"Class Mammals. Detachment Primates". Primates - interesting facts about the order of animals related to humans Distinctive features of the order of primates

Many people have a special interest in the order of mammals known as primates, for the simple reason that Homo sapiens are themselves directly related to primates. In this article, you'll discover 10 interesting facts about primates, a widespread animal group that includes monkeys, lemurs, tarsiers, and humans.

1. The word primates means "the first"

Perhaps in this name lies human egocentrism. Primates in Latin means "first", not a very subtle reminder that man considers himself the pinnacle of evolution. WITH scientific point In view, there is no reason to believe that monkeys, tarsiers and lemurs, representing a detachment of primates, are more advanced in terms of evolution than birds, reptiles and even fish. They just took a different evolutionary path millions of years ago.

2. There are two main suborders of primates

Until recently, naturalists divided the squad into half-monkeys. (prosimii) and humanoid primates (Anthropoidea). Today, the classification of primates has undergone significant changes. Now the squad is divided into the following two sub-orders:

• wet-nosed (Strepsirhini), which includes lemurs and loris;
• dry-nosed (Haplorrhini), dividing into tarsiformes and apes.

We humans belong to the suborder of the dry-nosed.

3 Primates Have Bigger Brains Than Other Mammals

There are many anatomical characteristics that distinguish primates from other orders of mammals, but the most main feature is their brain. Monkeys and other members of the order have a larger brain relative to body size than other animals. Why do primates need big brains? To process the information necessary for effective use(depending on species) their opposable thumb, prehensile tail, and keen binocular vision.

4 The First Primates Evolved At The End Of The Mesozoic Era

Fossil evidence is still disputed, but most paleontologists agree that the first primates appeared between the middle and the end Cretaceous. Early candidates for the role of the first primate include the North American purgatorius, and then, ten million years later, the plesiadapis appeared, living in the open spaces North America and Eurasia. After that, there was an important evolutionary split between prehistoric and modern world primates. It is unclear exactly when this event occurred, but most likely during the Eocene epoch.

5 Primates Are Pretty Social Animals

Perhaps because they rely more on their brains than claws and teeth, most primate species tend to seek protection in communities such as clans, monogamous male-female pairs, and even apparently human-like families. . However, it is important to understand that primate social associations are not oases of calm and comfort. Killings and abuse are depressingly common, and some species even kill newborn babies of their own clan.

6 Primates Can Use Tools

You could write a whole book about "tool use" in the animal kingdom. Suffice it to say that naturalists no longer consider this behavior to be a feature of primates (for example, some birds use branches to pull insects out of trees). However, primates use far more tools than any other order of animals. Sticks, stones and leaves are used for various challenging tasks(for example, to clean the ears or pick out dirt from under the toenails).

Of course, it was Homo sapiens who excelled at using the tools, thanks to which we were able to build a modern civilization!

7 Primates Grow Slower Than Other Mammals

Big brains are kind of a blessing and a curse: they help in reproduction, but also take longer to develop. Newborn primates, with their immature brains, are unable to survive without the help of one or both parents, or social group, over several months or years. Also, like humans, most primates give birth to only one calf, which entails a large investment of parental resources (and sea ​​turtle can afford to ignore her offspring, because only one in twenty hatched turtles will make it to the big water).

8 Most Primates Are Omnivorous

One of the reasons why primates are so widely distributed around the planet is the fact that most species (including great apes and chimpanzees) are omnivores. However, tarsiers are considered the only primates that are exclusively carnivorous, and some species of lemurs, howler monkeys, and marmosets are vegetarians.

9. Primates are sexually dimorphic

This is not a hard and fast rule, but many primate species exhibit sexual dimorphism, a tendency for males to be larger and more dangerous than females. Males of some primate species also have coat colors and large teeth that are distinctive from females. Oddly enough, the manifestation of sexual dimorphism in humans is one of the most subtle among all primates on the planet, males outweigh females by only 15% on average (although you can draw your own conclusion about the aggressiveness of men towards women).

10 Some Primate Species Have Yet To Be Discovered

Of all the orders of mammals on Earth, primates can be assumed to be the best studied: after all, most human naturalists have a special interest in tracking down our closest relatives. But given the tendency of small primates to hide in remote areas of the rain jungle, we are only fooling ourselves if we think we have discovered all the species. As recently as 2001, 350 primate species were identified, today there are about 450, which means that about half a dozen new species are discovered each year.

The initial interest in monkeys, the anatomical description of which we find in Aristotle, led to the development of a separate section of biological science - primatology. This section summarizes data on fossil monkeys, as well as the results of observations of their currently existing species.

Most primates lead an arboreal lifestyle. Their body length varies from 12 cm (some semi-monkeys) to 2 m (gorillas). In the process of adapting to an arboreal existence, the ancestors of primates developed many properties that corresponded to their way of life.

Primates have five-fingered grasping limb. Five-fingeredness, the oldest sign of mammals and terrestrial vertebrates in general, was preserved in primates and contributed to the formation of a grasping limb. This led to increased mobility, variety of movements and tenacity of the limbs. These properties of the forelimb are due to the presence of the collarbone, which all primates possess. The mobility of the forearm is associated with pronation and supination characteristic of primates, i.e. the ability of the radius to rotate freely relative to the ulna, to perform flexion and extension movements in the elbow joint.

Tenacity in most primates is due to the ability of the first finger to oppose the rest. Primate fingers are mostly equipped with flat nails rather than claws. In those forms that have claws on separate fingers, the first is always provided with a nail.

When primates move on the ground, they usually rely on the entire foot. Therefore, they can be defined as plantigrade animals, less adapted to fast running than typical terrestrial forms - digitigrade.

Life on trees gives primates a variety of food - fruits, leaves, berries, buds, as well as insect larvae, chicks, eggs, i.e. - Mixed food. All three categories of teeth are involved in its chewing, and this allowed primates to avoid those unilateral changes in the dental apparatus that characterize other orders of mammals, such as ungulates, rodents, carnivores, etc. Primates, like humans, are characterized by the presence of all types of teeth (incisors, canines, premolars and molars), and the number of these teeth is relatively constant. Such a dental system is called heterodont. Primates are characterized by a complete change of teeth, that is, two generations - dairy and permanent.

A grasping, very mobile hand, frees, to a certain extent, the jaws from the functions of capturing food. Many primates grasp food, usually with their hands, and bring it to their mouths. This relief of the load on the jaw apparatus was reflected to some extent in a decrease in the size of the jaws and, in general, in a decrease in the facial part of the skull compared to the brain part. The process of changing the ratios between the brain skull and the facial one is also associated with other phenomena that took place during the evolution of primates.

The arboreal way of life affected the relative importance of the sense organs of these animals. Primitive land mammal is guided in its behavior mainly by olfactory sensations. The olfactory organ plays the first role in the life of such an animal, and the olfactory lobe of the cerebral hemispheres is the largest and most progressive. With a predominant existence on a tree and with a separation from the ground, the situation changes; on trees, the animal's perception of odors loses its meaning. Hearing and an accurate eye are much more important here. Arboreal animals progressively develop the corresponding sense organs. In addition, for primates with their prehensile limbs, with their easily movable fingers, tactile sensations are of great importance, especially acutely perceived through sensitive bare skin located on the limbs. The ends of the fingers of primates in connection with this are expanded; they are protected by flat nails (instead of the claws of most other mammals) and on their skin, in contact with surrounding objects, there are “tactile patterns” - rows of thin rollers arranged in arcs, loops, circles, ovals.

The increased development of the organ of sight and touch was accompanied by a decline in the role of smell in primates. Accordingly, they have a reduced number of turbinates and the entire nasal region of the skull. This, in turn, reduces the face and changes its relationship to the cerebral skull in favor of the latter. Finally, the rapid development of those areas of the cortex that are involved in the conscious perception of visual and tactile sensations has led to a general increase in the mass of the brain and its deep restructuring. The hemispheres grow so much that other parts of the brain do not keep up with it; the occipital part of the hemispheres in many primates covers the cerebellum (partly or entirely), just as it does in humans. Not only the cerebral hemispheres develop, this process also covers the cerebellum, but the latter does not develop as quickly as the large brain. The total mass of the brain compared with the body mass in primates changes in the direction of cerebralization.

Enlargement and internal restructuring of the brain was a prerequisite for the development of close coordination of various and complex movements performed by primates when climbing, hanging from branches, and jumping through trees. Along with this, primates have developed an instinctive desire to manipulate objects, regardless of their nutritional value. Any unfamiliar thing the monkey grabs, examines, feels from all sides, tries with teeth and tongue, etc. All this is possible only with a relatively high level of development of the psyche and brain.

Therefore, primates are characterized by a greater development of the cerebral hemispheres in comparison with other mammals, an increase in its volume and, in accordance with this, an increase in the capacity of the cranium. Big size of the cranium and brain, its high differentiation is associated with the extraordinary mobility of the representatives of this order and the variety of functions of their forelimbs.

Most primates have lost the seasonality of their sexual life and are able to breed throughout the year. The detachment is characterized by low fertility, most often one cub is born. Decrease in fertility and increased care for offspring created Better conditions for survival. Primates are characterized by an increase in the period before the onset of puberty, at which time experience is transferred from adults to a new generation.

The communication of individuals in the herd occurs with the help of facial expressions and vocalization - both of these methods have reached high development in monkeys. Monkeys can make about 50 different sounds, which serve as signals of danger warning, curiosity, friendly greeting, enthusiasm, displeasure, etc.

The structure of the larynx of monkeys differs significantly from its structure in humans. All attempts to teach them to pronounce words by imitation ended in failure. At the same time, it was possible to teach chimpanzees "sign language" - they mastered about 120 words expressing their needs and requests addressed to the experimenter. It is clear that there is a huge qualitative difference between these methods of transmitting information and human speech based on abstract thinking.

Signs that characterize the detachment of Primates:

1) Limbs of a grasping type, five-fingered, thumb mobile and many can be opposed to the rest. Nails are developed on the fingers.

2) Heterodont dental system.

3) The brain has a larger volume and complex structure, the eyes are directed forward.

4) When walking, they rely on the entire foot.

5) With low fecundity, they are capable of reproduction throughout the year.

The listed features characteristic of primates explain why it was in this order that the progressive direction of evolution became possible, which led to the appearance of man.

Questions and tasks for self-control

I. Give answers to control questions.

1. Give an explanation of direct and indirect evidence confirming the high degree of human relationship with animals and great apes.

2. Describe the systematic position of man in the animal world.

3. In connection with what features of the structure of living primates are divided into two main groups of suborders - Strepsirin and Gaplorin.

4. Describe the appearance of strepsirin primates, which families of semi-monkeys belong to them?

5. Name common features haplorin primates, give a description of the taxa included in this group.

6. Describe the structure, lifestyle and taxonomy of the suborder Tarsiers.

7. Give a description of the structure, lifestyle and taxonomy of broad-nosed monkeys.

8. Narrow-nosed monkeys: structure, lifestyle and taxonomy.

9. Describe the taxonomy of the superfamily Hominoids.

10. List the signs that characterize the detachment of Primates.

II. Choose the correct answer.

1. To direct evidence supporting family ties humans and animals and a high degree of human kinship with great apes include:

And the bones of a fossil man;

B data of comparative embryology;

In physiological data;

The doctrine of rudimentary organs and atavisms;

D all answers are correct.

2. TO vestigial organs of a person who, in his distant ancestors, had functional significance, but gradually lost it in the process of evolution, include:

And the remains of the general hairline;

B tail vertebrae;

In polymastia;

D muscles that move the auricle;

D all answers are correct.

3. According to the criteria of zoological systematics, the species "Homo sapiens" refers to:

And the suborder of the Semi-monkeys;

B suborder Dolgopyatovye;

In the infraorder broad-nosed monkeys;

To the infraorder Narrow-nosed monkeys;

D all answers are correct.

4. The human body has many features in common with mammals:

And all answers are correct;

B four-chambered heart;

In nuclear-free erythrocytes;

G spine;

D constant body temperature.

5. The most ancient group of Strepsirin primates does not include:

And lemurs;

B tarsiers;

In tupai;

6. What primates are characterized by the formation of "mixed flocks", which may even include raccoons and birds?

And the lower narrow-nosed monkeys;

B tarsiers;

In broad-nosed monkeys;

G hominoids;

7. Bonobo belongs to the genus:

And Gorillas;

B Gibbons;

The Orangutans;

G Chimpanzee;

D All answers are wrong.

8. A trait uncharacteristic for the order Primates:

And they are only capable of seasonal reproduction;

B the brain has a larger volume and complex structure;

In walking, they rely on the entire foot;

G grasping limbs;

D gerotodontic dental system.

9. The most evolutionarily successful family of monkeys, all species of which are diurnal.

B Monkeys;

In marmosets;

G Lemurs;

D Orangutans.

10. Primates progressively develop sensory organs that cause the following types of sensitivity:

And the sense of smell;

B taste and touch;

In sight;

D hearing and smell;

Sight, hearing and touch.

The primate order is divided into two suborders and 16 families:

Suborder Wet Nose ( Strepsirrhini) includes the following families:

• Dwarf lemurs ( Cheirogaleidae);
• Lemurs ( Lemuridae);
• Lepilemory ( Lepilemuridae);
• Indriaceae ( Indriidae);
• Hand-legged ( Daubentoniidae);
• Loriaceae ( Loridae);
• Galagic ( Galagonidae).

Suborder Dry-nosed ( Haplorrhini) consists of the following families:

• Tarsiers ( Tarsiidae);
• Igrunkovye ( Callitrichidae);
• chain-tailed monkeys ( Cebidae);
• night monkeys ( aotidae);
• Sakov ( Pitheciidae);
• Spider Monkeys ( Atelidae);
• Monkey ( Cercopithecidae);
• Gibbons ( Hylobatidae);
• hominids ( Hominidae).

Evolution

Fossils of early primates are from the early (56 to 40 million years ago) or possibly the late Paleocene (59 to 56 million years ago). While they are an ancient group, and many (especially the broad-nosed or New World monkeys) have remained fully arboreal, others have become at least partially terrestrial and have achieved a high level of intelligence. There is no doubt that this particular detachment includes some of the.

Lifespan

Although humans are the longest-lived primates, the potential lifespan of chimpanzees is estimated at 60 years, and orangutans sometimes reach that age in captivity. On the other hand, the lifespan of lemurs is about 15 years, while that of monkeys is 25-30 years.

Description

Roxellan rhinopitecus

Despite notable differences between primate families, they share several anatomical and functional characteristics that reflect their common order. Compared to body weight, the primate brain is larger than that of other mammals and has a unique spur-like groove that separates the first and second visual areas on each side of the brain. While all other mammals have claws or hooves on their fingers, primates have flat nails. Some primates have claws, but the thumb still has a flat nail.

Not all primates have equally nimble hands; only narrow-nosed monkeys (marmosets and hominids, including humans), as well as some lemurs and lorises, have an opposable thumb. Primates are not the only animals that grasp various objects with their limbs. But since this characteristic is found in many other arboreal mammals (such as squirrels and opossums), and since most modern primates are arboreal, it is assumed that they evolved from an ancestor that was arboreal.

Primates also have specialized nerve endings on their limbs that increase tactile sensitivity. As far as is known, no other placental mammal has them. Primates have fingerprints, but so do many other arboreal mammals.

Primates have binocular vision, although this feature is by no means limited to primates, but it is a common characteristic seen among . Therefore, it has been proposed that the ancestor of primates was a predator.

Primate teeth differ from those of other mammals by having low, rounded molar and premolar teeth that contrast with the long, sharp teeth of other placental mammals. This difference makes it easy to recognize primate teeth.

Size

Members of the primate order show a range of sizes and adaptive diversity. The smallest primate is the mouse lemur ( Microcebus berthae), which weighs about 35-50 grams; the most massive primate is, of course, the gorilla ( Gorilla), whose weight varies from 140 to 180 kg, which is almost 4000 times the weight of the mouse lemur.

Geographic range and habitat

Primates occupy two main vegetation zones: and. Each of these zones has created appropriate adaptations in primates, but among the arboreal species there may be more variety of bodily forms than among the inhabitants of the savannah. Arboreal primates have many of the same characteristics that likely evolved as adaptations to life in trees. Several species, including our own, have left their trees to become terrestrial.

Non-human primates have a wide distribution throughout tropical latitudes, India, Southeast and . In Ethiopia, gelada (genus Theropithecus) is found at altitudes up to 5000 meters. The gorillas of the Virunga Mountains are known to pass through mountain passes at over 4,200 meters. Red Howlers ( Alouatta seniculus) Venezuelans live at an altitude of 2500 meters in the mountains of the Cordillera de Merida, and in northern Colombia, the Mirikins (genus Aotus) are found in the tropical mountain forests of the Central Cordillera.

The gestation period varies among primate species. For example, mouse lemurs have a gestation period of 54-68 days, lemurs 132-134 days, macaques 146-186 days, gibbons 210 days, chimpanzees 230 days, gorillas 255 days, and humans (on average) 267 days. Even in small primates, the gestation period is significantly longer than in other mammals of equivalent size, reflecting the complexity of primates. Although there is a general evolutionary trend in primates towards an increase in body size, there is no absolute correlation between body size and the length of the gestation period.

The degrees of puberty and maternal dependence at birth appear to be closely related. Newborn primates are not as helpless as kittens, puppies or rats. With few exceptions, the young primate is born with open eyes and fur. Cubs should be able to cling to their mother's fur; only a few species leave their babies in shelters while feeding. Cubs of the most higher primates able to cling to the mother's fur without outside help; however, humans, chimpanzees, and gorillas must support their newborns, and humans do so the longest.

Once the primate infant has learned to support itself by standing on its two (or four) legs, the physical dependency phase is over; the next stage, psychological addiction, lasts much longer. The human child is attached to the mother for a much longer time than the non-human primate. The adolescent period of psychological maternal dependence is 2.5 years in lemurs, 6 years in monkeys, 7-8 years in most hominoid, and 14 years in humans.

Behavior

Primates are among the most social animals, forming pairs or family groups. On social systems three main influences environmental factors: distribution, group size and predation. Within a social group, there is a balance between cooperation and competition. Cooperative behavior includes social grooming, food sharing, and collective defense against predators. Aggressive behavior often signals competition for food, sleeping quarters, or helpers. Aggression is also used to establish dominance hierarchies.

It is known that several species of primates can cooperate in wild nature. For example, in national park Tai, in Africa, several species coordinate behavior to protect themselves from predators. These include Diana monkey, Campbell's monkey, lesser white-nosed monkey, red colobus, king colobus, smoky mangobey. Among the predators of these monkeys is the common chimpanzee.

Primates have developed cognitive abilities: some make tools and use them to obtain food and for social display; others have complex hunting strategies requiring cooperation, influence and dominance; they are status conscious, manipulative and deceitful; these animals can learn to use symbols and understand human language.

Some primates rely on olfactory cues for many aspects of social and reproductive behavior. Specialized glands are used to mark territories with pheromones that are picked up by the vomeronasal organ. Primates also use vocalizations, gestures, and emotions to convey a psychological state. Like humans, chimpanzees can distinguish between familiar and unfamiliar faces.

Primate conservation

While many primates are still abundant in the wild, populations of many species are in sharp decline. According to International Union Conservation Agency (IUCN), more than 70% of primates in Asia and approximately 40% of primates in South America, the African mainland and the island of Madagascar are listed as endangered. A number of species, especially the gorilla, some of Madagascar lemurs and some species from South America, are in serious danger of extinction as their habitats are being destroyed and poaching is rampant.

However, some endangered species have increased in numbers. A concerted captive breeding effort has been successful, and reintroduction into the wild is also practiced in Brazil.

Primates are a group of animals that, for the most part, biological characteristics do not differ from modern human populations, and its evolutionary paths diverged from the paths of man later than all other animals. The shared characteristics of humans and primates serve both as proof of human evolution and as a source of ideas and doubt. Primates provide a context for the study of human evolution. Primates are a class of mammals characterized by the retention of some primitive traits and the progressive development of more specialized traits associated with in a woody way life and a high degree specializations.

Characteristic features of primates

It often happens like this: the description of any group of mammals looks unsuccessful. A formal enumeration of features does not give the reader any idea about the object. However, the most boring description of primates, given in 1873 by the English biologist Jackson Myvart, is also the most reliable: "Placental mammals with claws and clavicle, orbits surrounded by bone, all three types of teeth; pituitary gland with posterior lobe and spur groove; inner finger, along on at least one pair of limbs opposed to the rest; thumb with or without broad nail; caecum well developed; penis hanging down; testicles in scrotum; two mammary mammary glands. And although this description does not capture the true beauty of primates and does not give an idea of ​​\u200b\u200btheir amazing lifestyle, it remains nevertheless the most accurate. Modern scientists can only add two strokes to this portrait: "a shortened nasal part of the muzzle and a flat face provide good spatial and color vision, and a relatively large brain with a developed cerebral cortex determines complex behavior."

This description is very general. There are primates that lack this or that feature. On the other hand, some of the features mentioned are also found in other groups of animals. For example, many mammals have clavicles and three types of teeth.

The order Primates belongs to the class of mammals, the subtype of vertebrates, the type of chordates. The following features are characteristic of the chordate type:

1. The skeleton is formed by a chord - a highly vacuolated connective tissue - which is necessarily present at least at one of the stages of ontogenesis, for example, in embryogenesis;

2. Central nervous system - in the form of a tube with a slit;

3. In front of the digestive tube - the pharynx - there are gill slits;

4. For all chordates, the general plan of the structure of organ systems is typical: the intestine is under the chord, and it is under the neural tube.

In addition, all chordates have features that make them related to invertebrates - this is bilateral symmetry and a secondary mouth. A typical representative of the simplest chordates lancelet. The vertebrate subtype includes the following classes: fish, amphibians, reptiles, birds and mammals. All of them are united by the presence of the jaw apparatus, an active lifestyle, that is, an active search for food and a sexual partner. With active movement, limbs appear: in fish, these are fins, and in other representatives, the limbs of a five-fingered. In connection with orientation, the sense organs, the brain and spinal cord develop, and the skull and spine that protect them appear. All vertebrates have an intensive metabolism, a closed circulatory system, a heart, respiratory and excretory organs.

The class of mammals is characterized by live birth, carrying a cub in the uterus and feeding it with milk. Mammals have a dentition different types teeth, reflecting their food specialization - incisors, canines, premolars and molars. Milk teeth are replaced by permanent ones. All mammals are homoiothermic (this is with a constant body temperature) animals with a high level of metabolism. Their body is covered with hair, which are derivatives of the skin. Females have mammary glands. All mammals, in addition to the inner and middle, also have an outer ear.

The structure of the skeleton of the representatives of the detachment

The four-legged lemurs, as well as most monkeys like monkeys, have retained the original structure of the ancient primates. They have a long back, short and narrow rib cage, long and thin femurs, hind limbs are not shorter than the front ones. These animals live mainly on trees, running or jumping along the branches. The long tail plays the role of a rudder or balancer during jumps. Terrestrial monkeys, such as baboons, usually have much shorter tails.

Great apes and sluggish prosimians do not have tails. In orangutans and other great apes, the back is shorter, the chest is wider, and the pelvic bones are stronger. These are traits associated with an upright posture. The arms are longer than the legs, especially in species such as gibbons and orangutans, which move by swinging their arms (brachiation).

The structure of the arms and legs in primates is associated with their lifestyle (Fig. 1):

1. The hand of a spider monkey with a very short thumb is characteristic of species that move with the help of arm swings. 2. Gibbon: The short, opposed thumb is away from the others involved in the brachiation grip. 3. Gorilla: the thumb on the hand is opposed to the rest, which contributes to the accuracy of manipulation. 4. Macaques: The short, opposed thumb allows the animals to rest on the ground with an open palm. 5. Tamarin: a long foot and claws on all fingers, except for the big one, are characteristic of all species clinging to tree branches (in other monkeys, all fingers are equipped with flat claws). 6 Siamang and 7 Orangutan: wide foot with long, grippy thumb, good for climbing. 8. Baboon: long graceful foot is convenient for moving on the ground.

Rice. 1 Limbs of primates

The jaws of the insectivorous ancestors of primates were armed with numerous pointed teeth (Fig. 2). In strepsirrhines such as lemurs (1), the first lower premolar is shaped like a canine, and the surfaces of the lower incisors and canines lie in the same plane, forming a toothcomb similar to that of the galagos. Galago use this comb during feeding and grooming. In leaf-eating monkeys of the Old World, for example, thin-bodied (2), the surface of the molars is, as it were, divided into squares by four sharp protrusions connected by oblique ridges - it turns out good tool for grinding roughage. In great apes, in particular in the gorilla (3), the lower molars have five protrusions, and the ridges have a complex shape.

Rice. 2. General form teeth different types primates

Anatomical and physiological features of the detachment

Primates are medium-sized mammals. They are larger than insectivores and bats, smaller than most ungulates and cetaceans. Their body weight ranges from 30 g (in the gray mouse lemur) to 150 kg or more (in male gorillas). Like other mammals, large species Primates breed less often, but live longer than their smaller relatives.

Mouse lemurs are able to breed already at the age of one year and every year give birth to 2 cubs weighing 6.5 g after a 2-month pregnancy. The longevity record for a mouse lemur is 15 years. On the contrary, the female gorilla becomes sexually mature only by the age of 10 years. She gives birth to one cub weighing 2.1 kg after 9 months of pregnancy and can become pregnant again only after 4 years. Gorillas usually live up to 40 years.

With significant species differences, a small offspring is common to all species of monkeys: the female gives birth to only one or two cubs at a time.

The growth rate of young animals in primates is also low, much lower than in other mammals with a similar body weight. The reason for this difference is unclear, but may be related to brain size. Brain tissues are the most energy intensive in the body. High level metabolism in the brain in large primates reduces the rate of growth of the body and the development of reproductive organs.

Due to low reproduction rates, primates have a rather strong propensity for infanticide. It is not uncommon for males to kill offspring born by a female to other males, as the lactating female is unable to conceive again. Males, even at the peak of their physical development, are limited in their attempts to reproduce and do everything possible to maintain their genotype. So, the male monkey Hanuman has only 800 days to procreate out of 20 years of life.

Body weight differs not only in different primates, but also in males and females of the same species. Males are usually larger than females (although there are many exceptions to this rule).

In some monkeys, the family consists of one male and several females. Since body weight gives the male an advantage in a duel with his own kind, there is a natural selection for an increase in body weight. The male Hanuman sometimes gathers a harem of 20 females, whom he has to protect from the encroachments of other males. The body weight of the harem owner can be 160% of the female's weight. In contrast, in species whose males usually mate with only one female (gibbons), the sexes do not differ in size. Sexual dimorphism in lemurs is very weakly expressed. These animals live in groups, like other primates. Scientists suggest that the social structure in these animals is different from that of other primates.

Not only the size of the body plays a role in the tough struggle for paternity. Fangs are powerful weapons, which are used by males in fights and aggressive demonstrations. In addition, there are more sophisticated ways to defeat the enemy. There are species in which several males fertilize one female. The winner is the one who has large testicles and is able to produce more sperm. This increases the likelihood of fertilization of the egg by the sperm of the record-breaking male.

Sexual competition is reflected not only in the morphology of males. In many female primates, breeding cycles are accompanied by periodic reddening and swelling of the skin in the anagenital region. Such a pattern, clearly visible from afar, becomes most vivid on the days of ovulation. This phenomenon is typical for species living in large mixed groups. Females with swollen flesh are most attractive to males. Although females tend to mate with stronger and larger males, they attract everyone, even young ones. Ultimately, this reduces the likelihood of infanticide: even a small chance of participating in reproduction prevents males from trying to kill other people's cubs. So important is swollen flesh as a signal of readiness to reproduce that female geladas, whose anagenital region is poorly visible because these monkeys feed while sitting, have evolved patches of skin with the same function on the chest.

Currently, scientific classification does not use the terms "higher" and "lower" monkeys in this context. These are only descriptive terms with no classificatory value. The following classification of the suborder of anthropoid apes (Anthropoidea) is now accepted, which includes 3 superfamilies: the superfamily Broad-nosed monkeys, the superfamily Lower narrow-nosed monkeys and the superfamily Hominoidea. lower primates representatives of the semi-monkey suborder are called, and all monkeys of the Antropoidae suborder, or humanoid higher apes, are called higher monkeys (as, by the way, the author himself does when describing the Tarsier family. The use of these terms (higher and lower) in relation to primates can only lead to even more confusion that already exists in the taxonomy of this order of mammals.

The order contains about 150 species. Monkeys are varied appearance, ecology and other characteristics, but at the same time they have common features of the body structure: five-fingered grasping limbs and developed collarbones; the brushes bend and unbend well; the first fingers of the hands in many species are opposed to the rest; there are nails on the fingers (some semi-monkeys have claws); the orbits are separated from the temporal pits either by the periorbital ring or by a bony septum; eyes are directed forward; four types of teeth (newborns are characterized by the presence of milk teeth, which are then replaced by permanent ones); the caecum is developed; have a placenta, etc.

In terms of body size, primates vary from 8-15 cm in length (tarsier, pygmy marmoset, mouse microcebus) up to 2 m (gorilla). Average weight mouse microcebus - 60 g, while a gorilla can reach a weight of 300 kg. Corresponds to different body sizes and different duration primate life. Some species of monkeys maximum age does not exceed 10 years (various types of marmosets), in others - 57-60 years (orangutan).

For primates (as well as for the vast majority of mammals), live birth is characteristic. After birth, the cub is fed with mother's milk. The length of the gestation period is related to life expectancy. The amplitude of this value in primates is significant: from 40 days in tupai to 270-290 days in great apes.

Like all other mammals, during the period of embryonic development they develop a notochord, gill slits, and a hollow neural tube. In the process of fetal development, the listed formations develop, change or overgrow. The development of the fetus in the womb leads to the formation of the spine, the internal axial skeleton, two pairs of limbs, a closed circulatory system and complex nervous system, as well as a special arrangement of organs (in particular, the heart on the ventral side of the body). Representatives of this order of mammals are covered with hair and have mammary glands; primates have a peculiar structure of the inner ear and teeth.

Monkeys have a perfect system of thermoregulation, due to which the body has a relatively constant temperature, which ensures constancy internal environment organism, regardless of the external Wool retains heat; it is, as a rule, extremely varied in color, but there are species with a natural white coat. Cases of albinism have also been noted, in particular, in the gorilla, capuchin, rhesus monkey, mangabey, colobus, spider monkey, lory. Albino monkeys in natural conditions do not live long, they are expelled from the flock or family and die from predators.

There are species of monkeys with very long tails, significantly exceeding the length of the body, as well as with short tails; there are monkeys with almost imperceptible tails and even tailless ones. Tails can perform a variety of functions: grasping (with the help of a tail, a monkey can cling to a bough or trunk), a rudder function - when jumping from tree to tree or on the ground. With the help of the tail, the monkey can hold the cub sitting on its back, lean on it, etc.