Digging for Dollars
SEABIRDS CRY IN the salty air as you stroll along the shore, seeking shells. What’s that? You stoop down to have a closer look, shading your eyes from the sun. Right under the surface of the water is a small round disk with a flower pattern in the middle—a sand dollar!
If you’ve ever been lucky enough to find one of these beauties on a shell hunt, what you’ve picked up is not the sand dollar itself, but its “test,” or skeleton.
Why is it so hard
