An air tanker drops fire retardant on flames as firefighters continue to battle against the Detwiler fire in Mariposa, California on July 19, 2017. The Detwiler fire is currently at 7 percent containment and has burned more than 45,000 acres and destroyed eight structures. (Photo by Josh Edelson/AFP Photo)

Aerial view of a boat working in the green water of Taihu Lake covered by blue-green algae, Wuxi city, Jiangsu province, China on May 23, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)

A suspected Vietcong is kicked by a Vietnamese soldier holding a rifle as another soldier attempts to tie his hands on October 22, 1965. The prisoner was one of 15 captured October 21 near Xom Chua when government troops raided in the plain of reeds area. Troops killed 43 suspected Vietcong and seized some arms. (Photo by Richard Merron/AP Photo)

Chieftain Japarupi Waiapi shows a roasted monkey -part of Waiapi's diet, also based in Manioc and fruits- at the reserve in Amapa state in Brazil on October 13, 2017. When Waiapis walks into the Amazon forest surrounding their village, they do not see trees, but a kind of shopping mall providing medicine, food, shelter, tools and weapons all under the eye of multiple spirits. (Photo by Apu Gomes/AFP Photo)

A golden pheasant and squirrels are seen in Lushan County of Pingdingshan City, central China's Henan Province, November 14, 2017. (Photo by Liu Xianguo/Xinhua/Barcroft Images)

School leavers celebrate their graduation in Moscow's Red Square in Moscow, Russia on June 20, 2019. (Photo by Artyom Geodakyan/TASS)

A Dead Leaf butterfly (Kallima inachu formosana, also called Orange Oakleaf Butterfly) rests on a tree trunk at the Taipei Zoo in Taipei, Tawian, 03 August 2019. Dead Leaf butterfly can be found in Tropical Asia from India to Japan. When its wings close, it resembles a dead leaf, providing camouflage against predators including birds, ants, spiders and wasps. (Photo by David Chang/EPA/EFE)

An AI Gamer “Q56” robot plays a video game during a demonstration at the Bandai Namco Holdings Inc. booth at the Combined Exhibition of Advanced Technologies in Chiba, Japan on October 16, 2019. (Photo by Kiyoshi Ota/Bloomberg)