Avizo fire 9

The whole head of the Heloderma suspectum was dissected from the body at the base of the skull, wrapped in Parafilm and imaged directly in a Nikon XT H 225 scanner (macro-CT, Nikon Metrology, Tring, UK). Osteoderm samples were dissected and washed 5 times in ddh2O then 5 times in 70% ethanol and left to dry for 48 hours. The non-mineralised soft tissue was removed using a scalpel blade. An A Series Compact LASER micromachining system (Oxford Laser, Oxford, UK) was used to cut out a cylinder 1mm wide. This cylinder was then cut to incrementally smaller cylinders of 500 µm diameter, then 100 µm diameter, then finally 65 µm in diameter. The thinner, upper part of this series of cylinders was imaged using either a ZEISS Xradia 520 Versa (micro-CT, 500 and 100µm diameter cylinders) or a ZEISS Ultra 810 X-ray (nano-CT, 65 µm cylinder) microscopes (Carl Zeiss X-ray Microscopy Inc., Pleasanton, CA). The raw transmission images from both X-ray CT imaging experiments were reconstructed using a commercial image reconstruction software packages (Zeiss XMReconstructor, Carl Zeiss X-ray Microscopy Inc., Pleasanton, CA, and CT Pro 3D, Nikon Metrology, Tring, UK), which employ a filtered back-projection algorithm. The 3D reconstructed volumes of the samples were segmented and analysed using Software Avizo Fire 9.2 (Thermo Fisher Scientific, USA).