Sand dunes are formed over many years when beach grass and other plants trap windblown sand. As more and more sand becomes trapped, a dune expands to store more sand. Sand dunes serve as sand reserves for beaches and help protect inland areas from storm surges, floods, wind, and waves.
A dune<span> is a mound of </span>sand<span> formed by the wind, usually along the beach or in a desert. </span>Dunes form<span> when wind blows </span>sand<span> into a sheltered area behind an obstacle. </span>Dunes<span> grow as grains of </span>sand accumulate. Sand dunes<span> serve an important purpose by protecting inland areas from coastal water intrusion. They are able to absorb the impact and protect inland areas from high energy storms and act as a resilient barrier to the destructive forces of wind and waves.</span>
The Olmecs, aka the earliest known major civilization in Mexico following a progressive development in Soconusco. They lived in the tropical lowlands of south central Mexico
