(Inside Science) -- Castles made of sand could, with the help of bacteria, grow copies of themselves and become as strong as the cement that commonly holds bricks together, a new study suggests.
Such living materials could one day help people colonize Mars, scientists added.
After water, concrete is the most used material on Earth, at a rate of about 3 metric tons used per year for every person in the world. Cement, the primary component of concrete, is the oldest artificial construction material, dating back to the Roman Empire.
