Masked Guggen music bands parade through the streets on the occasion of the beginning of the Fasnacht Carnival of Lucerne, Switzerland, early 23 February 2017. (Photo by Urs Flueeler/EPA)

A woman walks behind the installation “Wandering boy is forever attractive” (1985) by Tetsumi Kudo during the press preview at the exhibition “Tetsumi Kudo – Retrospective” in the Fridericianum in Kassel, Germany, Friday, September 23, 2016. The exhibition offers an in-depth, comprehensive view of works by the Japanese artist Kudo. It starts on Sept. 25, 2016 and lasts until Jan. 1, 2017. (Photo by Jens Meyer/AP Photo)

Revellers take part in the traditional “Weiberfastnacht” (Women's Carnival) celebration in Mainz, Germany, February 4, 2016. Germany is celebrating its traditional carnival with tight security after assaults on women during New Year's Eve celebrations across the country. (Photo by Kai Pfaffenbach/Reuters)

Alex Plunkett, left, and Sean Hart, both of Arlington, Va., join hundreds participating in the annual International Pillow Fight Day on April 5. Massive pillow fights broke out on the Mall in Washington and in cities around the world. (Photo by Marvin Joseph/The Washington Post)

A view of trees shrouded in fog on a late summer morning between Tureby and Slimminge on Zealand, Denmark, 10 September 2021. (Photo by Mads Claus Rasmussen/EPA/EFE)

Anti-pollution protesters wearing traditional costumes and contemporary gas masks ride bicycles in the Qingming Grand river park in Kaifeng, Henan Province, China on January 1, 2017. The Beijing Municipal Environmental Protection Bureau extended an “orange alert” for heavy air pollution for three more days. (Photo by SIPA Asia/Rex Features/Shutterstock)

A tale of two foxes. Surprising behaviour, witnessed in Wapusk national park, on Hudson Bay, Canada, in early winter. Red foxes don’t actively hunt Arctic foxes, but where the ranges of two predators overlap, there can be conflict. Though the light was poor, the snow-covered tundra provided the backdrop for the moment that the red fox paused with the smaller fox in its mouth in a grim pose. (Photo by Don Gutoski/2015 Wildlife Photographer of the Year)

Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)