Male Secondary Sexual Traits and Fluid Dynamic Drag of the Japanese Filefish Paramonacanthus japonicus

摘要

Wind tunnel experiments are conducted to measure drag forces of wooden Japanese filefish models with and without their skin. The drag coefficient C{sub}D of male model is smaller than that of female model. This is so called form effect of male and female filefish. The drags of male and female models with their real skins have the same trends of their real specimen's results. C{sub}D of male with female skin is as same as that of the female specimen. The form and skin effects are concluded that the drag performance differs between sexes.