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Sirens (a detachment of aquatic mammals). Squad Sirens - Sirenia In what water does the siren live

lake siren(lat. Siren Lacertina) is an incredibly specific animal, which is also found exclusively in stagnant water bodies of the Southeastern United States. A long snake-like body, only one pair of limbs (!), external feathery gills... a very unusual combination for... an amphibian.

Lake siren or large siren is a rather large amphibian from the order of tailed amphibians from the siren family. Its long serpentine body can reach 90 cm, but often does not exceed 70 cm. the hind limbs are completely absent - their rudiments are absent even on the skeleton.

Outwardly, lake sirens are quite similar to conger eels: the coloration, shape of the head and narrow yellow, brown or gray stripes stretching through the entire body to the tip of the tail practically repeat those of electric fish. The only clearly distinguishable difference is the external feathery gills, which are located on both sides of the head.

Sirens are not particularly demanding on environmental conditions, all they need for full development is a pond with stagnant water or a swamp. However, despite the fact that these amphibians tolerate prolonged drought relatively easily, they are found only in the Southeast of the United States: Virginia, North Carolina, South Carolina, Alabama, Georgia and Florida. Interestingly, all other representatives of the sirenaceae are also found only in this region.

In choosing food, large sirens are also not particularly picky and hunt almost any prey that they are able to swallow: fry, tadpoles, molluscs, caviar ... The mouth of animals is small, and teeth are missing as such, so they have to eat a lot and often.

Like many amphibians, sirens are nocturnal, but during the day they prefer to hide at the bottom of a reservoir or at least hide under stones.

All sirens are very well adapted to prolonged droughts, falling into hibernation and forming a kind of cocoon of mucus and dirt around themselves, they are able to wait for the rainy season for several months.

Sirens(Sirenia), an order of aquatic mammals. 3 families: manatees(3 species), dugongs (Dugongidae, with 1 species - dugong) and Steller's or sea cows (Hydrodamalictae, with 1 species - sea ​​cow , exterminated in the 18th century). S. are adapted to an aquatic lifestyle; do not come out on land. Their torpedo-shaped body ends with a solid or two-lobed caudal fin, which serves as the main organ of movement. The head is bluntly cut, the neck is short, but mobile. The forelimbs in the form of massive flippers are movable at the elbow joint and wrist joint. The skin is rough, dark brown in color, with occasional sparse hair. The subcutaneous fat layer is thick. Paired nostrils are located at the end of the muzzle. In the thoracic region - a pair of mammary glands. The teeth and digestive organs are adapted to feeding on aquatic plants. Modern S. have from 2 to 8 simultaneously functioning molars in each half of the jaws. Male dugongs have a pair of incisors in the upper jaw, resembling small tusks. During the life of S. is replaced by up to 30 molars. In a sea cow, the palate and lower jaw were covered with horny plates. The stomach is voluminous, from 2 departments; the intestine is long, with a developed caecum. S. are rare everywhere. They keep in small groups. Cub 1, pregnancy in manatees lasts 5‒6 months, in dugongs - 11 months. The number is declining everywhere, so S. need protection.

Lit.: Mammals of the Soviet Union, ed. V. G. Geptner and N. P. Naumov, vol. 2, part 1, M., 1967.

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    Official terminology

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"Sirens (Squad of Aquatic Mammals)" in books

author Bram Alfred Edmund

Order XII Herbivorous whales, or sirens

From the book Animal Life Volume I Mammals author Bram Alfred Edmund

Order XII Herbivorous whales, or sirens In terms of the internal structure of the body, these animals most likely resemble ungulates, only adapted to permanent life in the water. The distinguishing features of the sirens are: a small head, clearly separated from the body, with bristly,

Sirens of Colmar

From the book Dolphin Man by Mayol Jacques

Sirens of Colmar I remember a few years ago, traveling through Alsace, in the Museum of Colmar, I stopped in front of a skillfully made wooden figure of a sirenoid, or water man, a work of the 14th century. Strange thing, this sirenoid was not a newt, a sea creature,

AFTER THE SIREN

From the book Hundredth Chance author Sturikov Nikolai Andreevich

AFTER THE SIREN He expected Siren to rise dressed in a prisoner's robe - he must quickly hide in the seething, running crowd, evade a meeting with punishers and warders. And dived into the middle of the human stream. He took it out to the washbasin. And here he saw through the window ... I saw it on

Sirens

From the book Encyclopedia of Slavic Culture, Writing and Mythology author Kononenko Alexey Anatolievich

Sirens These mythical creatures are known from Greek mythology. Sirens are the daughters of the lord of fresh waters, the god Aheloy, and one of the muses (Terpsichore or Melpomene). They inherited a wild and evil character from their father, a divine voice from their mother. Their bird feet

SIRENS

From the book Exotic Zoology author Nepomniachtchi Nikolai Nikolaevich

SIRENS Sirens are mythical female creatures, female birds or mermaids, who lure sailors and destroy them with their singing and enchanting music. Sirens came to us from ancient Greek mythology, mainly from the legends of Jason and Odysseus (Ulysses, in Latin). Jason and

Sirens

From the book The Complete Encyclopedia of Mythological Creatures. History. Origin. magical properties by Conway Deanna

Sirens Despite the fact that in Greek mythology the sirens were associated with the ocean and water, they were originally birds with human features. Their name comes from a Greek root word meaning "to bind or bind". In Latin, this word came as sirena,

Sirens

From the book Mythological Dictionary author Archer Vadim

Sirens (Greek) - half-woman half-birds, born by the river Aheloy and one of the muses (options: Melpomene, Terpsichore) or the daughter of Sterope. The number of S. ranges from two or three to many. S. live on a rocky island, the shores of which are strewn with the bones of their victims, lying between Kirki Island

Sirens

From the book Encyclopedic Dictionary (C) author Brockhaus F. A.

Sirens Sirens (SeirhneV, Sirenes) - in Greek mythology, sea muses, personifying a deceptive, but charming sea surface, under which sharp cliffs or shallows are hidden. The first mention of S. are in the Odyssey. They live in the west, on an island between the earth

Sirens

From the book Disasters of the body [Influence of stars, deformation of the skull, giants, dwarfs, fat men, hairies, freaks ...] author Kudryashov Viktor Evgenievich

Sirens Sirens personify both danger and irresistible charm. Legends say that at night these beautiful creatures call on sailors to return to the sea. Unfortunately, the term "siren" is of little use for the unfortunate creatures that medicine

Sirens (order of aquatic mammals)

From the book Great Soviet Encyclopedia (SI) of the author TSB

Sirens

From the book No Gold in the Gray Mountains [compilation] author Sapkowski Andrzej

Sirens In Greek mythology, they were considered the daughters of the river deity Aheloy and one of the muses (either Melpomene, or Terpsichore). They were Persephone's playmates, and as punishment for not preventing Hades from kidnapping her, they were turned into monsters: half-woman, half-fish. They are ordered

Sirens

From the book Encyclopedia of Classical Greco-Roman Mythology author Obnorsky V.

Sirens In ancient Greek mythology, sirens are the characters of fantastic sea tales. Melodious singing and omniscience bring them closer to the muses. They are considered the children of Achelous, or, as some believe, of Phorcias and the Muses of Terpsichore, or the daughter of Portaon, named Steropa. They have faces

Sirens

From the book Myths of Greece and Rome author Gerber Helen

The Sirens Having finished this business, the Greeks, driven by a fresh wind, left the island of Circe and sailed on until they reached the rocky island where the Sirens lived. They sat on the rocks and sang their magical songs that made the sailors turn off course and swim towards them.

150. Two Sirens

From the book of Proverbs and History, Volume 1 author Baba Sri Sathya Sai

150. Two sirens There are two insidious sirens who seduce the youth with vanity and licentiousness, dragging them onto the path of destruction. One of them is Ms. Cinematography, the other is Ms. Fiction. Most films desecrate and corrupt young, innocent minds, they teach

A huge number of living beings live on our planet, surprising with their species and forms. Among them there is an interesting and unique animal - a mammal siren that lives in sea and fresh waters. It is represented by several types, different in their characteristics.

Description

Examining the fossil remains of animals, scientists came to the conclusion that the ancestors of the sirens lived in shallow water. They had four limbs, went to land and ate grass. The number of remains of animals like sirens speaks of their large population.

In the course of evolution, the hind limbs of these mammals disappeared and a fin appeared instead.

Thanks to modern technology, seeing a photo of a siren is quite simple.

These amazing mammals have a very cautious nature. They never leave the expanses of water, so it is impossible to meet them on land. Move slowly and smoothly.

They live in small families or one by one. Life expectancy is about 20 years.

habitats

Mammals sirens are adapted to life only in water. Mostly choose warm shallow water. Depending on the species, they live in both salty and fresh waters. Distributed in the waters of the Amazon River, the Indian Ocean, along the Atlantic coast of America, the western coast of Africa, near the Caribbean islands, the waters of Brazil and some other countries.

Characteristic

The body of the sirens has a very interesting structure, shaped like a cylinder. The length can be from 2.5 meters to 6 meters. Body weight reaches 650 kilograms.

The bones of animal sirens are heavy and have a dense structure. In the course of evolution, fins were formed from the tail and forelimbs.

The forelimbs are shaped like flippers. Very mobile in the elbow and wrist joint. Five fingers are distinguished on the skeleton of the animal, but it is impossible to detect them in appearance, since they are covered with one skin and form a fin.

The hind limbs gradually disappeared. Now they cannot be seen even in the structure of the skeleton of these mammals. Sirens also lack a dorsal fin.

The back fin has no rounded bones. It is necessary for the implementation of the motor function and navigation.

The skin has sparse hairs resembling bristles. The skin forms folds on the body, its thickness is quite large. Under the skin is a well-developed layer of adipose tissue.

The head is elongated, rounded, with small eyes, nostrils and mouth. There are whiskers on the head, which, together with a developed upper lip, perform a tactile function and help the siren explore objects. The animal does not have auricles. Auditory openings are relatively small. The number of teeth depends on the type and age of the animal. The small and short tongue is calloused in structure.

Classification

Siren mammals today are divided into two families.

Dugons. The only representative of the family living in our time is the dugong. The average body length is from 2 to 4 meters, weight up to 600 kilograms. The largest number of individuals inhabits the Great Barrier Reef. They live in warm shallow water, often alone. There are known cases of dugongs entering the sea and estuaries. Among the striking differences from other sirens is the presence of a tail, divided by a recess into two parts. And also has larger and more elongated lips.

Extinct representatives of the dugong family are sea cows. They differed in large sizes: the length reached 10 meters, the weight was up to 10 tons. They lived in the waters of the Pacific Ocean in shallow water, without sinking too deep. They led a herd life, had a calm character.

Manatees. They are divided into four types:

  • American manatee. The average body length is 3 meters, weight is from 200 to 600 kilograms, and females are usually larger than males. They live in small swampy areas of the Caribbean Sea in the region of South, Central and North America; in places rich in abundant vegetation suitable for food, without the presence of enemies among other animals. Since it has a small layer of fatty tissue, it prefers only warm water. It has a gray color with a blue tint. The American manatee is able to take root in both salt and fresh water, adapt to a polluted environment.
  • Amazonian manatee. Habitat is typical only for the waters of the Amazon River. Does not survive in salt water. Prefers deep and still waters. The color is distinguished by smoother skin, the presence of one or more white spots on the chest. It has small dimensions: average length is 2.5 meters, weight is 400 kilograms. The most dangerous natural enemies are crocodiles and jaguars.

Below is a photo of an Amazonian manatee siren.

  • African manatee. Distributed in coastal waters, rivers and lakes along the western coast of Africa. Avoids waters with high salinity. The characteristics are very similar to the American manatee. The main difference is the black and gray color of the skin. It is most active at night.
  • Dwarf manatee. Little is known about the life of this species. It lives in the rivers of the Amazon basin, choosing areas with fast water movement. Among the sirens, it has the smallest dimensions. The average body length is only 130 centimeters, weight 60 kilograms. The color of the skin is black with a white spot on the chest, like that of the Amazonian manatee.

Nutrition

Sirens are herbivores. Since they never go to land, they feed on sea grass and algae that grow at the bottom of the reservoir. The upper lip is well developed, which allows it to successfully grab and pluck plants.

Fruits and leaves of trees that have fallen or hanging low to the water also serve as a source of food for some species.

In some cases, sirens can eat fish and invertebrates. This usually happens when there is a lack of plant foods. Also, with a limited amount of algae and grass, these animals migrate in search of places rich in suitable food.

Behavior

Mammals sirens have a very calm and slow nature.

Individuals communicate with each other with the help of which they notify of possible danger, serve as a means of communication between the female and the cub, or are a call during the breeding season.

The body of the sirens is arranged in such a way that it is easy to confuse the animals with bathing people. Perhaps this was the reason for the unusual name of mammals, taken from Greek mythology. The Song of the Sirens is also related to creatures from fairy tales. And it doesn't apply to mammals. Animals make sounds that are more like crackling than the singing of sirens from mythology.

When threatened by predators, they often flee.

Mostly lead a solitary lifestyle. Sometimes they can gather in small groups in places rich in marine vegetation.

They do not descend to great depths, as they emerge from the water every 3-5 minutes to breathe.

reproduction

The breeding season is not tied to a specific time, it occurs throughout the year. At this time, females secrete a special enzyme. They also call on males with characteristic sounds. Males can be aggressive towards each other due to the attention of the female.

The siren's pregnancy lasts a little over a year. Births take place in shallow waters. As a rule, one cub is born (two - very rarely) weighing from 20 to 30 kilograms and about one meter long. Feeding is quite long, from a year to a year and a half, despite the fact that the cub is able to eat plant foods at about three months.

The relationship between a female and her cub is long-lasting and especially affectionate. Males do not take part in the development of offspring.

Sources of threat to life

Unfortunately, today these amazing mammals are endangered. The reason for this was the hunt for valuable meat and the skin of this animal, as well as damage received from the movement of the blades of the engines of ships and boats. It is not uncommon for sirens to get caught in fishing nets.

Environmental pollution also contributes to a significant decrease in the number of these animals.

Mammals sirens have enemies in their natural environment. These are sharks, crocodiles and jaguars.

Genus: Trichechus = Manatees

Species: Trichechus bernhardi Roosmalen, 2007 = Pygmy manatee

Species: Trichechus inunguis Natterer, 1883 = Amazonian manatee

Species: Trichechus manatus Linnaeus, 1758 = American manatee

Species: Trichechus senegalensis Link, 1795 = African manatee

Brief description of the detachment

Sirens are secondary aquatic mammals (marine or freshwater) that have adapted to permanent life in the water.; close to ancient ungulates. Body length 2.5-5.8 m (for an extinct sea cow up to 7.2-10 m). Weight up to 650 kg (for a sea cow up to 4 tons).
Body massive fusiform. The neck is short and thick, but mobile. The head is relatively small, rounded with a relatively small mouth. A strongly developed upper lip forms a soft "lip disc" - a kind of trunk, equipped with organs of tactile sensation. The mouth opening is located on the lower surface of the head. External nasal openings open at the top of the head and are able to close. The eyes are small, with movable eyelids without eyelashes; the nictitating membrane is well developed. There are no auricles, the ear openings are very small. The forelimbs are five-fingered, turned into flippers. The hind limbs are reduced. The flippers move freely in the shoulder joint and, unlike cetaceans, are mobile in the elbow and wrist joints. The fingers are dressed in a common skin and are invisible from the outside. Skeletonless horizontal caudal fin triangular or rounded; it serves as a locomotor organ. Leather thick, covered with sparse bristly hairs. Subcutaneous adipose tissue is highly developed. Numerous thick vibrissae are located on the lips. Two nipples are located in the chest area. Molar teeth with a flat chewing surface, as in ungulates; the stomach consists of several sections.
The stomach is complex. The intestine is very long. It exceeds the body length by 13-20 times. The lungs are simple, long and narrow, not divided into lobes. The brain is small with few convolutions; olfactory lobes are well developed. feed on underwater vegetation, keep in herds, grazing on underwater "meadows".
common sirens in the tropical waters of the Indian, Atlantic and Eastern Pacific Oceans, as well as in the basins of the Amazon, Orinoco, and in the rivers of tropical West Africa. An extinct sea cow lived in the Bering Sea. Sirens are hunted by the locals for their delicious meat and tough skin.
fossil representatives orders are known from the Middle Eocene of ARE and Jamaica. The most ancient of them, although they had a number of primitive features (a complete dental system, the absence of horny plates, a rather well-developed pelvis, rudimentary hind limbs), were real aquatic animals. In the structure of their skull and teeth, there is a resemblance to primitive proboscis and hyraxes. Apparently, the ancestors of the sirens were land animals close to the original forms of proboscis, hyraxes and ungulates.
The manatee family Manatidae- 3 species - lives off the coast of West Africa and east of South America (near the Antilles). In the dugong family Halicoridae one species distributed in the coastal strip of the Indian Ocean. In 1741, the zoologist Steller discovered a Steller's cow near the Commander Islands - Rhytina Stelleri. Exterminated by hunters: the last copy was killed in 1768

Sirens are the third largest taxon of aquatic mammals. Unlike seals, however, they cannot move on land due to the weakness of their limbs. They cannot be compared to whales either, as they usually live in shallow coastal waters or even fresh water.

Sirens are massive animals with a cylindrical body. Their forelimbs turned into fins, and the hind limbs completely disappeared during evolution, their remains cannot be established even in the skeleton. Sirens do not have a dorsal fin, like some species of whales. The tail has changed into a flat rear fin. The skin is very thick and wrinkled, there is no hairline. The muzzle is long, but flattened, not pointed. She is surrounded by hard and sensitive whiskers, with which the sirens touch objects. The nostrils are relatively high. The volume of the lungs is regulated independently of each other, which allows you to shift the center of gravity and increases stability. Compared to the body, the head is quite large, however, the volume of the brain in relation to the size of the body is one of the smallest among all mammals. The number and shape of teeth in individual genera of sirens varies greatly. The incisors are often found in a degenerate form, and canine teeth are absent in all extant species. The front of the palate is covered with calloused layers, which probably aids in eating. The short tongue is also calloused.

Sirens live alone or in small groups. They always move slowly and carefully. Their food is exclusively vegetarian in nature and consists of seagrass and algae. Since the molars are constantly abraded by the sand that has settled on the algae eaten, teeth that grow deeper in the mouth take the place of the worn teeth. The life expectancy of sirens is about twenty years.

Evolution

Sirens have common land ancestors with proboscis and hyraxes. The earliest known fossils of siren-like animals date from the early Eocene and are about 50 million years old. These animals were tetrapods and herbivores, still able to move on land, but already living mainly in shallow water. Subsequently, the ancestors of the sirens were very successful and widespread animals, as evidenced by numerous fossilized remains. The hind limbs disappeared fairly quickly, with a horizontal hind fin developing instead.

Families formed in the Eocene Prorastomidae († ), Protosirenidae(† ) and dugongs ( Dugongidae). According to the opinion prevailing among zoologists, manatees appeared only in the Miocene. There were no traces of the first two families already in the Oligocene, since then the order of sirens has been divided into only two families. In the Miocene and Pliocene, sirens were much more numerous and diverse than they are today. It is likely that the changes in climate that occurred during the Pleistocene significantly reduced the squad of sirens.

Systematics

The two families of sirens are:

  • dugong ( Dugongidae) consists of a single living species - dugongs. About 250 years ago, there was another species - Steller's cow, which is now extinct.
  • Manatees ( Trichechiidae) - contains three types:
    • African manatee ( Trichechus senegalensis)
    • Amazonian manatee ( Trichechus inunguis)
    • American manatee ( Trichechus manatus)
    • Pygmy manatee ( Trichechus bernhardi)

Sirens and people

The name of the sirens comes from the sirens from Greek mythology, since from a distance they are easily confused with bathing people. However, the singing of the legendary sirens does not suit these animals in any way. Although Christopher Columbus was not the first person to see sirens, it is known that he mentioned them in his diary in 1493.

All modern types of sirens are considered endangered. The main danger for them is motor boats, which, with their propellers, seriously cripple these shallow-water-loving animals. Another threat is human destruction of the environment and penetration into their traditional habitats. Due to their metabolism, sirens need a lot of algae, and their presence is directly related to water quality, which is increasingly falling due to human influence.

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