The sun beats down on my shoulders as I stroll casually down the waterline. Small, fragile, shells crunch beneath my feet, and grains of sand work themselves between my toes. I can hear birds calling, and children shouting and laughing. I pause to bend over and pick up a shell. All along the beach, shells are piled along the wrack line. Sanibel Island is one of my favorite places in the world, and the shells are part of the reason.