Palestinian boy Mohammad al-Bana, 10, sells mints at a market in Gaza City March 29, 2016. Bana, whose father is unemployed, earns around 10 Shekels ($2.5) per day. The boy starts working after finishing school. He hopes to continue education and become an engineer in the future. (Photo by Mohammed Salem/Reuters)

Female Siberian tiger Dasha yawns in the new enclosure at the zoo in Duisburg, Germany, 30 March 2016. The new facility is three times larger than the old one and will be opened to the public on the same day. (Photo by Roland Weihrauch/EPA)

Boys pose with their toy guns as others play on swings, on the first day of the Muslim holiday of Eid al-Fitr, which marks the end of the holy month of Ramadan, in the government-controlled district of Dwelaa in Damascus, Syria July 6, 2016. (Photo by Omar Sanadiki/Reuters)

Participants react as they climb a greased pole to collect vouchers for gifts during a “Panjat Pinang” event organised in celebration of Indonesia's 71st Independence day in Jakarta, Indonesia August 17, 2016. (Photo by Darren Whiteside/Reuters)

Female metro passengers hold flowers presented to them by metro workers, prior to International Women's Day in Kiev, Ukraine, 02 March 2016. The hustle and bustle of the morning commute is broken up by an unexpected surprise. The first passengers to step on the train receive – a warm welcome and a pot of flowers. One woman says, “It's very nice. All the running around and then you're given a flower, it's not often. It's very nice. I'm going to take care of this flower”. International Women's Day first emerged from the activities of labour movements at the turn of the twentieth century, in North America and across Europe, it is celebrated on March 08 in many countries around the world. (Photo by Sergey Dolzhenko/EPA)

James Castrission, “Cas” and Justin Jones “Jonesy” ski across an ice staking rink with two “You Can” patients on August 2, 2011 in Sydney, Australia. In 75 days, the Aussie adventure pair will attempt to cross 2,200 kilometres of Antarctic ice to the South Pole and back on foot to raise money for youth with cancer. The journey will require the two to trek with all the supplies for approximately three months of walking. Cas and Jonesy became the first to kayak unassisted over 3,300 kilometres from New Zealand to Australia in 2008. (Photo by Ryan Pierse/Getty Images)

Gun enthusiasts look over Smith & Wesson pistols at the NRA Annual Meetings & Exhibits on May 21, 2016 in Louisville, Kentucky. About 80,000 visitors are expected to attend the three-day event. (Photo by Scott Olson/Getty Images)

A woman looks across as a gay parade participant poses for pictures during Gay Pride parade in Madrid, Spain, Saturday, July 2, 2016. Hundreds of thousands of people defied high temperatures and relative security concerns and turned out in Madrid to march in Saturday's LGTB Pride parade, one of the biggest in Europe, along the streets of the Spanish capital, just three weeks after members of the gay, lesbian, bisexual and transgender community were tragically victimized in a shooting massacre at a United States nightclub. (Photo by Daniel Ochoa de Olza/AP Photo)