Depth-dependent microskeletal features modify light harvesting in Turbinaria reniformis corals

Coral skeletal morphology plays a crucial role in modulating light exposure in symbiotic algae, thereby influencing photosynthetic performance and overall energy acquisition. This function is particularly important in environments with limited light availability, such as in mesophotic and deep-water reefs. However, quantifying light capture and distribution within complex coral structures remains challenging. Using optical coherence tomography and high-resolution X-ray scanning, we explored the depth-dependent bio-optical properties of Turbinaria reniformis from shallow and mesophotic environments in the Gulf of Eilat/Aqaba, Red Sea. Our results reveal distinct skeletal layers: a highly scattering superficial layer (~100 μm thick) and a deeper, more light-penetrating layer. Mesophotic corals exhibited a higher scattering coefficient and lower anisotropy of scatter, yielding increased reflectivity, thereby optimizing light use under low-light conditions. Structural features played distin..., , , # Depth-Dependent Microskeletal Features Modify Light Harvesting in Turbinaria reniformis Corals

Dataset DOI: [10.5061/dryad.41ns1rnr9](10.5061/dryad.41ns1rnr9)

## Description of the data and file structure

##### **MATLAB_codes.zip** -

contains the code files used for OCT calibration, sample analysis and Monte Carlo Simulations use in MATLAB software:

***Pre-processing & Model Setup For Monte Carlo Simulations***

1. **MC_mesh.m** – Main code. Run Monte Carlo light transport simulations on voxelized coral. Calls:
2. **makeCoralList.m** – Define optical properties for coral tissues and water.
3. **makeCoral.m** – Create tissue structures and parameter files for Monte Carlo simulation.
4. **VOXELISE.m** – Convert coral STL mesh into a voxel grid.
5. **mcxyz.c** – Simulate light propagation (called by MC_mesh.m).
6. **splitCoralLayers.m** – Splits 3D coral mesh into top/bottom layers based on height for separate optical analysis.
7. **lookmcxyz.m** – Visualizes Monte Carlo simulation ...,