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)

A worker paints the Amazon Tall Tower Observatory (ATTO) in Sao Sebastiao do Uatuma in the middle of the Amazon forest in Amazonas state January 10, 2015. The Amazon Tall Tower Observatory is a project of Brazil's National Institute of Amazonian Research and Germany's Max Planck Institute and will be equipped with high-tech instruments and an observatory to monitor relationships between the jungle and the atmosphere from next July. According to the institutes, ATTO will gather data on heat, water, carbon gas, winds, cloud formation and weather patterns. (Photo by Bruno Kelly/Reuters)

A young girl plays on the glass bottom platform of the Oriental Pear TV Tower as she travels with her family on the second day of the Chinese Lunar New Year holiday, also known as Spring Festival, in Shanghai, China on February 18, 2018. Some 287 million tourists travelled in China during the first four days of the week-long Chinese Lunar New Year holiday, up 11.1 percent from the same period last year, new data showed Sunday. (Photo by Imaginechina/Rex Features/Shutterstock)

Grey seal pup “Nikolaus” licks a window at the seal enclosure in Friedrichskoog, Germany, 19 December 2014. The pup was abandoned by his mother and would not have a chance at survival without human help. Nikolaus will be fed at the enclosure for two to three months until he has reached the minimum weight of 45 kilograms for being released. (Photo by Daniel Reinhardt/EPA)

In this photo taken in October 1917, provided by Russian State Documentary Film and Photo Archive, a machine gunner looks through a window at his position near the Kremlin in Moscow, Russia. The 1917 Bolshevik Revolution was long before the digital revolution allowed anyone to instantly document events. But the clumsy cameras of the time still caught some images that capture the period's drama. (Photo by Russian State Documentary Film and Photo Archive via AP Photo)

Respect, Kronotsky nature reserve, Russia. The photographer’s cat, Ryska – her name means little lynx in Russian – stands outside their cabin and with aggressive posturing warns off a fox. In winter, foxes would regularly visit the cabin searching for food. If one peered in at the window, possible when the snow was deep, Ryska would sit on the other side, fur raised, and growl. When outside, she would hold her ground. The foxes were not always frightened and so encounters could be a sort of dance. (Photo by Igor Shpilenok/Unforgettable Behaviour/NHM)

Hooded demonstrators vandalise a shop window in Mexico City, during the commemoration of the 50th anniversary of the 1968 Tlatelolco student massacre, on October 2, 2018. Fifty years ago, Mexican troops opened fire on student demonstrators, killing hundreds just days before Mexico City hosted the 1968 Olympics – one of the darkest episodes in a year of global turbulence. (Photo by Ronaldo Schemidt/AFP Photo)