The brilliant iridescent hues found in ammolite come from tiny air gaps in the fossils’ layers, a new study finds. By Alexa Robles-Gil Millions of years ago, squid-like creatures called ammonites swam ...

You’re in good company if you’ve combed the shoreline for shells, marveled at the glinting, microscopic pieces that make up the sand, or held a snail shell up to your ear listening for the ocean or ...