Children playing on Walled City rooftop in Hong Kong, 1989. The lack of formal governance in the Walled City led to challenges, but it also fostered a unique system of informal social order. (Photo by Greg Girard/The Guardian)

A Burmese worker sets up Christmas lights inside a woman's clothing store inside a shopping mall December 6, 2011 in Nay Pyi Taw, Myanmar. (Photo by Paula Bronstein/Getty Images)

Freya Smith aged three, leads one of Erth’s giant dinosaur puppets across the road on August 6, 2019 in Edinburgh, Scotland. Australian theatre company Erth presents their best-selling show Dinosaur’s Zoo as part of Underbelly’s Fringe programme. Featuring giant dinosaur puppets which walk, roar and blink like the real thing, Dinosaur’s Zoo is a perfect example of edutainment for children of all ages, taking place at the McEwan Hall every day of the Fringe at 11am. (Photo by Jeff J. Mitchell/Getty Images)

Cambodian children sleep on a pavement at a park in Phnom Penh on July 8, 2016. (Photo by Tang Chhin Sothy/AFP Photo)

A tiger cub has a short chat with a chimp. (Photo by Ian Tyas/Keystone Features/Getty Images). 27th November 1979

A visitor holds up her toy bunny to the aquarium glass in front of Aurora the Russian polar bear at the Sao Paulo Aquarium in Sao Paulo, Brazil, Thursday, April 16, 2015. (Photo by Andre Penner/AP Photo)

Wadha al-Sayyed, wife of captive Lebanese soldier Khaled Moqbel, protests for his release and government action, near burning tyres blocking a road in Beirut, December 15, 2014. More than two dozen members of the Lebanese security forces are being held by Sunni Islamists. (Photo by Hasan Shaaban/Reuters)

Russian soldiers rehearse ahead of a forthcoming parade on Red Square in Moscow on November 5, 2017 The event will take place on November 7, marking the 76 th anniversary of a 1941 parade, when Red Army soldiers marched past the Kremlin walls towards the front line to fight Nazi Germany troops during World War Two. (Photo by Mladen Antonov/AFP Photo)