Dhruva Aliman does a back somersault as he dismounts from a slackline on the beach at Santa Monica, California on October 19, 2014. Slackline is a balance sport where a line of webbing is adjusted at different levels of tension between two anchor points and participants (called slackers) perform tricks and stunts including somersaults. (Photo by Mark Ralston/AFP Photo)

Russia's Maria Stavitskaia performs during the ladies short program at the Rostelecom Cup ISU Grand Prix of Figure Skating in Moscow November 14, 2014. (Photo by Grigory Dukor/Reuters)

Shoppers wrestle over a television as they compete to purchase retail items on “Black Friday” at an Asda superstore in Wembley, north London November 28, 2014. Britain's high streets, malls and online sites were awash with discounts on Friday as more retailers than ever embraced U.S.-style “Black Friday” promotions, seeking to kickstart trading in the key Christmas period. In the United States the Friday following the Thanksgiving Day holiday is called Black Friday because spending usually surges and indicates the point at which American retailers begin to turn a profit for the year, or go “into the black”. (Photo by Luke MacGregor/Reuters)

People take pictures with their mobile phone of a scale model of a dinosaur displayed in front of La Sapienza University headquarters in Rome April 10, 2015. The realistic reproductions of dinosaurs are part of the “Dinosaurs in the flesh, science and art bring to life the rulers of a lost world” exhibition. (Photo by Alessandro Bianchi/Reuters)

Ciara attends the 2018 Vanity Fair Oscar Party following the 90th Academy Awards at The Wallis Annenberg Center for the Performing Arts in Beverly Hills, California, on March 4, 2018. (Photo by Jean-Baptiste Lacroix/AFP Photo)

Members of the Delirio dance company perform during the “Hechizo” (Spell) virtual show, inspired by the legend of the merry widow on Hallo​ween night, in Cali, Colombia, 31 October 2020. (Photo by Ernesto Guzman Jr./EPA/EFE)

Ellen MacRae a student from Edinburgh University take a lateral flow antigen test at a test centre which is also open to students in Edinburgh Napier University, Queen Margaret University and SRUC on December 1, 2020 in Edinburgh, Scotland. The programme is running in partnership between the University of Edinburgh and other Scottish universities, the Scottish Government and NHS Test and Protect, supporting students leaving their term-time accommodation to travel home at the end of term for the winter break. (Photo by Jeff J. Mitchell/Getty Images)

Medical workers wearing gear enter a residential area placed under the enhanced movement control order (EMCO) due to a drastic increase in the number of COVID-19 cases recorded in Sunway, outskirt of Kuala Lumpur, Malaysia, Friday, July 2, 2021. Malaysia starts to further tighten movement curbs and impose a curfew in most areas in its richest state Selangor and parts of Kuala Lumpur, where coronavirus cases remain high despite a national lockdown last month. (Photo by Vincent Thian/AP Photo)