Spiny dogfish shark denticle in context

From a distance, the skin of sharks may appear smooth. But if you could feel a shark’s skin you would notice that it feels smooth if you run your hand from the head to the tail but rough (like sandpaper) in the opposite direction (from tail to head). This is because shark skin is covered in tiny sharp scales called dermal denticles. These denticles have multiple functions, including directing the flow of water across the skin to decrease turbulence (making swimming more efficient and stealthy for sharks to sneak up on prey) and resist the ability of parasites to latch onto the skin.

The dogfish shark denticle was one of the first digital 3D models that we created, based on images of actual dogfish shark denticles viewed through a dissecting microscope at the highest magnification. Because they’re so small, it is really difficult to get a sense of their 3D structure. In the literature, there were only views from particular perspectives, not a full 3D model. By creating a digital 3D model of a denticle, we were not only able to create dynamic digital visualizations but also 3D print the model 100x larger than life size, which allows students to feel the shape of a structure they would otherwise not even be able to see.

However, if a student only had the model of a denticle, it would be difficult for them to guess what it is and understand how denticles are arranged on a shark’s skin. To solve this, 3D Anatomy Studios member Michael Fath created this illustration of a shark dermal denticle in context. The focal illustration of an individual denticle identifies the key parts of the denticle, the focal illustration of the shark’s skin shows how the denticles are arranged and oriented on the skin’s surface, and the illustration of the whole shark shows where on the shark we took a denticle to use as a reference for creating the 3D model.

Illustrated by: Michael Fath, MS

3D denticle model reference by: Aaron Olsen, PhD

Edited by: Aaron Olsen, PhD

Software used: Adobe Illustrator, Blender

License: CC BY-NC-SA 3D Anatomy Studios