This huge male orangutan is having a right old laugh as he squints his eyes and shows his huge teeth. The orangutan, called Bimbo, was relaxing on a platform around 5m high in his enclosure when he broke out into a laugh. But his happy smile soon disappeared when another orangutan came over to see what was going on. Bimbo – the only male in the group of five apes at Leipzig Zoo, in Germany - appears to be laughing in much the same way as a human would. (Photo by Martina Radtke/Solent News)

Hotel staff practice self-defence skills after a training session given by team member of Special Weapons and Tactics (SWAT) team, in Hangzhou, Zhejiang province, April 7, 2016. (Photo by Reuters/Stringer)

A member of the “Sibspas” Siberian search and rescue group dressed as Santa Claus (R), waits for his team mate, dressed as Father Frost, the Russian equivalent of Santa Claus, as he climbs the rock named “The Fourth Stolb” (the Fourth Pillar) at the Stolby national nature reserve during a training session of the Russian Emergencies Ministry, outside the Siberian city of Krasnoyarsk, Russia December 15, 2015. (Photo by Ilya Naymushin/Reuters)

In this photograph taken on June 28, 2015, a hiker in Hong Kong takes a picture of the city from a walking trail. The southern Chinese territory is crisscrossed by more than 180 miles of designated hiking trails. (Photo by Alex Ogle/AFP Photo)

A woman plays with a kitten inside of a line house in downtown Shanghai April 12, 2015. (Photo by Carlos Barria/Reuters)

“Tough Times for Orangutans”. Nature, first prize stories. Tim Laman, USA. Location: West Kalimantan, Indonesia. A Bornean orangutan climbs over 30 meters up a tree in the rain forest of Gunung Palung National Park, West Kalimantan, Indonesia, August 12, 2015. The lives of wild orangutans are brought to light. Threats to these orangutans from fires, the illegal animal trade and loss of habitat due to deforestation have resulted in many orphan orangutans ending up at rehabilitation centers. (Photo by Tim Laman/World Press Photo Contest)

Attnedees dressed in Zombie outfits walk down the Gaslamp Quarter outside of the 2015 Comic-Con International in San Diego, California July 8, 2015. (Photo by Sandy Huffaker/Reuters)

French National Front party deputy Marion Marechal-Le Pen attends the questions to the government session at the National Assembly in Paris April 14, 2015. (Photo by Charles Platiau/Reuters)