Survival of the Fittest (IMAGE) University of Pittsburgh Caption The surface area of active sites on the red crab is twice that of the green grab; therefore, the red crab draws particles away from green competitors by generating stronger inward flows (marked with black arrows). Credit Abhrajit Laskar/Anna Balazs Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.