Predator induced defenses in Daphnia longicephala (top row, credit: Linda Weiss) and Daphnia pulex (bottom row, credit: Sina Becker). Left shows an undefended morphotype, right shows the defended morphotype. Insert shows magnification of expressed neckteeth. These morphological features render Daphnia less susceptible to predators. When the expression of these defensive traits is hampered by high levels of pCO2, Daphnia is suspected to fall as prey more easily.