Structural and mechanical properties facilitate shock wave damping by helmet-like orbital hoods in snapping shrimp

Snapping shrimp damp the shock waves they produce and use as weapons with a helmet-like structure termed the orbital hood. Here, we ask how structural and material properties contribute to shock wave damping by orbital hoods in Alpheus heterochaelis. Using tensile mechanical testing, we find orbital hoods are approximately half as stiff as the carapace and have twice the capacity for viscous energy dissipation. Microstructural features likely contribute to tissue-specific mechanical properties: the endocuticles of orbital hoods have almost twice as many lamellae as those of carapaces, despite being half as thick, suggesting a mechanism for enhanced material mobility underlying viscous behavior. Using material properties from mechanical testing and geometric data from microCT, we developed finite element simulations of interactions between shock waves and orbital hoods. These simulations predict orbital hoods reduce shock wave-induced strain and stress in the neural tissues of shrimp by ..., , # Data from: Structural and mechanical properties facilitate shock wave damping by helmet-like orbital hoods in snapping shrimp

Dataset DOI: [10.5061/dryad.2v6wwq02w](https://doi.org/10.5061/dryad.2v6wwq02w)

## Description of the data and file structure

The orbital hoods of snapping shrimp are the first biological armor system shown to protect an animal from blast-induced neurotrauma by damping shock waves, a discovery that prompts questions about their mechanism of function. Here, we ask how the structural and material properties of orbital hoods contribute to shock wave damping in *A. heterochaelis*.

### Files and variables

#### File: SLS_optimize_fixedTau_fun.m

**Description:** MATLAB code for fitting the linear elastic model to the experimental data we collected for snapping shrimp exoskeleton samples

#### File: viscoelastic_fitting_submission.m

**Description:** MATLAB code for fitting the linear elastic model to the experimental data we collected for snapping shrimp exoskel...,