Communication (biology)

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The communication concept in biology can on the one hand (character mediated) on the interactions between cells , tissues , organs and organisms for the purpose of behavior coordination but also to the transmission of information relating within an organism, and also to the transmission of signals and payload information between two or several individual organisms.

Internal communications

Communication is a basic condition of all living things. All living systems are designed in such a way that they gain energy in circular processes with positive feedback . These processes are carried out by cells. In the case of more highly organized living beings, they consist of a cell nucleus that is highly complex in its structure and functions . This is surrounded by a cell fluid in which a large number of highly organized bodies, so-called organelles , are embedded. There are many interactions between them and the cell nucleus, but also between the organelles themselves; they are constantly communicating with each other. This cell content is enclosed by a membrane which, thanks to its structure and specific permeability properties, shields the inside of the cell from the influences of its outside world, but at the same time enables a controlled exchange of substances, the latter being another form of life-promoting communication. Both the chemical components of these cells and the chemical processes taking place in them are essentially the same in all living things. The diversity and diversity of the organisms that can develop from them has its starting point in different genetic determinations in the cell nuclei. The development program stored there has several functions: It is the blueprint for the entire organism - be it a single cell or a human. It also contains a network plan in which the process of implementing this construction plan is defined step by step. And finally, it plays the role of the construction manager by providing the instructions for the "network plan-compliant" implementation steps of the construction plan. This implementation of the blueprint stored in the genes takes place - to put it very simply - in that the genes transfer their information to certain components in the cell plasma at the respective times in the network plan by means of chemical translation processes ( transcription and translation ) , which in turn lead to changes and transformation processes within of the cell or certain reactions with the environment of the cell, e.g. neighboring cells. The directionality and precision with which these cellular processes take place are made possible and guaranteed by a subtle network of communicative feedback. The most important ways in which cells react for more complex organisms are cell reproduction and the formation of new cell organisms.

Cell proliferation

All more highly developed living things are multicellular. The development there takes place through cell division ( mitosis ). Here, the original cell doubles and thus forms the beginning of a cell network which, depending on the construction and network plan laid down in the cell nuclei, continues in further cell divisions that run in the same way. Where this happens, one can usually observe that the replicating cells differentiate more and more. Depending on their position in the resulting overall organism, they develop to different functions: Similar specialized cells combine to form cooperating cell associations, which are referred to as tissue (e.g. connective, bone, muscle tissue). The individual organs are then built up from such, mostly different tissues, for example a skeleton , skin , muscles , connective tissue , glands, blood and lymph vessels , nerves and much more in the more highly developed living beings . No matter how differently the cell aggregates develop in an organism, nothing changes in the structure of their cell nuclei. The blueprint, which remains the same in the nuclei of all cells of the cell network, initiates an organism with differentiated functions via biochemical communication processes . At every point of the developing cell network there is feedback with the main plan for the organism laid down in the nuclei of the cells, which enables the individual cells to develop their specific, system-compliant characteristics and to make themselves the appropriate component in their place .

Formation of cell organisms

In more highly developed organisms, a cell type ( germ cell ) has developed which has the same cell nucleus as the cells described above, but which has a different cell division behavior. It enables the new combination of one's own hereditary information with that of a species- specifically identical cell of another organism and thus becomes the starting point of a living being that differs from the two original organisms in a way that cannot be individually foreseen. In addition to the internal differentiation of the individual organisms that develops in the course of normal cell reproduction in biochemical communication processes, the pairing of genetic development programs of different origins adds a new communicative element, an innovative interaction of cells to form independent cell groups in the true sense of the word.

Communication between cell clusters

Wherever cell clusters are formed, their development usually goes hand in hand with functional differentiation. Specialized subsystems within an overall organism therefore prove to be useful for life, because they allow better use of life opportunities that its environment offers it. The higher the degree of its division of labor, the more indispensable the coordinated interaction of the specialized subsystems becomes. In vertebrates, as the most highly developed organisms, the proper interaction of all functionally specialized subsystems ( sensory and body organs, limbs ) is achieved by three distinct but multifaceted peripheral networks, the endocrine system and two neural systems with different functional tasks . All three functions are controlled, coordinated and controlled to varying degrees by a central organ, the brain.

  • The endocrine system ensures that the biophysical and biochemical conditions are established, maintained and, if necessary, readjusted, under which the body organs can optimally fulfill their specific functions. This is achieved with the help of mechanisms that are known as control loops with negative feedback or homeostasis and the functionality of which can be illustrated in a simple manner using contemporary room heating : If the temperature at a certain sensor falls below a set target temperature, the radiators open of the temperature-controlled room valves for the inflow of warm water from the heating system. As soon as the heat they radiate has brought the temperature of the room back to its setpoint, the heating valves throttle the heat supply to the radiators. The endocrine system is a network through which cell structures communicate with one another using chemical messengers, so-called hormones . Hormones are produced, stored and released into the bloodstream everywhere in the body, but above all in certain body organs, the glands , which are distributed in different places in the body . Via this they are distributed throughout the body, but only trigger reactions in places that are genetically designed for them. Hormones can therefore be described as chemically coded messages that can only be read by the cells of their respective target organs. For this they are equipped with special receptors. These are specific molecules into which the hormone molecules fit into a lock like a key with the peculiar teeth of his beard. If the key fits in the lock, the hormonally encrypted message can trigger reactions in individual cells or cell groups.
  • The neural networks each consist of a special type of cell: the nerve cells or neurons. Nerve cells have three different functions: They can take in information from outside or inside the organism, they can pass this information on to places in the organism, where they trigger appropriate reactions and they can, connected to networks, store information, with other information on new, Connect complex information units and keep them available for use when needed. At the neural level, the interplay of the subsystems of an organism is established by two peripheral networks: One of the two networks, the so-called autonomous or vegetative nervous system , in close cooperation with the endocrine system outlined above, regulates bodily activities that are generally not the will of the individual subject. Like the endocrine system, it ensures that the vital body functions of the internal organs such as the heart and vascular system, respiration, secretion of the glands, digestive system , heat regulation of the skin and other things are maintained, adapted to external influences and kept in balance. The autonomic nervous system differs from the endocrine system in its reaction speed. While the endocrine system, due to the relatively slow spread of the released hormones in the blood, can only react relatively slowly and with upward and downward swings over time, the neural network takes account of the organism's need for rapid reactions. Another task of this network, which is of a different nature, is to physiologically produce a rapid readiness for reaction of the body in situations threatening the organism or in stress-generating challenges by mobilizing all available power reserves for fighting the "emergency" and not consuming power in this Organs is interrupted. The other, so-called somatic nervous system , primarily enables random, coordinated and controlled processes in the musculoskeletal system. With afferent signal strands, it supplies the brain as a control center with information about the location, position and constitution of the connected cell structures, as well as about environmental issues that are vital for the organism. On the other hand, via its efferent signal strings, it transports the reaction commands resulting from an analysis of this data in the control center to the connected limbs. In contrast to the endocrine system and the autonomic nervous system, what is characteristic of the somatic system is that it is only responsive in the waking state. Above all, however, the somatic nerve network can be used to direct the entire organism towards goals that lie outside of itself and their sometimes emphatic pursuit. Endocrine and autonomous systems then have to follow these initiatives within the framework of their physiological possibilities.
  • The endocrine and the two peripheral networks require a control system that makes specifications for the endocrine system and the autonomic nervous system for a continuous comparison of the fluctuating actual values ​​in the system with the life-compatible setpoint values ​​and which uses the somatic nervous system to align the organism with life-serving goals and the finally all three systems coordinated. The brain, as the central nervous system, takes on this task . The three main processing services of this central nervous system consist firstly in an interpretation of the incoming impulses in terms of their teleonomic significance, secondly in the saving of recallable significant stimulus constellations, called memory, and thirdly in the connection of current stimulus patterns with already stored stimulus experiences, which is the basis of the Represents learning.

External communication

The central and peripheral information and communication systems, which enable the interaction of the specialized subsystems in complex organisms, also create important prerequisites for communication between the organism and its environment. Sensory organs, the brain and the somatic nervous system are together essential for information absorption, information processing and, above all, for communicative actions expressed in conscious movements. The processes in the endocrine and vegetative control system are reflected in their feedback to the central nervous system in a variety of ways in emotionally registered sensibilities and have a lasting effect on the perception of an organism and, as a result, on communication with its environment.

Sense organs

External communication is made possible by sensors that respond to certain environmental stimuli. In a more highly developed, increasingly complex form, they are called sensory organs. They form the bridges between an organism and its environment.

  • The most important bridges to the world for plants consist of photo , thermo and mechanoreceptors that can absorb physical environmental stimuli , as well as receptors that respond to chemical stimuli. A plant usually needs a specific combination of light, warmth, moisture and nutrients to grow . If the sensors signal the presence of this special constellation of environmental conditions to a plant germ, the plant's growth process is set in motion. As a stationary organism, it needs an orientation where it can find the vital quanta of light, heat, moisture and nutrients. The special organs provided for this purpose - roots and foliage together with the supporting skeleton made of stems or trunk and branches - are directed in their growth by appropriate mechano and chemosensors in the directions where they are most likely to find the required growth factors. If the environmental conditions change in the course of growth, sensors initiate appropriate reactions: If the heat is too great, many plants change the assimilation and evaporation surface of their leaves; Certain plants close their flowers when it rains to protect their stamens. Trees change their normally vertical direction of growth in order to achieve better lighting conditions for the necessary photosynthesis. Some plants do not have their own self-supporting skeleton that they carry light and warmth. They compensate for this deficiency with mechanoreceptors in the branches of their tendrils , which cling to objects in response to contact stimuli and thus align themselves properly.
500,000 scent glands of the female silk moth ( Bombyx mori L.) were needed to elucidate the molecular structure of the bombykol.
Structural formula of Bombykol , the first clearly chemically identified insect pheromone, a sex attractant of the silk moth ( Bombyx mori ).
  • In the animal kingdom it is essentially photo, thermo, mechano and chemoreceptors with which these living beings connect with their environment. What is different and novel compared to the sensory organs of plants consists in the development of the neural system of stimulus processing. The transformation of very different stimulus qualities into a uniform language made up of chemoelectrical impulses ( action potential ), on the one hand, allows their comprehensive evaluation. On the other hand, it enables sensors of the same type to be interconnected to form sensory complexes with a much greater differentiation capacity. Both allow a much more precise and specific evaluation of the living environment. The sensory organs of animals, which form the bridges to the world, are extremely differently developed in terms of their efficiency. In the sense that responds to light stimuli, it ranges from the registration of mere light values ​​above a certain strength via colors, patterns and textures to three-dimensional films from a mobile, high-resolution stereo color camera. The reception of mechanical stimuli can take place via different senses. However, not all animals have each of these senses and their respective performance also differs between the different species. Some of the mechanical stimuli are recorded as acoustic impulses in the form of tones and noises, whereby the limits of what is audible vary greatly from species to species. Another part of physical stimuli, which can overlap with the acoustically perceptible ones in border areas, is perceived with the sense of touch via the skin or hair as touch or pressure, pain, via thermoreceptors as warmth or cold. The sensitivity to tactile stimuli is not only different from species to species, but especially in highly developed animals it is distributed very differently over the body surface. As a special mechanical stimulus in a large number of animal species, gravity is recorded by the sense of balance as an orientation in space. Mechanical stimuli are finally also - if present - scanned by the musculoskeletal system and the internal organs of animal living beings as a position determination and stress signal. Chemical stimuli (e.g. sexual attractants from insects), which differ from animal species to animal species, are finally recorded in volatile form as smells via the nose, and in soluble form as taste sensations via the tongue. If sensually perceived stimuli exceed an intensity that threatens to damage the organism, the organism is warned by pain sensations by special nociceptors inside or on its periphery.

Stimulus-response pattern

Stimulus-reaction patterns are genetically anchored mechanisms that enable an organism to instinctively satisfy needs that manifest themselves in it - primarily for the extraction of life-sustaining and growth-promoting energies from its environment.

  • Simple stimulus-reaction patterns : In its simplest form, a genetically determined reaction that is available in the organism or a fixed sequence of reactions is triggered by responding to very specific stimulus constellations, so-called key stimuli. These reactions are called instinctive movements or hereditary coordination. The apparatus that filters out this special constellation of stimuli from the abundance of environmental influences is known as the innate trigger mechanism. He is also genetically fixed. The reactions triggered by it persist or repeat themselves in the same way, if or as long as the stimuli are received and the organism has sufficient energy reserves for the reactions. Illustrative example is the paramecium (Paramecium): In constant motion, it takes its environment only two specific stimuli. If it encounters any object on its path, the same escape movement is always triggered. This consists of a backward movement followed by a renewed forward movement at a different angle. On the other hand, if the animal encounters food, the otherwise automatic escape reflex does not occur . At the same time, the previous sequence of movements is stopped in order to be able to take in food.
  • Optional stimulus-response pattern : Another, somewhat more complex stimulus-response pattern is characterized by the fact that the genetic blueprint of an organism provides not only a specific solution scheme for coping with life, but a more or less extensive range of options, which, depending on the external circumstances that the organism encounters in the course of its life can be activated. This type of genetic information is called an open program. Adaptation processes are thus the ontogenetic realization of the most suitable among the possibilities provided by the open program. A vivid example of this type of stimulus-response pattern is a divided dandelion plant , one half of which was planted in the lowlands and the other half in the high mountains. The two hereditary plants developed so differently that one could believe that they were two different species. The plant grown in the lowlands shows a tall, vigorous growth, hairless leaves and a short root. The plant in the high mountains, on the other hand, shows a compact growth, its leaves are hairy and it has comparatively deep roots. If the descendants of the dandelion plant, which is located in the high mountains, are then moved back to the lowlands, they immediately show the appearance of the genetically identical lowland plants.
  • Stimulus-reaction pattern with success feedback : Stimulus-reaction patterns of the type described above reach a further level of complexity when one or more additional sensors are added that register information about the result, success or the course of the reaction or reaction sequence, on their trigger mechanism or return the appetite integrated in the reaction pattern and modify its signals if necessary. Examples of this are aversion signals such as pain sensations occurring in the course of the reaction process, which can lead to the reaction being terminated, or confirmation signals which can intensify a reaction. Typical forms of this feedback reaction pattern are facilitating through practice, sensitizing , getting used to, getting used to and shaping.
    More developed living beings are endowed with a more or less diversified range of reactions and behaviors that they are innate with. In most cases, however, it can be observed that these reactions and behaviors are initially even slower and less accurate than after repeated repetition. Through practice, processes are facilitated, which first help them to achieve a species-preserving and expedient fluency, security and speed. It is based on nothing other than the described feedback.
    Repeated reactions triggered by key stimuli, for example touch stimuli - such as escape reactions - can also lead to the exact opposite if the sensor picks up signals at the end of the reaction process that the triggered reaction was apparently not necessary, a key stimulus that might initially signal danger apparently not really a real one Posed a threat to the organism. In this case one speaks of the organism becoming accustomed to certain stimulus situations, which, as the 'experience' conveyed by the sensor teaches, makes reactions superfluous in an entirely expedient and economic way. If a stimulus configuration that is obviously not in need of reaction changes even very slightly, the familiarization scheme is no longer in force. The original key stimuli act unchecked again.
    In yet another contrast to habituation, habituation stands. It describes changes in reactions that occur when certain stimulus situations and the behavior patterns triggered by them become a “dear, perhaps indispensable habit”. The conservation value of this process lies in an increased selectivity for the exploitation of situations which are "from experience" particularly advantageous or pleasant for the organism.
    Another selective process is what is known as embossing. It creates an irreversible connection between a reaction to a stimulus situation to which the living being is exposed once or only a few times, often at the beginning of its life. The subjects of an imprint are mostly social behaviors such as the follow-up reaction of newly hatched refugees , the rivalry between the animals and sexual behavior.
  • Concatenation, branching and shortening of stimulus-reaction patterns : The complexity of the stimulus-reaction patterns described above gains a further dimension with the higher development of the organisms, if they are connected in series to form sequences. In these cases, the reaction triggered by a key stimulus does not yet lead to a species-preserving and expedient end result, but merely strives towards a stimulus situation that triggers a further reaction and so on. Example: A tree falcon flies around searching for prey - first sequence. The falcon encounters a flock of starlings and, after climbing high above them, performs a special flight maneuver aimed at blasting a single star from the swarm - second sequence. Only when this succeeds does the raptor have reached the situation in which a further behavior, namely hitting the prey, becomes applicable - third sequence. It is then followed by other sequences, first that of plucking and then that of eating up the prey - the actual target action. The animal masters all of these movements as soon as it is able to fly, without instruction.
    The stimulus-reaction chains can also branch out in that they lead the organism into situations in which different reactions can be triggered. As an example of this, Lorenz named after experiments by Tinbergen the sticklebacks, which, if they have found a milieu controlled with the help of a previous reaction chain, start building nests there, depending on the situation encountered, possibly fighting rivals there or courting a female they encounter.
    The species-preserving advantageous advantages of such a reaction structure are, on the one hand, that they make the way in which the organism reacts more flexible because it absorbs further information about its relationship to the environment, which can direct its reaction process in other ways. The other advantage is that the sequential stimulus-response sequences evidently lead the organism from more general, easier-to-find trigger situations to more specific ones, which in themselves would not be so easy to find.
  • Conditioning of stimulus-response patterns : The triggering mechanisms of the stimulus-response patterns can be expanded by combining a natural response-triggering stimulus with another stimulus that normally cannot trigger the reaction. If this happens repeatedly and consistently, it can lead to the fact that the associated stimulus alone and directly becomes the trigger for the reaction. Classical conditioning . This expansion of the stimulus-response pattern is of eminent importance, on the one hand, because with it the organisms have to a certain extent discovered the principle of causality that prevails in nature and can use it proactively to adapt to their environment. on the other hand, because the triggering of genetically programmed reactions can be arbitrarily manipulated.
  • Virtualization of stimulus-reaction patterns : A final further development of stimulus-reaction patterns based on the discovery of causality is those that are initially not perceptible from the outside, but only run virtually in the neural network of the central nervous system. We humans are familiar with these processes. We always experience it when we think about solving a problem before we tackle it practically. In our mind's eye, we then let the intended event run in its conceivable possibilities and check in advance how individual influencing factors, which are either to be expected or which we have available, could affect the course of the event. With a view to the desired goal, we then adjust our actual actions to these influencing factors. Such processes are not specifically human. For example, even with apes and crows .

Human-specific features

The instinctual reactions, which are based on homeostasis and stimulus-reaction patterns and, in more highly developed animals, can be conditioned through experience, usually enable the living beings to adapt optimally to their respective external environment and function extremely clearly, reliably and not susceptible to interference in terms of their life-serving determination. Compared to this seemingly perfect fit, people are comparatively inadequately prepared to cope with their living environment. This is first expressed in the fact that the human organism is still largely unfinished when it is born. Rather, he is dependent on the care and guidance of his parents or other members of his species for many years. In addition, there are the inadequately developed instincts in highly civilized people. In most cases, recorded stimuli do not automatically trigger specific, life-enhancing reactions. The human drive structure is therefore not firmly fixated on the satisfaction of specific life needs, but largely open-ended. This openness to goals ultimately corresponds to an openness to stimuli of the human sensory system that is otherwise not found in the animal kingdom. If only what is important to animals is what serves their instinctive needs, everything can become important to humans. This corresponds in a special way with an instinct that appears in animals, if at all, mostly only temporarily: the exploration instinct, a state of excitement which urges activity and which accompanies man throughout his life in the waking state.

Individual evidence

  1. Günther Witzany: Biocommunication and Natural Genome Editing. Springer, Dordrecht 2010, ISBN 978-90-481-3319-2 .
  2. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980.
  3. Niels Birbaumer, Robert F. Schmidt: Biological Psychology. 3. Edition. Springer, Berlin 1996, ISBN 3-540-59427-2 .
  4. ^ Jacques Monod: Chance and Necessity. 3. Edition. Piper, Munich 1971, ISBN 3-492-01913-7 , p. 130.
  5. ^ Jacques Monod: Chance and Necessity. 3. Edition. Piper, Munich 1971, p. 227.
  6. Manfred von Lewinski: How lonely do people stay? Pro Business, Berlin 2006, ISBN 3-939000-70-1 , p. 5.
  7. Niels Birbaumer, Robert F. Schmidt: Biological Psychology. 3. Edition. Springer, Berlin 1996, p. 18.
  8. Frederic Vester: Thinking, Learning, Forgetting. 4th edition. dtv, Munich 1979, p. 58.
  9. ^ Gunther Witzany (ed.): Natural Genetic Engineering and Natural Genome Editing. Blackwell, Boston 2009, ISBN 978-1-573-31765-8 .
  10. Niels Birbaumer, Robert F. Schmidt: Biological Psychology. 3. Edition. Springer, Berlin 1996, p. 40.
  11. Manfred von Lewinski: How lonely do people stay? Pro Business, Berlin 2006, p. 8.
  12. Niels Birbaumer, Robert F. Schmidt: Biological Psychology. 3. Edition. Springer, Berlin 1996, p. 68.
  13. Niels Birbaumer, Robert F. Schmidt: Biological Psychology. 3. Edition. Springer, Berlin 1996, p. 64.
  14. ^ A b Philip G. Zimbardo, Siegfried Hoppe-Graff: Psychology. 5th edition. Springer, Berlin 1992, ISBN 3-540-53968-9 , p. 119.
  15. Niels Birbaumer, Robert F. Schmidt: Biological Psychology. 3. Edition. Springer, Berlin 1996, p. 267.
  16. Manfred von Lewinski: How lonely do people stay? Pro Business, Berlin 2006, p. 42.
  17. Albert Gossauer: Structure and reactivity of biomolecules. Verlag Helvetica Chimica Acta, Zurich 2006, p. 134, ISBN 978-3-906390-29-1 .
  18. ^ A b Philip G. Zimbardo, Siegfried Hoppe-Graff: Psychology. 5th edition. Springer, Berlin 1992, p. 143.
  19. Manfred von Lewinski: How lonely do people stay? Pro Business, Berlin 2006, p. 43.
  20. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 76.
  21. Jakob von Uexküll, Georg Kriszat: Forays through the environments of animals and people. Rowohlt, Hamburg 1958, p. 49.
  22. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 90.
  23. Manfred von Lewinski: How lonely do people stay? Pro Business, Berlin 2006, p. 31.
  24. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 95.
  25. LKonrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 97.
  26. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 102.
  27. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 106.
  28. a b Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 84.
  29. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, p. 85.
  30. Konrad Lorenz: The back of the mirror. 4th edition. dtv, Munich 1980, pp. 128-133.
  31. Manfred von Lewinski: How lonely do people stay? Pro Business, Berlin 2006, p. 38.
  32. Jakob von Uexküll, Georg Kriszat: Forays through the environments of animals and people. Rowohlt, Hamburg 1958, p. 27.
  33. Arnold Gehlen: Man, his nature and his position in the world. 7th edition. Athenaeum, Frankfurt am Main 1962, p. 53.
  34. Manfred von Lewinski: How lonely do people stay? Pro Business, Berlin 2006, p. 76.

See also

Voice feeling , phytohormones , animal language , zoo semiotics , biosemiotics