Why are people so dark and twisted

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For many, these animals are nothing but slimy, disgusting sea creatures, including some that can be dangerous to us humans with their poison. What connects us humans with these transparent beings consisting of 98 percent water?

Jellyfish - they have more in common with us than you think.

Collagen - a successful patent for evolution is in our bones

More than 700 million years ago, single-cell organisms were formed, including sponges, corals and jellyfish. Your body is made up of many individual cells that are connected to one another. This cell association is supported by a protein, collagen. It consists of many intertwined and tightly wound fibers that are extremely stable due to their arrangement. This material has even greater tensile strength than steel.

In jellyfish, the biological all-purpose glue is in the gelatinous support layer. The patent has proven itself over many millions of years and is now widespread throughout the animal kingdom. Collagen can also be found in the human body - its proportion of proteins makes up up to 30 percent. No other protein is so common in our country. Bones, cartilage, tendons, ligaments, teeth and skin benefit from its properties. It helps the body to maintain its posture - without collagen we would slump.

The name of the collagen comes from the Greek and means something like "glue producing", because in the past the collagen was boiled out of bones and used as glue in woodworking. The putty containing protein is still important today: in the food industry, for example as gelatine in gummy bears, in cosmetic products as a miracle cure for firm connective tissue or as a cartilage replacement in medicine. Up until now, bovine bones were the main source of collagen. Since the animal disease BSE, researchers have been looking for alternatives and discovered the jellyfish as an ideal source of raw materials.

See and be seen

But the jellyfish is not only literally in our bones, one of our sensory organs also has its origin in these transparent animals: our eyes! Looking at the environment with your own eyes assumes that light rays that hit the eye stimulate light-sensitive receptors and thus nerves, which transmit signals to the brain. Some jellyfish also have eyes. However, they have no brain and can therefore no longer process the information. However, they can perceive light or dark and react accordingly, for example by swimming towards a light source. These light-sensitive organs of vision probably originated before the brain. Scientists assume that there were initially, around 570 million years ago, individual light-sensitive cells, some of which developed into special light receptors. They are the basis for all other eye types that have very likely developed several times and independently of one another in the course of evolution: for example, the compound eyes of insects, the pit eyes of snails, the pinhole eyes of the nautilus or the lens eyes of vertebrates. There are eyes for spatial vision and for a 360 ° view, visual organs for colors, for light-dark contrasts or for better night vision. As diverse as the eye types may seem at first glance, they share a genetic basis. What they have in common is the gene for the growth of the seeing sense organs: it is called Pax. Experiments have shown that activation of this gene, for example in the wings of flies, causes eyes to grow. Conversely, no seeing sense organs developed when Pax was switched off by an artificial intervention. This genetic switch can be found in all seeing living beings; it controls the development of the eyes. So they are all related to each other: the simple light-sensitive sensors of the jellyfish up to the color-seeing lens eyes of humans.

Human eye - ingenious patent of evolution.

The inner jellyfish

Every human embryo goes through various stages during its development - from the fertilized egg cell to the fetus - which connect it to certain living beings. Already in the first days of his life he completed an important stage, the so-called gastrulation: The starting point is the blastocyst, a single-layer hollow sphere, the tissue of which turns inside like a cup. The gastrula is a cup-shaped germ, a bulbous shape that consists of two layers of cells. At this stage, the human embryo resembles a jellyfish, but it soon evolves. The jellyfish have already reached their final shape with the "cup shape".

Like all animal multicellular cells, the jellyfish, which belong to the hollow animals, also develop in this way: The gelatinous aquatic creatures consist of two single-layer layers of tissue, between which there is a cell-free layer that contains, among other things, the formative collagen. At the opening of the "cup" are tentacles that help to transport the food into the (original) mouth. Indigestible food is also released through the same body opening.

© Text: Susanne Wagner