Tourists sit around a bonfire on the Makgadikgadi salt pan in Botswana. (Photo by Yang Mengxi/Xinhua News Agency/Barcroft Media)

This photo provided by Netflix/naturepl.com and WWF-International shows an African Elephant (Loxodonta africana) in front of double rainbow, in Masai Mara, Kenya, included in the Netflix natural history series, “Our Planet”, in collaboration with Silverback Films and WWF. The eight-part series debuts in 2019. (Photo by Andy Rouse/Naturepl/WWF-International/Netflix via AP Photo)

A young boy scavenges for re-sellable items from garbage on the streets, runs past a sign showing incumbent President Muhammadu Buhari, left, and local party official Mustapha Dankadai, right, in Kano, northern Nigeria Friday, February 15, 2019. (Photo by Ben Curtis/AP Photo)

A grasshopper rests on a photographic camera during a meeting in the village of Alto Jamari called to face the threat of armed land grabbers invading the Uru-eu-wau-wau Indigenous Reservation near Campo Novo de Rondonia, Brazil on January 30, 2019. (Photo by Ueslei Marcelino/Reuters)

Manchester City's Phil Foden celebrates after scoring his side's sixth goal during the Champions League round of 16 second leg, soccer match between Manchester City and Schalke 04 at Etihad stadium in Manchester, England, Tuesday, March 12, 2019. (Photo by Dave Thompson/AP Photo)

In this Sunday, March 24, 2019, file photo, free skate pairs gold medalist Sui Wenjing and Han Cong of China perform during the gala exhibition for the ISU World Figure Skating Championships at Saitama Super Arena in Saitama, north of Tokyo. (Photo by Annice Lyn/AP Photo)

Hannah Rice, 18, jumps from a stump after posing for a photograph next to a large bust of President Franklin D. Roosevelt while touring busts of U.S. presidents in Williamsburg, Va. on March 30, 2019. The statues were once part of an attraction called Presidents Park, which has since closed. (Photo by Matt McClain/The Washington Post)

In this Tuesday, April 16, 2019, file photo, a visitor posing for a photo walks though azalea blossoms at Nezu Shrine during a day of mild spring weather in Tokyo. Nezu Shrine is one of the oldest shrines in Tokyo. (Photo by Eugene Hoshiko/AP Photo/File)