Gelada baboons (Theropithecus gelada) play in their enclosure at the Zoo in Zurich, Switzerland, Wednesday, May 15, 2013. (Photo by Steffen Schmidt/Keystone/AP Photo)

Revelers throw a woman to the air during the opening and the firing of the “Chupinazo” rocket which starts the 2014 Festival of the San Fermin Running of the Bulls on July 6, 2014 in Pamplona, Spain. The annual Fiesta de San Fermin, made famous by the 1926 novel of US writer Ernest Hemmingway entitled “The Sun Also Rises”, involves the daily running of the bulls through the historic heart of Pamplona to the bull ring. (Photo by Pablo Blazquez Dominguez/Getty Images)

Shepherds from the north wear their traditional heavy woollen mantles as they stand ready to shear sheep with sycthe-like shears. (Photo by Three Lions/Getty Images). Circa 1952

A sun bear is offered chocolate by a visitor in its enclosure at a zoo in Bandung on January 18, 2017. Animal rights activists on January 18 demanded the closure of an Indonesian zoo after skeletal sun bears were pictured begging for food from visitors and eating their own dung. (Photo by Timur Matahari/AFP Photo)

A competitor shouts as he takes part in the “Tough Guy” adventure race near Wolverhampton, central England, on January 29, 2017. The Tough Guy event, which is being held for the final time in its 30th year, challenges thousands of competitors to run a gruelling course whilst negotiating over 200 obstacles including: water, fire, and tunnels. (Photo by Oli Scarff/AFP Photo)

A woman already appears to be regretting her choice of heels for the day out during the Grand National Festival at Aintree Racecourse on April 8, 2017 in Liverpool, England. (Photo by Alamy Stock Photos)

A student from “the cliff village” in Atule'er climbs newly-constructed steel ladders after school to go home for holidays, in Liangshan Sichuan province, China, November 19, 2016. The steel ladders which replaced the unsafe vine ladders shortened the time taken for the children to go home, from three hours to two. (Photo by Reuters/Stringer)

Steamed Chinese-style buns, known locally as salapao, are decorated with faces during the start of the annual 10-day vegetarian festival in Bang Saphan, southern Thailand on October 13, 2015. (Photo by Matthew Richards/Courtesy Image)