Photo of the Day

Picture of park guides working in a cave in Australia
October 9, 2021

Cave Explorations

In Kelly Hill Caves on Australia's Kangaroo Island, park guides search for bones of ancient megafauna that once populated the country. The sudden extinction of such giant animals, believed to have happened soon after the arrival of humans about 13,000 years ago, has baffled scientists for decades.
Photograph by Amy Toensing, Nat Geo Image Collection

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