Students from St Andrews University are covered in foam as they take part in the traditional Raisin Weekend in the Lower College Lawn, at St Andrews in Scotland on October 22, 2018. The “raisin weekend” stems from a gift of raisins (now flour and foam) traditionally given by a first year student to their academic “parents” in gratitude for their guidance. (Photo by Russell Cheyne/Reuters)

A South Korean marine in action during their regular drill on Yeonpyeong Island, South Korea November 1, 2018. (Photo by Jeon Heon-Kyun/Pool via Reuters)

Sukhoi Su-30SM jet fighters of the Russkiye Vityazi (Russian Knights) aerobatic team perform during a demonstration flight in Krasnoyarsk, Russia October 6, 2018. (Photo by Ilya Naymushin/Reuters)

The Swiss Air Force Patrouille Suisse aerobatic team performs during the men's downhill race at the Alpine Skiing FIS Ski World Cup in Wengen, Switzerland, Saturday, January 19, 2019. (Photo by Anthony Anex/Keystone via AP Photo)

This photo taken on April 4, 2021 shows migratory birds flying over a wetland near the Yalu River in Dandong, in China's northeastern Liaoning province. (Photo by AFP Photo/China Stringer Network)

An injured demonstrator hugs another as riot police officers prevent them from attending a Pride parade, which was banned by local authorities, in central in Ankara, Turkey on June 29, 2021. (Photo by Cagla Gurdogan/Reuters)

A man rides a skateboard at Radical Park in Rio de Janeiro, Brazil, Thursday, June 24, 2021. Hundreds of joggers, dog walkers, skateboarders and picnicking families come each day. (Photo by Bruna Prado/AP Photo)

A Bengal tigress who gave birth to four cubs at the Guadalajara Zoo, Jalisco state, Mexico runs at the zoo on October 5, 2021. (Photo by Ulises Ruiz/AFP Photo)