Trevor Olson, from Minnesota, dressed as the character “Joker”, poses for a photograph at New York's Comic Con convention, October 9, 2014, in New York City. The event draws thousands of costumed fans, panels of pop culture luminaries and features a sprawling floor of vendors in a space equivalent to more than three football fields in Javits Center. (Photo by Shannon Stapleton/Reuters)

“A Mothers Tail”. A baby cub pulls on his mother's tail to get attention. Photo location: Masai Mara, Kenya. (Photo and caption by Tori Marsh/National Geographic Photo Contest)

Rihanna celebrates by flashing the crowd on July 13, 2014 in Rio de Janeiro, Brazil. (Photo by Twitter.com)

In a January 19, 2014 photo Phillip Seymour Hoffman poses for a portrait at The Collective and Gibson Lounge Powered by CEG, during the Sundance Film Festival in Park City, Utah. Hoffman, who won the Oscar for best actor in 2006 for his portrayal of writer Truman Capote in “Capote” was found dead Sunday in his apartment in New York with what law enforcement officials said was a syringe in his arm. He was 46. (Photo by Victoria Will/AP Photo/Invision)

Model Isabeli Fontana poses after the 2014 Victoria's Secret Fashion Show in London December 2, 2014. (Photo by Luke MacGregor/Reuters)

“Just hanging out”. As full autumn hits the valley of Hallingdal in Norway, this bear chills out in a tree which seems to barely cover its weight. Photo location: Flå, Hallingdal, Norway. (Photo and caption by Jorgen Tharaldsen/National Geographic Photo Contest)

“Slow”. A calm cow in the messy streets of Jodhpur. Photo location: India. (Photo and caption by Matthias Troeger/National Geographic Photo Contest)

“The Challenge!” Young boy relishes in a game of tug of war before school. Photo location: Lake Titicaca, Peru. (Photo and caption by Paul Heyman/National Geographic Photo Contest)