In the coral bushes at a depth of 30 meters, a 15-centimeter-long mantis shrimp is lying motionless in the cave, and in a few moments, a coral crab roams to the nest of the mantis shrimp, and the crab runs rampant without hesitation, unaware of the danger in front of it. Seeing the prey appear, the mantis shrimp began to get excited, constantly waving a pair of tentacles, quietly lifting a pair of huge paddle-like limbs, and then lightning pounced on the crab.
With two imperceptible blows and two loud "bangs, bangs", two large holes had been opened in the thick carapace of the coral crab. Seeing this scene, no matter how calm you are, you will be stunned.
<h2 class = "pgc-h-arrow-right" > boxing champion</h2>
One can't help but ask, how did such a small creature accumulate such a great power in an instant? Biologists have uncovered this secret in recent years. In order to catch prey and defeat competitors, the mantis shrimp used its powerful ejection ability and connecting rod "arm" to become the fastest punching champion in the animal kingdom.
Mantis shrimp belong to the crustacean, order of the order Schizophora, inhabiting offshore waters around the world. Mantis shrimp is neither a shrimp nor a praying mantis, but has the characteristics of both. Its body consists of a shrimp-like nodal abdomen, carapace, swimming feet, tentacles, and huge chelated appendages that look like a folding knife. In terms of appearance, it is very similar to the mantis on land, hence the name mantis shrimp. Biologists classify two main species: spear-limbed mantis shrimp and hammer-limbed mantis shrimp. The appendages of the spear-limbed mantis shrimp are arrow-shaped and used to stab swimming fish; the appendages of the hammer-limbed mantis shrimp are rounded at the tip and can break the thick carapace of the animal.
In recent years, scientists have conducted quantitative studies on the speed of the mantis shrimp. According to the video recorded by the high-speed camera, they found that the mantis shrimp appendage moved at a speed of more than 80 kilometers per hour, and the maximum acceleration was more than 10,400 times the acceleration of the Earth's gravity. If a boxer can always hit at this acceleration during the boxing process, his punching speed will soon reach the escape speed required to escape from the earth's gravity!
The scientists also found that the mantis shrimp released more than 100 times the amount of hitting energy that its "arm" muscles could produce. In order to accumulate this explosive power, the mantis shrimp uses shrinkage and hunting to slowly accumulate muscle energy, and then release this energy suddenly.
In general, many carnivorous aquatic animals, including carnivorous fish, have a hunting instinct that allows the mouth of carnivorous fish to open rapidly, but the mantis shrimp's elastic limbs (a shelly paddle-like limb that stores muscle energy) are unique. The mantis shrimp squeezes the muscle tissue at the end of the paddle-like limb tightly together, causing the muscles to bulge, and after catching up with the prey, the mantis shrimp's paddle-like limb quickly returns to its original form, and then pushes its limb forward with explosive force. The ejaculation actually comes from the bar arm that connects the mantis shrimp's limbs to the rest of the "arm".
When a mantis shrimp rapidly hits a target with its limbs, an unusual bubble is created between its limbs and the surface of the hit, and these bubbles collapse rapidly. The video shows that the killing effect of the mantis shrimp is caused by this huge force, known as the air cavitation phenomenon.
Cavitation is often the main culprit in the destruction of motorboat thrusters. Let's see how the cavitation of the air cavitation that caused the destruction of the motorboat was formed. The vortex created by the pump and the boat thruster often leads to the appearance of vortex cavitations, and when the steamboat splits the water surface and moves rapidly in the water, the pressure of its wake will be lower than the air pressure of the water, and the water near the moving object is actually boiling. When the surrounding water returns to normal, the force formed by high pressure and bubble collapse is enough to knock out many small pits on the surface of hard objects such as stainless steel.
The radius of cavitation bubbles formed when the mantis shrimp hits an object with its limbs ranges from one-half centimeter to several hundred centimeters, and within this radius, the pressure per square centimeter can reach hundreds of kilograms. When the bubble drifts out of the low pressure area it produces, the high pressure shrinks it, and its shrinking volume causes the pressure and water vapor temperature inside the bubble to rise continuously. This high-heat, high-pressure water flow can cause devastating damage to objects.
Therefore, cavitation bubbles formed between the limbs of the mantis shrimp and the shell of the prey play a crucial role in destroying hard targets. Of course, the cavitation bubble also brings some trouble to the mantis shrimp itself, the limbs of the mantis shrimp often have some pits and injuries, and some of its limbs are seriously damaged or even unable to directly hit the prey, all of which are caused by cavitation bubbles. However, no matter how severe this injury is, the mantis shrimp mend this damage by periodically shedding the exoskeleton. Scientists believe that the rapid hitting action of the mantis shrimp and the resulting air cavitation phenomenon are the two main reasons why the mantis shrimp are able to break the hard shell of crustaceans.
<h2 class="pgc-h-arrow-right" > the most complex eye structure</h2>
In addition to the nickname boxing champion in the animal kingdom, the mantis shrimp has another world-famous, with the most complex eye structure in the world. The reason why its eye structure is so complex is inextricably linked to its habitat. Mantis shrimp tend to inhabit deeper, dark waters, and the light that seeps in this water layer is dark blue, and the eyes of mantis shrimp have evolved to be more and more complex in order to be able to see the objects around them.
Like insects and crustaceans, mantis shrimp are compound eye structures, which are very different from the eyes of vertebrates. One view is that every pigment in the mantis shrimp's eye can respond to a color, just as hair cells in the human cochlea can respond to an audio. In this case, a larger chromatographic range allows it to see more colors.
There is no doubt that mantis shrimp can see colors, its color vision range can cover all the spectrum that humans can see, and can also see ultraviolet and infrared rays that we humans can't see, and some mantis shrimp can even achieve 16 kinds of color discrimination. As for how the mantis shrimp observe the world, scientists still don't know, because they still haven't figured out how the mantis shrimp's eyes work.
The mantis shrimp's unique eye structure allows them to see polarized light, and many animals also have this visual ability, such as some spiders, insects and migratory birds, and birds can even use polarized light to navigate. However, mantis shrimp can not only recognize linearly polarized light, but also see circularly polarized light (this light wave travels in a spiral, either to the left or to the right). This unique visual ability of the mantis shrimp is attributed to the fact that it has 6 rows of numerous small eyes in its compound eyes. Based on the arrangement of light cells in some small eyes, Justin Marshall, a photosensitive neurobiologist at the University of Queensland in Australia, believes that the unique visual structure of mantis shrimp allows them to see circularly polarized light.
So Marshall and his colleagues tested the mantis shrimp to find out if the crustacean could distinguish between different light rays. They found that 3 of the 4 mantis shrimps could correctly identify the left-handed circular polarized light, while 2 of the other 3 mantis shrimp could distinguish the right-handed circular polarized light. Marshall believes that circularly polarized light vision of mantis shrimp may play a very important role in finding mates. Because mantis shrimp contain a lot of sugar in their carapace, some of their carapace reflects roundly polarized light and looks like sparkling jewelry. Mantis shrimp use circularly polarized light to communicate with potential mates that are not easily detected by predators because other animals may not be able to see this particular light.