Nursery plants are seen placed in people's seats during a rehearsal as Barcelona's Gran Teatre del Liceu opera reopens its doors with a concert for plants, to raise awareness about the importance of an audience after the coronavirus lockdown, in Barcelona, Spain on June 22, 2020. The Gran Teatre del Liceu reopens its doors, in which the 2,292 seats of the auditorium will be occupied on this occasion by plants. It will be on 22 June, broadcast live online, when the UceLi Quartet string quartet performs Puccini's “Crisantemi” for this verdant public, brought in from local nurseries. (Photo by Nacho Doce/Reuters)

Supporters of Venezuela's President Nicolas Maduro take part in a rally in support of the government in Caracas, Venezuela on May 20, 2019. (Photo by Ivan Alvarado/Reuters)

Miners pulling up lazy tourists to the rim of Kawah Ijen (Ijen Volcano), East Java, Indonesia on September 21, 2017. They will earn as much as they would bring down a load of sulfur. Nomadic Explorer, Cultural Lifestyle Photographer Claudio Sieber captured striking images of miners working at Ijen volcanic range in East Java, Indonesia. The sulphur miners risk their lives daily as they climb the active volcano carrying heavy loads, which they sell to sugar refineries. (Photo by Claudio Sieber/Barcroft Images)

Long-tailed mayflies (Palingenia longicauda) at Tisza river near Tiszainoka 135km (84 miles) southeast of Budapest, June 23, 2013. Millions of these short-lived mayflies engage in a frantic rush to mate and reproduce before they perish in just a few hours during “Tiszaviragzas” or Tisza blooming season from late spring to early summer every year. (Photo by Laszlo Balogh/Reuters)

In this October 16, 2014 photo, a man cleans his American classic car before going to work in Havana, Cuba. While the U.S. embargo that took effect in 1961 stopped the flow of new cars, and most parts, a few Cubans now manage to bring in replacement parts when friends or family visit from the U.S. (Photo by Franklin Reyes/AP Photo)

A Cambodian girl goes through the garbage dump looking for things to recycle in order to survive July 26, 2003 in Phnom Penh, Cambodia. Rampant corruption in this impoverished country has lead to extreme poverty with many Cambodians living below the poverty line. (Photo by Paula Bronstein/Getty Images)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)

A three-seater Toyota Kikai concept car is displayed during the 2016 CES trade show in Las Vegas, Nevada January 8, 2016. (Photo by Steve Marcus/Reuters)