in Cairo January 19, 2015. Egypt is going through its worst energy crisis in decades and is seeking fresh sources of natural gas, which powers most of its homes and factories. (Photo by Mohamed Abd El Ghany/Reuters)

A dog swims as a resident navigates his boat in a neighbourhood flooded by the Purus river, which continues to rise from days of heavy rainfall in the region, in Boca do Acre, Amazonas state March 14, 2015. According the state civil defense, more than 20,000 people have been left homeless along the Purus river, where incessant rains have flooded the area and caused the river to burst their banks. (Photo by Bruno Kelly/Reuters)