Members of the Indian Border Security Force (BSF) demonstrate their skills on motor-bikes during the BSF Golden Jubilee Day celebration in New Delhi on December 1, 2015. (Photo by Money Sharma/AFP Photo)

A Naga sadhu, or naked Hindu holy man, performs a ritual inside his tent during Kumbh Mela, or Pitcher festival, at Trimbakeshwar, India, Friday, August 28, 2015. Hindus believe taking a dip in the waters of a holy river during the festival will cleanse them of their sins. The festival is held four times every 12 years. (Photo by Rajanish Kakade/AP Photo)

Robot couple Xiaolan (L) and Xiaotao carry trays of food at a restaurant in Jinhua, Zhejiang province, China, May 18, 2015. The restaurant, which opened on Monday, has two robots delivering food for customers. The robots were designed as a couple, Xiaolan and Xiaotao, according to local media. (Photo by Reuters/Stringer)

Actress Bai Ling poses for a picture in front of St. Basil's Cathedral at the Red Square in Moscow, Russia, July 1, 2015. (Photo by Ivan Burnyashev/Reuters)

These stunning pictures show a normally vicious tiger calmly swimming in a pool of algae, on Jule 9, 2014. The powerful cat takes a refreshing break by taking a dip in the bright green algae. But it looks like this big cat is scared of getting his head wet as he strains to keep it above the water. After splashing around for a bit the tiger gets out and tries to air-dry with specks of the vegetation dripping off his fur. The striking pictures were taken at Copenhagen zoo by snapper Soren Lundgren Neilson. (Photo by Soren Nielsen/Caters News)

In this Thursday, April 16, 2015 photo provided by Robert MacFarlane, a raccoon climbs up a skyscraper in downtown Toronto. Social media was abuzz Thursday with the photo of the raccoon peering from between the metallic rungs of a crane 58 stories high. (Photo by Robert MacFarlane)

Nigerian fashion models are made up for their fashion show to promote ethnic fashion June 13, 2006 in Tel Aviv, Israel. The models said they hope to use the travelling show as a springboard to international fame, in the words of one, “to be the next Naomi Campbell”. (Photo by Uriel Sinai/Getty Images)

Participants ride horses, hold spears and wear historic armoured suits of the Middle Ages as they compete during the Saint George international knight tournament in Moscow, Russia, May 3, 2015. (Photo by Maxim Zmeyev/Reuters)