Earth Day: Top Nature Photos of All Time

Forty iconic nature photographs will go to auction this week in honor of the 40th annual Earth Day on April 22. This one, "Twilight of the Giants," was taken by Frans Lanting in Botswana's Chobe National Park in 1986. Selected by the International League of Conservation Photographers (ILCP), the "40 Greatest Nature Photographs of All Time" include spectacular images of animals, plants and natural landscapes. The full gallery of photos is available HERE but you can click through our slideshow to see 10 of them. (Frans Lanting Photography, via International League of Conservation Photographers)