Document Type


Date of Original Version



Biological Sciences


The ability to produce a strong byssal attachment is one key to the competitive dominance of mussels on many rocky shores. The byssus is composed of numerous extracellular collagenous threads, which in turn can be divided into proximal and distal regions that are distinct in ultrastructure and chemical composition. Our current understanding of the mechanical design of mussel byssus is largely based on quasi-static testing, where a fiber is slowly extended to failure. Mussels in nature, however, inhabit a dynamic environment where repetitive loads can be applied on short time scales. This study evaluates the mechanical properties of the threads of Mytilus californianus subjected to repeated subcritical loads and a range of strain rates. A subset of these mechanical tests was also performed on the threads of three other mytilid species. Results indicate that subcritical loading alters the mechanical properties of a thread in a manner that is dependent on the extension applied, and that thread stiffness and damping increase with increasing strain rate. Overall, this study provides insight into the mechanical design of a byssus that is subjected to dynamic loading.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.