American Paralympic snowboarder Amy Purdy dances with a robot during the opening ceremony of the Rio 2016 Paralympic Games at the Maracana stadium in Rio de Janeiro on September 7, 2016. (Photo by Yasuyoshi Chiba/AFP Photo)

A newly born Indian white tiger cub yawns in its enclosure at Liberec Zoo, Czech Republic, April 25, 2016. (Photo by David W. Cerny/Reuters)

Fireworks explode over the Quadriga statue atop the Brandenburg Gate on New Year's Eve on January 1, 2012 in Berlin, Germany. According to the media, up to one million people celebrate the country's biggest New Year's Eve Party. (Photo by Andreas Rentz/Getty Images)

New Year's Eve fireworks display illuminates the sky over the Dom Tower on January 01, 2012 in Utrecht, Netherlands. The Dom tower is with 112.5 metres high the tallest church tower of the Netherlands. Built in Gothic-style, the tower, part of the Cathedral of Saint Martin, is the symbol of the city of Utrecht. (Photo by Jasper Juinen/Getty Images)

Martin Garwood prepares to release baby penguins at Sydney Aquarium on January 18, 2012 in Sydney, Australia. Three baby penguins were released into the aquarium and reunited with their parents for the first time since birth. (Photo by Lisa Maree Williams/Getty Images)

South Korean singer CL performs during the closing ceremony of the 2018 Winter Olympics in Pyeongchang, South Korea, Sunday, February 25, 2018, after 17 days of hard- fought competition. Olympic fire went out. (Photo by Natacha Pisarenko/AP Photo)

Bavarian farmers load their cows on a boat before they drive over the picturesque Lake Koenigssee, Germany, October 3, 2015. Before the winter season approaches the farmers have to drive their cattle down from their Alpine meadows to a narrow valley that can only be reached by boat. (Photo by Michael Dalder/Reuters)

Bulgarian Muslims Azim Liumankov and his bride Fikrie Bindzheva pose in front of their house during their wedding ceremony in the village of Ribnovo, in the Rhodope Mountains, February 15, 2015. The remote mountain village of Ribnovo in southwest Bulgaria has kept its traditional winter marriage ceremony alive despite decades of Communist persecution, followed by poverty that forced many men to seek work abroad. (Photo by Stoyan Nenov/Reuters)