Birds, like mammals, belong to the class of animals, but despite this unifying feature, birds have a number of abilities and characteristics that significantly distinguish them from mammals.
For many, the most obvious difference that comes to mind is feathers and wings. Yes it is. Plumage is characteristic only of birds, otherwise they would not be able to fly. Birds belong to vertebrates, and this unites them with mammals, fish, and reptiles, allowing them to be included in the huge biological kingdom - Animals.
Birds originated from reptiles and they owe this to their distant parent – lizards. The first bird-like creature was the bird Archeopteryx. She lived about 120 million years ago and was like a lizard, the size of a pigeon, that walked on its hind legs, had wings, but could not fly. It also had a beak, feathers, set teeth, but a long, twenty-vertebral lizard tail. 
Flights were gliding and difficult for Archeopteryx, but it had long, sharp claws, with the help of which the lizard easily climbed trees and made short flights. Following from this, we can say with confidence that the ancestor of modern birds was half lizard and half bird, so the relationship of these two classes of animals is obvious.
Who are the animals and who are the birds?
Animals are living organisms united into one large kingdom. There are about 34 types of animals in this kingdom, which in turn are divided into 50 million species of living things.
Birds are the same animals, but their bodies are covered not with hair, but with feathers. The birds' forelimbs were modified into wings, which gave them the ability to fly. In total there are about 10,000 species of different birds. 
Comparative characteristics of animals and birds
If birds and animals belong to the same biological kingdom, then the question arises about their differences. What is the difference between these representatives of the animal kingdom?
It must be said that all birds are warm-blooded animals who can fly. This extraordinary ability determined and shaped the morphological and physiological characteristics of birds, and also adapted their body for flight. As a result of long-term evolution, the forelimbs of birds were transformed into wings, and the legs became more massive and muscular. The bird needs massive legs for successful takeoff and landing, and the tail serves as a directional control.
Animals, unlike birds, can be either warm-blooded (mammals) or cold-blooded (reptiles, fish, amphibians). Some types of animals have no shelter at all (flatworms, tunicates, sponges).
The body of a bird, unlike an animal, is covered feathers. The plumage allows you to create greater streamlining of the body during flight, and at low temperatures, the feather better retains the heat of the bird’s small body. The animal's body, in turn, has a wide variety of coverings. It can be epidermis, scales, chitinous cut, shell, skin or just wool.
Bird bones are incredibly strong, despite being light compared to animal bones. During the flight, the unity and immobility of the body is of great importance. It is ensured by the fusion of the vertebrae of all parts of the bird’s spine, with the exception of the cervical. Birds, compared to animals, have a fairly long and elongated neck, and also have a keel. Many types of animals, not including chordates, have no internal skeleton at all. 
The digestive system of a bird begins with a beak, which is not the case in animals. Metabolism is accelerated, which is required for food to be quickly processed, while providing the bird with the necessary amount of free energy spent on flight. The circulatory, respiratory, and excretory systems operate in accelerated mode.
The mammals and birds we see today are the product of the evolution of two different phyletic lineages of amniotes: the synapsids, or beast-like creatures, and the sauropsids, or typical reptiles. The entire history of terrestrial vertebrates is mainly a history of rivalry between these groups, in which first one or the other of them gained the upper hand. This is due to the fact that some of the “evolutionary achievements” of these animals are different, and did not appear in both groups at the same time. Mammals are the dominant terrestrial vertebrates in the modern fauna. They now occupy many of the adaptive zones that previously belonged to dinosaurs, and were vacated after the extinction of the latter, when modern mammals were small, insignificant animals hiding on the forest floor. Living mammals have also mastered ecological niches that never belonged to dinosaurs: for example, the niches of large marine predators and planktivores (whales), or flying insect hunters (chiropterans). In the terrestrial environment, only invertebrates surpass modern mammals in biomass, and the same can be said about the number of individuals (thanks to the huge number of people). The very name “mammals” contains a reliable diagnostic feature of this class: the presence of mammary glands. All mammals (both sexes) have mammary glands, but other animals do not. But it is worth remembering that we cannot deny the presence of mammary glands to many extinct animals that are not mammals, although they are their relatives. This progressive feature, which allows for a kind of care for the offspring, developed in the ancestors of mammals due, on the contrary, to the primitive structure of their skin - slightly keratinized, soft, rich in glands, that is, similar to the skin of amphibians, but not typical reptiles. Other mammalian skin glands include sweat glands (used for thermoregulation), odorant (modified sweat glands, used for communication), and sebaceous (used to lubricate hair). Hair in the modern world is also the prerogative of mammals. Unlike fish scales and bird feathers, hair is a derivative of ectoderm, not mesoderm. The oldest type of hair is sensitive (vibrissae). Subsequently, the hair spread throughout the body and began to perform a heat-insulating function (down and guard hair). However, it should be noted that there are mammals without hair, sweat and sebaceous glands. Other keratin derivatives of mammalian skin are claws (and their modifications - nails, hooves), horns, scales (on the tail of rats and almost everywhere in pangolins). The main feature of mammals in the skeletal structure is the presence of three pairs of auditory ossicles. The quadrate bone turned into an anvil, the articular bone into a malleus (the stirrup remained a stirrup). Since part of the jaw apparatus became part of the middle ear, the dentary is the only bone of the lower jaw connected by a joint directly with the squamosal bone of the skull (with the squamosal of the temporal bone). The former angular bone of the lower jaw became the tympanic bone, supporting the eardrum. The mammalian skull is non-kinetic, that is, the upper jaw is motionlessly connected to the braincase. The zygomatic arch on the right and left is one, synapsid, formed by the zygomatic and squamosal bones. The condyle of the occipital bone is paired, as in modern amphibians. The braincase is large, and its inner surface is made up of bones that are not in contact with the brain in other vertebrates (except birds), and are located only on the outer surface (frontal, parietal, squamosal).
There are usually seven cervical vertebrae. The joint between the skull and the first vertebra (atlas) performs mainly nodding and a little lateral rotation; twisting is impossible due to two condyles. Like all modern amniotes, the body of the atlas has fused with the body of the second vertebra (epistrophy), forming its odontoid process. The joint between the first and second vertebrae provides rotation, and between the remaining vertebrae - lateral rotation, raising and lowering the neck. The ribs in the cervical region are reduced and fused with the vertebral bodies, forming transverse costal processes. The trunk region is divided into the thoracic region with fully developed ribs, the sternal part of which in most mammals is cartilaginous, and the lumbar region, in which the ribs are shortened and fused with the vertebrae, also forming transverse costal processes. Reduction of the ribs in the lumbar region is associated with the presence of diaphragmatic breathing in mammals, which requires a soft abdominal wall. The sternum is segmented. There are from 2 to 5 sacral vertebrae, but only the first 2 of them are true sacral vertebrae, associated with the pelvic girdle, and the rest are fused caudal. There are from 3 reduced to 50 full caudal vertebrae. The tail in mammals, even if it is long, is often a rather thin formation, of little importance in movement, compared to the tail of fish and some reptiles. The exceptions are cetaceans, sirens, kangaroos and jerboas. The shoulder girdle in its original form, which is now observed only in monotremes (platypus, echidna), is represented by scapulae, anterior coracoids, posterior coracoids, clavicles and interclavicles (presternal). In marsupials and placentals, only the scapula and clavicles remain, and in placentals, specialized for running, the clavicles are lost, which allows the scapula to move back and forth, increasing the stride width of the forelimb. It is difficult to say anything special about the skeleton of the shoulder. The skeleton of the forearm is represented by the radius and ulna, which in the original version are movable relative to each other, and their “overlapping” allows the hand to rotate. But in many running mammals, these bones grow together and even fuse, which makes it possible to reduce the mass of the forearm with the same strength, neglecting the rotation of the hand that is unnecessary in this case. The skeleton of the hand consists of the proximal and distal rows of carpal bones, metacarpal bones and phalanges of the fingers. The initial number of fingers is 5; as it decreases, which reflects specialization for running, the first finger is lost first; the minimum possible number with a fully developed limb is 1.
The pelvic girdle consists of the ilium, ischium and pubis. The ilium in mammals is long and directed obliquely back and down from the sacrum, being a functional extension of the back. This is due to the vertical bends of the back when galloping (by the way, apart from mammals, only crocodiles are capable of galloping among modern animals). The right and left pubic bones in most cases fuse along the midline, forming a closed pelvis. The head of the femur is bent medially, which gives the femur a vertical position. The skeleton of the lower leg initially consists of independent tibia and tibia, which, however, are motionless relative to each other (rotation of the foot, if possible, is carried out in the ankle joint). In running mammals, the fibula can be greatly reduced and fused with the tibia. The skeleton of the foot consists of the proximal, middle and distal rows of tarsal bones, metatarsal bones and phalanges. The original phalangeal formula of the fingers and toes in mammals is 2 – 3 – 3, exceptions are rare. Mammals have some specific muscle structure features. Only they have facial muscles, which are divided into sphincters (closers of the holes in the skin existing on the head) and dilators (expanders of these holes, intertwined at one end with the sphincters). Facial muscles sometimes reach a high degree of specialization (in elephants, pigs). The functions of the facial muscles are collecting food (in particular, sucking milk), visual signaling, turning the ears, closing the nostrils, etc. The facial muscles are homologues of the constrictor muscle in reptiles. The muscles that control the lower jaw are highly differentiated. It is raised by the pterygoid, masseter and temporal muscles. It is very important that in the presence of food between the cheek teeth, the masticatory muscle loads the jaw joint to compress, and the temporal muscle to unclench. Countering their friend in this sense, they apply enormous force to the food without threatening to destroy the jaw joint. By coordinating the work of all three muscles on both sides of the head, mammals carry out the transverse movements of the lower jaw necessary for chewing. The lower jaw is lowered by the digastric muscle and sometimes by some muscles associated with the shoulder girdle (sternocleidomastoid or its derivatives). Mammals often have highly developed subcutaneous muscles, allowing, in particular, horses to drive away flies, and hedgehogs to curl up into a ball. Another muscle unique to mammals is the diaphragm, which divides the body cavity into the thoracic and abdominal. The diaphragm is a dome with its apex pointing forward. As muscle fibers contract, the diaphragm flattens, increasing the volume of the chest cavity and pressing on the abdominal organs (this is why there are no ribs in the abdominal wall of mammals).
The main features of the mammalian digestive system are associated with adaptation to thorough processing of food in the oral cavity. The oral cavity is separated from the nasal cavity by the secondary palate, which allows for simultaneous breathing and chewing. The lips help in grasping the food, and the cheeks prevent it from falling out of the mouth from the side. The presence of a secondary palate, lips and cheeks allows the cubs to suckle milk. Teeth are divided into functional groups: incisors, canines and cheeks. Of the cheek teeth used for chewing, premolars have two generations, and molars have one. The number of certain teeth is expressed by a dental formula, in which only half of the head is considered (right or left), the teeth of the upper jaw are written in the numerator, and the teeth of the lower jaw are written in the denominator of the fraction. For example, the dental formula of a person (adult) is 2123 / 2123. The reduction in the number of teeth generation is associated with the development of occlusion - occlusion, a specific precise closure of the cheek teeth, which is a necessary condition for chewing. If the teeth were replaced many times, starting from a time when the animal was still very small, occlusion could not develop. In reality, the teeth appear almost simultaneously, ready to occlude, when the size of at least the head is close to its final size. This, in turn, is possible thanks to milk feeding or intrauterine nutrition of a young individual that is devoid of teeth and has a small size. Why don't teeth continue to be replaced in adult mammals? Apparently, the fact is that all modern mammals are descendants of small, short-lived animals - contemporaries of dinosaurs. In modern mammals, teeth often age before anything else. These are the costs of the past. The way out of this situation is different - the constant growth of teeth as they wear out. Such teeth have high crowns, open roots and are called hypselodont. High-crowned teeth without constant growth with closed roots are hypsodont, short-crowned teeth are brachiodont. Depending on the shape of the chewing surface, cheek teeth are divided into tribosphenic (having sharp ridges for cutting and blunt tubercles for grinding - this is the original type), secodont (with a strong development of cutting edges for cutting muscles, ligaments, etc.), bunodont (blunter tuberculate) , for compromise crushing of a variety of foods), selenodont (lunate, for grinding coarse fibrous plant food), lophodont (comb, for solving the same problem). The happiness of having such highly specialized teeth would be incomplete if it were not for the powerfully developed salivary glands. Mammals have them not only parietally, as in other vertebrates, but also behind the wall - parotid, submandibular and sublingual. Their secretion can be used not only for processing food in the oral cavity, but also for catching it (anteater) or thermoregulation (dog).
When chewing, food must move in the mouth accurately and correctly. This is done with the help of the buccal muscle (one of the facial muscles) and the tongue, which in mammals is penetrated by muscles in all directions and can perform complex precise movements not associated with the movements of the hyoid bone. It is interesting that the language of mammals is not even homologous to the language of other vertebrates, but is a new formation. Given this processing of food in the oral cavity, it is not surprising that the stomach of most mammals is very simple. In one case (monotremes) it is lined with glandular epithelium of the esophageal type and is used only for storing food, in another (carnivores) it is lined with intestinal type epithelium and also performs the function of digestion, in the third (pigs, humans) it has lining of both types. The main exception to the rule of simplicity of the stomach of mammals is ruminants and some other animals similar to them in the nature of digestion (sloths). These animals have, in addition to a “real” stomach with intestinal-type epithelium, several glandular chambers in which rough plant food is fermented by symbiotic bacteria. Bacteria process the cellulose of the feed into easily digestible substances that serve the host as a source of energy, and also produce essential amino acids and vitamins. The mammalian intestine is clearly divided into small (duodenum, jejunum and ileum) and large (cecum, colon and rectum). In carnivores, omnivores, and ruminants, the intestines are unremarkable, but in non-ruminant herbivores, such as equids, elephants, and many rodents, the cecum and colon are greatly enlarged and serve the same function as the proventriculus in ruminants. Mammals have metanephric (pelvic in nature of development in ontogenesis) kidneys, which secrete urea as the final product of nitrogen metabolism. Because urea is water soluble, mammals inevitably lose water when they urinate, just like amphibians. However, the concentrating ability of their kidneys can be very high. In kangaroo rats, which can survive on air-dried food, urine crystallizes immediately after excretion. Mammals are the only vertebrates capable of producing higher concentrations of electrolytes in their urine than in their blood plasma. The ureters carry urine to the bladder. A specific feature of the reproductive system of mammals is the retention of fertilized eggs in the oviducts. Even monotremes lay eggs with a fairly developed embryo inside, which emerges after a very short incubation. In marsupials and placentals, eggs with even more developed young (especially in placentals) are destroyed at the moment of laying. We call this process viviparity. The birth of a fetus is the phenomenon of rejection of an organism that is genetically foreign to the mother. In placentals, a temporary organ - the placenta - delays rejection, and the fetus can reach a very high degree of maturity. In guinea pigs, cubs differ from adults only in that they are smaller and are not able to reproduce.
The development of embryos and subsequently fetuses occurs in viviparous mammals in the uterus, which is a derivative of the terminal section of the oviduct (homologous to the shell gland of oviparous vertebrates). Both oviducts tend to unite, starting at the posterior ends. In marsupials, a primitive situation is observed in which the oviducts, uteri and vaginas are paired (the bifurcated head of the male penis is associated with the latter). Lagomorphs and proboscideans have a double uterus but an unpaired vagina. Most mammals have a bicornuate uterus with an unpaired end section - the body. Primates and many bats have a simple, unpaired uterus into which both oviducts directly open. In placental mammals, that is, not in monotremes and not in marsupials, the metabolism between the body of the mother and the fetus is carried out through a temporary organ - the placenta, which, in addition to the above-mentioned function, also prevents rejection (premature birth) of the fetus, which is genetically foreign to the mother’s body . The placenta has a maternal part (uterine epithelium hypertrophied during pregnancy) and a child part (villi of the outer extraembryonic membrane - chorion). The closeness of contact between both parts determines the efficiency of metabolism. In the epitheliochorionic placenta, the chorionic villi enter the recesses of the uterine epithelium, which remains completely intact. The villi are located scattered throughout the surface of the fertilized egg. Such a placenta is characteristic of prosimians, equids, pigs and camels. It allows the least intensive metabolism of the mother and fetus; when the placenta (the baby part of the placenta) is separated, there is no bleeding. In the desmochorionic placenta, the chorionic villi enter the connective tissue with blood vessels located under the uterine epithelium through openings in the epithelium. The villi are located on the fertilized egg in groups - cotyledons. The metabolic rate is slightly higher, and bleeding during separation of the placenta also does not occur. Such a placenta is characteristic of ruminant artiodactyls. In the endotheliochorial placenta, the chorionic villi, having penetrated through the holes in the uterine epithelium into the connective tissue, come into contact with the walls of its vessels. The metabolic rate is even higher; when the placenta separates, slight bleeding occurs. The villi are located on the fertilized egg along the zone enclosing it in a ring. Such a placenta is characteristic of carnivores. In a hemochorial placenta, chorionic villi penetrate into the lumen of the vessels through openings in the latter. The metabolic rate is the highest; when the placenta is separated, severe bleeding occurs. The epithelium of the uterus after childbirth can no longer be restored in the place where it came into contact with the child’s part of the placenta. It is thrown out and grows again. The villi form a disc-shaped zone on the fertilized egg. Such a placenta is characteristic of insectivores, advanced primates, lagomorphs and rodents.
In monotremes, the right ovary and right oviduct are much less developed than the left ones. Mammals have paired testes with appendages and paired vas deferens. In the primitive case, the testes are located in the abdominal cavity, like the ovaries. But in most mammals, the testes descend into the scrotum, taking with them, of course, the serous membranes. In such animals, spermatogenesis can occur only at a temperature lower than body temperature, which is proven by the infertility of cryptorchids and the possibility of restoring their fertility with surgical correction of the developmental defect. However, mammals without a scrotum also have no problems with spermatogenesis. There are also intermediate options: the location of the testes under the skin without the formation of a real testicular sac, or the descent of the testes into the scrotum only during sexual activity. Male mammals have accessory sex glands (in full form - vesicular, prostatic and bulbous), which produce most of the volume of sperm - substances that dilute and nourish sperm, neutralize the acidic environment of the vagina, form a plug, etc. Mammals are characterized by an unpaired penis. In monotremes it is used only for the excretion of sperm (and by the way, it has several holes), and in marsupials and placentals it is also used for urine. In the female version, the clitoris is homologous to it. Among mammals there are a very large number of species in which only females take care of their offspring. Undoubtedly, this is due to the reduction of mammary glands in males. However, it is almost certain that at an early stage of evolution, both sexes cared for their offspring equally and had equally developed mammary glands. As an exception, they can work without artificial hormonal stimulation in modern marsupials and placentals, and in the platypus, male lactation is a normal phenomenon. In mammals, males are almost always larger than females. This is apparently due to the peculiarities of mating, in which the female must be suppressed and fixed (despite this, in the everyday life of many species, females dominate). The respiratory system of mammals is arranged according to the same plan as that of amphibians. The lungs are blind-closed, but their functional surface is greatly increased due to division into small alveoli. There is one larynx - the upper one; it not only prevents water and food from entering the respiratory system, but also serves as a vocal apparatus, since it contains vocal folds. But the vocal apparatus may also have a different origin - in cetaceans it is located in the nasal passages. The breathing mechanism is fundamentally different from that of amphibians (due to the presence of ribs, the movement of which changes the volume of the chest cavity) and in reptiles and birds (due to the presence of a diaphragm). In the circulatory system, arterial and venous blood flows are completely separated. The heart is four-chambered, with one aortic arch - the left one. Both the right and left atrioventricular valves are leaflet valves. The renal portal system is absent. Red blood cells, unlike other animals, are nuclear-free.
In the structure and function of the nervous system, mammals are the most “high-tech” among vertebrates. The highest association center is the cerebral cortex, in which (only in mammals) gray matter is located on the outside and white matter on the inside. The surface of the cortex can be increased due to the formation of grooves and convolutions. At least there is at least one groove - the olfactory one, which separates the new cortex (associative) from the ancient (olfactory lobe). Due to the dominant development of the hemispheres, the midbrain is reduced, its optic lobes are reduced to the anterior (visual) colliculi. The cerebellum is well developed, but compared to the cerebral hemispheres it does not look as large as in fish and birds. There are 12 pairs of cranial nerves. The leading analyzers in mammals, in the original version, are smell, touch and hearing. But in the modern world there are many exceptions: the dominant function of vision in primates, hearing in cetaceans and bats. Even the best-seeing mammals have significantly weaker vision than birds. Apparently, the reason for this is poor vision in early mammals. Accommodation of the eye is achieved by changing the curvature of the lens. Unlike other vertebrates, mammals are not capable of moving their eyes in different directions. A third eyelid is sometimes present. In burrowing mammals, the eyes may be reduced and even hidden under the skin. The hearing aid is characterized by the presence of three pairs of auditory ossicles, as mentioned above. In marsupials and placentals, the cochlea of the inner ear is spiral, that is, only in them among all vertebrates is it rightfully called a cochlea. The tympanic bone in the primitive case is a ring framing the eardrum (which is a former part of the lower jaw, as opposed to the eardrum of other animals), and in advanced forms it forms the auditory drum, which houses the auditory ossicles. Most mammals have a well-developed, and often mobile, auricle made of cartilage and skin. The olfactory epithelium covers the mammalian ethmoid labyrinth, but not the turbinates. It is completely absent in cetaceans. In mammals covered with fur, the main organs of touch are vibrissae - sensitive hair. When hair loss occurs, the entire skin becomes an extensive receptor field. Taste buds in mammals, unlike other vertebrates, are located almost exclusively on the tongue. They are well developed due to the careful processing of food in the oral cavity. The general ecological importance of mammals is very great. Among them there are species that form a huge biomass through which significant flows of matter and energy pass. These include grazing herbivores, many cetaceans, and, in the last thousand years, humans. Only among vertebrate mammals are there landscape-forming forms: beavers, elephants and, again, people. Almost exclusively the success of the evolution of mammals is associated with the success of the youngest group of reptiles - snakes. Among mammals, there are those that occupy very specific ecological niches that are not claimed by other animals - for example, the niche of a large eater of social insects or a miner of fossil energy resources.
In the modern fauna, birds represent one of the three most significant classes of vertebrate animals, surpassing the number of mammal species, but inferior to bony fish. In terms of the total number of individuals, birds probably also occupy an intermediate position, and in terms of total biomass they are inferior to both fish and mammals, since on average birds are rather small animals. In the light of the latest paleontological data, birds can be characterized as dinosaurs that have a keel on the sternum or have lost it for the second time (we will not touch upon the diagnostic characteristics of dinosaurs here). It is this feature, and not any others, that can be confidently called uniquely avian and easily identifiable. Thus, a feature of the biology of birds is the features of the biology of dinosaurs in general plus the features of birds associated with their characteristic ability to fly (or preserved after the loss of such ability). We can say that it was flight that made birds from dinosaurs, and the need for flight and the possibility of it were associated with a decrease in body size. This explains the small, on average, size of birds, since the flight of a bird weighing more than 15 kg is associated with a contradiction between the available power and the power required for flight (the largest flying bird - Argentavis - reached a mass of 120 kg, but, most likely, was a passive soarer) . There are few flightless birds, because they experience strong competition from modern mammals, and only in their absence, as was the case in New Zealand, do they undergo powerful speciation. Most of the body surface of birds is covered with feathers, which are complicated and enlarged scales of their ancestors. Unlike mammalian hair, feathers and scales are almost exclusively mesodermal structures. Feathers can be divided into contour feathers, which determine the appearance of the bird, and auxiliary feathers. The areas of skin on which contour feathers are located are called pterilia, and the areas on which they are not are called apteria (they are absent in ratites and penguins). Auxiliary pterilia, feathers can be found in both places. The contour feather has a barrel (the part of the barrel immersed in the skin is called the quill), from which first-order barbs extend. On the first-order beards there are second-order beards that carry hooks for connecting adjacent first-order beards into a dense fan. Among the contour feathers, flight feathers are distinguished, including primary feathers, attached to the hand, and secondary feathers, attached to the forearm; steering - attached to the pygostyle (see. below), and covert feathers, called by their location head coverts, chest coverts, loin coverts, upper secondary coverts, lower tail coverts, etc. Some of the covert feathers can be semi-down - devoid of hooks and therefore not forming a fan. In ratites, all contour feathers are arranged like this. There are several types of auxiliary feathers. Down differs from a semi-down feather in that its trunk is represented only by the quill and quill, the beards of the first order diverge radially. The function of down is thermal insulation. Down may be absent altogether (woodpeckers, pigeons), confined to apteria (passeriformes), or present on both pterilia and apteria (Anseriformes, Falconiformes). (passeriformes), pteriliformes, (Anseriformes, Falconiformes). Filamentous feathers are associated with tactile receptors and, being next to the contour feathers, signal the position of the latter. Filament feathers are easy to see in pigeons with the contour feathers removed. Powder feathers are feathers that are constantly growing and constantly turning into fine dust. This dust replaces the secretion of the underdeveloped coccygeal gland in pigeons, parrots, and herons. The bristle-like feathers are similar to the whiskers of mammals and perform the same function, located on the head of kiwis and owls. In swifts and nightjars, bristle-like feathers, blocking the corners of the mouth, improve the hunting qualities of their huge mouth. Tassel-shaped feathers are located near the duct of the coccygeal gland. They are lubricated with its secretion, and then the bird smears it over the rest of the feathers.
During the life of an individual, the embryonic downy coat (which may occasionally be completely absent) is replaced by a second downy coat or immediately a juvenile one, a juvenile by the first annual one, etc., in other words, age-related and seasonal molting occurs in birds. Seasonal, at a minimum, is a complete post-breeding, and maybe also a partial pre-breeding, during which a brighter breeding plumage is acquired. When molting, new feathers are formed in the follicles and old ones are pushed out. This process requires an increase in hormonal activity of the thyroid gland. If you pull out a feather not during molting, then on the contrary, the release of the follicle from the old feather stimulates the growth of a new one (this is not possible for all birds; in predators, a new feather will not grow before the next molt). In some birds, stress molting is also possible: a frightened bird relaxes the muscles that normally hold the feather edges in the follicle, and the feathers fall out from an insignificant impact, allowing in some cases to escape from the holding hands of a predator. Covert feathers are associated with striated subcutaneous muscles, and birds can change the position of these feathers (protruding or pressing them) voluntarily, in contrast to the smooth muscle-driven hair of mammals. “You recognize a bird by its feather,” wrote B. Zakhoder, but feathered dinosaurs without signs of flight adaptations are now known. Apparently, the appearance of feathers (or down, similar to embryonic one in modern species) was caused by the requirements of thermoregulation in endothermic animals when their size decreased. In addition to participating in thermoregulation and flight, feathers can also have a signaling function, both visual, as is well known in the example of the peacock or birds of paradise, and acoustic, as in the snipe or collared grouse. Areas of skin devoid of feathers can also carry information about the species, sex and age of the bird due to its specific color and structure. Birds do not have sweat glands; only one sebaceous gland is the coccygeal gland, and even that is not developed in all species. The unfeathered covering of the legs most likely did not undergo changes compared to dinosaurs. The replacement of teeth with a horny beak - rhamphotheca - is most likely due to a lighter structure for flight, although there were flying birds with teeth, and dinosaurs with toothless beaks are also not uncommon. The color of the beak also often carries information about the physiological status of the individual. The skull of birds, like reptiles, has an unpaired condyle connected to the first cervical vertebra. The braincase is located behind the eye sockets, separated only by a thin bony septum. The premaxillary and dentary bones of the right and left sides are fused (that is, these bones are unpaired). Between the nostril and the orbit is the preorbital fenestra. There is one pair of zygomatic arches, these are the lower arches of the two pairs that the ancestors of birds had. The quadrate bone, to which the lower jaw is attached in most vertebrates, is mobile in birds. Leaning forward, it pushes the zygomatic arch, and it raises the upper jaw - either its entirety, or its anterior end. When the quadrate bone deviates backwards, the upper jaw, on the contrary, lowers. This phenomenon is called cranial kineticism. It allows birds to grasp objects more precisely and more deftly manipulate them in their mouths. The lower jaw, like that of most vertebrates, consists not only of the dentary bone, but also of some others (articulate, angular, and others).
The first two cervical vertebrae, like those of animals, are the atlas and epistropheus adapted to mutual rotation. Ribs in epistrophe. cervical spine are reduced and fused with the vertebral bodies. The articular surfaces of the cervical vertebral bodies are saddle-shaped. The trunk vertebrae of birds are inactive. The pectoral vertebrae in some cases (chicken-shaped, pigeon-shaped, falcon) are fused into the thoracic (chicken-shaped, bone. The lumbar vertebrae are fused with the sacral and first caudal vertebrae into a complex sacrum, which allows them to withstand heavy landing loads, but it began to form even in dinosaurs in connection with running and jumping on the hind limbs. The complex sacrum is followed by several movable caudal vertebrae, the articular surface of the bodies of which is flat. The last caudal vertebrae are fused into a pygostyle, to which the tail feathers are attached. When the tail feathers are reduced, the pygostyle and pygostyle are also absent. Several first and sometimes last ribs do not reach the sternum, so officially the vertebrae to which they are attached should not be considered thoracic. The vertebral part of the ribs usually bears uncinate processes that improve the attachment of the intercostal muscles. The sternal part is always bony. The sternum in birds is large, not segmented, and in adults always ossifies.In a typical case, it bears a keel, to which powerful pectoral muscles are attached. Many flightless birds lack a keel. The shoulder girdle is represented by the coracoid, scapula and clavicle, with the right and left clavicles usually fused into a fork. The coracoid is connected to the sternum by a joint, and in the area of the shoulder joint it is connected to the scapula by cartilage, and to the clavicle by a ligament. Elements of the shoulder girdle can grow together both in flightless birds and, conversely, in well-flying birds. The skeleton of the free forelimb has undergone few changes compared to dinosaurs. But the metacarpal bones fused with each other and with the distal (second) row of carpal bones, forming a buckle. Birds have three wing fingers. The first and third have one phalanx, the second has two. The pelvic girdle consists of the ilium, ischium and pubis, common to land vertebrates. The ilia are very large and extend both anteriorly and posteriorly from the glenoid cavity (as in dinosaurs). They are usually attached to the complex sacrum. The pubic bones usually do not fuse along the midline, so the pelvis of birds is open, which allows them to lay large eggs (the exception is the ostrich, whose 1.5-kilogram eggs are very small compared to itself). The socket of the pelvis is perforated, since the birds' hips are located in a vertical plane, and there is no need to resist the inward force. Due to the vertical position of the thigh, it has, like in animals, a head bent inward, but the pelvis rests not only on the head, but also on the neck of the femur. In the fibula of birds, only the proximal epiphysis remains well developed, which is necessary for attaching the biceps femoris muscle. Then this bone disappears into a thin rod. The proximal (first) row of tarsal bones fuses with the tibia to form the tibia. The distal (second) row of tarsal bones fuses with the second, third and fourth metatarsal bones, forming the tarsus. The joint between the race bone and the tarsus passes, of course, between two rows of tarsal bones (intratarsal joint). The first metatarsal bone is not included in the tarsus. It joins the tarsus through the cartilage as an independent element. The fifth digit of the hind limb is absent in birds. When adapting to fast land movement, the first one can be reduced, and in a single case (ostrich) the second one too. The first finger of birds consists of two phalanges, the second - of three, the third - of four, and the fourth - of five. In the primitive case, bird legs are adapted for fast terrestrial locomotion and have 4 fingers, 1 of which is directed backwards. It can greatly decrease (Anseriformes, Charadriiformes), or disappear (cassowaries, rheas, triplets). In the ostrich, specialization (Anseriformes, Charadriiformes), leading to running led to the loss of not only the 1st, but also the 2nd toe. In the case of arboreal adaptations, the 1st and 4th fingers (cuckoos, parrots, owls, woodpeckers) or the 1st and 2nd (trogons) can be directed backwards. The feet of swifts are adapted to clinging to bumps rather than grasping (trogons). branches, have 4 short fingers pointing forward. The muscles of birds are well developed on the limbs, in the neck and tail sections of the body. The axial muscles of the thoracic and lumbar regions are reduced as unnecessary. The pectoral muscle, the depressor humerus, is the most powerful muscle in flying birds. The function of the supracoracoid muscle is unique to birds - unlike this muscle in dinosaurs, it pulls the humerus up, not down.
The digestive system of birds has little in common with the digestive system of animals. Birds, with rare exceptions such as parrots that are capable of greatly grinding solid food, do not process food or hardly process it in the oral cavity. All modern birds have lost their teeth and are replaced by rhamphotheca, the horny covering of the jaws. There is no secondary palate, since birds do not face the need to combine breathing with chewing or sucking. The proper muscles of the tongue are not developed, and the mobility of the tongue is determined by the mobility of the hyoid bone. Most often, the tongue corresponds in size and shape to the oral cavity, but can be greatly reduced. The salivary glands in birds are only parietal and secrete little or no saliva. Only swifts are capable of secreting a lot of saliva with a high protein content, as they use it when building a nest. Some birds have a crop, an enlargement of the esophagus to store food. Birds that are capable of using abundant but unpredictable food sources (predators or granivores, among our birds these are falconiformes, galliformes, falconiformes, and pigeon-like birds) have a goiter. In granivorous birds, the crop also serves to soak dry food. The stomach in birds consists of glandular and muscular sections. The muscle compartment is lined from the inside with a keratin-like cuticle. Birds that consume roughage have powerful muscles and a thick cuticle of the muscular stomach. They swallow pebbles - gastroliths, which replace their teeth. For animals that fly, or generally quickly change the direction of movement, it is very advantageous to have gastroliths, a heavy chewing organ, located close to the center of gravity of the body. In carnivorous birds, the walls of the muscular stomach are thin, and in the absence of a goiter, they are also highly extensible (cormorants, gulls, owls). The small intestine of birds, like mammals, consists of the duodenum, into which the ducts of the liver and pancreas, jejunum and ileum open. The jejunum, like that of mammals, is the longest. The large intestine is represented by the cecum and colon. The homolog of the rectum is part of the cloaca in birds and is called the coprodeum. Caecum, coprodeum. of which there are two, are well developed in birds that eat rough plant food. They contain symbiotic bacteria that decompose the cellulose of the feed. In carnivorous birds, cecums may be absent altogether. Like mammals, birds have pelvic (metanephric) kidneys, which originate in embryogenesis. However, in birds they are (metanephric), pelvic and in location - located in the recesses of the ilium and complex sacrum. The final product of nitrogen metabolism in birds is uric acid, which is almost insoluble in water and does not require large amounts of water for its excretion. Thus, birds lose almost no water when urinating. The bladder is lost, apparently due to the lightening of the body for flight. The ureters open into the urodeum, the middle section of the cloaca. The orbital gland (located in the eye socket and having a duct into the nasal cavity) is used to excrete salts; it is well developed in seabirds that have to drink salt water. The female reproductive system is characterized by the presence of only one left ovary (most often) and an oviduct (always). The oviduct has a funnel, a long albumen, an isthmus, a uterus and a vagina, and opens into the urodeum of the cloaca. In the funnel, fertilization of a huge, yolk-rich egg occurs, which we usually call the yolk. In the albumen section it is covered with layers of protein, in the isthmus with subshell films, in the uterus (where it spends most of its time in the oviduct) with a shell, and in the vagina with a waxy cuticle. Mating as such is not necessary for ovulation, and in many species the presence of a male is not necessary for oviposition. Apparently, due to the relatively large size of the eggs, birds do not lay a whole clutch of eggs at once, as reptiles do. Birds lay one egg every day or every other day until they have the required number of eggs. Probably, it is precisely with the need to control this required quantity, characteristic of a given species, that birds are inherent in the ability to count. Most birds can lay many more eggs than are contained in a normal clutch if the eggs are taken from them as they are laid. This is the basis for the principle of using egg hens.
In most birds, the ability to fly is achieved when the body size is close to its final size. The exception is galliformes, in which very small chicks are already capable of flitting. The timing of the cessation of contact between chicks and their galliform parents varies. No one cares about the chicks of weed chickens from the moment of hatching; in most species, the connection between young and adults disappears during a given nesting season, but in geese and cranes it persists until the next season. Large birds nest once a year and not even every year; Many small passerines make 2 and 3 clutches per season, and pigeons, which have only 2 eggs in a clutch, make up to 5 clutches. All birds, unlike all other vertebrates, reach sexual maturity significantly later than their final body size. Birds grow very quickly. Small species grow completely in a month, ostrich - in a year. Against this background, the life expectancy of birds seems very long. Even small birds can live 10–15 years. The life expectancy of large birds of prey, large parrots and ravens is approaching 100 years. The respiratory system of birds is very original and has lungs from through parabronchi, in contrast to the lungs of mammals from blind parabronchi ending in alveoli. An analogue, but not a homologue, of the alveoli in birds can be considered air sacs into which air passes through the lungs. After leaving the air sacs, the air passes through the lungs again. In the bags themselves, gas exchange does not occur, but in the lungs it occurs twice - on inhalation and exhalation. Efficient gas exchange allows birds to have the highest metabolic rate among animals. The completeness of oxygen extraction from the air with this method of breathing is such that geese are able to reach a height of 9 km, where the breathing of mammals is generally impossible, and the loon was found alive after 30 minutes. after being caught in a net underwater (the latter, however, would have been impossible without significant reserves of oxygen in the blood and muscles). In addition to breathing, air sacs perform several other functions. Penetrating between the internal organs, they help cool the body, which is very important given the high metabolic rate of birds and the multiple increase in heat production during flight (and the volume of inhaled and exhaled air, of course, increases in the same way as heat production, since both indicators are related to the level of oxygen consumption ). When the air temperature is higher than body temperature, cooling occurs due to the evaporation of water from the surface of the respiratory system. By changing the volume of the air sacs, diving birds regulate their buoyancy. By giving branches into the bone cavity, air sacs reduce body weight. Finally, regulating the volume of the air sacs promotes the emptying of the cloaca, and some of them serve as resonators that increase the volume of vocalizations. The vocal apparatus of birds is represented by the lower larynx, located at the bifurcation of the main bronchi (unlike the upper larynx of mammals). Speaking about these features of the respiratory system of birds, we should not forget that this is only the highest embodiment of the tendency inherent in reptiles. Through lungs are formed to one degree or another in many of them, in contrast to the blindly ending lungs of mammals. Airborne bones are known from dinosaurs and pterosaurs, which also apparently had a very intense metabolism. The circulatory system of birds is characterized by nuclear, as in most vertebrates, red blood cells and a 4-chambered heart with completely separated arterial and venous blood flows. There is only one aortic arch - the right one. The separation of arterial and venous blood is necessary to intensify metabolism. According to the latest findings, dinosaurs most likely also had a 4-chambered heart and one aortic arch. The nervous system is perhaps the only system in which birds are less "high-tech" than mammals. Birds are characterized by a huge number of innate behavioral acts for all occasions, but the ability to learn plays a lesser role in the life of most birds than in mammals. (The exceptions are, perhaps, parrots and passerines). Center passerine). rational activity is localized in birds in the striatum, and not in the cerebral cortex. Unlike mammals, the optic lobes are very large, and processing of visual information occurs in them, and not in the cerebral cortex. The large cerebellum corresponds to the high mobility and complexity of movements of birds.
The leading analyzer in most birds is vision, the importance of which is weakened only in kiwi. Hearing is well developed in all birds, but is most important for owls. The sense of smell is significantly developed in kiwis, American vultures and petrels. Touch, compared to petrels. with mammals, is of negligible importance (with the exception of kiwi). The role of taste is also small, especially in species that swallow food objects whole. Birds' eyes are very large, accommodation occurs by changing the curvature of the lens, changing the distance between the lens and the cornea, and changing the curvature of the cornea. There are usually several “yellow spots”. The field of view is large; The field of binocular vision is significant only in owls, diurnal raptors, herons and swallows. Both eyes in birds are capable of moving independently, but at small angles, while in owls the eyes are completely motionless. Experimental data indicate that the photosensitivity of the eyes of most birds is shifted to the ultraviolet part of the spectrum compared to humans. Diurnal predators have a visual resolution 8 times higher than humans, and owls see in light levels hundreds of times less than humans (and this is one of the most vigilant mammals). The hearing organs of birds are characterized by the presence of one ear bone, the stapes, like in reptiles, and the weak development of the outer ear. Only in owls does the cutaneous pinna receive a degree of development comparable to that in mammals; moreover, in them it is functionally supplemented by a special structure of feathers - the facial disc. The error in passive location of a sound source in owls does not exceed 2°, which is probably facilitated by the asymmetry of the ear openings inherent in some of their species. The specialized organs of touch in birds are vibrissa-like feathers, usually located near the mouth and especially well developed in kiwis and owls. The beak (especially in waders and ibis) and the supporting surface of the legs are rich in tactile nerve endings. Bird communication is also based mainly on the use of vision and hearing. This purpose is served by specific poses and maneuvers, special colors, singing, alarm cries, etc. All these features of birds have long attracted the attention of people, since, in contrast to the primary concept for mammals of the prevalence of olfactory means of communication, in the life of higher primates vision and hearing perform the same functions as in birds. The decisive role of vision is also due to the fact that most birds are diurnal animals. According to the degree of development of social connections, there are birds that unite in pairs only during breeding, and the rest of the time they live alone (hawks); uniting for reproduction in territorial pairs, but migrating and wintering in flocks without maintaining a connection between members of the pair (blackbirds); constantly keeping in pairs (crows, most owls); forming flocks without personal (crows, identification and hierarchical structure (starlings); forming flocks, the members of which recognize each other and have a stable hierarchy; these flocks consist of long-existing pairs, their descendants and newly arrived young animals (crows, pigeons). (ravens, Based on connections with the territory, birds can be divided into sedentary, individual individuals of which both nest and winter within the same territory; migratory, in which the nesting and wintering areas of the species generally do not overlap; and nomadic, individual individuals of which can be were encountered at a specific point in time within partially overlapping breeding and wintering territories. With regard to nomadic birds, it often happens that individuals born in place Y winter in place X, and birds born in place Z winter in place Y, so that each individual the individual is migratory. In nomadic species, young animals always have the greatest mobility, while adults, as a rule, are sedentary (crows, puffy birds, goshawks). The ability to fly allows birds to migrate thousands (crows, kilometers. Methods of orienting birds in space have not been sufficiently studied, but the available data indicate that at long distances birds use innate reactions to the direction of the Earth’s magnetic field lines and to the position of celestial bodies, and at short distances they use learned visual and odor cues of familiar terrain. Among migrating birds, there are those that move gradually and those that make long-distance non-stop flights. The latter accumulate large reserves of fat before migration.
Tests
701-01. Ambient temperature significantly affects body temperature
A) shrimp
B) sparrow
B) dolphin
D) penguin
Answer
701-02. The terrarium with the turtle was taken out into a cool room. As a result, her metabolism
A) became more intense
B) decreased
B) remained unchanged
D) stopped
Answer
701-03. Mammals inhabited areas inaccessible to reptiles, as they are characterized by
A) unstable body temperature and dry skin without glands
B) the presence of digestive, circulatory and other organ systems
B) warm-blooded and high metabolic rate
D) internal skeleton and central nervous system in the form of a tube
Answer
701-04. In which group of animals does the body temperature depend on the ambient temperature?
A) marsupial mammals
B) placental mammals
B) reptiles
D) birds
Answer
701-05. The ability to maintain a constant body temperature was formed in the process of evolution in
A) cartilaginous and bony fish
B) amphibians and reptiles
B) birds and mammals
D) insects and cephalopods
Answer
701-06. The most important feature that distinguishes birds from reptiles is
A) closed circulatory system
B) warm-blooded
B) pulmonary breathing
D) development on land
Answer
701-07. How are mammals and birds similar?
A) outer covering of the body
B) warm-blooded
B) the presence of a bladder
D) reproduction
Answer
701-07. Which of the following animals are warm-blooded?
A) crocodile
B) sheep
B) butterfly
D) frog
Answer
701-08. Which of the following groups of animals are warm-blooded?
A) Bony fish
B) Amphibians
B) Reptiles
D) Birds
Answer
701-09. Mammals and birds eat more than other vertebrates because they
A) larger in size
B) spend energy on thermoregulation
C) store nutrients for the winter
D) more fertile
Answer
701-10. As the ambient temperature increases, the metabolic rate of freshwater fish
A) increases
B) varies depending on their size
B) decreases
D) does not change
Nadezhda Permyakova
Summary of the lesson “Similarities and differences in the structure of mammals and birds” for pupils of the 1st stage of the VIII type school
Target: Establishment resemblance to animals, birds and highlighting the main differences.
Tasks:
Teach students to establish cause-and-effect relationships by finding similarities and differences between birds and animals.
Correction and development of HMF based on exercises in comparison, comparison, generalization.
Cultivating interest in the activity through cognitive activity.
Equipment:
Progress of the lesson
Educator. Good evening, guys! I am very glad to meet you again. Look what I have in my hands?
Children. This is a ball.
Educator. That's right - it's a ball, but not a simple ball, but a ball of luck. He will help us today to unravel all the tasks that our guests have prepared for us. And who are these guests you will find out by guessing puzzles: (after the answer a slide appears)
Large upper lip
He has huge horns on him,
Nature is dear to him.
There was no larger animal in the forest
Since he is eagled, it means -
Children. Elk.
Educator. Though bird, but can’t fly,
Nobody will help her with this.
There's no point in feeling sorry for her -
She is worth two flying.
They sympathize with him in vain -
He always runs great
Making a forced march through the desert.
And out of fear, he hides his head in the sand.
Children. Ostrich.
Educator. Well, here he is rhyme:
Under the beak is a leather bag.
And I'll tell you without a smile
A lot of fish fit in there...
He dives so deep
Which catches a lot and easily.
A handsome, strong giant.
Who is this bird?
Children. Pelican
Educator. Black and white stripes, coloring - excellent.
It's small, but it's a very cute horse.
If you happen to meet her in the city,
At a pedestrian crossing, you may not notice.
Children. This is a zebra.
Educator. The ball whispers to me that all the guests need to be divided according to their method of transportation.
Children divide animals into 2 groups: flying and non-flying, find out that flying is birds, and flightless ones are animals.
Educator. Guys, can you tell us what our guests have in common?
Children. These are animals, they all take care of their own housing and get their own food.
Educator. That's right, guys, only the ball says that they still have more differences. Let's find these differences. Guys, let's look at this one bird. This is a pelican; pelicans do not live here. The pelican has long captured the imagination of impressionable people. He left his mark in legends, mythology and religion. Among the Mohammedans, the pelican is sacred bird. For Christians, it is a symbol of selfless maternal love.
Pelican in ordinary zoology is aquatic bird with a wingspan of about six feet and a very long beak, the lower part of which is widened and forms a pouch for storing fish, but although some of you have not seen this bird, you can tell a lot about her. And the ball will help you with this. He has prepared a plan for you to tell the story about the pelican.
What parts does a pelican's body consist of?
What's on your head?
Why does a pelican have a beak?
What limbs does a pelican have?
What is a tail?
What is the body covered with?
Children. The body of a pelican consists of a head, body, and tail. There are eyes and ears on the head, but they are not visible because of the feathers. There are no external ears. The pelican uses its beak to obtain food for itself. The pelican has wings and legs. The pelican flies with the help of its large wings. Legs birds are thin, the upper part is covered with feathers; the lower part is covered with scales. The feet have four long and thin toes. The fingers have long, sharp, curved claws. When walking, they are widely spaced apart, so the bird stands steadily. The tail is rounded and short. The body is covered with feathers of different lengths. The shortest are on the head, then they become longer and longer, and the longest are on the wings and tail.
Educator. The feathers are directed from front to back and overlap each other. When flying, the feathers do not bristle and do not interfere with movement. In addition, during flight, heat is not blown out from under the feathers. When landing on the ground, the pelican makes a small circle and puts its legs forward, while spreading its tail like a fan. Such an expanded tail, firstly, serves as a brake, reduces speed, and secondly, helps to plan and make a soft landing, otherwise in case of loss of speed bird would fall to the ground very sharply.
Fizminutka "Imitation"- children depict a given animal, its habits, etc.
Educator. Have you rested? Tangle has prepared a new task for us. Tell us about an animal that lives in our forests according to plan.
1. Structure, appearance.
2. Nutrition.
3. Habitat.
Children talk about familiar animals according to plan.
Educator. Well done. You've made some good stories about animals, now let's find differences between birds and animals. This is the last, most difficult task of the glomerulus.
Children. Birds can fly.
Body birds covered with feathers. The body of the animals is covered with fur. U birds have a beak.
Educator. Well done. Concept "animals" more voluminous than a concept « birds» , and the number of species birds much less than the total number of animal species.
Birds are able to fly with the help of wings, unlike animals. Forelegs birds transformed into wings. Skeleton birds has a number of unique adaptations that provide the ability to fly. Only at birds have feathers and beak. Basic life systems operate birds in accelerated mode.
Educator. Ours has come to an end class A little bit of luck helped us cope with all the tasks. Tell me, what was new and interesting for you today?
Children share their impressions.
| № | FEATURES | BIRDS CLASS (Aves) Swans, vultures, bustards, pelicans, penguins | CLASS MAMMALS (Mammalia) Squirrel, giraffe, jerboa, savannah elephant, blue whale, shrew. |
| Number of species | 9 000 | 4 500 | |
| Body measurements | From 2.8 cm (bumblebee hummingbird) to a height of 2.8 m and a weight of 150 kg (African ostrich) | From 3.5 cm, 1.5 g (pygmy shrew) to 33.3 m, 165 t (blue whale) | |
| Cover thickness | Skin is thin | The skin is thick | |
| Glands | Absent (coccygeal gland present) | There are sweat, sebaceous, odorous and mammary glands | |
| Epidermal derivatives | Body covered with feathers | Body covered with hair | |
| Features of the skeleton structure | Lightness and strength, bone growth (for example, in the skull) | Skull with large brain volume | |
| Beak | Eat | Absent | |
| Cervical vertebrae | Quantity varies, extremely mobile | Quantity is usually 7 | |
| Vertebral growth | Observed (complex sacrum) | Absent | |
| Keel | Eat | Absent | |
| Diaphragm | Absent | Eat | |
| Lips | None | Eat | |
| Teeth | None | Differentiated | |
| Oral cavity | There is no mechanical processing of food | Mechanical processing of food occurs | |
| Rectum | Absent | Eat | |
| Airways | Nostrils, nasal cavity, upper larynx, trachea with vocal apparatus in the lower larynx, bronchi | Nostrils, nasal cavity, larynx with vocal cords, trachea, bronchi | |
| Lungs | Relatively smaller, fused with the inner walls of the chest | Relatively large, do not fuse with the inner walls of the chest, but are covered with pleura | |
| Parabronchi | Eat | None | |
| Air bags | Eat | None | |
| Breathing type | Double | Ordinary | |
| Total blood volume | Up to 9% body weight | Up to 9.5% body weight | |
| Red blood cells | They have a nucleus, blood content is 3,500,000 million/mm | Nuclear-free, blood content is about 8.5 million/mm3 | |
| Blood oxygen capacity | Up to 22% | Up to 24% | |
| Aortic arches | There is a right aortic arch, the left one is reduced | There is a left aortic arch, the right aortic arch is reduced | |
| Body temperature | 40-42 °C | 32-38 °C | |
| Cloaca | Eat | Absent | |
| Urinary tract | Absent | Eat | |
| Bladder | Absent | Eat | |
| End product of protein metabolism | Insoluble uric acid | Urea | |
| Accommodation | By moving the lens and changing its curvature | By changing the curvature of the lens | |
| Ears | Absent | Eat | |
| Auditory ossicles | Stapes | Hammer, anvil, stapes | |
| spiral organ | Absent | Eat | |
| Female reproductive system | Asymmetric (there is only the left ovary and left oviduct) | Symmetrical (paired ovaries and oviducts) | |
| Development of the embryo | Outside the mother's body (lay eggs) | In the body, in the uterus, where the placenta forms | |
| Live birth | Absent | Characteristic | |
| Feeding children with milk | Absent | Observed |
Describe livestock farming and indicate its main branches.
Livestock- the second most important (after crop production) sector of Russian agriculture. The well-being of the country as a whole largely depends on how well it is developed. Until recently, livestock farming in Russia was considered unprofitable. Today, thanks to the introduction of new technologies into production, the situation has changed significantly for the better. Livestock farming is divided into several important branches and types.
Branches There are many agricultural breeds. Almost each of them has its own livestock sector. The most significant in our country are: Pig farming. The main products of this livestock industry are meat and lard. Horse breeding. Both breeding of horses, as well as productive and sports breeding, are of great importance for the national economy. Cattle breeding. Cattle breeding is currently the main branch of livestock farming. After all, the degree to which the population will be provided with basic food products, such as milk and meat, depends on how developed this area is. Raising small livestock is also very important. Such areas of the national economy as food (meat, milk) and light (woolen clothing and household items) industries are directly dependent on this area of animal husbandry. Poultry farming. This industry is responsible for providing the population with such important food products as eggs, meat, down and feathers. Fur farming. Breeding nutria, minks, arctic foxes, etc. makes it possible to obtain skins for sewing outerwear, hats, accessories, and other things. Beekeeping. Honey, wax, royal jelly are also more than necessary products. These are the main livestock sectors. In addition to them, our country also has developed reindeer husbandry, fish farming, and camel breeding.
37.When studying the Earth
and its individual parts, geoimages are used - spatiotemporal models of the earth's surface. The need to determine the location of objects on Earth gave rise to the drawing up of maps and plans, the appearance of globes with their special, symbolic language, and the production of aerial photographs and space images. A variety of geoimages allow you to look at the earth's surface from above and imagine the relative position of natural and man-made objects.
A three-dimensional cartographic model of the Earth is a globe, which helps to visualize the position of the planet in space. The first globe was made by the Flemish cartographer Gerardus Mercator in 1490. A geographic globe (from the Latin globe - ball) is a reduced model of the Earth, reflecting its spherical shape. The advantages of the globe are clarity, lack of distortion of the cartographic image, and the ability to demonstrate the axial rotation of the Earth.
1. Similarities and differences between a plan and a geographical map. First, let’s find out the similarity between a local plan and a geographic map. It is known that both a plan and a map are a reduced schematic representation of the Earth’s surface on paper (a plane).
On them, objects of the earth's surface are reduced in scale. Instead of their specific forms, conventional signs are used. Along with such general similarities, there are noticeable differences between a plan and a geographical map. The main ones are the following:
1) scale difference. The plan is drawn on a large scale: 1 cm-5 m, 1 cm-10 m, etc. Due to the large scale, objects on the earth's surface are shown in great detail on the plan. On it you can distinguish individual blocks of the settlement, houses, schools, mosques, palaces of culture, etc. You can draw a plan of the school yard and even a plan of your room if you like.
A geographical map covers large territories - a region, a state, a continent, even the entire globe. Therefore, it is drawn on a small scale. On it, the Earth's surface is reduced by several million times. In terms of completeness and accuracy of the image, only topographic maps are close to plans;
2) regardless of the size of the territory covered Meridians and parallels must be shown on the map(remember how they look in various maps). Meridians show the direction north-south, parallels - west-east. There are no such lines on the plan. The upper part of the plan corresponds to the north, the lower to the south, the left to the west, and the right to the east;
3) the plan covers small areas of land. Therefore, it does not take into account the convexity of the globe and assumes that the earth is flat. Measurement work can be carried out on any part of the plan. The map covers large areas or even the entire globe, Therefore, the spherical shape of the Earth is taken into account here. And depending on the size of the depicted territory, the degree of distortion of the map increases (remember the distortions on the world map and the map of the hemispheres);
4) difference in symbols. If on a plan it is possible to determine the exact dimensions of many objects using conventional signs (the length of a road and river, the area of a lake or garden, etc.), then this is impossible on a map. For example, on a plan it is easy to determine the shape of a settlement, the direction of streets, etc. The map only marks their location.
The soil
This is a special natural body formed on the surface of the Earth as a result of the interaction of living (organic) and dead (inorganic) nature. The most important property of soil, which distinguishes it from rocks, is fertility. It is caused by the presence of organic matter, humus, or humus, in soils.
Main soil types in Russia:
1. Tundra gley soils are found on plains. They are formed without much influence from vegetation. These soils are found in areas where there is permafrost (in the Northern Hemisphere). Often, gley soils are places where deer live and feed in summer and winter. An example of tundra soils in Russia is Chukotka. In areas with such soils, people engage in farming. Potatoes, vegetables and various herbs grow on such land.
2. Arctic soils are obtained as a result of thawing of permafrost. This soil is quite thin. The maximum layer of humus (fertile layer) is 1-2 cm. This type of soil has a low acidic environment. This soil cannot be restored due to the harsh climate. These soils are common in Russia only in the Arctic (on a number of islands in the Arctic Ocean). Due to the harsh climate and small layer of humus, nothing grows on such soils.
3.Podzolic soils are common in forests. There is only 1-4% humus in the soil. Podzolic soils are obtained through the process of podzol formation. A reaction occurs with the acid. That is why this type of soil is also called acidic. In Russia, podzolic soils are common in Siberia and the Far East.
Soddy-podzolic soils are a subtype of podzolic soils. In composition they are largely similar to podzolic soils. A characteristic feature of these soils is that they can be washed out more slowly by water, unlike podzolic soils. Soddy-podzolic soils are found mainly in the taiga (the territory of Siberia). This soil contains up to 10% fertile layer on the surface, and at depth the layer sharply decreases to 0.5%.
Permafrost-taiga soils were formed in forests under permafrost conditions. They are found only in continental climates. The greatest depths of these soils do not exceed 1 meter. This is caused by the proximity to the surface of permafrost. The humus content is only 3-10%.
4. Gray forest soils are formed in forest areas. A prerequisite for the formation of such soils is the presence of a continental climate. Deciduous forest and herbaceous vegetation. The places of formation contain an element necessary for such soil - calcium. Thanks to this element, water does not penetrate deep into the soil and does not erode them. These soils are gray in color. The humus content in gray forest soils is 2-8 percent, that is, the soil fertility is average.
Light gray
Dark gray. (These soils predominate in Russia in the territory from Transbaikalia to the Carpathian Mountains. Fruit and grain crops are grown on the soils
5.Brown forest soils are common in forests: mixed, coniferous and broad-leaved. These soils are found only in warm temperate climates. The soil color is brown. Typically brown soils look like this: on the surface of the ground there is a layer of fallen leaves, about 5 cm high. Next comes the fertile layer, which is 20 and sometimes 30 cm. Even lower is a layer of clay of 15-40 cm. There are several subtypes of brown soils. Subtypes vary depending on temperatures. There are: typical, podzolized, gley (superficial gley and pseudopodzolic). On the territory of the Russian Federation, soils are distributed in the Far East and in the foothills of the Caucasus. Low-maintenance crops such as tea, grapes and tobacco are grown on these soils. Forests grow well on such soils.
6. Chestnut soils are common in steppes and semi-deserts. The fertile layer of such soils is 1.5-4.5%. Which indicates average soil fertility. This soil has chestnut, light chestnut and dark chestnut colors. Accordingly, there are three subtypes of chestnut soil, differing in color.
In light chestnut soils, farming is possible only with abundant watering. The main purpose of this land is pasture.
The following crops grow well in dark chestnut soils without watering: wheat, barley, oats, sunflower, millet.