Travis Gerrits of Canada competes during qualifying for the Mens Aerials at the FIS Freestyle Ski World Cup Aerial Competition at Deer Valley on January 10, 2014 in Park City, Utah. (Photo by Mike Ehrmann/Getty Images)

Xie Guobiao (C), 11, tied to a pillar with a rope, cries as his grandmother (L) and younger sister look on at his home in Daohui village of Lishui, Zhejiang province May 7, 2014. Xie was diagnosed as mentally handicapped when he was young, but the family was not able to provide him with sufficient medical treatment because of poverty. At the age of six, Xie started to sneak out of his home when others were not looking, climbing on top of houses and smashing windows. Xie's family had to pay over 10,000 yuan ($1,606) in compensation to others for the damage he caused. Since then, the family has had to tie Xie up with a rope both at home and in public, they said. (Photo by William Hong/Reuters)

Juno, a Beluga whale, greets a young viewer at the Mystic aquarium in Connecticut, USA on December 5, 2015. (Photo by Tim Clayton/Corbis)

A physically challenged girl looks at her brother as she is kept in a basin to seek alms from people on the street in Kano, Nigeria December 30, 2015. The girl has suffered from her condition since birth. (Photo by Reuters/Stringer)

Japanese artist Mami Kiyoshi has spent 15 years creating vivid portraits of people surrounded by their belongings – from wine bottles and violins to the odd stray pet. Mami Kiyoshi’s ongoing series “New Reading Portraits” is, in part, a nod to the mise-en-scène found in traditional woodcut printing. Here: Sakura and Kazuhiro, Tokyo, 2015. (Photo by Mami Kiyoshi/Galerie Annie Gabrielli/The Guardian)

Participants wearing fantasy costumes attend the 4th Hero Festival in Marseille, France on November 11, 2017. The 4th Hero Festival edition has attracted all sorts of people to role play their favourite characters from all kinds of movies and comic book legends. (Photo by Jean-Paul Pelissier/Reuters)

South Asian countries in terms of total contribution of travel and tourism to GDP. #6. Vietnam, Total GDP: USD 202.6 billion (2016). Contribution of Travel and Tourism to GDP: 9.1% . Here: A boat in the Thu Bon River, Hoi An, Vietnam. (Photo by Domingo Leiva/Getty Images)

Journalists interview a girl, member of the Cryophile amateurs winter swimmers club, after bathing in the ice waters of the Yenisei River, during the celebrations for the upcoming Christmas and New Year, in Krasnoyarsk, Russia, December 23, 2017. (Photo by Ilya Naymushin/Reuters)