The performers prepare for the show. Fontana, a travelling water circus produced by Cirque Du Liban at Festival City in Dubai. (Photo by Chris Whiteoak/The National)

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)

This aerial picture taken on the night of November 12, 2018 shows traffic on an elevated intersection in downtown Shanghai, China. (Photo by Johannes Eisele/AFP Photo)

This aerial photo taken on December 28, 2018 shows commercial and residential buildings in Hong Kong. (Photo by Dale De La Rey/AFP Photo)

Gray whale feeding at the surface and showing it's baleen. (Photo by Christopher Swann/Biosphoto)

Models pose backstage at the Celia Kritharioti Spring/Summer 2012 fashion show at One Mayfair on March 20, 2012 in London, England. (Photo by Ian Gavan/Getty Images For Celia Kritharioti)

A model walks down the runway during the Odd Molly Autumn/Winter 2012 Fashion Show at Berns on February 1, 2012 in Stockholm, Sweden. (Photo by Ian Gavan/Getty Images)

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