Dear David;- Now I'm not saying this to be funny. This is the other ME. In given circumstances, there is an advantage to being sinistral. I'm thinking of baseball. The advantage occurs because of its uniqueness. There are a higher percentage of left handed baseball players than in any other sport or human endeavor. I only offer this to indicate that we may have to widen our search to find advantage or dis-advantage among mollusks. Does anyone know if great apes and monkeys favor left or right hands? Art