Meeting Abstract
Fish skin has many components that contribute to its protective, yet flexible structure. The dermis of fish skin is partially composed of highly ordered helical collagen fibers, which wrap around the body of the fish. Previous studies indicate that skin and scales have a significant effect on flexural bending stiffness and side-to-side swimming kinematics. However, when fishes swim, they also twist around their long axis, and little is known about how skin effects this torsional motion. In this study, we quantified the helical collagen fiber angles in the skin of six species of elongate fishes that twist their bodies by different amounts during swimming. We used trypsin to remove muscle and clear pigmentation of skin samples and used polarizing filters to image the fibers under a dissection microscope. From ventral to dorsal, one set of fibers points towards the anterior end and one set of fibers points towards the posterior end. Using the images, we measured the angle of the anterior and posterior pointing fibers compared to the position along the body. Understanding the effect that skin fibers have on torsional stiffness and overall body mechanics, and their relationship to swimming kinematics and lead to a greater understanding of fish swimming behavior in the natural environment.
