About animals

Characterization, classification, habitat, importance and protection of mammals

Pin
Send
Share
Send


The mammals class includes about 4000 species, uniting in 19 orders.

First Beast Subclass (Prototheria)Subclass Beasts (Theria)
1. Squad One-pass, or Clokachny (Monotremata)1. Infraclass Lower Beasts, or Marsupials (Metatheria, Marsupialia) a) squad Marsupials (Marsupialia) 2. Infraclass Higher Beasts, or Placental (Eutheria, Placentalia) 19 squads

1. Subclass of the First Beasts (Prototeria)

The most primitive of the living mammals. Lay eggs, hatching them (platypus), or carrying them in a brood bag (echidna). There is a cesspool. There is no corpus callosum in the brain. The mammary glands have a tubular structure. There are no nipples, and the ducts of the mammary glands open to the surface of the skin in the glandular fields. In females, only the left ovary functions. Body temperature is lower than that of other mammals (about 32 0 С). In the unit Single pass 2 families:

a) echidna - the body is covered with needles, the muzzle is elongated, has a beak, legs are armed with sharp claws. 3 species found in Australia and New Guinea,

b) platypuses - the body is covered with thick hair, swimming membranes are located between the fingers, on the inner surface of the beak there are numerous horny plates with which the platypus drains food from the water. 1 species living in Australia and Tasmania.

2. Subclass of the Beasts (Theria)

I) Infraclass Lower Beasts (Metatheria)

1) Squad Marsupials (Marsupialia)

About 250 species, diverse in size and ecology. Common signs: give birth to underdeveloped cubs, carrying them in a bag. On the inside of the bag there are nipples into which the ducts of the mammary glands open. The duration of pregnancy is short (from 8 to 40 days). The skeleton is characterized by the presence of marsupial bones attached to the pubic, the coracoid merges with the scapula. Teeth are variable in number and structure.

Distributed in Australia, Oceania, South America, where they occupy ecological niches of the corresponding placental mammals that are absent in these regions.

9 families: possums (84 species), predatory marsupials (marsupial wolf, marsupial anteater), marsupial badgers, or bandicoots (19 species), couscous (marsupial bear - koala), kangaroo (51 species).

II) Infraclass Higher Beasts, or Placental (Eutheria, Placentalia)

Distributed everywhere. They are distinguished by the development of the cortex of the forebrain hemispheres, connected by the corpus callosum, there is always a placenta, there are no brood sacs and marsupials, the cubs at birth are more or less developed. About 17 units.

1) Detachment Insectivorous (Insectivora)

Primitive placental small and medium sizes (3.5-44 cm). The hairline is short, represented mainly by the undercoat, some of the remaining hair turns into needles. Teeth with weak heterodontism. Extremities stop-moving. In the brain, the olfactory lobes are highly developed, the cerebral cortex is almost without convolutions. Distributed everywhere, except for Australia, Antarctica and most of South America. There are 370 species in the squad, 7 families:

Hedgehogs (15 species), moles (20 species), tenreks (31 species), shrews (270 species), jumpers (14 species).

2) Sherstokryly detachment, or Kaguany (Dermoptera)

2 species of khaguan living in the tropical forests of Southeast Asia. Leather membranes are stretched between the front and hind limbs. On the bare soles of the paws, there are flat platforms forming suction discs. Sternum with a small keel. Able to plan a distance of up to 60 m. They feed on foliage of trees and fruits.

3) Chipwing (Chiroptera)

About 850 species of mammals adapted to flight. The skin membrane is stretched between 2-5 fingers of the forelimbs, forearm, shoulder, sides of the body, hind limbs and tail. The short first finger of the forelimbs is free, ends with a claw. A head with a wide mouth gap, small eyes and large, complexly arranged auricles with a skin outgrowth (tragus) at the base of the ear canal. The ulnar and tibia are rudimentary, the clavicles are well developed, the sternum has a small keel. Nocturnal animals, well-developed hearing and touch. The ability to echolocation is characteristic. 2 suborders:

a) suborder of winged birds - 1 family (winged wings), 146 species,

b) the bats suborder - 16 families (horseshoes, common bats, bulldogs, etc.), 700 species.

4) Squad Primates (Primates)

About 190 species. They lead a tree lifestyle, limbs five-fingered, stop-walking. The first finger is opposed to the rest (grasping limbs). In the skull there is a large cerebral region with eye sockets directed forward (binocular vision). The stomach is simple, there is a cecum, because plant foods are dominant. They are distinguished by large brain sizes, complex behavior. 2 suborders:

a) suborder lower primates, or semi-apes — about 90 species of small and medium primitive primates (tupai, lemur, lori families),

b) suborder higher primates, or monkeys - more than 100 species of highly developed primates (capuchin family, marmosets, monkeys, anthropoids).

5) Detachment Edentata

A few specialized animals that live in South, Central and southern North America. The underdevelopment of the dental system is characteristic: teeth are missing or lacking in enamel, have constant growth and are almost undifferentiated. About 30 species, 3 families: anteaters (3 species), sloths (5 species), armadillos (20 species).

6) Squad of the Lizards (Pholidota)

1 family with 7 species. The body above is covered with horn scales, the limbs are armed with strong claws. They live in the forests and savannahs of Africa and Southeast Asia. Ground and woody forms, active at night. They feed on ants and termites, catching them with a long moving tongue.

7) Squadron-like order (Lagomorpha)

They differ from rodents in the structure of the bony palate, which has the appearance of a narrow bridge between the upper dentition and the presence of upper double incisors. The hairline is diverse - from thick fluffy to rare bristly. Herbivorous. About 60 species, 2 families - pikas (short-eared and short-footed burrowing animals) and hares (long-eared and long-footed).

8) Rodent Squad (Rodentia)

The largest group of modern mammals (about 2000 species, 32-34 families). They are found everywhere, mainly of small and medium size. Herbivorous. The incisors are powerful, constantly growing, there are no fangs, a gap is formed in their place - a diastema. The digestive tract is long, there is a large cecum. They are distinguished by high precocity and fertility. Great value in natural ecosystems and for humans. There are commercial species, there are many distributors and carriers of pathogens of dangerous diseases, agricultural pests and agricultural crops. Participate in soil formation and the formation of vegetation.

According to the device of the chewing apparatus are divided into 3 groups:

a) protein-like rodents - the beaver family, squirrel (marmots, ground squirrels, squirrels and chipmunks), flying squirrels, spines,

b) mouse-like rodents - Sonya family, jerboas, mice, mouse, hamster-like, field voles, mole rats.

c) porcupine-like rodents - porcupine families, guinea pigs, capybaras, agouti, chinchillas, nutria, mole rats, etc.

9) Cetacean Squad (Cetacea)

About 80 living species. Secondary-water animals do not go on land. The body shape is fish-shaped, the head is large, there is no cervical interception. The forelimbs are transformed into flippers, the hind limbs are reduced. The skin is naked, hairless, with a thick layer of subcutaneous fat. The caudal part of the body is very mobile and has a skin fin with horizontal lobes. The lumbosacral and caudal regions are reduced in the skeleton, only rudiments of the pelvic girdle are preserved from the hind limbs. The jaw is elongated in the skull. The lungs are resilient and elastic, with large tidal volume. Alveoli are blocked by sphincters that hold air when immersed. They feed on plankton or large animal prey. 2 suborders:

a) suborder baleen whales - families of smooth whales, gray whales, minke whales, humpback whales,

b) the suborder tooth whales - families of sperm whales, beaks, dolphins.

10) Predatory Squad (Carnivora)

Mostly carnivores, plant foods are of subordinate importance. The incisors are small, the fangs are always well developed, the molars are tuberous, with sharp cutting edges, the last of the pre-root upper jaw and the first root lower are predatory teeth (differ in size and sharpness). Well-developed hairline. Widespread, 240 species, about 7 families: canine (wolf, fox, arctic fox, raccoon dog), raccoons (raccoon-raccoon), bears, marten (weasel, ermine, sable, ferret, marten), feline, hyenas, wyverns ( mongooses).

11) Pinnipedia Squad (Pinnipedia)

About 30 species. Spend most of the time in the water, going ashore for rest, mating, giving birth to young and molting. Hairline from stiff outer hair. Under the skin is a thick layer of fat, the body is streamlined. The front and hind limbs are turned into flippers, a thick, leathery membrane is developed between the fingers. The teeth are conical, slightly differentiated. The lungs are large, large reserves of myoglobin in the muscles (provides a reserve of oxygen when diving). Milk has a very high fat content (up to 43%). 3 families - eared seals (fur seals, sea lions, sea lions), real seals (harp seal, sea hare), walruses.

12) Squid Tooth (Tubulidentata)

1 species - African aardvark. It has only molars, which are fused dentin tubules, not coated with enamel. In appearance, it resembles an edentulous (anteaters and sloths).

13) Squad Damans, or Fats (Hyracoidea)

10 species of small and medium-sized animals, similar to tailless gophers. On the front legs, 4 fingers with flattened claws resembling hooves, on the hind legs - 3 fingers. Close to the proboscis.

14) Proboscis squad (Proboscidea)

It is represented by 2 species - African and Indian elephants. The largest land animals. The nose and upper lip are fused to the trunk - the main grasping organ, also involved in the touch and sniffing of objects. The limbs are five-fingered, with small hooves and a flat foot. The skin is thick, bare. The upper paired incisors - tusks - grow all their lives, reaching large sizes. The female, after 1.5-2 years of pregnancy, gives birth to 1 cub weighing 100 kg.

15) Sirenia Squad

Aquatic animals, to date, 4 species have survived. The body shape resembles cetaceans, but the neck is well expressed. The forelimbs are in the form of fins, on which rudimentary hooves are preserved. There are no hind limbs. Molar teeth with a flat chewing surface, the stomach is complex, consists of several departments. They feed on underwater vegetation, grazing in underwater meadows. 2 families - manatees (3 species) and dugongs (1 species).

16) Detachment of Oryx (Perissodactyla)

Large animals with the most developed 3 fingers (in some species, only he retains one). The degree of reduction of the remaining fingers corresponds to the speed of running. The terminal phalanges of the fingers are covered with horn hooves. There are no collarbones in the shoulder girdle. The stomach is simple. 16 species, 3 families - tapirs, rhinos and horses.

17) Order Artiodactyla (Artiodactyla)

Large and medium animals with high legs, capable of fast running. Extremities 4-fingered: 3 and 4 fingers are long and serve as a support (dressed with hooves), and 2 and 5 fingers are reduced. No collarbones. Herbivorous. The stomach in most consists of several sections. Mostly herd animals. About 170 species, 3 suborders:

a) non-ruminant suborder - families of pork, bakers and hippos,

b) ruminant suborder - families of deer, musk deer, deer, deer, giraffes, bovids, bulls,

c) the corpus callosum suborder is a family of camels.

Did not find what you were looking for? Use the search:

Best sayings:Only a dream brings the student to the end of the lecture. But someone else's snoring puts him off. 8919 - | 7596 - or read all.

5.18.181.131 © studopedia.ru He is not the author of the materials that are posted. But provides the opportunity for free use. Is there a copyright violation? Write to us | Feedback.

Disable adBlock!
and refresh the page (F5)

very necessary

Description

Mammals - a class of vertebrate animals, which is divided into 21-29 orders (depending on various classifications). All mammals have at least three characteristics not found in other animals: 3 bones in the middle ear, hair and the ability to produce milk by the mammary glands of females.

And although mammals have several common characteristics, the class Mammalia contains a huge variety of forms. The smallest mammals can be found among shrews and bats, and they can weigh only a couple of grams. The largest mammal and largest animal that has ever lived on the planet is the blue whale, which can weigh up to 200 tons. Thus, the weight of the largest mammal is 53 million times more than the smallest. Mammals have evolved to occupy a wide variety of ecological niches and have developed numerous adaptations that allow them to adhere to different lifestyles.

Analysis of parts of speech

Next, let's analyze the morphological features of each part of the speech of the Russian language by examples. According to the linguistics of the Russian language, there are three groups of 10 parts of speech, according to common features:

1. Independent parts of speech:

  • nouns (see morphological norms noun),
  • Verbs:
    • Communion
    • Communion,
  • adjectives
  • numerals
  • pronouns
  • adverbs

2. Service parts of speech:

3. Interjection.

None of the classifications (according to the morphological system) of the Russian language fall into:

  • words yes and no if they act as independent sentences.
  • introductory words: so, by the way, total, as a separate sentence, as well as a number of other words.

Morphological analysis of a noun

  • the initial form in the nominative case, singular (with the exception of nouns used only in the plural: scissors, etc.),
  • own or common,
  • animate or inanimate
  • gender (m, f, cf.),
  • number (unit, pl.),
  • declination
  • case
  • syntactic role in the sentence.

Morphological analysis of the noun

"The kid drinks milk."

Kid (answers the question of who?) - a noun,

  • initial form - baby,
  • permanent morphological characters: animated, common, concrete, masculine, 1st declination,
  • inconsistent morphological features: nominative case, singular,
  • when parsing a sentence, it acts as a subject.

Morphological analysis of the word “milk” (answers the question of whom? What?).

  • the initial form is milk,
  • constant morphological characteristic of the word: neuter, inanimate, material, common noun, 2nd declination,
  • mutable morphological characters: accusative, singular,
  • the offer is a direct addition.

Here is another example of how to make a morphological analysis of a noun based on a literary source:

"Two ladies ran to Luzhin and helped him up. He began to knock dust off his coat with his palm. (Example from:" Luzhin's Defense, "Vladimir Nabokov)."

Ladies (who?) - a noun,

  • the initial form is a lady,
  • permanent morphological characters: common noun, animate, concrete, feminine, I declination,
  • fickle morphological characteristic of a noun: singular, genitive,
  • syntactic role: part of the subject.

Luzhin (to whom?) - a noun,

  • initial form - Luzhin,
  • true morphological characteristic of the word: proper name, animate, concrete, masculine, mixed declination,
  • inconsistent morphological features of a noun: singular, dative case,
  • syntactic role: addition.

Palm (what?) - a noun,

  • the initial form is the palm,
  • permanent morphological features: feminine, inanimate, common noun, concrete, I declination,
  • inconsistent morpho. signs: singular, instrumental,
  • syntactic role in context: complement.

Dust (what?) Is a noun,

  • the initial form is dust,
  • main morphological features: common noun, material, feminine, singular, animate not described, III declension (noun with zero ending),
  • fickle morphological characteristic words: accusative,
  • syntactic role: addition.

(c) Coat (Why?) - a noun,

  • the initial form is a coat,
  • constant correct morphological characteristic of the word: inanimate, common noun, concrete, neuter, indeclinable,
  • morphological signs are inconsistent: the number by context cannot be determined, genitive,
  • syntactic role as a member of a sentence: addition.

Morphological analysis of the adjective

The name adjective is a significant part of speech. Answers questions Which? Which one? Which one? What kind? and characterizes the features or qualities of the subject. Table of morphological features of the name of the adjective:

  • initial form in the nominative case, singular, masculine,
  • permanent morphological features of adjectives:
    • discharge, according to the value:
      • - high-quality (warm, silent),
      • - relative (yesterday, reading),
      • - possessive (hare, mother),
    • degree of comparison (for qualitative, for which this attribute is constant),
    • full / short form (for high-quality, for which this attribute is permanent),
  • inconsistent morphological features of the adjective:
    • high-quality adjectives vary in degree of comparison (in comparative degrees the simple form, in the excellent - complex): beautiful-prettier-the most beautiful,
    • full or short form (only high-quality adjectives),
    • trait of the genus (singular only),
    • number (consistent with the noun)
    • case (consistent with the noun)
  • syntactic role in a sentence: an adjective is a definition or part of a compound nominal predicate.

Morphological analysis of the adjective

A full moon rose over the city.

Full (what?) Is an adjective,

  • the initial form is full,
  • permanent morphological features of the adjective name: qualitative, full form,
  • inconsistent morphological characteristic: in a positive (zero) degree of comparison, feminine gender (consistent with a noun), nominative case,
  • for parsing - a minor member of the sentence, performs the role of definition.

Here is a whole literary passage and morphological analysis of the name of the adjective, with examples:

The girl was beautiful: slender, thin, blue eyes, like two amazing sapphires, looked into your soul.

Beautiful (what?) Is an adjective,

  • the initial form is beautiful (in this meaning),
  • constant morphological norms: high-quality, short,
  • inconsistent signs: positive degree of comparison, singular, feminine,
  • syntactic role: part of the predicate.

Slender (what?) - an adjective name,

  • the initial form is slender,
  • permanent morphological features: quality, complete,
  • inconsistent morphological characteristic of the word: full, positive degree of comparison, singular, feminine, nominative case,
  • syntactic role in a sentence: part of the predicate.

Thin (what?) Is an adjective,

  • the initial form is thin,
  • morphological permanent features: quality, complete,
  • inconstant morphological characteristic of the adjective: positive degree of comparison, singular, feminine, nominative,
  • syntactic role: part of the predicate.

Blue (what?) Is an adjective,

  • initial form is blue,
  • table of constant morphological features of the name of the adjective: qualitative,
  • inconsistent morphological characteristics: full, positive degree of comparison, plural, nominative case,
  • syntactic role: definition.

Amazing (what?) - the name is an adjective,

  • the initial form is amazing
  • permanent morphological features: relative, expressive,
  • inconsistent morphological features: plural, genitive,
  • syntactic role in a sentence: part of the circumstance.

Morphological characteristics of the verb

According to the morphology of the Russian language, a verb is an independent part of speech. It can denote the action (walk), property (limp), attitude (equal), state (rejoice), sign (whiten, show off) of the subject. Verbs answer the question what to do? what to do? what is he doing? what did you do? or what will do? Different groups of verbal word forms are characterized by heterogeneous morphological characteristics and grammatical features.

Morphological forms of verbs:

  • the initial form of the verb is infinitive. It is also called the indefinite or unchanging form of the verb. There are no inconsistent morphological features,
  • conjugated (personal and impersonal) forms,
  • non-conjugated forms: participial and participial.

Morphological analysis of the verb

  • the initial form is infinitive,
  • permanent morphological features of the verb:
    • transitivity:
      • transitive (used with accusative nouns without an excuse),
      • intransitive (not used with a noun in the accusative case without an excuse),
    • recoverability:
      • returnable (yes, yes)
      • irrevocable (no, -s),
    • view:
      • imperfect (what to do?)
      • perfect (what to do?)
    • conjugation:
      • I conjugation (do-do, do-do, do-do, do-do, do-do / ut),
      • II conjugation (one hundred, one hundred, one hundred, one hundred, one hundred / at),
      • slobbery verbs (want, run),
  • unstable morphological signs of the verb:
    • mood:
      • indicative: what did? What did you do? what is he doing? what will do ?,
      • conditional: what would he do? what would you do ?,
      • imperative: do it !,
    • tense (in indicative mood: past / present / future),
    • person (present / future tense, indicative and imperative: 1 person: I / we, 2 person: you / you, 3 person: he / they),
    • gender (in the past tense, singular, indicative and conditional)
    • number,
  • syntactic role in the sentence. Infinitive can be any member of a sentence:
    • predicate: Be a holiday today,
    • subject: Learning is always useful,
    • addition: All guests asked her to dance,
    • definition: He had an irresistible urge to eat,
    • circumstance: I went out for a walk.

Species of mammals

This class of animals has more than 5 thousand living species, including humans. Homo sapiens. It is estimated that the total number of species of the class exceeds 20 thousand, including extinct mammals. Mammal species can range from very tiny to truly huge.

The species diversity of mammals primarily depends on the specific characteristics inherent in a particular group of animals. Based on these features, as well as behavior, range and habitat, the ability to interbreed, and give stronger offspring, adaptations to environmental changes, and other factors, scientists attribute animals to a specific species or describe a new one.

Mammalian characteristics

  • One of the main characteristics that mammals have is wool, fur, or hair. This feature is useful for maintaining a constant body temperature, which is important for all warm-blooded (endothermic) animals.
  • Another characteristic is the ability to produce milk. This is necessary for feeding cubs, which are usually born fully developed (exceptions are single-pass and marsupials). Fertilization occurs in the reproductive organs of females, and most of them have a placenta, which provides nutrients to the developing embryo.
  • Mammal cubs usually slowly emerge from the nest, which allows parents to train their offspring with the skills necessary for survival.
  • The respiratory and circulatory features of mammals include a diaphragm for proper ventilation of the lungs and a heart in which there are four chambers to ensure proper blood circulation.
  • Mammals can comprehend and study various things. This is possible due to the larger brain size compared to other vertebrates of a similar size.
  • Finally, the existence of teeth that differ in size and function is a feature observed among mammals.

All these characteristics make mammals unique representatives of the animal world.

Habitat and distribution

Mammals are distributed around the world, in the oceans and seas, on continents and islands, and are found in various habitats. On land, mammals are common in all biomes, from the hot desert to the cold tundra, from meadows and forests to high altitude zones.

Many mammals are partially aquatic, living near lakes, streams or coastlines of the oceans (for example, seals, sea lions, walruses, otters, muskrats and many others). Whales and dolphins (cetaceans) are completely aquatic and can be found in all the oceans of the world and some rivers. Whales can be found in polar, temperate and tropical waters, both near the coast and in the open ocean, and from the surface of the water to a depth of more than 1 kilometer.

The habitat of mammals is also characterized by different climatic conditions. For example, a polar bear lives quietly at freezing temperatures, while lions and giraffes need a warm climate.

Mammalian groups

There are three main groups of mammals, each of which is characterized by one of the main features of embryonic development.

  • Single pass or ovipositing (Monotremata) lay eggs, which is the most primitive reproductive feature in mammals.
  • Marsupials (Metatheria) are characterized by the birth of immature cubs after a very short period of pregnancy (from 8 to 43 days). Offspring are born at a relatively early stage of morphological development. The cubs attach to the mother’s nipple and sit in the bag, where their subsequent development takes place.
  • Placental (Placentalia) are characterized by long gestation (pregnancy), during which the embryo interacts with its mother through a complex embryonic organ - the placenta. After birth, all mammals depend on the milk of their mothers.

Life span

Just as mammals vary greatly in size, their lifespan also varies. As a rule, small mammals live less than larger ones. Bats (Chiroptera) are an exception to this rule - these relatively small animals can live for one or several decades in vivo, which is much longer than the life expectancy of some larger mammals. Life expectancy ranges from 1 year or less, to 70 or more years in the wild. Greenland whales can live more than 200 years.

Behavior

The behavior of mammals varies significantly among species. Since mammals are warm-blooded animals, they need more energy than cold-blooded animals of the same size. Mammalian activity indicators reflect their high energy requirements. For example, thermoregulation plays an important role in the behavior of mammals. Those animals that live in colder climates should warm their bodies, while mammals living in hot and dry climates need to cool to keep moisture in their bodies. Behavior is an important way for mammals to maintain physiological balance.

There are mammalian species that exhibit almost every type of lifestyle, including plant, aquatic, terrestrial and arboreal. Their methods of movement in their habitat are diverse: mammals can swim, run, fly, glide, etc.

Social behavior also varies greatly. Some species can live in groups of 10, 100, 1000 or more individuals. Other mammals are usually solitary, except in cases of mating or raising offspring.

The nature of activity among mammals also covers the entire spectrum of possibilities. Mammals can be nocturnal, diurnal, or twilight.

Nutrition

Most mammals have teeth, although some animals, such as baleen whales, have lost them during evolution. Because mammals are widespread in a variety of habitats, they have a wide range of feeding methods and preferences.

Marine mammals feed on a variety of prey species, including small fish, crustaceans, and sometimes other marine mammals.

Among terrestrial mammals, herbivorous, omnivorous and carnivorous animals are found. Each individual takes its place in the food chain.

Being warm-blooded, mammals require much more food than cold-blooded animals of the same size. Thus, a relatively small number of mammals can have a large effect on the populations of their food preferences.

Breeding

Mammals, as a rule, reproduce sexually and have internal fertilization. Almost all mammals are placental (with the exception of oviparous and marsupials), that is, they give birth to live and developed cubs.

Usually, most mammalian species are either polygynous (one male mates with several females) or random (both males and females have multiple connections in a given breeding season). Since females carry and feed offspring, it often happens that male mammals can produce much more offspring during mating than females. As a result, polygyny is the most common mating system in mammals, and a relatively small number of males fertilize many females. At the same time, a large number of males do not participate in breeding at all. This scenario creates the basis for intense competition between males among many species, and also allows females to choose a stronger mating partner.

Many mammalian species are characterized by sexual dimorphism, as a result of which males can better compete for access to females. Only about 3% of mammals are monogamous and mate with only one and the same female each season. In these cases, males can even participate in the offspring.

As a rule, the reproduction of mammals depends on their habitat. For example, when resources are insufficient, males spend their strength on breeding with one female and provide cubs with food and protection. If, however, resources are abundant and the female can ensure the well-being of her offspring, the male leaves for other females. Polyandry is also common in some mammals, when the female has connections with several males.

In most mammals, the embryo develops in the female uterus until it is fully formed. Born babies are fed breast milk. In marsupials, the embryo is born underdeveloped, and its further development occurs in the mother’s bag, as does feeding the mother’s milk. When the cub reaches full development, he leaves the mother's bag, but can still spend the night in it.

Five species of mammals, which belong to the monotremes order, actually lay eggs. Like birds, representatives of this group have a cesspool, which is a single hole that serves for emptying and breeding. Eggs develop inside the female and receive the necessary nutrients for several weeks before laying. Like other mammals, monotremes have mammary glands and females feed offspring with milk.

Offspring need to grow, develop and maintain optimal body temperature, however, feeding the young with milk saturated with nutrients takes a lot of energy from the female. In addition to developing nutritious milk, the female is forced to protect her offspring from all sorts of threats.

In some species, the cubs remain with their mother for a long time and learn the necessary skills. Other species of mammals (such as artiodactyl animals) are already born quite independent and do not need excessive care.

Role in the ecosystem

Ecological roles or niches filled with more than 5000 species of mammals are different. Each mammal takes its place in the food chain: there are omnivores, carnivores, and their victims are herbivorous mammals. Each species, in turn, affects ecosystems. Partly due to their high metabolic rates, the effect of mammals on nature is often disproportionately large in relation to their numerical abundance. Thus, many mammals can be predatory or herbivorous in their communities, or play an important role in seed dispersal, or pollination. Their role in the ecosystem is so diverse that it is difficult to generalize. Despite their low species diversity, compared with other groups of animals, mammals have a significant impact on global biodiversity.

Significance for a person: positive

Mammals are an important biological resource for humanity. Many mammals have been domesticated to provide humanity with products such as meat and milk (such as cows and goats) or wool (sheep and alpacas). Some animals are kept as service or domestic animals (e.g. dogs, cats, ferrets). Mammals are also important for the ecotourism industry. Think of the many people who go to zoos or all over the world to see animals such as elephants, lions or whales. Mammals (e.g. bats) often control the population of agricultural pests. Some animals, such as rats and mice, are vital for medical and other scientific research, while other mammals can serve as models in medicine and human research.

Human value: negative

It is believed that some species of mammals have a detrimental effect on human interests. Many species that eat fruits, seeds, and other vegetation are pests. Carnivores are often considered a threat to livestock or even to human life. Mammals that are common in urban or suburban areas can be a problem if they damage cars when they get on the road or become domestic pests.

Several species coexist well with humans, including domesticated mammals (such as rats, domestic mice, pigs, cats and dogs). However, as a result of deliberate or unintentional introduction of invasive (non-native) species into ecosystems, they negatively affected the local biodiversity of many regions of the world, especially the endemic island biota.

Many mammals can transmit diseases to humans or livestock. The bubonic plague is considered the most famous example. This disease is spread by fleas that are carried by rodents. Rabies is also a significant threat to livestock and can also kill people.

Security

Excessive exploitation, destruction and fragmentation of the habitat, the introduction of invasive species and other anthropogenic factors threaten the mammals of our planet. Over the past 500 years, at least 82 species of mammals are considered extinct. Currently, about 25% of the species (1 thousand) of mammals have been listed on the IUCN Red List, as they are at different risk of extinction.

Species that are rare or require large ranges are often at risk due to habitat loss and fragmentation. Animals that are known to threaten people, livestock, or crops can die at the hands of humans. Those species that are exploited by humans as a biological resource (for example, to produce meat or fur), but not domesticated, are often depleted to critically low levels.

Finally, global climate change negatively affects flora and fauna. The geographical habitats of many mammals are changing due to temperature changes. As the temperature rises, which is especially noticeable in the polar regions, some animals are unable to adapt to new conditions, therefore, they may disappear.

Conservation measures include tracking the habitats of endangered species and carrying out a range of measures to protect mammals.

Pin
Send
Share
Send