Pigeon fancier Yonisbel Santana poses for a photo at his rooftop in Havana, Cuba, May 18, 2021. Havana's pigeon keepers crane out of a window, intently watching the grey birds take flight. Mostly staying indoors due to the country's worst outbreak of COVID-19 since the coronavirus pandemic began in March last year, Cubans are increasingly breeding pigeons as a form of escape. (Photo by Alexandre Meneghini/Reuters)

Young women wearing facemasks and traditional costumes of Song dynasty and Tang dynasty are seated on a bench in a park next to the East Lake in Wuhan, in China’s central Hubei province on May 17, 2020. The Guardian picture desk has chosen on December 17, 2020, the AFP photojournalist Hector Retamal as “Agency Photographer of the Year 2020” for his coverage of the novel coronavirus Covid-19 pandemic in Wuhan, China. (Photo by Hector Retamal/AFP Photo)

A five meters high sculpture “Pentateuque” created by Contemporary French artist Fabien Merelle, is displayed in Central, business district of Hong Kong, Tuesday, May 21, 2013. The artwork brings to real life the fantastical and seemingly impossible act of an average man balancing a gigantic elephant. The elephant and the man are modeled on one at the Singapore Zoo and on the artist himself. (Photo by Kin Cheung/AP Photo)

A photograph released to Reuters on August 22, 2014 shows the remains of an ancient Mayan city in Lagunita May 30, 2014. Archaeologists have found two ancient Mayan cities hidden in the jungle of southeastern Mexico, and lead researcher Ivan Sprajc, an associate professor at the Research Center of the Slovenian Academy of Sciences and Arts, says he believes there are “dozens” more to be found in the region. (Photo by Reuters/Research Center of the Slovenian Academy of Sciences and Arts)

Ukraine's Leonid Stadnyk, who stands at a height of 2.53 metres (eight feet four inches) and may be considered the world's tallest living man, near his house in the village of Podolyantsi in Ukraine's Zhytomyr region, about 200 km (124 miles) from the capital Kiev, 2005. (Photo by Reuters/Stringer)

In this Thursday, May 8, 2014 photo, Iranian coal miners push metal carts to be loaded with coal at a mine near the city of Zirab 212 kilometers (132 miles) northeast of the capital Tehran, on a mountain in Mazandaran province, Iran. International sanctions linked to the decade-long dispute over Iran's nuclear program have hindered the import of heavy machinery and modern technology in all sectors, and coal mining is no exception. (Photo by Ebrahim Noroozi/AP Photo)

A model of a ghost made from translucent fibreglass is lit from inside at Gem's (Wax Models) Ltd, in the Portobello Road area of west London. The ghost is due to go to the Capistrano Mission Museum in California, where tourists are told the legend of how he frightened a young Indian girl novice to death. 1st May 1965. (Photo by Chris Ware/Keystone Features)

A visitor stands in the exhibition “I Am A Drop In The Ocean” dedicated to the artistic and visual expressions of the protests that shook the Ukraine from November 2013 until February 2014 at the Kuenstlerhaus gallery in Vienna, Austria, Thursday, April 10, 2014. The exhibition opens its doors from April 11 until May 23, 2014. (Photo by Ronald Zak/AP Photo)