Walk the beach or peer into a tidepool anywhere along the northeastern US coast, and you'll find shells stacked on top of one another. They're most likely common Atlantic slipper shells, a species of marine snail.
Fuente : http://www.eurekalert.org/pub_releases/2013-12/nsf...
Fuente : http://www.eurekalert.org/pub_releases/2013-12/nsf...