As a predator of the oceans,
Sharks always give the impression of sharp teeth and ferocious character
But in fact,
The shark body has a lot of magical structures unknown,
For example, its unique digestive system.
For more than a century, the understanding of sharks' digestive systems, and the effects of their eating and excretion behaviors on other species in the ocean, has relied on planar anatomical maps. Today, researchers have performed high-resolution 3D scans of the intestines of nearly 60 species of sharks, greatly advancing understanding of the shark's feeding and digestion processes.
Using a computed tomography (CT) scanner at the University of Washington's Friday Harbor laboratory, the researchers created a 3D image of the intestines of a shark specimen at the Natural History Museum in Los Angeles, USA.
They first surgically removed the entire digestive tube from 32 sharks, which were a variety of different spiral intestines: columnar, reeled, up or down, and then filled all the intestines with liquid and freeze-dried to maintain their natural shape. Then, using computed tomography, a virtual 3D model of the intestine was created.
In experiments that simulated these gut digesting food, the researchers found that it took about 35 minutes for the fluid to flow through the spiral intestine in a normal direction. However, when they inverted the spiral-shaped intestine, they found that the fluid passed through both funnel types twice as long as before.
That is, the shark's intestines deliver food in a spiral-like manner, without the need for muscles to push the food. Unlike humans and most other animals, we rely on the muscle contractions of the intestines to push food forward, like squeezing toothpaste.
What are the benefits of this spiral delivery of food? The answer is a significant reduction in energy consumption. Sharks do not eat for days or even weeks after a big meal, and this spiral way of transporting food makes the speed of food through the intestines very slow, which provides the shark's digestive system with sufficient time to extract nutritional value. The researchers speculate that such a slow digestion process may also drastically reduce the amount of energy consumed.
This magical digestive tract has greatly amazed researchers: Isn't this the check valve invented by Tesla?
When it comes to Tesla, is everyone's first reaction now that it is an electric car?
However, many people may not know that the name of this brand was created in honor of physicist Nikola Tesla.
Nikola Tesla invented the Tesla valve in 1920, a check valve structure that cleverly utilizes the principles of fluid mechanics without moving components. A century later, scientists discovered that nature had already placed Tesla's genius invention inside the shark's digestive system, becoming the secret weapon in the guts of these top marine predators.
The researchers say the engineering field can learn from this technology to control the flow of liquids with minimal energy consumption, for example, it can be used to filter microplastics in sewage treatment processes.