A hippopotamus performs during a show at the circus in Krasnoyarsk, Siberia, Russia, July 7, 2016. (Photo by Ilya Naymushin/Reuters)

Baby giraffe of Niger (Giraffa Camelopardalis) “Kenai” (R), born on August 25, 2016, kisses his mother “Dioni” on August 31, 2016 at the zoo of La Fleche, northwestern France. (Photo by Jean-Francois Monier/AFP Photo)

A keeper feeds a four-week-old jaguar while presenting it to the media, at a zoo in Ciudad Juarez, Mexico, October 14, 2015. (Photo by Jose Luis Gonzalez/Reuters)

A heat-stressed koala waits as a resident pours water on its back on December 19, 2015 in Adelaide, Australia. Adelaide is experiencing an extreme heatwave, with temperatures reaching over 40 degrees for five consecutive days. (Photo by Morne de Klerk/Getty Images)

British prime minister Winston Churchill (1874–1965) stops to pet a cat at Liverpool Street Station, 24th May 1952. (Photo by Keystone/Hulton Archive/Getty Images)

A great tit eats food from the top of a photographer's hat as the press wait for politicians on Downing Street on December 16, 2019 in London, England. The UK's Prime Minister is set to hold a mini Cabinet reshuffle to replace outgoing ministers following last week's general election victory. (Photo by Leon Neal/Getty Images)

Three white tigers cub born on January 05, 2020 stand beside their mother Orissa at the zoological park of Amneville, northeastern France, on March 9, 2020. (Photo by Jean-Christophe Verhaegen/AFP Photo)

A dog wearing a mask is seen on a street following an outbreak of the novel coronavirus disease (COVID-19), in Shanghai, China on March 22, 2020. (Photo by Aly Song/Reuters)