|
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese|
MOST IMPORTANT SCIENTIFIC DISCOVERIES
Comparative anatomy. History and essence of scientific discovery
Directory / The most important scientific discoveries Cuvier rightly considered the founder of comparative anatomy, or as they say today - comparative morphology. But Cuvier had predecessors in this field - in particular, Vic d'Azir. The merit of Cuvier - and, moreover, unsurpassed by anyone - lies in the fact that he widely and generously expanded the base of arguments in defense of the doctrine of analogs, homologues and correlation, deepened the interpretation of problems of morphology, perfectly formulated its first "laws" ... Georges Leopold Christian Dagobert Cuvier (1769–1832) was born in the small Alsatian town of Montbéliard. The boy was struck by early mental development. At the age of four he was already reading. Reading became a favorite pastime, and then a passion of Cuvier. His favorite book was Buffon's Natural History. Cuvier constantly redrawn and colored illustrations from it. At school he studied brilliantly. At the age of fifteen, Cuvier entered the Karolinska Academy in Stuttgart, where he chose the Faculty of Cameral Sciences. Here he studied law, finance, hygiene and agriculture. But most of all he was attracted to the study of animals and plants. Almost all of his comrades were older than him. Among them were several young people interested in biology. Cuvier organized a circle and called it "academy". Four years later, Cuvier graduated from the university and returned home. His parents were old, and his father's pension was barely enough to make ends meet. Cuvier learned that Count Erisi was looking for a home tutor for his son. Cuvier traveled to Normandy in 1788, on the eve of the French Revolution. There, in a secluded castle, he spent the most turbulent years in the history of France. The estate of Count Erisi was located on the seashore, and for the first time Cuvier saw alive the marine animals familiar to him from the drawings. He dissected these animals and studied the internal structure of fish, crabs, soft-bodied, starfish, and worms. He found with amazement that in the so-called lower forms, in which the scientists of his time assumed a simple structure of the body, there is an intestine with glands, and a heart with blood vessels, and nerve ganglions with nerve trunks extending from them. Cuvier penetrated with his scalpel into a new world in which no one had yet made accurate and careful observations. He described the results of the research in detail in the journal "Zoological Bulletin". When in 1794 the son of Count Erisi entered his twentieth year, Cuvier's service ended, and he again found himself at a crossroads. Parisian scientists invited Cuvier to work in the newly organized Museum of Natural History. In the spring of 1795, Cuvier arrived in Paris. He advanced very quickly and in the same year took the chair of animal anatomy at the Sorbonne University in Paris. In 1796, Cuvier was appointed a member of the national institute, in 1800 he took the chair of natural history at the College de France. In 1802 he took the chair of comparative anatomy at the Sorbonne. The first scientific works of Cuvier were devoted to entomology. In Paris, studying the rich collections of museums, Cuvier gradually became convinced that the system adopted in science Linnaeus does not quite correspond to reality. Linnaeus divided the animal world into 6 classes: mammals, birds, reptiles, fish, insects and worms. Cuvier proposed a different system. He believed that in the animal world there are four types of body structure, completely dissimilar to each other. Deep knowledge of animal anatomy allowed Cuvier to restore the appearance of extinct creatures from their preserved bones. Cuvier became convinced that all the organs of an animal are closely connected with each other, that each organ is necessary for the life of the whole organism. Each animal is adapted to the environment in which it lives, finds food, hides from enemies, takes care of its offspring. If this animal is a herbivore, its front teeth are adapted to pluck grass, and its molars are to grind it. Massive teeth grinding grass require large and powerful jaws and corresponding chewing muscles. Therefore, such an animal must have a heavy, large head, and since it has neither sharp claws nor long fangs to fend off a predator, it fights off with its horns. To support a heavy head and horns, a strong neck and large cervical vertebrae with long processes to which muscles are attached are needed. To digest a large amount of low-nutrient grass, a bulky stomach and a long intestine are required, and therefore a large belly is needed, wide ribs are needed. This is how the appearance of a herbivorous mammal looms. "An organism," said Cuvier, "is a coherent whole. Individual parts of it cannot be changed without causing changes in others." Cuvier called this constant connection of organs among themselves the "correlation of the parts of the body." The task of morphology is to reveal the patterns that govern the structure of the body, and the method that allows you to establish the canons and norms of organization is a systematic comparison of the same organ (or the same organ system) through all sections of the animal kingdom. What does this comparison give? It precisely establishes, firstly, the place occupied by a certain organ in the body of an animal, secondly, all the modifications experienced by this organ at various levels of the zoological ladder, and, thirdly, the relationship between individual organs, on the one hand, and also by them and the organism as a whole - on the other hand. Cuvier qualified this interconnection with the term "organic correlations" and formulated it as follows: "Each organism forms a single closed whole, in which none of the parts can change, so that others do not change." "A change in one part of the body," he says in another work, "affects the change in all others." Examples illustrating the "correlation law" can be given as many as you like. And no wonder, says Cuvier: after all, the whole organization of animals rests on him. Take some large predator: the connection between the individual parts of his body hits his eyes with its obviousness. Fine hearing, sharp eyesight, a well-developed sense of smell, strong limb muscles that allow jumping towards prey, retractable claws, dexterity and speed in movements, strong jaws, sharp teeth, a simple digestive tract, etc. - who do not know these "relatively developed" features of a lion, tiger, leopard or panther? But look at any bird: its entire organization constitutes a "single, closed whole," and this unity in this case manifests itself as a kind of adaptation to life in the air, to flight. The wing, the muscles that set it in motion, the crest on the sternum, the cavities in the bones, the peculiar structure of the lungs, which form air sacs, the high tone of the heart, the well-developed cerebellum that regulates the complex movements of the bird, etc. are strongly developed. something in this complex of structural and functional features of the bird: any such change, says Cuvier, will inevitably affect to one degree or another, if not all, then many other features of the bird. In parallel with correlations of a morphological nature, there are physiological correlations. The structure of an organ is related to its functions. Morphology is not divorced from physiology. Everywhere in the body, along with correlation, another regularity is observed. Cuvier qualifies it as subordination of organs and subordination of functions. The subordination of organs is associated with the subordination of the functions developed by these organs. However, both are equally related to the way of life of the animal. Here everything should be in some harmonious balance. Once this relative harmony is shaken, then the further existence of an animal that has become a victim of a disturbed balance between its organization, functions and conditions of existence will be unthinkable. “During life, the organs are not just united,” writes Cuvier, “but also influence each other and compete all together in the name of a common goal. There is not a single function that does not need the help and complicity of almost all other functions and does not feel to a greater or lesser extent the degree of their energy ... Obviously, a proper harmony between mutually acting organs is a necessary condition for the existence of the animal to which they belong, and that if any of these functions is changed out of correspondence with changes in other functions of the organism, then it cannot exist. So, acquaintance with the structure and functions of several organs - and often just one organ - allows us to judge not only the structure, but also the lifestyle of the animal. And vice versa: knowing the conditions of existence of this or that animal, we can imagine its organization. However, adds Cuvier, it is not always possible to judge the organization of an animal on the basis of its way of life: how, in fact, to connect the rumination of an animal with the presence of two hooves or horns? The extent to which Cuvier was imbued with the consciousness of the constant connection of the parts of the animal's body is evident from the following anecdote. One of his students wanted to play a joke on him. He dressed up in the skin of a wild ram, entered Cuvier's bedroom at night and, standing near his bed, shouted in a wild voice: "Cuvier, Cuvier, I'll eat you!" The great naturalist woke up, stretched out his hand, felt for the horns, and, examining the hooves in the semi-darkness, calmly replied: "Hooves, horns - a herbivore; you cannot eat me!" Having created a new field of knowledge - comparative anatomy of animals - Cuvier paved new paths of research in biology. Thus the triumph of the evolutionary doctrine was prepared. Author: Samin D.K.
Artificial leather for touch emulation
15.04.2024 Petgugu Global cat litter
15.04.2024 The attractiveness of caring men
14.04.2024
▪ Texas Instruments reveals details of its 45nm process technology ▪ New type of soil discovered on the moon ▪ NEC P and V Series Digital Signage Displays ▪ Super slim button from Panasonic ▪ Could there be dark matter at the center of the sun?
▪ section of the site For a beginner radio amateur. Article selection ▪ article Transmitter for telecontrol. Encyclopedia of radio electronics and electrical engineering
Home page | Library | Articles | Website map | Site Reviews
www.diagram.com.ua |
We recommend interesting articles Section 
See other articles Section 
Latest news of science and technology, new electronics:
All languages of this page