Poppy, a female Crowned sifaka, inspects a photographer's camera in the enclosure at the zoo of Mulhouse, eastern France, on March 5, 2019. The Crowned sifaka is a critically endangered species from Madagascar. (Photo by Sebastien Bozon/AFP Photo)

Police officers detain an opposition protester during a May Day rally in Saint Petersburg, Russia on May 1, 2019. Labor Day or May Day is observed all over the world on the first day of the month of May to celebrate the economic and social achievements of workers and fight for laborers rights. (Photo by Igor Russak/Reuters)

Nice's Youcef Atal, left, and PSG's Juan Bernat challenge for the ball during the French League One soccer match between Paris Saint-Germain and Nice at the Parc des Princes stadium in Paris, France, Saturday, May 4, 2019. (Photo by Christophe Ena/AP Photo)

A cosplayer poses during Day 2 of London MCM Comic Con 2019 at ExCel on May 25, 2019 in London, England. (Photo by Jack Dredd/Rex Features/Shutterstock)

Participants play in the mud as they plant rice samplings during National Paddy Day, also called Asar Pandra, that marks the commencement of rice crop planting in paddy fields as monsoon season arrives, in Dhading, Nepal, June 30, 2019. (Photo by Navesh Chitrakar/Reuters)

6th Place: Javier Rupérez, Almáchar, Málaga, Spain. Small white hair spider. Reflected Light, Image Stacking, 20x (Objective Lens Magnification). (Photo by Javier Rupérez/Nikon's Small World 2019)

To the woman presented a flower in Sevastopol, Ukraine, on March 8, 2013. Activists presented this day on the street free 155 tulips to women. The police tried to arrest activists for illegal trade as couldn't believe in free distribution of flowers. (Photo by Sergey Anashkevitch)

A pro-democracy demonstrator fights with a Soviet soldier on top of a tank parked in front of the Russian Federation building on August 19, 1991, after a coup toppled Soviet President Mikhail Gorbachev. The same day, thousands in Moscow, Leningrad, and other cities answered Russian Republic President Boris Yeltsin's call to raise barricades against tanks and troops. (Dima Tanin/AFP/Getty Images)