May 6, 2024

What Physicists Can Learn From the Unique Spiral Shape of Shark Intestines

Levin described that “the scientists of the 2021 study connected a tube to the shark intestines, and put water with glycerin– a very viscous fluid– through these pipelines. And they showed that if you link these intestines in the same direction as a gastrointestinal tract, you get a much faster circulation of fluid than if you link them the other way around. We thought this was really interesting from a physics viewpoint … One of the theorems in physics in fact specifies that if you take a pipeline, and you stream fluid extremely slowly through it, you have the exact same flow if you invert it. So we were extremely stunned to see experiments that oppose the theory. But then you bear in mind that the intestinal tracts are not made out of steel– theyre made of something soft, so while fluid flows through the pipeline, it deforms it.”
When they used a stiff material to 3D print the shapes, there was no difference in fluid circulation in one direction or the other. Printing the shapes using a softer elastomer led to faster fluid flow in one direction. Using these 3D-printed structures, the team is studying how the radius, pitch, and density of the inner structure impacts the fluid circulation.
Up till recently, robotics have been made with rigid materials and hinges. Utilizing soft products that can deform in various methods, like an octopus does, opens up an entire world of possibilities, Levin discusses, “this is one action forward in trying to comprehend the basic mechanics of the interaction between membranes and flow.” One day, this relatively easy system might manage industrial or medical gadgets.

Different kinds of sharks have intestines with various spiral patterns that favor fluid circulation in one direction. In 2021, scientists found that sharks spiral-shaped intestines work much the exact same way, preferring fluid circulation in one instructions– from head to pelvis.
We thought this was really fascinating from a physics viewpoint … One of the theorems in physics actually states that if you take a pipe, and you stream fluid extremely gradually through it, you have the exact same flow if you invert it. When they used a rigid product to 3D print the shapes, there was no distinction in fluid flow in one instructions or the other.

Different type of sharks have intestinal tracts with various spiral patterns that favor fluid circulation in one direction. Ido Levin and colleagues are recreating those shapes using a 3D printer in order to study the distinct fluid flow inside the spirals. Credit: Image courtesy of Ido Levin
Shark intestinal tracts have a special spiral shape that prefers fluid flow in one direction. By discovering about the functions of this phenomenon, physicists wish to apply the concepts to robotics and other applications.
Creator Nikola Tesla patented a kind of pipe that he called a “valvular channel” in 1920. It was built to draw fluid in one direction with no moving parts or included energy and has applications ranging from soft robotics to medical implants. In 2021, researchers found that sharks spiral-shaped intestines work similar way, preferring fluid circulation in one direction– from head to pelvis.
Ido Levin, a physicist in the laboratory of Sarah Keller at the University of Washington, ended up being thinking about the physics flow of fluid through these shark spirals. On Monday, February 20 at the 67th Annual Biophysical Society Meeting in San Diego, California, he will provide how 3D printing designs of shark intestines is assisting them find out about how these spirals work.