A group of costumed fans attend Comic-Con International at San Diego Convention Center on July 12, 2015 in San Diego, California. (Photo by Daniel Knighton/Getty Images)

In this photo taken on Sunday, February 15, 2015 a girl runs away from a “Mamuxarro” during the carnival, in the small town of Unanu, northern Spain. In the northern Spanish ancient village of Unamu, people dress up as “Mamuxarro”, folkloric figures in white with a red sash and a metal mask to cover their faces as they pursue townsfolk with sticks. According to custom, their “victims” (usually young women) must kneel and kiss the mamuxarro’s knee after he makes the sign of the cross on their forehead. (Photo by Alvaro Barrientos/AP Photo)

A handout picture provided by Solar Impulse on 18 March 2015 shows the Swiss solar-powered plane Solar Impulse 2, HB-SIB, taking off with Swiss explorer Andre Borshberg on board for the third leg Ahmedabad to Varanasi, of the Round-The-World, in Ahmedabad, India, 18 March 2015. Swiss explorers Bertrand Piccard and Andre Borschberg attempt to circumnavigate the world flying with an aircraft, with a 72 metres wingspan, powered only by solar energy without a drop of fuel. (Photo by EPA/Solar Impulse)

A visitor holds up her toy bunny to the aquarium glass in front of Aurora the Russian polar bear at the Sao Paulo Aquarium in Sao Paulo, Brazil, Thursday, April 16, 2015. (Photo by Andre Penner/AP Photo)

A model presents a creation from the Jeremy Scott Spring/Summer 2015 collection during New York Fashion Week September 10, 2014. (Photo by Lucas Jackson/Reuters)

Actors dressed up as zombies walk around while posing for photos with passers-by in New York's Times Square on Friday, October 10, 2014 as a promotion for the season premiere of AMC's “The Walking Dead” this Sunday, October 12, 2014. (Photo by Gordon Donovan)

Singer Rihanna poses at amfAR's fifth annual Inspiration Gala in Los Angeles, California October 29, 2014. (Photo by Mario Anzuoni/Reuters)

Rihanna holds the pregnant belly of Spc. Ariel Evans during an event promoting her Rogue Man cologne at Ft. Belvoir Exchange on Wednesday, November 12, 2014 in Ft. Belvoir, Va. (Photo by Kevin Wolf/AP Photo)