Animal Stories: CCTV10

Author: Gao Changling / Country: Mainland China
Publisher:
Publish Date: 2005-07-01
Features: This is an ancient and massive species that has survived on Earth for 67 million years. Despite its simple body structure, it is highly practical in every aspect. Although it appears elegant and beautiful, it harbors limitless killing potential. It is a testament to the wonders of creation yet also the best example of the theory of "survival of the fittest." It is the jellyfish. The dazzling "flowers of the water."
Jellyfish come in a variety of species, with diverse shapes, colors, sizes, and distributions. However, most share certain common traits. The main component of a jellyfish's body is water, composed of two embryonic layers separated by a thick mesoglea layer. This layer is not only transparent but also aids in buoyancy. Below the umbrella-shaped body, numerous long tentacles grow. These tentacles serve not only for hunting and movement but also for floating.
The movement of jellyfish is unique. Their horizontal movement is achieved by expelling water through their bodies, propelling them forward. From a distance, it appears as if a round umbrella is swiftly drifting through the water. Vertical floating is controlled by a special gland in the umbrella, which releases carbon dioxide to inflate it. When jellyfish encounter predators or strong storms, they release the gas and sink underwater. Once the danger subsides or the storm calms, they can reinflate within minutes and resume floating.
P151 Some jellyfish emit light, depending on a remarkable protein called aequorin found within them. When this protein mixes with calcium ions, it produces a strong blue light. The brighter the light, the more aequorin is present. For example, comb jellies, while swimming in the ocean, can emit blue light from their eight radial canals, resembling a dazzling, colorful ball. Another example is the ribbon jellyfish, which has several parallel light bands distributed around and within its body. As it swims, these bands ripple gracefully with the waves.
Because of this, when people encounter jellyfish swarms on a sunny day at sea, they are often mesmerized by the spectacular sight: the sea waves like snow, the blue surface dotted with many elegant umbrella-shaped bodies, glowing faintly with pale green or purplish-blue light, some even with a rainbow-like halo.
P152 The fierce "warriors" of the jellyfish may appear beautiful and gentle, but they are actually quite ferocious, often playing the role of powerful predators. Jellyfish have a wide range of prey, mostly consisting of plankton, but some also hunt fish or even their own kind. As a result, they are equipped with highly advanced "weapons": their long tentacles, which are also their digestive organs. The surfaces of these tentacles are covered with nematocysts, which, upon contact with prey, shoot out like tiny harpoons, piercing the prey's body. They can even effortlessly penetrate the shells of crabs. Then, they inject toxic substances into the prey. This is the jellyfish's deadly "equipment," making it impossible for their prey to escape the fatal effects of the venom. The tentacles then tightly grasp the prey, retract them, and attach them to the polyps below the umbrella. Each polyp secretes enzymes that rapidly break down the proteins in the prey's body. Since jellyfish lack respiratory and circulatory systems, only a primitive digestive system, their captured food is immediately digested and absorbed in the cavity.
But as the saying goes, "Every coin has two sides." Even the formidable and deadly jellyfish have natural enemies: a sea turtle can freely swim through jellyfish swarms, easily tearing their tentacles with its mouth, leaving the jellyfish unable to resist and becoming the turtle's meal. However, the most terrifying enemy is humans, who turn these fierce jellyfish into "cold jellyfish salad" or "vinegar jellyfish heads" at the dinner table whenever they see fit.
P153 The "flesh of Tang Monk" will no longer be limited to mythology. Immortality has been a pursuit of humans since ancient times. Since Xu Fu failed to obtain elixirs with five hundred boys and girls, and Tang Monk was protected by Sun Wukong, people could only seek longevity through praying to gods, alchemy, and good deeds, or through modern healthcare and wellness. But longevity is not the same as immortality. As the poem goes, "After the willows and flowers, another village appears."
Scientists have discovered through detailed observations of certain jellyfish that, under normal circumstances, most jellyfish spend most of their lives in the larval stage, with a very short adult phase. After reproduction, they rapidly age and die. However, the only exception known to humans is a jellyfish living along the Italian coast. After mating, they can change their cell structure and return to the larval stage, repeating this cycle. These jellyfish are immortal.
What allows these old cells to return to a youthful state? Can humans use this to study medicine or other things? If so, perhaps jellyfish hold the key to unlocking the door to eternal youth, and in the future, the "flesh of Tang Monk" may no longer be confined to mythology.
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