Clearing and staining
Clearing and staining specimens promotes observation of specimens’
skeletal structures and specifically allows us to measure internal
skeletal traits. We therefore cleared and stained 683 fish specimens, in
preparation for future measurements. We fixed pupfish specimens in 95%
ethanol, skinned them, and then immersed the specimens in 5% buffered
formalin and double-stained the specimens with alizarin red and alcian
blue as outlined in (Dingerkus & Uhler, 1977). After, we suspended the
specimens in glycerin and took lateral and dorsal photos with a Canon
EOS 60D digital SLR for downstream digital measurements.