Egyptian bootblacks cleaning a European's shoes in Cairo. (Photo by Hulton Archive/Getty Images). Circa 1870

BASE jumper Luke Denniss of Australia gestures as he dives in the air from the Kuala Lumpur Tower during the KL Tower International Jump in Kuala Lumpur, Malaysia, Saturday, September 27, 2014. BASE stands for the places such jumpers usually jump from: buildings, antennas, spans (bridges) and earth (cliffs). (Photo by Lai Seng Sin/AP Photo)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

A man is publicly flogged by a member of the Sharia police after he was found guilty of raping a child, in Idi Rayeuk, East Aceh on November 26, 2020. (Photo by Cekmad/AFP Photo)

The Taal Volcano in the central Philippines boomed to life on Sunday, January 12, 2020 spilling ash and causing evacuations in nearby communities – and officials warn that a more powerful eruption is imminent. One of the world’s smallest volcanoes, Taal is among two dozen active volcanoes in the Philippines, which lies along the so-called Pacific Ring of Fire, a seismically active region that is prone to earthquakes and volcanic eruptions. (Photo by Kester Ragaza/Pacific Press/Rex Features/Shutterstock)

A dancer attends the final rehearsal for the new “VIVID Grand Show” at Friedrichstadt-Palast in Berlin, Germany, September 26, 2018. (Photo by Hannibal Hanschke/Reuters)

An Atlantic seal pup lies amongst the rocks at St Martin's Haven, Pembrokeshire, Wales, Britain October 8, 2018. Seal pups are born with fluffy white non-waterproof coats which they moult out in their fourth week. (Photo by Rebecca Naden/Reuters)

A youth skates next to a road in Palembang, South Sumatra, Indonesia on August 15, 2018. (Photo by Edgar Su/Reuters)