Dr. Hannah Cobb from The University of Manchester looks at a viking sword during a viewing at CFA Archaeology of artefacts discovered from the first fully intact Viking boat burial site on October 18, 2011 in Edinburgh, Scotland. (Photo by Jeff J Mitchell/Getty Images)

A British soldier from 3 Commando Brigade looks through the sight of his sniper rifle at Camp Gibraltar February 24, 2003 near Kuwait City, Kuwait. (Photo by Ian Waldie/Getty Images)

Alisa, 10, gets a kiss from one of the wolves her family tamed in the village of Zacherevye, Belarus, on August 17, 2014. (Photo by Sergei Gapon/AFP Photo)

This Sunday, September 7, 2014 photo provided by Rachel Kirk shows smoke from a fire rising above Little Yosemite Valley near Yosemite National Park, Calif. (Photo by Rachel Kirk/AP Photo)

Confiscated weapons hang from a magnet before being destroyed at a foundry in Santiago, Chile, January 18, 2016. Nearly 13,000 firearms were destroyed as part of a government arms control program. (Photo by Ivan Alvarado/Reuters)

An iguana in Bali helped Julij Kopilović, age eight, from Slovenia, earn second runner-up in Amazing Animals. (Photo by Julij Kopilović/National Geographic)

A Free Syrian Army fighter walks past a flag of al-Furqan brigade as a rifle hangs from a branch in the orchards of Kafar Zita in Hama countryside January 22, 2015. (Photo by Mohamad Bayoush/Reuters)

Alicia Vargas, 23, a performer from the Urus Diablada group, tied the laces of her boots before a practice ahead of Carnival in Oruro, Bolivia February 5, 2016. (Photo by David Mercado/Reuters)