2 families: platypuses and echidnas
Range: Australia, Tasmania, New Guinea
Food: insects, small aquatic animals
Body length: 30 to 80 cm

Subclass oviparous mammals represented by only one detachment - single-pass. This detachment unites only two families: platypus and echidna. single pass are the most primitive living mammals. They are the only mammals that, like birds or reptiles, reproduce by laying eggs. Oviparous feed their young with milk and therefore are classified as mammals. Female echidnas and platypuses do not have nipples, and the young lick the milk secreted by the tubular mammary glands directly from the fur on the mother's belly.

amazing animals

Echidnas and platypuses- the most unusual representatives of the class of mammals. They are called single-pass because both the intestines and the bladder of these animals open into one special cavity - the cloaca. Two oviducts in monotreme females also go there. Most mammals do not have a cloaca; this cavity is characteristic of reptiles. The stomach of oviparous is also amazing - like a bird's goiter, it does not digest food, but only stores it. Digestion takes place in the intestines. These strange mammals even have a lower body temperature than others: without rising above 36°C, it can drop to 25°C, depending on the environment, like in reptiles. Echidnas and platypuses are voiceless - they do not have vocal cords, and only young platypuses have toothless - rapidly decaying teeth.

Echidnas live up to 30 years, platypuses - up to 10. They live in forests, steppes overgrown with shrubs, and even in mountains at an altitude of up to 2500 m.

Origin and discovery of oviparous

Short Fact
Platypuses and echidnas are venomous mammals. On their hind legs they have a bone spur, through which a poisonous liquid flows. This poison causes an early death in most animals, and severe pain and swelling in humans. Among mammals, in addition to the platypus and echidna, only a representative of the order of insectivores is venomous - an open tooth and two species of shrews.

Like all mammals, oviparous descend from reptilian ancestors. However, they separated quite early from other mammals, choosing their own path of development and forming a separate branch in the evolution of animals. Thus, the oviparous were not the ancestors of other mammals - they developed in parallel with them and independently of them. Platypuses are more ancient animals than echidnas, which evolved from them, changed and adapted to the terrestrial way of life.

Europeans learned about the existence of egg-laying almost 100 years after the discovery of Australia, at the end of the 17th century. When the skin of a platypus was brought to the English zoologist George Shaw, he decided that he was simply played, the appearance of this bizarre creation of nature was so unusual for Europeans. And the fact that echidnas and platypuses reproduce by laying eggs has become one of the greatest zoological sensations.

Despite the fact that the echidna and platypus have been known to science for quite a long time, these amazing animals are still presenting new discoveries to zoologists.

wonder beast, platypus as if assembled from parts of different animals: his nose is like a duck's beak, his flat tail looks like it was taken from a beaver with a shovel, webbed paws look like flippers, but are equipped with powerful claws for digging (when digging, the membrane bends, and when walking it gathers into folds, without interfering with free movement). But for all the seeming absurdity, this beast is perfectly adapted to the way of life that it leads, and has hardly changed over millions of years.

At night, the platypus hunts for small crustaceans, mollusks and other small aquatic animals. The tail-fin and webbed paws help him to dive and swim well. The eyes, ears and nostrils of the platypus close tightly in the water, and it finds its prey in the dark under water with the help of a sensitive "beak". On this leathery "beak" are electroreceptors that can pick up weak electrical impulses emitted by movement of aquatic invertebrates. Reacting to these signals, the platypus instantly searches for prey, fills the cheek pouches, and then slowly eats the caught on the shore.

All day the platypus sleeps near the pond in a hole dug by powerful claws. The platypus has a dozen such holes, and each has several exits and entrances - not an extra precaution. To breed offspring, the female platypus prepares a special hole lined with soft leaves and grass - it is warm and humid there.

Pregnancy lasts a month, and the female lays one to three leathery eggs. Mother platypus incubates eggs for 10 days, warming them with her body. Newborn tiny platypuses, 2.5 cm long, live on their mother's belly for another 4 months, feeding on milk. The female spends most of her time lying on her back and only occasionally leaves the burrow to feed. Leaving, the platypus wall up the cubs in the nest so that no one will disturb them until she returns. At the age of 5 months, matured platypuses become independent and leave their mother's hole.

Platypuses were mercilessly exterminated because of their valuable fur, but now, fortunately, they are taken under the strictest protection, and their numbers have increased again.

A relative of the platypus, it does not look like him at all. She, like the platypus, is an excellent swimmer, but she does it only for pleasure: she does not know how to dive and get food under water.

Another important difference: the echidna has brood bag- pocket on the belly, where she puts the egg. The female, although she raises her cubs in a comfortable hole, can safely leave her - an egg or a newborn cub in her pocket is reliably protected from the vicissitudes of fate. At the age of 50 days, the little echidna already leaves the bag, but for about 5 months it lives in a hole under the auspices of a caring mother.

Echidna lives on the ground and feeds on insects, mainly ants and termites. Raking termite mounds with strong paws with hard claws, it extracts insects with a long and sticky tongue. The body of the echidna is protected by needles, and in case of danger it curls up into a ball, like an ordinary hedgehog, exposing the enemy with a prickly back.

wedding ceremony

From May to September, the mating season begins for the echidna. At this time, the female echidna enjoys special attention from males. They line up and follow her in single file. The procession is led by the female, and the grooms follow her in order of seniority - the youngest and most inexperienced close the chain. So, in a company, echidnas spend a whole month, looking for food together, traveling and relaxing.

But the rivals cannot coexist peacefully for long. Demonstrating their strength and passion, they begin to dance around the chosen one, raking the ground with their claws. The female finds herself in the center of a circle formed by a deep furrow, and the males begin to fight, pushing each other out of the ring-shaped pit. The winner of the tournament gets the favor of the female.

Insectivorous animals have the main distinguishing feature from other mammals - it is an elongated head with an elongated muzzle, significantly protruding beyond the skull, in some cases similar to a trunk. These animals belong to the order of primitive mammals. They are different in appearance and way of life. But all representatives are pretty cute and funny insectivorous animals (the photo serves as proof of this). Their limbs are five-fingered and equipped with claws. The teeth of these animals are of the insectivorous type, that is, adapted for gnawing chitin. Must have fangs. The incisors are quite long, forming pincers between themselves. covered with tubercles. The ears and eyes are small and not conspicuous. The cerebrum of insectivorous animals is primitive (the large hemispheres do not have furrows) and does not cover the cerebellum. These creatures inhabit everything except Australia and a large part of South America. Species of insectivorous animals are divided into four families: tenrec, hedgehogs, shrews and jumpers.

Fossil insectivores

Insectivorous animals are one of the most ancient groups of higher animals. Archaeologists have found their remains in the Upper Cretaceous deposits of the Mesozoic era. This is approximately 135 million years ago. In those days, there were quite a lot of insects on Earth that were food for other animals, so many ancient mammals (judging by the structure of the jaw) used them in their diet. Many species of ancient animals were larger than modern ones - dienogalerix and lepticidium. Their well-preserved remains were found in Germany, in the Eocene deposits near Messel. In general, representatives of insectivorous animals have always been small in size.

Lifestyle

Individual species of insectivorous animals lead a different lifestyle: arboreal, underground or semi-aquatic. Most are nocturnal. Some species are awake almost around the clock. The basis of the diet is, of course, insects and small underground animals. But some insectivorous animals are also predators. Some representatives eat juicy sweet fruits, and during the period of starvation, plant seeds can also become their food. The stomach of these animals is simple. absent in some species. All members of this order are polygamous. In females In males, the testicles are located in the groin or in the scrotum. Pregnancy in females lasts from a decade to one and a half months. During one year, most often there is only one litter, which can have up to 14 cubs. Insectivorous animals become full-grown in the period from 3 months to 2 years. The very appearance of animals is different, for example, hedgehogs have spines, an otter shrew has a long tail flattened on the sides, and moles have two spade-shaped forepaws.

Insectivorous animals of Russia

In our country, insectivorous animals are represented by species: moles, desmans, hedgehogs and shrews. From time immemorial, hedgehogs and shrews were considered among the people as useful animals, since they exterminate exclusively harmful insects. Moles were considered half useful animals - they destroy various soil inhabitants, including May beetle larvae, but they also eat useful earthworms. Also, breaking through their endless underground passages, moles harm forest, garden and garden plantings. But the fur of these animals is considered expensive furs, and they are objects of hunting. Earlier in Russia, desmans were also hunted.

Biological and economic importance

Insectivorous animals are links of various natural biocenoses. For example, they loosen the soil, improving its quality, and regulate the number of insects in the forest litter. For humans, their existence is also important, since these animals also eat agricultural pests. Some species of insectivorous animals are objects of fur trade (desman, moles, and others). But these animals can pose a serious danger to humans, since some of them are carriers of ticks, and with them many dangerous diseases (leptospirosis, etc.). Such rare species as the muskrat or the muskrat are listed in the Red Book and are under state protection.

Mammal classification scheme

In the class of mammals, two subclasses are distinguished: First Beasts and Real Beasts.

The subclass of the First Beasts, or Oviparous, is not numerous. It includes the platypus and echidna living in Australia and on the islands adjacent to it. First animals do not give birth to cubs, but lay eggs.

Subclass Real animals, or viviparous, includes marsupials and placental mammals.

Characteristics of the detachments of the class Mammals

Orders of mammals	Characteristic	Squad representatives
Oviparous	They lay eggs and incubate them; has a cloaca (as in reptiles); mammary glands do not have nipples.	Platypus, echidna.
marsupials	The mother carries the cub in a bag on her belly, where the mammary glands with nipples are located.	Kangaroo, koala, marsupial mouse, etc.
Insectivorous	Primitive mammals (large hemispheres are small and smooth, almost without convolutions, teeth are sharply tubercular, difficult to divide into groups), small in size.	Shrew, mole, hedgehog.
incomplete teeth	Have no or underdeveloped teeth.	Sloths, armored carrier.
Bats	The wing is a leathery membrane between the fingers of the forelimb, the sternum is changed into a keel, the bones are light and strong.	The bats.
	Most feed on animal food, the special structure of the teeth (there is a predatory tooth), are diverse in appearance and behavior.	Canine families (dog, arctic fox, wolf, foxes); Feline (lion. tiger, lynx, cat); Mustelids (marten, weasel, ferret, mink, sable); Med-vezhy (brown and polar bear).
pinnipeds	They live in the seas and oceans, have swimming membranes between the fingers (flippers), in terms of the structure of the teeth they look like predatory ones.	Harp seal, sea cat-tic.
cetaceans	They spend their whole life in water, there is no hairline, there are no hind limbs, the tail fin is located horizontally.	Dolphins, blue whale, killer whale, sperm whale.
	The most numerous detachment, they feed on solid plant foods, there are no fangs, the incisors are large and sharp (they grow all their lives as they wear out), the caecum is long and voluminous, very prolific; diverse habitats.	Squirrels, rats and mice, ground squirrels, muskrats, beavers.
artiodactyls	There are an even number of fingers on the limbs, each finger is dressed in a horny hoof cover.	Cattle, sheep, elk, reindeer, wild boar.
Unpaired-experimental	The number of fingers is odd (from one to five), each finger is covered with a horn-shaped hoof.	Horse, rhinoceros, zebra, donkey.
Lagomorphs	Animals of small size, with or without a short tail. Their teeth bear some resemblance to those of rodents. Terrestrial, poor climbers and swimmers. They inhabit forests, steppes, deserts, tundra and highlands. They feed on bark, twigs, and grass. Previously considered as part of the rodent squad.	Hare, rabbit, pika.
	Arboreal way of life, grasping limbs (opposing the thumb to all the rest), high development of the brain, mostly herd animals.	Lemur, rhesus monkey, monkeys, baboons, hamadryas, orangutans, gorillas, chimpanzees, humans.
proboscis	They belong to the order of placental mammals, their main distinguishing feature is the trunk. They are also distinguished by unique modified incisors - tusks, and are also the largest among all modern land mammals. They are herbivores.	The only representative is the Elephant (Indian, African).

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The source of information: Biology in tables and diagrams. / Edition 2e, - St. Petersburg: 2004.

Mammals are the most highly organized class of vertebrates. They are characterized by a highly developed nervous system (due to an increase in the volume of the cerebral hemispheres and the formation of the cortex); relatively constant body temperature; four-chambered heart; the presence of a diaphragm - a muscular partition separating the abdominal and chest cavities; development of cubs in the mother's body and breastfeeding (see Fig. 85). The body of mammals is often covered with hair. The mammary glands appear as modified sweat glands. The teeth of mammals are peculiar. They are differentiated, their number, form and function differ significantly in different groups and serve as a systematic feature.

The body is divided into head, neck and torso. Many have a tail. Animals have the most perfect skeleton, the basis of which is the spinal column. It is subdivided into 7 cervical, 12 thoracic, 6 lumbar, 3-4 sacral fused and caudal vertebrae, the number of the latter is different. Mammals have well-developed sense organs: smell, touch, sight, hearing. There is an auricle. The eyes are protected by two eyelids with eyelashes.

With the exception of oviparous, all mammals carry their young in uterus- a special muscular organ. Cubs are born alive and fed with milk. The offspring of mammals are more in need of further care than those of other animals.

All of these features allowed mammals to gain a dominant position in the animal kingdom. They are found all over the globe.

The appearance of mammals is very diverse and is determined by the habitat: aquatic animals have a streamlined body shape, flippers or fins; land dwellers - well-developed limbs, dense body. In the inhabitants of the air environment, the front pair of limbs is transformed into wings. A highly developed nervous system allows mammals to better adapt to environmental conditions, contributes to the development of numerous conditioned reflexes.

The mammalian class is divided into three subclasses: oviparous, marsupials, and placentals.

1. Oviparous, or first animals. These animals are the most primitive mammals. Unlike other representatives of this class, they lay eggs, but they feed their young with milk (Fig. 90). They have preserved a cloaca - part of the intestine, where three systems open - digestive, excretory and sexual. Therefore they are also called single pass. In other animals, these systems are separated. Oviparous are found only in Australia. These include only four species: echidnas (three species) and platypus.

2. Marsupials more highly organized, but they are also characterized by primitive features (see Fig. 90). They give birth to live, but underdeveloped cubs, practically embryos. These tiny cubs crawl into the pouch on the mother's belly, where, feeding on her milk, they complete their development.

Rice. 90. Mammals: oviparous: 1 - echidna; 2 - platypus; marsupials: 3 - opossum; 4 - koala; 5 - pygmy marsupial squirrel; 6 - kangaroo; 7 - marsupial wolf

Kangaroos, marsupial mice, squirrels, anteaters (nambats), marsupial bears (koala), badgers (wombats) live in Australia. The most primitive marsupials live in Central and South America. This is an opossum, a marsupial wolf.

3. Placental animals have a well developed placenta- an organ that attaches to the wall of the uterus and performs the function of exchanging nutrients and oxygen between the mother's body and the embryo.

Placental mammals are divided into 16 orders. These include insectivores, bats, rodents, lagomorphs, carnivores, pinnipeds, cetaceans, ungulates, proboscis, primates.

Insectivores mammals, which include moles, shrews, hedgehogs, and others, are considered the most primitive among placentals (Fig. 91). They are quite small animals. The number of teeth they have is from 26 to 44, the teeth are undifferentiated.

Bats- the only flying animals among animals. They are mainly crepuscular and nocturnal animals that feed on insects. These include fruit bats, bats, evenings, vampires. Vampires are bloodsuckers, they feed on the blood of other animals. Bats have echolocation. Although their eyesight is poor, due to their well-developed hearing, they pick up the echo from their own squeak, reflected from objects.

rodents- the most numerous detachment among mammals (about 40% of all animal species). These are rats, mice, squirrels, ground squirrels, marmots, beavers, hamsters and many others (see Fig. 91). A characteristic feature of rodents are well-developed incisors. They do not have roots, grow all their lives, grind down, there are no fangs. All rodents are herbivores.

Rice. 91. Mammals: insectivores: 1 - shrew; 2 - mole; 3 - tupaya; rodents: 4 - jerboa, 5 - marmot, 6 - nutria; lagomorphs: 7 - hare, 8 - chinchilla

Close to rodents detachment lagomorphs(see fig. 91). They have a similar structure of teeth, and also eat plant foods. These include hares and rabbits.

To the squad predatory belongs to more than 240 animal species (Fig. 92). Their incisors are poorly developed, but they have powerful fangs and predatory teeth that serve to tear apart the meat of animals. Predators feed on animal and mixed food. The detachment is divided into several families: canine (dog, wolf, fox), bear (polar bear, brown bear), cat (cat, tiger, lynx, lion, cheetah, panther), marten (marten, mink, sable, ferret) and etc. Some predators are characterized by hibernation (bears).

pinnipeds are also carnivores. They have adapted to life in the water and have specific features: the body is streamlined, the limbs are turned into flippers. The teeth are poorly developed, with the exception of the fangs, so they only grab food and swallow it without chewing. They are excellent swimmers and divers. They feed mainly on fish. They breed on land, along the shores of the seas or on ice floes. The order includes seals, walruses, fur seals, sea lions, etc. (see Fig. 92).

Rice. 92. Mammals: carnivores: 1 - sable; 2 - jackal; 3 - lynx; 4 - black bear; pinnipeds: 5 - harp seal; 6 - walrus; ungulates: 7 - horse; 8 - hippopotamus; 9 - reindeer; primates: 10 - marmoset; 11 - gorilla; 12 - baboon

To the squad cetaceans the inhabitants of the waters also belong, but, unlike the pinnipeds, they never go to land and give birth to their young in the water. Their limbs have turned into fins, and in the shape of the body they resemble fish. These animals have mastered the water for the second time, and in connection with this they have many features characteristic of aquatic inhabitants. However, the main features of the class have been preserved. They breathe atmospheric oxygen through their lungs. Cetaceans include whales and dolphins. The blue whale is the largest of all modern animals (length 30 m, weight up to 150 tons).

Ungulates subdivided into two orders: equine and artiodactyl.

1. TO equids include horses, tapirs, rhinos, zebras, donkeys. Their hooves are modified middle fingers, the remaining fingers are reduced to varying degrees in different species. Ungulates have well-developed molars, as they feed on plant foods, chewing and grinding it.

2. At artiodactyls the third and fourth fingers are well developed, turned into hooves, which account for the entire body weight. These are giraffes, deer, cows, goats, sheep. Many of them are ruminants and have a complex stomach.

To the squad proboscis belong to the largest of land animals - elephants. They live only in Africa and Asia. The trunk is an elongated nose, fused with the upper lip. Elephants do not have fangs, but powerful incisors have turned into tusks. In addition, they have well-developed molars that grind plant food. These teeth change in elephants 6 times during their lives. Elephants are very voracious. One elephant can eat up to 200 kg of hay per day.

Primates combine up to 190 species (see Fig. 92). All representatives are characterized by a five-fingered limb, grasping hands, nails instead of claws. The eyes are directed forward (primates have a developed binocular vision). |
§ 64. Birds9. Fundamentals of ecology

Many mammals are partially aquatic, living near lakes, streams, or ocean shorelines (eg seals, sea lions, walruses, otters, muskrats, and many others). Whales and dolphins () are completely aquatic and can be found in all and some rivers. Whales can be found in polar, temperate and tropical waters, both near shore and in the open ocean, and from the surface of the water to depths of more than 1 kilometer.

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

Mammal groups

Baby kangaroo in mother's pouch

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

• Monotremes or oviparous (Monotremata) lay eggs, which is the most primitive reproductive feature in mammals.
• marsupials (Metatheria) are characterized by the birth of underdeveloped young after a very short gestation period (8 to 43 days). Offspring are born at a relatively early stage of morphological development. The cubs are attached 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.

Lifespan

Just as mammals vary greatly in size, so does their lifespan. 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 more decades in natural conditions, which is significantly longer than the lifespan of some larger mammals. Life expectancy ranges from 1 year or less to 70 years or more in the wild. Bowhead whales can live for over 200 years.

Behavior

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

There are species of mammals that exhibit almost every type of lifestyle, including vegetative, aquatic, terrestrial, and arboreal. Their ways of moving around their habitat are varied: mammals can swim, run, fly, glide, and so on.

Social behavior also varies considerably. Some species can live in groups of 10, 100, 1000 or more individuals. Other mammals are generally solitary except when mating or rearing offspring.

The nature of activity among mammals also covers the full range of possibilities. Mammals can be nocturnal, diurnal, or crepuscular.

Nutrition

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

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

Among land mammals there are herbivores, omnivores and carnivores. Each individual takes its place in.

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 impact on populations of their food preferences.

reproduction

Mammals tend to 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 young.

Generally, most mammalian species are either polygynous (one male mates with several females) or promiscuous (both males and females have multiple matings in a given breeding season). Since females carry and nurse their offspring, it often happens that male mammals can produce many more offspring during the mating season than females. As a consequence, the most common mating system in mammals is polygyny, with relatively few males fertilizing many females. At the same time, a large number of males do not participate in reproduction at all. This scenario sets the stage 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, whereby males are better able to compete for access to females. Only about 3% of mammals are monogamous and only mate with the same female each season. In these cases, males may even participate in the upbringing of offspring.

As a rule, the reproduction of mammals depends on their habitat. For example, when resources are scarce, males spend their energy breeding with a single female and provide food and protection for the young. If, however, resources are plentiful and the female can ensure the well-being of her offspring, the male goes to other females. In some mammals, polyandry is also common, when a female has bonds with several males.

In most mammals, the embryo develops in the uterus of the female until it is fully formed. The born cub is fed with mother's milk. In marsupials, the embryo is born underdeveloped, and its further development takes place in the mother's pouch, as well as feeding with mother's milk. When the calf reaches full development, it leaves the mother's pouch, but can still spend the night in it.

Five species of mammals that belong to the order Monotremes actually lay eggs. Like birds, representatives of this group have a cloaca, which is a single opening that serves for emptying and reproduction. The 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 their offspring with milk.

The offspring need to grow, develop and maintain optimal body temperature, but feeding the young with nutrient-rich milk takes a lot of energy from the female. In addition to producing nutritious milk, the female is forced to protect her offspring from all sorts of threats.

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

Role in the ecosystem

The ecological roles or niches filled by more than 5,000 mammal species are varied. Each mammal has its place in the food chain: there are omnivores, carnivores and their prey - herbivorous mammals. Each species, in turn, affects. Due in part to their high metabolic rates, the impact that mammals have on nature is often disproportionate to their abundance. Thus, many mammals may be carnivores or herbivores 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 to other groups of animals, mammals have a significant impact on the global.

Significance for a person: positive

Mammals are important to mankind. Many mammals have been domesticated to provide humankind with foods such as meat and milk (such as cows and goats) or wool (sheep and alpacas). Some animals are kept as service or pets (eg dogs, cats, ferrets). Mammals are also important to the ecotourism industry. Think of the many people who go to zoos or all over the world to see animals such as whales or whales. Mammals (eg bats) often control pest populations. Some animals, such as rats and mice, are vital to medical and other scientific research, while other mammals can serve as models in human medicine and research.

Significance for a person: negative

plague epidemic

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

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

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

Security

Overexploitation, habitat destruction and fragmentation, 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. About 25% (1,000) of mammal species are currently listed on the IUCN Red List, as they are at various risks of extinction.

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

Finally, it negatively affects flora and fauna. The geographic ranges of many mammals change due to changes in temperature. As temperatures rise, which is especially noticeable in the polar regions, some animals are unable to adapt to new conditions, and therefore may disappear.

Protective measures include tracking habitats and carrying out a set of measures to protect mammals.