Figure 3.

Examples of age-0 Lake Sturgeon, Acipenser fulvescens, otolith polymorph quantification results from single individuals within each experimental treatment (i.e., control [15 °C, 1000 μatm pCO₂], pCO₂ [15 °C, 2500 μatm pCO₂], temperature [22 °C, 1000 μatm pCO₂], temperature + pCO₂ [22 °C, 2500 μatm pCO₂]) including (a) images of sagittal otoliths at ×10 magnification, (b) Debye–Scherrer diffraction patterns collected using X-ray microdiffraction, and (c) percent polymorph composition (i.e., aragonite, vaterite, calcite) by otolith weight. Examples were chosen to highlight the variability in otolith polymorph composition observed among some individuals and the potential for large amounts of aragonite to be present in sturgeon otoliths that have previously long been considered to be comprised entirely of vaterite.