Structural features of representatives of the primate order. Biological features of primates. Origin and immediate family

Section broad-nosed primates (Platyrrhina) Section broad-nosed primates in diagram 3 includes one superfamily Ceboidea with three families of American monkeys and 16 genera. This is almost one third of the genera of the entire order of primates. Monkeys of small and medium size (the size of a dog, for example

Section narrow-nosed primates (Catarrhina) We continue the description great apes. This section includes not only lower monkeys, as in the previous one, but along with one superfamily lower apes(Cercopitliecoidea) - another superfamily of hominoids, or higher apes and humans

Primates There are 194 species in the order of primates: humans, 70 species of monkeys in the tropical forests of the New World, 70 in the Old World, and here there are 53 species of prosimians. Primates evolved from insectivores, retaining some of their features. With every new study, science is convinced that

4. Primates Row 10 gives the EQ of the first primates (0.75), which appeared approximately 60 million years ago after the extinction of the dinosaurs. The EQ value of the first primates was approximately the same as that of the average mammals and birds that lived at that time. In lines 11 to 15

Order Insectivores This order includes hedgehogs, moles, and shrews. These are small animals with a small brain, the hemispheres of which do not have grooves or convolutions. The teeth are poorly differentiated. Most insectivores have an elongated muzzle with a small proboscis.

Order Lagomorpha These are small and medium-sized mammals. They have two pairs of incisors in the upper jaw, located one after the other so that behind the large front ones there is a second pair of small and short ones. IN lower jaw only one pair of incisors. There are no fangs, and incisors

Order Primates This order includes the most diverse mammals in appearance and lifestyle. However, they have a number of common characteristics: a relatively large skull, the eye sockets are almost always directed forward, the thumb is opposed

Sexual dimorphism and the leading type of sexual relations: modern primates and fossil hominins Still certain connections between the type sexual relations in monkeys, a number of morphophysiological parameters exist for male and female individuals. In particular,

Sperm wars: primates and humans We have already said above that competition between males can take place not only through tournaments, defending territory, or stealing females from a weaker (or older) enemy. Competition can take things hidden from view

Everyone has heard about the comparison of man with monkeys or the scientific assertion of his origin from these animals. Which is not surprising, since humans are one of the representatives of the Primate order, which includes many other mammals.

Representatives of the order Primates are smart animals with good reactions. They have unique features that other animals do not have. Below you will find articles about representatives of the Primates order, in which you can discover a lot of new and incredible things about these funny animals.

The common capuchin is a friendly monkey. Description and photo of the common capuchin

The common capuchin is a representative of the family of prehensile-tailed monkeys from the order Primates. A noisy and active creature. The common capuchin is also called the Steller's capuchin. This species of primate is one of the friendliest. In this article you will find a description and photo of the common capuchin and learn a lot of interesting things about this charming monkey.

The ring-tailed lemur is a restless lemur from Madagascar. Description and photo of the ring-tailed lemur

The ring-tailed lemur (other names ring-tailed lemur, catta lemur) is the most popular species of the lemur family. The ring-tailed lemur is a member of the order Primates. In Madagascar ring-tailed lemur has the nickname Maki. Lemurs are very cute, funny and kind animals. Below you will find a description and photo of the lemur, and also learn a lot of interesting things about this unusual and mysterious animal.

Primates are a group of animals that, for the most part, biological characteristics are no different from modern human populations, and its evolutionary paths diverged from the paths of humans later than all other animals. General characteristics humans and primates serve both as evidence of human evolution and as a source of ideas and doubts. Primates provide the context for the study of human evolution. Primates are an order of the mammalian class, characterized by the retention of some primitive features and the progressive development of more specialized features associated with woody way life and high degree specializations.

Characteristics of primates

It often happens that the description of a group of mammals looks unsuccessful. A formal listing 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 calcarine groove; inner finger, along on at least one pair of limbs it is opposed to the others; a thumb with or without a wide nail; a well-developed cecum; a pendulous penis; testes in the scrotum; two mammary glands." And although this description does not reflect the true beauty of primates and does not give an idea of ​​their amazing way of life, it nevertheless remains the most accurate. Modern scientists can add only two strokes to this portrait: “the shortened nasal part of the muzzle and 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 one or another feature. On the other hand, some of the mentioned characteristics are also found in other groups of animals. For example, many mammals have collarbones and three types of teeth.

The order Primates belongs to the class of mammals, the subphylum of vertebrates, and the phylum of chordates. The following characteristics are characteristic of the chordate type:

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

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

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

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

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

The class of mammals is characterized by viviparity, bearing the baby in the uterus and feeding it with milk. Mammals have a dental system with different types teeth, reflecting their food specialization - incisors, canines, premolars and molars. Milk teeth are replaced by permanent teeth. All mammals are homeothermic (this is with a constant body temperature) animals with a high level of metabolism. Their body is covered with hair, which is a derivative of the skin. Females have mammary glands. All mammals, in addition to the inner and middle ears, also have an outer ear.

Skeletal structure of representatives of the order

Quadruped lemurs, as well as most monkeys like monkeys, have retained the original structure of ancient primates. They have a long back, short and narrow rib cage, long and thin femurs, hind limbs no shorter than the front ones. These animals live mainly in trees, running or jumping along branches. A long tail plays the role of a steering wheel or balancer during jumps. Land-dwelling monkeys, such as baboons, tend to have much shorter tails.

Apes and slow-moving prosimians do not have tails. In orangutans and others great apes the back is shorter, the chest is wider, the pelvic bones are stronger. These are traits associated with 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 of primates is associated with their lifestyle (Fig. 1):

1. The spider monkey's hand with a very short thumb is characteristic of species that move by swinging their arms. 2. Gibbon: the short opposable thumb is removed from the rest involved in grasping during brachiation. 3. Gorilla: the thumb on the hand is opposed to the rest, which contributes to the precision of manipulation. 4. Macaque: A short opposable thumb allows the animal to rest on the ground with an open palm. 5. Tamarin: a long foot and claws on all fingers except the big one are characteristic of all species that cling to tree branches (in other monkeys all fingers are equipped with flat claws). 6 Siamang and 7 Orangutan: wide foot with long, gripping big toe, suitable for climbing. 8. Baboon: The long, graceful foot is good for walking on the ground.

Rice. 1 Primate limbs

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 fang, and the surfaces of the lower incisors and canines lie in the same plane, forming a dental ridge, the same as in galagos. Galagos use this comb when feeding and grooming. In leaf-eating monkeys of the Old World, for example, in thin-bodied monkeys (2), the surface of the molars is, as it were, divided into squares by four sharp projections connected by oblique ridges - it turns out good tool for grinding roughage. In apes, particularly the gorilla (3), the lower molars have five ridges and the ridges have a complex shape.

Rice. 2. General form teeth different types primates

Anatomical and physiological characteristics squad

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

Mouse lemurs are able to reproduce at the age of one year and every year they give birth to 2 cubs weighing 6.5 g after a 2-month pregnancy. The longevity record for the mouse lemur is 15 years. In contrast, a female gorilla does not become sexually mature until she is 10 years old. 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.

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

The growth rate of young primates is also low, much lower than that of other mammals of similar body mass. 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 body growth and development of reproductive organs.

Due to low rates of reproduction, primates have a fairly strong tendency to infanticide. Males often kill cubs born to other males by a female because the lactating female cannot conceive again. Males, even those at the peak of their physical development, are limited in their attempts to reproduce and do everything possible to preserve their genotype. Thus, the male Hanuman monkey has only 800 days to procreate out of 20 years of life.

Body weight varies not only among different primates, but also among 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, he goes natural selection to increase body weight. A male hanuman sometimes collects a harem of 20 females, which he has to protect from the attacks of other males. The body weight of the harem owner can be 160% of the female's weight. In contrast, in species in which males usually mate with only one female (gibbons), the sexes do not differ in size. Sexual dimorphism is very weakly expressed in lemurs. These animals live in groups, like other primates. Scientists suggest that the social structure of these animals is different from that of other primates.

It's not just body size that plays a role in the tough battle for paternity. Powerful weapons The fangs serve as fangs, which are used by males in fights and aggressive displays. 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 testes and is able to produce more sperm. This increases the likelihood of the egg being fertilized by the sperm of the record-breaking male.

Sexual competition is reflected not only in the morphology of males. In many female primates, reproductive cycles are accompanied by periodic redness and swelling of the skin in the angenital area. This pattern, clearly visible from afar, becomes most striking 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 strive 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 the desire of males to kill other people's cubs. Swollen flesh as a signal of readiness for reproduction is so important that female geladas, whose anagenal area is difficult to see because these monkeys feed while sitting, have acquired patches of skin with the same function on their chests during evolution.