A man is silhouetted in front of the Allianz-Arena as he walks his dogs at sunrise in Munich, southern Germany, Friday, April 10, 2015. (Photo by Peter Kneffel/AP Photo/DPA)

A visitor holds up her toy bunny to the aquarium glass in front of Aurora the Russian polar bear at the Sao Paulo Aquarium in Sao Paulo, Brazil, Thursday, April 16, 2015. (Photo by Andre Penner/AP Photo)

A mass pillow fight in Trafalgar Square in central London on April 5, 2014 on International Pillow Fight Day. (Photo by Jane Scanlan)

Bollywood actress Chitrashi Rawat lies in a plastic drum as she is briefed by a crew member during the shoot for the film “Black Home” at a beach on the outskirts of Mumbai April 26, 2013. (Photo by Danish Siddiqui/Reuters)

Show promoters for Motolite batteries sit on a jeepney as they pose for photographers during the Manila International Auto show in Pasay, Metro Manila, Philippines on April 4, 2013. (Photo by Erik De Castro/Reuters)

A pale tussock moth (Calliteara pudibunda) larva or caterpillar just after moulting on heather on Hankley Common, Surrey, England on April 30, 2019. (Photo by Gillian Pullinger/Alamy Stock Photo)

Sunrise in Ely, Cambridgeshire on April 15, 2020 by the River Great Ouse, England. The warm weather is set to continue until the weekend. (Photo by Veronica Johansson Poultney/Bav Media)

A municipality worker in a protective suit feeds street cats at Sultanahmet Square, as the spread of coronavirus disease (COVID-19) continues in Istanbul, Turkey, April 9, 2020. (Photo by Umit Bektas/Reuters)