Meeting Abstract

S10-8   14:00 - 14:30  Different traits at different rates: The effects of dynamic strain rate on structural traits in biology Anderson, PSL; Kawano, SMK*; University of Illinois Urbana-Champaign; The George Washington University smkawano@gwu.edu https://sandykawano.weebly.com/

Phenotypic and functional diversity are shaped by physical laws that govern how organisms develop and evolve. To study comparative organismal biology, we need to quantify this diversity through the use of biological traits (definable aspects of the morphology, behavior, and/or life history of an organism). Traits are often assumed to be immutable properties that need only be measured a single time in each adult, but organisms often experience changes in their biotic and abiotic environments that can alter trait function. In particular, structural traits represent the physical capabilities of an organism and may be heavily influenced by the rate at which they are exposed to physical demands (‘loads’). For instance, materials tend to become more brittle when loaded at faster rates which could have negative consequences for structures trying to resist those loads (e.g., brittle materials are more likely to fracture). In the following talk, we will address the dynamic properties of structural traits and present case studies that investigate how dynamic strain rates affect these traits in diverse groups of organisms. First, we will review how strain rate affects deformation and fracture in biomaterials and demonstrate how these effects alter puncture mechanics in systems such as snake strikes. Second, we will discuss how different rates of bone loading affect the locomotor biomechanics of vertebrates and their ecology. Through these examinations of diverse taxa and ecological functions, we aim to highlight how rate-dependent properties of structural traits can generate dynamic form-function relationships in response to changing environmental conditions. Findings from these studies serve as a foundation to develop more nuanced ecomechanical models that can predict how complex traits emerge and, thereby, advance progress on defining the Rules of Life.