Mimicry is what businesses everywhere are doing

Mimicry and mimetic - extreme adaptation to the environment

Hello! Have you ever wondered why the zebra has stripes? How do squids change color? And why are fire salamanders bright red or black and yellow? Aren't they eaten right away? This video is about animal warning and camouflage. You will get to know camouflage colors, mimesis, warning clothes, mimicry and molecular camouflage mechanisms in single cells. Many animals protect themselves with camouflage coloring. Some even change these with the season, for example the mountain hare. It is brown in summer and white in winter. Others change their color even faster. The common squid has cells in its skin that contain various pigments, or dyes. These cells expand or contract. The squid can choose which pigment cells it wants to present at the moment. Of course, he tries to match his surroundings in terms of color. He can stretch and contract the skin cells at any time and completely spontaneously in order to hide from his enemies. But there are much better camouflage specialists out there. Some animals use what is known as “mimeticism”, which is a special case of camouflage. Not only the color, but also the shape of the body is adapted to the environment. For example, stick insects resemble green or brown branches. They have long, thin limbs and a wood-like grain. Even their eyes are barely noticeable, and some species have thorn-like structures on their legs. This special camouflage color gives them a selection advantage over less well camouflaged insects. They are less likely to be recognized and eaten by enemies. Another example of mimesis is the Indian leaf butterfly. It pretends to be a dry leaf. Its wing undersides imitate the drawing of leaf veins and leaf parts. The outlines of the wings even have the shape of a leaf including a petiole. Other animal species are much more conspicuous. They have warning gear in bright warning colors such as red, yellow or blue. Of course, only very poisonous, defensive or inedible animals such as the red- or yellow-black fire salamander can afford this conspicuous coloration. He has glands on his back from which he injects a neurotoxin in case of danger. Predators who have had this unfortunate experience avoid their conspecifics. Individuals of his kind therefore have a selection advantage. They are eaten less often. Some animal species make use of these warning signals even though they are neither poisonous nor defensive themselves. This false warning is called "mimicry". Have you ever seen small insects that are striped black and yellow and seem to float in the air in one place? Although they look like this, they are not wasps, but harmless, non-toxic hover flies. Since they are similarly colored so that they can be confused, they also have a selection advantage over other fly species. They are avoided by predators. Not only large animals, but even single-celled organisms camouflage themselves. Parasites, for example, hide in the body from the antibodies of the immune system. They use molecular camouflage mechanisms. This is trypanosoma. Trypanosoma is a single cell. It is transmitted by the tse-tse fly and causes sleeping sickness. Let's take a closer look at its surface. Here we find surface proteins, so-called antigens. These are specifically recognized in the blood by the antibodies. The antibodies react with the antigens and destroy the pathogen. After a short time, however, Trypanosoma sheds its antigens and forms new ones. Our immune system no longer recognizes the pathogen. This is called molecular camouflage: the formation of a new antigen pattern that is no longer recognized by antibodies of the immune system. An effective protection and therefore also a selection advantage. Let's summarize again: Many animals use camouflage for protection. If their shape is perfectly adapted to the environment, this is called mimetics. If antigens on the surface of pathogens are changed and no longer recognized by the immune system, one speaks of molecular camouflage mechanisms. Predators are deterred by warning hoods with eye-catching colors and patterns. Some animals just imitate them. They use mimicry. But what is the zebra doing now? Does it camouflage or warn? It disguises itself. Its stripes blur in front of the complex eye of the tse-tse fly. Thus it is almost invisible to the flies and therefore stung less often. Since the tse-tse fly, in addition to the unicellulars of sleeping sickness, also transmit the pathogens of the often fatal Nagana epidemic, the zebras have a clear selection advantage. During your next walk and good observations, you will in any case know who is camouflaging themselves with mimicry or who is warning with mimicry. I hope you learned a lot. Bye and see you next time.