In 1967, Ralph Taylor, one of the Museum’s fish curators, improved upon the “clearing and staining” technique by using the chemical trypsin, rather than potassium hydroxide, and revolutionized the way ichthyologists study fish skeletons. In clearing and staining, the muscles become transparent and the bones are dyed red. In the late 1970s, the technique was further developed to stain the cartilage blue, providing even more information about the development of fish from the larval stage through maturity.
This cleared and stained lookdown fish (Selene vomer) is both cartilage (blue) and bone (red) in the larval stage. Photo by David Johnson, 2008.