Framed by the setting sun, an American Bison grazes at the Tallgrass Prairie National Preserve on Tuesday, April 28, 2015, near Strong City, Kan. The buffalo herd at Tallgrass is one of the few herds of wild bison left in the United States. (Photo by Travis Heying/The Wichita Eagle via AP Photo)

An aircraft crosses a bridge over a highway the airport in Frankfurt, Germany, Friday, September 20, 2019. Protests of the “Friday For Futurte” movement against the increase of carbon dioxide emissions are planned Friday in cities around the globe. In the United States more than 800 events were planned Friday, while in Germany more than 400 rallies are expected. (Photo by Michael Probst/AP Photo)

A man carries away an injured girl while walking through debris past in the Achrafiyeh district in the centre of Lebanon's capital Beirut on August 4, 2020, following an explosion at the nearby port of Beirut. (Photo by The Mega Agency/Stringer)

Listed as endangered on the IUCN red list of threatened species, a humphead wrasse, or Napoleon fish, swims in an aquarium during an event in Tokyo's shopping district of Ginza on August 5, 2019. (Photo by Kazuhiro Nogi/AFP Photo)

A morning fog is seen in the Siberian city of Omsk, Russia on October 8, 2019. (Photo by Alexey Malgavko/Reuters)

This photo shows sunset in Eagle, Colo., Sunday, November 3, 2019. Daylight saving time ended, making sunset around 5 p.m. this time of year in Colorado. (Photo by Chris Dillmann/Vail Daily via AP Photo)

A British Spitfire and an American P-51 Mustang from Ultimate Warbird Flights take to the Northamptonshire on August 14, 2020 skies to mark the 75th anniversary of VJ Day. (Photo by Richard Pohle/The Times)

An orphaned giraffe nuzzling a wildlife keeper at Sarara camp in Kenya, one of 70 pictures being sold by Prints for Nature (printsfornature.com) to raise money for work by the Conservation International charity. This giraffe was rehabilitated and returned to the wild, as a number of others have done before him. Right now, giraffe are undergoing what has been referred to as a silent extinction. Current estimates are that giraffe populations across Africa have dropped 40 percent in three decades, plummeting from approximately 155,000 in the late 1980s to under 100,000 today. (Photo by Ami Vitale/National Geographic)