In the real world, striving for the ideal may not be worth it. It would seem axiomatic that well-designed animals outperform badly designed ones and pass on to their offspring the genes that helped create that design. As good genes arise and spread, animal designs should theoretically shift from the flawed toward the better. So when a design is significantly inferior to what might seem best for a given situation, something interesting is probably going on.
Limpets are marine gastropods that live on rocky coasts and in tide pools.
The limpet's shell, a low cone that looks like a gently sloping hill, provides protection from crabs, birds, and other predators. It also helps the animals survive the waves that regularly slam against them at speeds greater than eighty feet per second. The shape of a limpet's shell has a great deal to do with whether the animal remains securely attached to its rock or is ripped off and thrown onto dry land or into the waiting tentacles of a hungry sea anemone. There are two ways a wave can dislodge a limpet. If the limpet's shell is steep-sided, the drag of the water against the sides of the shell will force it in the direction of the wave.