Chemicals Turn Fish Into Trippy

Dead fish can be surprisingly beautiful. Hiding beneath their scales is an elegant, skeletal architecture, a complex biological scaffold that with some skill, can become art.

Adam Summers, who studies vertebrate biomechanics at the University of Washington, takes photos of the insides of fish as part of his research. But the process is a lot more involved than snapping a pic with a cellphone. His pictures can take days to produce, and they reveal the intricate bony or cartilaginous infrastructure inside marine creatures like rays, skates, and fish. Summers’ work is now featured in an exhibit at the Seattle Aquarium that pairs each photograph with a poem.

Summers follows a standard, decades-old procedure to visualize the different types of tissue. First, you start with your organism – say, a dead fish. Next, you follow a few fixation steps that both preserve tissues and make them more permeable to dyes and enzymes.

Then it’s time to color the different tissues. Summers uses Alcian Blue to stain cartilage, and Alizarin Red S to dye the bony bits. Next, you clear away the fish’s flesh with a digestive enzyme called trypsin (trypsin doesn’t attack collagen, the fiber that holds skin and bone together), and bleach out dark pigments with hydrogen peroxide. Lastly, you submerge the now-colorful organism in glycerin, a clear and colorless solution that renders the fish transparent except for the colored bits.

Then you take its picture. Summers uses a macro lens on a DSLR and places the submerged specimens on a color-corrected LED table.

The results, as you can see, are exquisite.