Meeting Abstract
The red lionfish, Pterois volitans, is native to the Indo-Pacific region, and has quickly proliferated along the Western Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. It has been shown to negatively affect the ecosystems it invades by decreasing biodiversity. Lionfish have 13 dorsal stings (the defense apparatus) which are comprised of a spine of mineralized collagen surrounded by a dermal sheath. The spines are tapered and have anterolateral grooves that create an anchor-like cross-section and store venom. We hypothesized that the cross sectional shape of the spines optimizes their ability to resist bending. For this study, we quantified lionfish spine flexural stiffness (EI), which takes into account both shape (I) and material (E), at varying locations of lateral point load. Due to the anchor-like cross-section, we predicted that EI of the spine will increase when the lateral point load is applied at the anteromedian ridge, where I will be the largest. We generated a digital 3D model of the 12th dorsal spine of a P. volitans and printed magnified (11.46x) resin models. We applied point loads at two locations on the spine models and compared them to models of I-beams. I-beams are frequently used in construction because of their high I, which increases EI relative to a solid beam. Similarly, lionfish spines have a large portion of their cross-section area located away from the neutral axis allowing for high I and EI with less material. Mechanical testing of lionfish spines is essential to understand the form and function of unique shapes found in nature.
