Models sit backstage during Dakar Fashion Week in the Senegalese capital, Friday June 30, 2017. The continent's fashion scene has grown steadily over the past two decades with Sub-Saharan Africa's apparel and footwear market now worth $31 billion, according to data by Euromonitor. (Photo by Finbarr O'Reilly/AP Photo)

Children feeding the birds in this Victorian Christmas greetings card. (Photo by Hulton Archive/Getty Images). Circa 1885

Boys pan for gold on a riverside at Iga Barriere, 25 km (15 miles) from Bunia, in the resource-rich Ituri region of eastern Congo February 16, 2009. Ituri is one of many areas of the country to have experienced bitter ethnic conflict between rival tribes in recent years. Massacres have left tens of thousands dead. It is this fighting that led U.S. authorities to take the unprecedented step of naming Congo in section 1502 of the Dodd-Frank financial regulation act, which says U.S.-listed companies that source gold, tungsten, tantalum and tin from Congo or its neighbours must assure the U.S. stock exchange regulator that their business is not helping fund conflict. (Photo by Finbarr O'Reilly/Reuters)

A young woman employee of North American Aviation Incorporated, working over the landing gear mechanism of a P-51 fighter plane, Inglewood, California, 1942. (Photo by Alfred T. Palmer/Buyenlarge/Getty Images)

(L-R) Singers Kelly Rowland, Beyonce and Michelle Williams perform during the Pepsi Super Bowl XLVII Halftime Show at the Mercedes-Benz Superdome on February 3, 2013 in New Orleans, Louisiana. (Photo by Ezra Shaw/Getty Images)

A giant size figure of the United States' goalkeeper Tim Howard is displayed outside a shopping mall in Hong Kong, Thursday, June 12, 2014, to promote the upcoming 2014 World Cup in Brazil. A total of seven 3.5 meters to 4 meters (11 feet 6 inch to 13 feet one inch) tall figures of famous players attract many soccer fans. (Photo by Vincent Yu/AP Photo)

College students take shelter at a traffic point as a man paddles his rickshaw through a flooded road during heavy rain in Guwahati, India, June 13, 2017. (Photo by Anuwar Hazarika/Reuters)

Children of the Roma community play as they cool off in a fountain in the main square of Pristina, Kosovo on June 14, 2017. (Photo by Armend Nimani/AFP Photo)