Supermodel Iman (center) introduces her husband David Bowie (L) to Rihanna (R) at the DKMS' 5th Annual Gala: Linked Against Leukemia honoring Rihanna & Michael Clinton hosted by Katharina Harf at Cipriani Wall Street on April 28, 2011 in New York City. (Photo by Andrew H. Walker/Getty Images for DKMS)

Christina Careaga (R) and Hannah Thielmann kiss as they celebrate during the Gay Pride parade on June 26, 2011 in New York City. The parade took on extra significance following Friday night's legalization of same-s*x marriage in New York, often regarded as the birthplace of the gay rights movement. (Photo by Mario Tama/Getty Images)

PALEMBANG, SUMATRA, INDONESIA - NOVEMBER 14: Fitriyani Fitriyani (L) of Indonesia and Janice Ng (R) of Singapore compete in the Sport Climbing Womens Speed Track Finals on day four of the 2011 Southeast Asian Games at Jakabaring Sports Complex on November 14, 2011 in Palembang, Sumatra, Indonesia. (Photo by Matt King/Getty Images)

This greedy piglet was isolated from the rest of its litter by the farmer who named it Hitler after it tried to grab all the food at feeding time. (Photo by R J Lewis/Getty Images). 1942

These stunning color portraits, produced by the U.S. Office of War Information during World War II depict the role of women in the US war effort. All of the images were shot on 4x5 color transparency film by Howard R. Hollem and Alfred T. Palmer during 1942 and 1943 and were turned over to the Library of Congress Prints and Photographs Division in 1944. They are seen here with their original captions.

An Israeli boy swims next to sheep belonging to a Palestinian farmer in the West Bank village of Al-Auja in the Jordan Valley on April 8, 2015 during the Jewish Passover holiday. Thousands of Israelis spent the day outdoors, picnicking and touring the country during the eight-day Passover holiday, which commemorates the Israelites' exodus from Egypt some 3,500 years ago. (Photo by Menahem Kahana/AFP Photo)

Alaa, an ambulance driver, feeds cats in Masaken Hanano in Aleppo, September 24, 2014. Alaa buys about $4 of meat everyday to feed about 150 abandoned cats in Masaken Hanano, a neigbourhood in Aleppo that has been abandoned because of shelling from forces loyal to Syria's president Bashar Al-Assad on it. Alaa said that he has been feeding and taking care of the cats for over 2 months. (Photo by Hosam Katan/Reuters)