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)

The main feature of the Mitsuyama Taisai Festival, three 18 meters tall “mountains”. are displayed at the Itate Hyozu Shrine on March 31, 2013 in Himeji, Japan. The festival is held once in 20 years since 1593, Priests of Itate Hyozu Shrine welcome to all the gods across the country for top of the three mountains and treat with food seven days from today as to pray for peace and prosperity. (Photo by Buddhika Weerasinghe)

Russian pop art photographer Sergey Chilikov captures a nation liberated from the social oppression of late-era Soviet rule – at parties, in the streets, and bouncing high. His exhibition, Photoprovocations, will be at Photo London, 19-22 May. Here: Yoshkar-Ola, Matrosova Street (1995). (Photo by Sergey Chilikov)

Residents with their empty containers crowd around a municipal tanker to fetch water in New Delhi, India, February 22, 2016. The Indian army has taken control of a canal that supplies three-fifths of Delhi's water, the state's chief minister said on Monday, raising hope that a water crisis in the metropolis of more than 20 million people can be averted. (Photo by Anindito Mukherjee/Reuters)

A man dressed up as a "Catrin", a Mexican character also known as "The Elegant Death", is pictured during a Catrinas parade in Mexico City October 31, 2015. (Photo by Carlos Jasso/Reuters)

A Syrian youth Khaled from Raqqa walks on snow wearing slippers in the Bekaa Valley refugee camp in Lebanon after the first heavy snow storm hit Lebanon, January 3, 2016. (Photo by Jamal Saidi/Reuters)

In this September 30, 2017 photo, people perform “transvestite target practice” to protest the killings of transvestite prostitutes during the annual LGBQT march in Asuncion, Paraguay. Advocacy groups fear the stigma and attacks against the LGBQT community could get worse now that the country's education minister has banned classes about sexual diversity in schools and even volunteered to help burn all books related to the subject. (Photo by Jorge Saenz/AP Photo)