A hyena eyes a herd of zebra at Lake Nakuru National Park, Kenya, August 19, 2015. The Park is home to some of the world's most majestic wildlife including lions, rhinos, zebras and flamingos. The scenery is stunning, from forests of acacia trees to animals congregating at the shores to drink. UNESCO says that with rapid population growth nearby, the area is under "considerable threat from surrounding pressures," particularly deforestation, a contributing factor in floods. (Photo by Joe Penney/Reuters)

A Palestinian woman paints a mural, depicting a masked Palestinian holding a knife, in support of Palestinians committing stabbing attacks against Israelis, in Rafah in the southern Gaza Strip November 3, 2015. (Photo by Ibraheem Abu Mustafa/Reuters)

Clowns sit in the pews and hold hands across the aisle of the All Saints Church during the Grimaldi clown service in Dalston, north London, February 7, 2016. The Clowns International 70th annual service brings together professional clowns from Britain and Europe in a service of remembrance to the famous British clown Joseph Grimaldi, who died in 1837. (Photo by Peter Nicholls/Reuters)

An Israeli teenager crawls through mud as he participates in an annual combat fitness training competition, as part of his preparations ahead of his compulsory army service, near Kibbutz Yakum, central Israel February 19, 2016. (Photo by Baz Ratner/Reuters)

“A Little Monkey on the Cliff”. “A cold front hit the Nagano prefecture. I saw a little monkey enduring the cold in Jigokudani Monkey Park. This little monkey is really cute”. (Photo by Hidetoshi Ogata/Smithsonian Photo Contest)

A life-size robot named “Mark 1”, built by product and graphic designer Ricky Ma, 42, is seen in Hong Kong, China March 31, 2016. Ma, a robot enthusiast, spent a year-and-a half and more than HK$400,000 ($51,000) to create the humanoid robot, which is modelled after a Hollywood star, to fulfil his childhood dream. The eyes of the robot include face and color tracking functions. (Photo by Bobby Yip/Reuters)

A policeman reacts during a clash with protestors during a protest against the proposed changes to France's working week and layoff practices, in Lyon, central France, Thursday, April 28, 2016. French protesters are back on the streets over proposed reforms to the country's labor rules and strikers have forced cancellations and delays at two airports serving Paris. (Photo by Laurent Cipriani/AP Photo)

Iraq's second largest city, Mosul, is locked under the rule of extremists from the Islamic State group trying to purge it of everything they see as contradicting their stark vision of Islam. A trove of photographs now housed at the Library of Congress offers a glimpse of a different Mosul – before wars, insurgency, sectarian strife and now radicals' rule. The scenes were taken in the autumn of 1932 by staff from the American Colony Photo Department during a visit to Iraq at the end of the British mandate. (Photo by AP Photo)