Students attend a stewardess skill training for the upcoming 2017 entrance examination for art majors in colleges in Luoyang, central China's Henan Province, January 4, 2017. Along with how to stand, how to sit is also covered in these classes. (Photo by Li Bo/Xinhua/Barcroft Images)

Members of the Communist New Fourth Army on parade. Note how the modern equipment contrasts with the shoeless soldiers in the foreground. (Photo by Hulton Archive/Getty Images). 6th July 1946

Meet the star students of orangutan school – the unique rehab centre where orphaned apes are taught how to climb trees and survive in the wild without their mum and dad. (Photo by Caters News)

Bullet the bulldog skateboards in a seafront area in the city of Vladivostok, on Russia's Pacific coast on August 9, 2021. The 6-year-old dog learnt how to skateboard two years ago thanks to his owner, Sergei Shukshuyev. (Photo by Yuri Smityuk/TASS)

Joel said documenting the Kazakh nomad summer migration was really an epic journey – a time travel journey – and at the same time was possible to get an understanding of how the balance of nature is still possible in Altai Mountains, Mongolia, June 2015. (Photo by Joel Santos/Barcroft Images)

It is already one of the world’s most iconic cities, but this incredible collection shows how much Paris has changed over the course of the past century. The collection, by French photographer Julien Knez, shows Paris in the 1940s against a backdrop of how the same places look today. Knez says he put the striking collection together to celebrate the 71st anniversary of the city’s liberation from Nazi control in August 1944. Here: Soldiers outside the Hotel De Ville in the 1940s. (Photo by Julien Knez/Caters News)

In this January 12, 2015 photo, a wall of collectable sneakers are displayed at Sneaker Pawn in the Harlem section of New York. Basketball sneakers can re-sell for hundreds of dollars, depending on the model, the size of the production run and how easy it is to find a pair in good condition. (Photo by Seth Wenig/AP Photo)