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)

In this January 7, 2016, photo, conservationists of Borneo Orangutan Survival Foundation hold a baby orangutan rescued along with its mother during a rescue and release operation for orangutans trapped in a swath of jungle in Sungai Mangkutub, Central Kalimantan, Indonesia. Last year's forest fires drove orangutans closer to the river bank, where they had to live in an over-populated swath of forest as thin as 30 meters wide along the river. (Photo by Dita Alangkara/AP Photo)

Children walk past the partially collapsed boundary wall of a school and a Buddhist shrine that were damaged during the earthquake earlier this year at Khumjung, a typical Sherpa village in Solukhumbu district also known as the Everest region, in this picture taken November 30, 2015. (Photo by Navesh Chitrakar/Reuters)

A Miniature Dachshund (L) wears a duck bill-shaped dog muzzle while sitting in a stroller with another Miniature Dachshund at the “Interpets” international pet fair in Tokyo, Japan, April 2, 2015. (Photo by Kiyoshi Ota/EPA)

A Christian pilgrim is baptised by a priest in the muddy water of the Jordan River at the Kasser-Al-Yahud baptismal site near the West Bank city of Jericho, on April 11, 2017. According to the gospels Jesus Christ was baptised in the waters of the Jordan River by John the Baptist. (Photo by Gali Tibbon/AFP Photo)

The six-months-old female koala cub holds on to the back of zoo keeper Lena at the zoo in Duisburg, Germany, 23 October 2015. The yet unnamed baby weighs 580 grams. (Photo by Roland Weihrauch/EPA)

A hyena eyes a herd of zebra at Lake Nakuru National Park, Kenya, August 19, 2015. The Park is home to some of the world's most majestic wildlife including lions, rhinos, zebras and flamingos. The scenery is stunning, from forests of acacia trees to animals congregating at the shores to drink. UNESCO says that with rapid population growth nearby, the area is under "considerable threat from surrounding pressures," particularly deforestation, a contributing factor in floods. (Photo by Joe Penney/Reuters)

5-year-old Rina Kumari rubs her eye while cracking stones on the banks of Mahananda river in Siliguri, northeast India, March 5, 2005. Over 400 million people in India live below the internationally agreed poverty line (living on less than US $1 per day). According to estimates, several hundred thousand children work as labourers and beg on the streets in India. (Photo by Desmond Boylan/Reuters)