Cave Featuring Native American Wall Art Is Sold to Anonymous Bidder

The cave, which sold for $2.2 million in St. Louis on Tuesday, is considered a sacred site by members of the Osage Nation. A tribal leader called the sale “heartbreaking.”

A Stunning Look at the Hidden Mysteries of Glacier Caves

A group of scientists and adventure athletes are venturing into icy labyrinths to study their relationships with glacial melting and climate change.

Is It Art? You May Have to Ask a Neanderthal Critic.

A bone to pick from Germany’s Unicorn Cave. Plus fireflies in sync, peer review in crisis and China’s astronauts at work in their spacesuits.

Why Did the Cave Art Vanish? It Was Erased by This Furry Creature and Its Feces.

Bats roosting in caves produce ample guano, which may explain why prehistoric marks left by humans cannot be found in some places where they are expected.