Methods for protecting animal organisms. Protecting animals from predators

Meeting with natural enemy usually ends in the death of the animal, therefore, in the process of evolution, only individuals with effective methods of defense survived. How do animals protect themselves from enemies, what protective devices have they acquired in the struggle for survival?

Animals defend themselves in different ways. Some quickly run away, others skillfully hide or disguise themselves, and others defend themselves. It all depends on the size of the animal, its lifestyle and the protective organs that Mother Nature has endowed it with. Below are the most interesting methods of protection.

How animals defend themselves when running away from enemies

The hare, running away, reaches speeds of up to 70 km/h, but this is not a record. Saigas, gazelles and antelopes are capable of fleeing danger at a speed of 80 km/h. Moreover, some animals are capable of making ultra-long jumps while running: for example, a roe deer is up to six meters long, and an impala antelope is up to 11 meters long and up to 3 meters high.

How animals protect themselves by hiding from enemies

A hole is the most reliable shelter of an animal, but some animals, such as a fox or a beaver, “guessed” that it was better if there were two exits from it, distant from each other. And the beaver’s entrance and exit to its “hut” are completely underwater.

The same applies to seemingly open shelters such as bird nests. This is how the Cayenne swift builds a tube-shaped nest. One hole in such a nest is a wide and noticeable, but dead-end “entrance” for “strangers,” and the second is a small and inconspicuous entrance for the swift itself.

How animals protect themselves by camouflage

The true masters of camouflage are insects. So even the sharp eyes of birds cannot distinguish a praying mantis sitting on a bush or tree from a twig or leaf. Some insects even imitate the vibrations of plants from the wind with their body movements.

The coloring of the surface of the body of many animals coincides with the primary colors of their usual habitat; it is, as they say, protective. It is for the purpose of camouflage that the seasonal molt some animals living in the northern hemisphere, such as hares.

How animals protect themselves by defending themselves

Animals defend themselves with whatever they can: with teeth, claws (wolves, cats, bears), horns, hooves (elk, deer), quills (hedgehogs, porcupines) and even tails ( sea cat). But especially interesting are animals that use the substances produced by their bodies for protection. chemicals.

An ordinary ladybug, when attacked or frightened, releases many droplets of an unpleasant-smelling bright yellow liquid called quinenone. Birds do not like the smell of quinenone; they mistake it for poison and, ladybug, they immediately release her.

When in danger, southern bombardier beetles secrete a liquid that instantly evaporates in air with a slight “explosion,” forming a cloud. The beetle is capable of performing this “trick” several times in a row, and a series of such unexpected “explosions” very often scares away enemies.

Some types of cobras (Indian spitting, African black-necked and collared) defend themselves by “spitting” venom into the eyes of the enemy as a sniper. Moreover, the black-necked cobra can perform this operation up to twenty times in a row.

How does a skunk protect itself from enemies?

The legendary animal that defends itself using chemical secretions is the North American skunk. In defense, he turns his back to the attacker, raises his tail and pours very unpleasant-smelling secretions of the anal glands on the enemy.

These secretions literally repel the aggressor with their smell and, once on any surface, retain their smell for a very long time. North American motorists have been unable to wash their damaged vehicles for several months. chemical attack skunk car.

Some animals defend themselves from enemies by taking on a threatening appearance, leaving parts of their body in the paws of the attacker, or even pretending to be dead. There are many methods of protection, and their effectiveness can be evidenced by the fact that the representative of the fauna using them has not yet disappeared from the lists of the animal world of our planet.

found in North America Western Europe and the USSR.

A predator is an animal that kills other animals and feeds on them, and its actions themselves are called predation. Domestic cats are also predators; they catch mice; The life of predators is a cat-and-mouse game known throughout the world, it is repeated constantly and everywhere in ecosystems, millions of animals participate in it, each in its own way.

Lions, pumas, wolves, eagles, hawks, herons, crocodiles, sharks, pikes are undisputed predators. Toads and frogs are also predators, although not as obvious. Predators and everything insectivorous birds. And tiny shrews. And a wasp carrying a caterpillar to its larva. And water beetle larvae sucking a tadpole. And the tadpole itself. Even a whale that feeds on marine zooplankton is a predator. Man is no exception, a universal predator, possessing cunning, dexterity, and the greatest destructive power.

Production range.

There is an upper limit to the size of prey - a predator cannot cope with very large animals; and the lower limit - there is no point in hunting small fry or spending time and effort on them. Between these limits lies the predator's prey range. A predator may be tempted by game of inappropriate size only during periods of hunger, when there are very few animals in its range. Thus, European buzzards and golden eagles feed on the chicks of small songbirds when hares, rabbits, partridges and voles (their usual prey) become very scarce.

It happens that a predator hunts only one species from its prey range for some time: when this species has multiplied greatly and has become easily accessible. For example, white storks that follow swarms of locusts in Africa; skuas hunting lemmings in Alaska; short-eared owls that settle in areas where voles are infested, or herons and otters that feed exclusively on frogs during their mass emergence from ponds at the end of summer.

Chicks harrier in a defensive position. Defending themselves from the enemy, they fall on their backs and fight off with their clawed paws.

Doesn't the predator get tired of the food that is available in abundance, which it feeds on day after day? Watching the European tit, you come to the conclusion that it is annoying. This bird, similar to the North American chickadee, was studied by Luke Tinbergen in pine forests Holland while feeding chicks. Various caterpillars served as food for these tits. When the caterpillars had just appeared, the tits did not eat them very willingly for the first few days. Then they suddenly attacked them greedily. Tinbergen decided that tits gradually developed a specific visual image of new prey. Simply put, their eyes were getting used to the sight of new food. There were more and more caterpillars, and then the appetite of the tits began to weaken, as if this food had become boring to them. Since then, any type of caterpillar has made up only half of the tit's diet. This observation shows that tits prefer mixed food, even if it takes more work and time to find it.

In the case described above, the tits had so much food that they could be picky. But in general, it is difficult for tits, wagtails and our other birds to feed their chicks. Parents have to fly up to the nest almost every minute, and they cannot start large families if there is no abundant food near the nest. The predator does not always go and kill the game as soon as he gets hungry. Sometimes he will be lucky, and sometimes not.

Hard and easy ways.

Not all predators are equally dexterous and agile. One male short-eared owl will miss fourteen times before he dries, another will miss only four. Some crows in a nesting flock perform parental duties much better than their relatives: they are the best breadwinners, that is, the best hunters and the best providers.

hunts mainly lowland animals: antelopes and zebras. A lion with several relatives forms a family called a “pride”. Lionesses, unlike lions, do not have a mane; they are smaller and more graceful.

The predator's mistakes and failures can be explained by his youth and inexperience. But we must also take into account the sensitivity of the prey, because sensitivity in prey animals is as important a property as swiftness in predators. Even for an experienced, adult predator, life is not at all so simple, and he may miss or fail to catch up with the victim, especially if the victim has a wealth of life experience. A fox may be left with a handful of feathers in its mouth instead of a bird, or with the wriggling tail of an escaping lizard. Lions often do not kill large ungulates, but only wound them. Many adult salmon caught by fishermen show signs of teeth or claws. This means that salmon once managed to escape from the mouth of a predator - a seal.

Why did the predator kill this particular animal this time and not some other animal? The short answer is: it just happened. A prey of suitable size appeared at the right moment in an accessible place and fell into the predator’s paws. Not only the presence of the victim is necessary - it must be reachable. This depends on many things: the animal’s ability to camouflage, its age, state of health, speed of legs and its position in the group. Other factors that apply individually to the predator also play a role; firstly, the weather: rain, frost, deep snow, wind strength and direction; then sounds: the noise of a forest, a nearby river or waterfall; as well as the predator's ability to withstand competition.

loves to build nests under the shade of hedges and in dense bushes.

What does sacrifice taste like? main factor, it plays a role only if the predator has a very real choice. The fox, apparently, prefers pheasant to rat, but she will not scour half the night in search of a delicacy when rats are swarming under her feet. Sometimes a predator kills an animal that is not at all to his taste: in the heat of the hunt, he mistakes the pursued game for something he would gladly eat. A cat, for example, kills shrews, but does not eat them. She apparently mistakes them for mice and discovers the mistake when it is too late. Shrews, having once made a mistake, do not repeat the mistake again and do not kill “tasteless” game, remembering its smell. No one knows how often mammals make such mistakes and how quickly they learn to recognize inedible animals. Shrews are generally inedible due to their unpleasant odor to all mammals, although some will eat them if nothing else is available. But what is poison for one person, the proverb says, is honey for another. Hawks and owls will not miss the opportunity to catch a shrew and eat it with pleasure.

A predator that feeds on a particular species encounters individuals of that species in a wide variety of situations. A pursued animal can run into a thicket, where it is not visible, or, conversely, into open forest, where it is more difficult to hide and where it is within greater reach of a predator. It is easier for an experienced adult animal to escape from a pursuer than for a young and inexperienced animal, because an adult animal knows better the tactics of the pursuer, the terrain and possible ways to escape.

Very young and very old, maimed by predators, sick or hungry are easier prey than healthy animals in full bloom. An important factor is the position of the animal in the group: among the animals there are their own parties, they graze on the worst pastures, where there is little food and there is no good shelter from enemies. The age and experience of the predator, that is, the speed of its legs and cunning, also matter.

These factors play a role wherever there is a predator-prey relationship, but in different situations one or another factor or even a group of factors can become of great importance.

Prey selection.

What all situations have in common: the predator attacks the one who is easier to grab at the moment. If there are two species of prey animals and both are equally accessible, the predator hunts both species, and the number of victims will be proportional to the number of animals of each species. If one species is easier to hunt, the predator will prefer that species until the situation changes. A good example of this is the Scottish marten. She subsists on voles and wood mice; voles suffer from it more than forest mice, although there are fewer voles on its territory. Wood mice were caught in the traps placed there more often, which means it was easier for the marten to catch voles. This may be explained by the fact that wood mice are more careful, they run and jump well, while voles are slow and not so nimble.

The European mole is another example of such selectivity. Moles feed mainly on earthworms. When there are a lot of worms, the mole catches them in abundance, cripples them and stores them for future use. Such mole warehouses have been studied many times; As a rule, one species of earthworm predominates in them, although a large number of other species of earthworms are found on its lands. Why this happens is still unknown. It can be assumed that the mole stores the type of worm that is easier to catch.

on the hunt. A wolf pack usually includes a male, a female, wolf cubs, and sometimes two or three more wolves join them.

Predators also choose within a given species, and do not rush in pursuit of the first animal they come across. North American wolves, hot on the heels of caribou herds, kill calves, old deer, sick and wounded animals. The Zambian hyena dog hunts hartebeest antelopes, but is very selective. Most of all, it kills calves that are less than a year old; There are slightly fewer yearlings, even fewer old animals, and very few healthy adults. Lions kill age groups in proportion to their numbers in the herd - also a kind of selectivity. Hyenas hunting antelope in the Serengeti kill only calves - another form of selectivity.

The European sparrowhawk and peregrine falcon, as observations have shown, often kill those birds that stand out from the flock in some way. Five of the twenty-three birds killed by the hawk turned out to be some kind of deviation from the norm. One day, a sparrowhawk snatched a lame blue tit from a flock of twenty-six healthy tits. In Germany it was recorded: out of seventeen domestic pigeons caught by a peregrine falcon, fifteen were either somehow different from other pigeons or were strangers in the flock. In Poland, a hawk was seen snatching a white dove from a flock of doves and a dove from a flock of whites.

Rivalry.

Man, bystander and predator himself (addition from the site: if this person the owner of an animal-type psyche, which is a violation, because after all, Man is predestined from above to have a different type of psyche, different from that of an animal) , is inclined to consider wild predators who hunt game that he himself needs as his rivals. General hostility to predators (addition from the site: among the “humanoid predators”) is explained precisely by this; the above examples, the number of which can be multiplied, show that such an attitude towards predators is hardly fair. As a rule, it is not the quantity of game that depends on the number of predators, but vice versa. A loaf of bread can only feed a certain number of mouths.

Partridge numbers have fallen sharply in Scotland in recent years. This phenomenon has been studied and interesting findings regarding predation have been obtained; the most important: predators are not to blame for the disappearance of the Scotch partridge, the reason for this is the behavior of the partridges.

valuable game birds. It is found on heather heaths and mountain slopes. The partridge needs dense, well-leafed heather both for food and for shelter. The most aggressive male takes over the best territory. Humans artificially maintain the habitat necessary for partridges by periodically burning out old heather.

A bird living in a certain area; it feeds on heather, lives and breeds on heather heaths. The male owns a certain territory, which he defends from other males. The most aggressive males have the best territories, the less aggressive ones have worse territories, and so on; eventually all the land is divided between the married couples. Birds that were unable to capture any territory become “outcasts”, contenting themselves with the worst marginal lands: bare slopes, floodplain meadows, areas with poor cover, where there is little food and it is difficult to hide from enemies. These outcasts are six times more likely to become victims of predators, and many die from starvation or disease. Some move to other places in search of territory; the number of eaters is decreasing, and now the heathland can feed everyone. An ecologist would say that this competition for territory is a kind of buffer between the bird population and the amount of food.

In August, partridge hunting begins, and the entire system of dividing territories is disrupted. Young broods are equally threatened by wild predators and humans. Human predation causes great damage to the partridge population, although humans do not always exterminate the entire annual offspring, that is, they do not kill as much as they could. And in the fall, when the birds re-divide the territory, outcasts again remain, for whom no good land was found.

Once again, wild predators kill many more outcasts. And again, many die, and many go to other places. Some people still remain, taking advantage of the territory, which for one reason or another found itself without an owner. Scottish partridges regulate their population themselves, and a careful approach to heather lands does not require the extermination of predators, but concern for the protection of vegetation.

"Fixed capital" and interest on it.

The predator feeds on its victims without reducing their numbers: it regulates their numbers. The predator lives, so to speak, not at the expense of fixed capital, but at the expense of interest on this capital. A mole, which feeds almost exclusively on earthworms, does not have any noticeable effect on the number of worms living in its territory. And the stoat, which hunted rabbits while they were found in Europe, did not pose a threat to the population of these rodents. The barn owl, which lives in Palestine, in the Levant, has half its diet made up of voles: the number of all voles eaten, however, is relatively small; barn owls not only do not touch the “fixed capital”, which is a population of 25,000 voles, but they hardly even spend the interest on the capital. In the same way, all the cats in the world cannot do anything about the mouse population, which is still prosperous to this day.

Owl hunts all night, from dawn to dusk; its food is small rodents: voles, mice, rat pups. It happens that an owl will catch and eat a small bird. Owls do not build nests; they live in hollows and abandoned nests of other birds: crows, magpies or kestrels.

And yet it happens that small predator causes serious damage to the population of its prey. A tiny weasel, for example, has access to the holes of mice and voles, and, once in such a hole, it can cause real devastation among its inhabitants. Americans McCabe and Blanchard report that weasels, finding themselves in an area where there were many deer mice, walked through their burrows and destroyed almost all of the mice.

Insectivorous birds can sometimes delay the reproduction of insects, but in the case of European tits, described by Tenbergen, the birds of prey ate most of the caterpillars when there were not so many of them. Birds, as a rule, cannot cope with hordes of insects. The fact that birds at some stage can inhibit the reproduction of insects is very important for humans. In Germany, this has long been understood; there are small houses everywhere in the forests, like birdhouses, in which tits make their nests. Feathered lodgers help people to protect the forest - biological protection instead of chemical.

What about large predators? Do they control big game populations? In some cases there is no doubt, as evidenced by the facts, albeit still few. A striking illustration of this is the history of the black-tailed deer that live on the Kaibab Plateau. At the beginning of the 20th century in Arizona, a herd of black-tailed deer numbering 4,000 heads lived on the Kaibab Plateau. They shared this habitat with predators: wolves, cougars, coyotes, lynx and a few bears. Herds of domestic animals - sheep and cattle - also grazed here. The deer population did not grow or decrease under these conditions, remaining from year to year within 4,000 heads. This area, however, could support a much larger herd of deer; No one had any doubts: predators were to blame for the low number of deer. And in 1906 the territory was declared state reserve. To increase pasture for deer, livestock grazing was prohibited; Hunters were invited to fight predators. Over the course of a decade, 600 pumas were shot. In sixteen years, 3,000 coyotes were exterminated. By 1926, wolves were completely destroyed. The number of deer began to grow, at first slowly, then faster , by 1920 the deer herd had grown to 60,000 head, and by 1924 to 100,000 head. This monstrous figure turned out to be fatal. The plateau could not support so many black-tailed deer. They multiplied threateningly and completely trampled the pastures. Over the next two winters, 60,000 deer died. By 1929, the number of deer had dropped to 30,000, by 1931 to 20,000. And in 1939, only 10,000 black-tailed deer grazed the Kaibab Plateau.

This is a cautionary tale. The predators were obviously holding back deer population growth , thereby protecting natural pastures. The destruction of predators led to the fact that deer multiplied catastrophically and destroyed the pastures on which they fed.

The same balance exists in nature between lions and the topi antelope, which lives in the Ruin di Rutshuru valley in the former Belgian Congo. From 1918 to 1929, lion hunting in the area was particularly intense; quantity large predators sharply decreased, and the number of topi antelopes, as one would expect, increased greatly.

Close relatives.

Competition between predators various types living in the same territory is more apparent than real, even if several species hunt the same animals periodically or constantly. Changes in habitat, or in the number or proportion of animals that predators eat, can tip the balance in favor of one predator or another. Some predators benefit from this, while others suffer.

(lat. Mustela erminea) - small predatory animal family of mustelids, typical musteloid appearance with long body on short legs, a long neck and a triangular head with small rounded ears. The body length of the male is 17-38 cm (females are about half as long), the length of the tail is about 35% of the body length - 6-12 cm; body weight - from 70 to 260 g. Similar to weasel, but slightly larger in size.

These relationships have been well studied in the case of weasels and stoats living in the Northern Hemisphere. In England, weasels and stoats often live side by side in the same territory; and as long as each species hunts its prey, there is no rivalry between them. Weasels are much smaller than stoats, a male weasel weighs only 150 grams, and a male stoat weighs 350 grams. If there are a lot of rabbits, the ermine hunts mainly on them, while weasels hunt voles. In such a situation, both predators prosper. If the rabbits are affected by myxomatosis, which kills these rodents without exception, the number of stoats decreases noticeably, but this does not affect the weasels at all. The disappearance of food disrupts the balance of the ecosystem to the detriment of the stoat, without affecting the weasels.

Young forest plantations Temperate countries are an ideal habitat for voles, which are very fond of thickets of thick, tall grasses. In such a biocenosis, both weasels and stoats feed on voles. The relationships of these animals have been well studied in Scotland. The weasel, due to its diminutive size, can hunt voles underground, in their burrows. An ermine will not fit into a mouse hole and is content with random prey, that is, those voles that it catches on the surface. The weasel also has access to its main capital: by destroying voles underground, the weasel reduces the amount of random stoat prey; but as long as the number of voles does not fall below a certain critical figure, both predators are not afraid of hunger. However, the number of voles is subject to sharp fluctuations, and if there are fewer than forty-five per acre, the stoats leave their homes. Weasels continue to exist carefree in this territory until the number of voles drops to eighteen per acre. With the departure of the stoats, the number of voles begins to increase. Eventually there are so many of them that the stoats return again.

, or common weasel (lat. Mustela nivalis) - carnivorous mammal family mustelids, species of the genus Weasels and ferrets (Mustela). Found on all continents of the Northern Hemisphere.

Here is another example of the coexistence of weasels and stoats, this time brought to the Dutch island of Terschelling. On this island, in the early 1930s, water voles began to cause great damage to the forest. They decided to use biological protection of the forest and in 1931, 102 weasels and 9 stoats were brought to the island. Three years later, there were no weasels left on the island. Five years later, the stoats completely destroyed the water voles and sharply reduced the number of rabbits living on the island. Now it was necessary to take urgent measures against the stoats, which quickly multiplied and began to prey on all kinds of birds: wild, domestic and even waterfowl. Natural balance was achieved only in 1939. Stoats remain on the island, but are no longer a problem. In this case, the stoats found themselves in an advantageous position, and the weasels, unable to withstand the competition, died.

The USA has its own weasels and its own stoats; The American weasel is no different from the European one, but the American ermine, unlike the European one, can be a very small animal or a larger one: different types of ermine live in different regions of the country. The largest is distributed in the USA in the eastern and northwestern regions up to Alaska. It shares its habitat with the weasel. In the west North America only a small ermine lives, no larger than a weasel; and it turned out that weasels are not found in these places at all. She can live next to large stoats, but cannot stand competition with the “kids”. This example proves that the small variety of stoats is a kind of taboo for affection, it can only live where they are not.

Reference supplement to the book.

Distribution area of the Ermine.

Chapter 9. The rise and fall of a population. Cycles .

Searching for shelters

Most species search for some kind of shelter to hide from sharp fluctuations in temperature, precipitation and predators. Sometimes an animal simply climbs into a cave, crevice or tree, which does not lead to any significant change in the environment. However, in many other cases it builds very complex nests or burrows, which entails significant changes external conditions. Structures can be relatively permanent, such as beaver dams, or temporary, such as chimpanzees' sleeping nests, in which they usually spend only one night. In many species, the structure of the nest is closely related to reproduction: when the time for the appearance of offspring approaches, they begin to build a nest or significantly expand an existing nest.

Among invertebrates, the construction of shelters is most pronounced in insects. In species such as solitary wasps, each individual female digs a burrow and stores food in it. However, in many other species, nests are very complex structures, and entire communities live in them. Examples include tall termite structures and bee nests.

Community structure different types bees are different, but they certainly have one queen and many workers. In the honey bee, a distinctive feature of the activity of worker individuals in building and maintaining the nest is functional specialization. Different individuals are engaged in the construction of combs, feeding the larvae, cleaning the cells, preparing honey, guarding the entrance and collecting pollen and nectar. At the same time, the functions of each individual worker bee change during its life: it begins with cleaning cells and ends with collecting pollen and nectar.

Choosing a place for a new nest for a honey bee is a very interesting process. At the end of spring, the queen and about half of the workers leave the old place for the queen's daughters and form a swarm at a short distance from it. The bees remain in this swarm until a new location is chosen. Scout bees fly out of the swarm to inspect numerous sites that are potentially suitable for nesting. Returning to the swarm, they perform a “dance” containing instructions about where these places are. The intensity of the dance varies depending on the quality of the location. Particular importance is apparently attached to its size and protective capabilities. Dancing bees are recruiting new scouts. Based on the intensity of the dances and the reaction of the new scouts, the swarm “makes a decision”: in the end, the majority of the scouts indicate one specific place with the help of dance, and then the swarm is removed and sent there.

In rodents, behavior associated with finding or building shelter takes very diverse forms. Beavers build single-chamber burrows, or huts, in which a pair of adults and their last two broods live. Tree rats collect many twigs or twigs from which they build extensive huts. The construction of nests by laboratory rats and house mice has been studied in detail. Both species make nests in the shape of cups or bowls, using cotton wool, paper, rags and other similar materials; sometimes the nests are equipped with a roof.

Chimpanzees, orangutans and gorillas build sleeping nests in trees.

Avoiding Predators

Because most species serve as prey for at least several other species, avoiding predators is essential for survival and reproduction. The main methods of protection from predators are hiding from them, warning individuals of one’s own species, the presence of warning signs, flight and active resistance.

Covering

Many animals hide from predators in shelters - holes, crevices and huts. In addition, shelter from a predator can contribute to appearance the animal itself. Protective coloration, thanks to which the animal blends into the background, is found in representatives of almost all taxonomic groups. Many particularly striking examples can be found in insects, which include forms similar to leaves, twigs or even bird droppings. Often protective coloring is combined with special behavior: the animal is positioned in relation to its surroundings in a certain way, usually remaining motionless.

Rice. 4.1. Frequency spectra of calls made by various birds

Warning other animals

Whatever the species-specific response to predators, the prey must first of all be able to detect their presence. Various features of movement, in particular periodic inspections of the area and a certain orientation (for example, in relation to the wind), facilitate the detection of predators. Animals often graze in mixed herds, such as baboons and antelopes. Baboons have very sharp eyesight, and antelopes have a particularly developed sense of smell. Both respond to alarm signals given by individuals of another species, and therefore are difficult to take by surprise.

Many species respond to alarm calls made by birds. As a rule, such calls are relatively pure tones, without sharp breaks; Such sounds are difficult for a predator to localize (Fig. 4.1).

Warning signs or actions

Some animals have an unpleasant taste for predators. If, for example, a blue jay eats a large, brightly colored Danaus plexippus butterfly, it will soon cause vomiting. Such a bright color “warns” the predator that the prey is unfit for food. In the process of evolution, numerous edible species acquired similarities with inedible ones, which gave them an obvious advantage; predators began to avoid them. This phenomenon is known as Batesian mimicry.

A variety of active actions are also used to warn predators. Examples include the sounds made by a rattlesnake and the aggressive postures adopted by many mammals. In birds, the “calling” reaction is well known in relation to stationary predators, such as hawks or owls: birds fly quite close to them, emitting loud cries and performing various kinds of demonstration actions. The sounds produced in this case are characterized by a wide frequency range and clearly defined beginning and end, and therefore are easy to localize (Fig. 4). The advantage that an animal receives by attracting attention to itself is obvious in such cases.

Escape

Speed and agility serve as the best and probably most common means of escape from predators. Many species, when fleeing, supplement their locomotor movements with display behavior in order to distract the attention of a potential predator or frighten it. Others, on the contrary, lie low to reduce the likelihood of an attack.

Active resistance

As a last resort, the victim can offer active resistance to the predator. In this case, it can hit the predator, grab it, or bite it. Skunks and many species of arthropods, such as millipedes, secrete chemicals that repel predators. Other animals defend themselves from predators with thick or poisonous coverings, hard shells, or projections such as spines and spines.

E. Norbert Smith

For many years, it was believed that predators prefer young, weakened or diseased animals as prey. This concept is the basis of the theory of natural selection and one of the dogmas on which the theory of evolution is based. However, this assumption is wrong. the entire superstructure built on natural selection, the driving force of evolution, falls apart if in fact it turns out that predators do not eat the weakest animals. Upon detailed study, it becomes clear that this assumption is not logical and is not confirmed scientific evidence. This means that natural selection cannot be considered as a mechanism of evolution.

Figure 1.. Turtle Terrapene ornata. Photo: Sean Williams.

Natural selection combined with genetic mutations is the basis on which the theory of evolution rests, because it is believed to represent the mechanism by which species can change, adapt and improve over time. Therefore, for more than 150 years, we have all been taught that predators catch weak, young or sick animals, thereby “improving” the genetic pool. Educational programs about nature has been replaced for many people printed publications, and many such programs do nothing but repeat the mantra that predators only attack the weak. We are constantly told that predators perform the most important function - they allow only healthy individuals to survive and reproduce. It is believed that by destroying the weakest, predators contribute to the process of evolution. This “selection of the strongest” is called driving force evolution. If predators do not eat the weakest, then evolution is a theory without a mechanism, an idea without scientific justification. However, does the scientific evidence actually support this scenario?

Animals remain young only for short periods of the year, and most wild animals are healthy. If predators had to eat only young or sick individuals, they would starve to death. There is another big problem with this theory. If predators ate sick animals, it is very likely that they themselves would become sick. This makes common sense and has been known since the time of Moses: “And whoever eats carrion or torn to pieces by wild beasts, native or alien, must wash his clothes and bathe himself in water, and will be unclean until the evening, and [then] he will be clean; Leviticus 17:15). Representatives of all cultures try not to eat sick animals, or animals that have died due to disease.

Most predators have great potential for killing other animals. For example, the cheetah and other felines are capable of catching, killing, and eating prey that is larger than them. stalking and killing prey is a powerful driving force for many predators, and this can be observed in the example of a cat chasing a mouse chasing a cat or a hare. A 20-year study in New Zealand found that farm cats would travel three kilometers from their home to kill a rabbit.

Faking Death

One strong argument that predators are not looking for easy prey is the death faking that occurs among large quantity animals. If predators were looking for easy prey, then the prey's attempt to fall to the ground and play dead, rather than run and hide, seems suicidal. However, many animals that are attacked by a predator resort to this behavior, and it gives them a level of protection. Many insects, when trying to attack them, fall to the ground and freeze. And when the eastern snake Heterodon platyrhinos becomes frightened or injured, she rolls over on her back and feigns death. If you try to roll her over to her normal position, she rather comically rolls over onto her back. One gets the impression that in order to simulate death, she simply needs lie on the back.

There is another example of simulating death, which I remember from childhood, and which I studied later, when I became a physiologist. The tough shell of the North American box turtle Terrapene ornata provides her with protection from most predators. However, her behavior associated with the threat of a predator attack gives her additional protection for survival. In addition to the shell providing protection to the turtle, it retracts its head and paws inside its shell and remains motionless. She imitates death and it is impossible to get close to her. Soon the dog or any other predator loses interest in the turtle, which does not react to him in any way, and goes in search of more interesting prey.

Frightened by the approach of a predator, many animals try to hide in a safe shelter. This passive fear response is also common, but less well known than the classic fight-or-flight response. Hidden animals remain motionless and their metabolism slows, causing their breathing and heart rate to decrease. Unlike the sympathetically dominant fight-or-flight response, this passive response is parasympathetically dominant and reduces the prey's likelihood of being seen and killed by a predator. This reaction has been described for all major groups of vertebrates, including humans. From this we can only conclude that this deep physiological response has a high survival value.

There are differences in the way different animals respond to fear by hiding and freezing. Probably the most best example The "actor" imitating death is an American opossum, Didelphis virginiana. When he feigns death, his heartbeat slows by 98% and he is completely unresponsive to touch. You can even touch the mucous membrane of his eye, and it will not cause a blink reflex in him. Despite his dead appearance, he retains clarity of consciousness. When the predator retreats, its heartbeat gradually returns to normal. If the predator returns, its heart rate slows down again, even if the predator does not touch it. And this clearly proves the fact that the opossum is conscious and aware of what is happening around.

Figure 2.. Faking death by an American opossum. Photo by the author

The opossum's faking of death led to the creation of a popular expression in English. A person is said to be "playing possum" when he does not react to events around him. There is a similar expression with an even broader meaning that we often hear - “paralyzed with fear.” This is another manifestation of death simulation, giving high level protection from predators.

Scripture gives a great example of this reaction in a most unexpected source. Most people would agree that Roman soldiers were the best trained and most disciplined fighters of their time. However, having witnessed the bodily resurrection of Jesus Christ, even these experienced fighters were paralyzed with fear and imitated death: “When they were afraid of him, they trembled and became as if they were dead” (Matthew 28:4).

The instinct to “chase and kill”

Everyone knows that dogs like to chase everything - from rubber toys to neighbor's cats and cars. The same is true for most predators. They seem to enjoy chasing and killing. Let me give you a few examples to illustrate this important but not universally recognized aspect of predator behavior.

All herpetologists know that it is very difficult to get a predatory snake to eat prey that it has not killed. For example, a python will go without food for months before it agrees to accept an already dead victim. I had a boa constrictor for 23 years and often fed it fresh roadkill rabbits. However, in order to get him to eat dead prey, I had to heat the dead rabbit in the microwave and put it in the cage until it cooled down. Boas have labial heat sensors and prefer warm prey. This instinctive behavior helps many animals avoid eating dead prey, which could make them sick.

There are exceptions. Vultures are known for eating animals that have died due to natural causes, as well as animals killed on the road. Their stomach acid is extremely corrosive, allowing them to digest decaying carcasses contaminated with botulism and other bacteria that are fatal to other carrion-eating animals. Birds of prey, opossums and some other animals are known to be able to eat carrion without making them sick.

Mountain lions/cougars

While completing my doctoral dissertation on alligators at the Welder Wildlife Refuge in south Texas, I met a graduate student named Roy McBright. He was an expert at tracking cougars and mountain lions. Before entering university, he was a hunter, shooting harmful animals. He tracked and shot dangerous mountain lions that preyed on large livestock in the American Southwest and Mexico. He could determine which one attacked the victim by carefully examining the corpse of the killed animal. Each lion had personal preferences. Some of them preferred to eat first internal organs, such as the liver or heart. Others preferred muscle tissue. By following the lion's tracks, he could also determine what the lion was doing. For example, if a lion was simply moving from one place to another, he would walk through the lowlands and hide from prying eyes. If he was hungry and looking for prey, he moved from one high mountain area to another, scanning the surrounding area in search of food.

Rock McBright has conducted several studies that directly relate to the topic of this article.

Study No. 1 - Texas, USA

He was following the tracks of a large mountain lion in north Texas that was hungry and looking for food. McBright knew this because the lion came from one elevated place to another in search of prey. While hunting, a hungry predator noticed a deer whose antlers were tied to a fence. His tracks indicated that the lion approached the deer first from one side, then from the other, and then went to look for another victim. If he had been looking for easy prey, as is commonly believed among evolutionists, he would have killed and eaten the tied deer, but he did not. Details of this study and other observations of mountain lion behavior are detailed in McBride's master's thesis (1977).

Study #2 - Mexico

McBride collaborated with ranchers who protected herds from attacks by predatory mountain lions. In this area of Mexico, livestock is taken to market only once a year. Some calves were weaned from their mother too early and, being weak, did not keep up with the rest of the herd on the journey. They often fell behind and became easy prey for mountain lions. Lions always ignored young and weak calves and attacked and killed large healthy ones weighing about 300 kg. This once again demonstrates the fallacy of the evolutionary dogma that predators choose weak and sick animals as prey.

Study No. 3 - Florida, USA

Working with sheep farmers in Florida, McBride invented a special collar that sprays poison to kill mountain lions or other predators that attack lambs. The ranchers did not want to risk the strongest sheep, so they asked McBride to put similar collars on the weakest and smallest animals. In all cases without exception, lions did not attack such animals; they searched for and killed larger and healthier sheep. To deter predators, farmers allowed McBride to place collars on their largest and healthiest sheep. McBride continued his research in Texas and it yielded similar results. We were misled. Predators are not looking for easy prey, as evolutionists would have us believe. They prefer to experience the instinct of pursuit and killing, and seem to need it.

Of course, many other factors are involved in determining which animal a predator will choose as its prey. Small predators actually select small animals as prey. Other predators may rely on chance and hunt any animal that happens to be in the wrong place at the wrong time. However, the observations outlined above are still very important, and scientists need to better understand the details of what determines individual prey selection by different predators. And more research is needed in this important area.

Conclusion

Observations clearly indicate that predators do not choose weak, sick or young animals as prey, as evolutionists have long believed and taught. Many predators have the potential to kill multiple prey and can easily catch and kill a larger, healthy animal. It also seems that predators seek to experience the instinct of pursuit and killing, and actually ignore living animals that do not flee when approaching them. The faking of death by possums and other animals gives us clear evidence that something is missing in the modern worldview. The entire chain of relationships between the predator and its prey must be subjected to detailed study and re-evaluation. It seems that evolutionists are in error and one of the fundamental cornerstones of their theory is broken and will soon fall apart.

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Many representatives of the animal world of our planet are endowed with completely unusual methods of protection. This includes the expedient structure of the body, and defensive behavior, which ensures safety for a living being, and passive defensive reactions (such as the use of protective coloring and shape).

Sometimes nature clearly warns that you have encountered a dangerous creature, but sometimes even seemingly peaceful, inconspicuous creatures can cause a lot of trouble by unleashing their secret weapon, hidden for the time being.

The most in an interesting way The brachinus beetle, which lives in Africa and is also called the bombardier, uses self-defense.

This creature is capable of accurately dousing an enemy with a stream of burning liquid that has the temperature of boiling water and a composition corresponding to that used in binary chemical weapons.

Brachinus appears to be completely harmless. Nature has not endowed the bug with any marks indicating its extraordinary abilities and the fact that it releases the “explosive mixture” not just once, but in powerful rapid-fire volleys. Therefore, many insectivores, when meeting this creature, strive to immediately include it in their menu.

Only when already lying on the ground with bulging eyes and burnt oral mucosa does the predator realize that he was wrong and made a mistake in choosing the “dish”. In the future, the aggressor will prefer to take the tenth road around the literally explosive beetle. Brachinus also obtains food using an original method: it shoots drops of liquid from its abdomen, which, like artillery shells, knocks down flies.

Scientists call this insect a direct challenge to the theory of evolution. A real “chemical laboratory” operates in his body. An explosive mixture - hydroquinone (also known as a respiration substrate) and a 25% solution of hydrogen peroxide - is produced by a special pair of glands. Both substances enter the storage sac with a valve and an opening muscle.

The third additional gland produces a special respiratory enzyme-catalyst, hydroquinone oxidase, which is necessary for the components stored in the storage sac to enter into an oxidation reaction. The enzyme is contained in a so-called reactor chamber, lined with fabrics whose properties are very similar to asbestos.

At the moment when the situation requires decisive action from the insect, the contents of the storage bag are thrown into the chamber and... the instantly boiled substance, with a noise that resembles a shot from a scarecrow, flies out from the rear end of the insect’s abdomen and turns into a small cloud of acrid “smoke.”

Thus, when shooting back at a ground beetle, the brachinus fires 12-15 “chemical volleys” at slight intervals. And in the event of a collision with a more dangerous enemy, the beetle is capable of producing from 500 to 1000 emissions per second! Such “shelling” leaves serious burns on the attacker’s body.

By the way, scientists are convinced that such an original and effective apparatus of attack and defense did not “develop gradually” in the process of evolution (the first insects that decided to play with fire would have died before they had time to improve this weapon), but was part of the beetle’s body from the moment it appeared of this type. So, evolution has nothing to do with it, and there is Someone who provided a harmless and defenseless creature with a flamethrower? Perhaps, as always, we missed something in the structure of the universe.

The field jumping beetle also has the ability to actively protect its life. This insect, in a moment of danger, simply prefers to run away. At the same time, the baby not only flies quickly, but also runs well. For a predator, catching such a sprinter is not much pleasure. Moreover, it is actually almost impossible to achieve a positive hunting result in this case. But if you manage to catch a field horse, this will not bring joy either.

The beetle will begin to violently break out and bite frantically. The sickle-shaped powerful jaws of the insect can cause trouble even for humans, not to mention other representatives of the fauna! The bear behaves in a similar way in critical situations. But the earwig doesn’t try to escape. Instead, she assumes a menacing appearance and raises the ends of her impressive pincers above her head. By the way, they are so strong that they pierce human skin until it bleeds.

To intimidate predators and for hunting, many insects prefer to use poisons - secretions of special glands that can scare away, paralyze or kill the enemy. Wasps, bees, bumblebees and ants are familiar to everyone. These creatures received from nature as a gift special stings for injecting poison.

True, in the honey bee it is serrated and therefore gets stuck in the body of the attacker; the bee dies. So in this case we can talk not about individual, but about social protection, which develops a persistent reflex among those around them in relation to a whole species of insects. But a wasp can easily sting many times during its life. And to remind you that this is a poisonous creature, nature has endowed bees and wasps with a special warning color.

As for ants, representatives of some species of these insects not only pour formic acid on the enemy, but also add a mixture of two complex chemical compounds to the caustic “cocktail”.

They are specially synthesized in the insect’s body and have a pleasant lemon smell.

This mixture itself is poisonous, and it also promotes the penetration of formic acid through the outer integument of the animal. It is interesting that in the “chemical laboratory” of the little aggressor, not only “weapons” are created, but also many protective substances. Some of them can cope with the pathogens of cholera, tuberculosis and typhus!

The ant does not have to bite the enemy. Many strike the enemy at a considerable distance, spraying a poisonous mixture. For example, worker ants from the furmicin subfamily are able to “fire” at an aggressor located half a meter away from them! This distance is 500 times the length of the body of the warrior insect itself.

Leaf beetles also defend themselves with poison. They release a yellow-orange liquid through the joints of their body that has a pungent odor. A microscopic dose of this substance, entering the blood, kills a small animal. Larger enemies of the leaf beetle have greater health problems, so in the event of recovery, a persistent reflex to the “inedibility” of the beetle is developed.

Biologists had to observe how a toad or lizard, having accidentally grabbed this insect, tried to spit it out as quickly as possible, and then for a long time and carefully wiped their tongues and muzzles on various objects and plants.

Scolopendras are also seriously “armed”. Poisonous centipedes living in Africa, according to eyewitnesses, reach 47 centimeters in length. But we can only speak reliably about 5-30 cm specimens. Usually these creatures sit out in the ground or under a stone, waiting for prey - spiders, worms, cockroaches.

The centipede's venom also kills frogs and lizards that unwisely tried to snack on the centipede. But the mouse already has a chance to survive. After a scolopendra bite, a person feels general malaise, pain and fever. Only giant specimens that dig into the neck with poisonous jaws pose a serious threat to children.

Blister bugs, despite their small size, are very dangerous. Their poison is so strong that even large domestic animals often die after eating this crumb along with the grass.

In the old days, pharmacists used dried blisters to make blister plaster.

Some wingless grasshoppers use poisonous foam to protect themselves. In case of danger, foam begins to emerge from their mouth and chest with a hissing hiss - a mixture of quinine, air bubbles and phenol. Cicada larvae do the same thing. But sawfly larvae have an even more original “weapon” against aggressors.

Feeding on pine needles, they collect tree resin in special sacs connected to the intestines. In a moment of danger, the caterpillar releases a piece of “strategic reserve”, inflates it and shoots it at the enemy. The sticky substance glues the ants' legs together and makes the birds lose interest in such "nervous" prey.

In addition to poison, the smell can also scare away predators. And not just any one, but a particularly unpleasant one. In the “arsenal” of many insects there are special glands responsible for the formation of a secretion that emits a rare stench and leaves the enemy with long memories of the meeting.

To scare away enemies, insects often use some behavioral techniques. For example, the Apollo butterfly, in case of extreme danger, falls to the ground, begins to cross its legs and hiss threateningly. At the same time, it vigorously spreads its wings, on which there is a sign notifying the attacker that the insect is poisonous - bright red spots.

But the praying mantis, if necessary, rises, takes a threatening pose, spreads its hind wings, begins to creak its abdomen and click its grasping legs. After this, there are few people who want to get acquainted with the main “argument” of the praying mantis - its jaws. Defensive postures (often combined with a repellent odor or poison) are also widely used by various caterpillars.

Sea creatures also know how to defend themselves from attack. Many of them are extremely poisonous. Needles, skin, mucus, special stinging threads, unexpectedly sharp “scalpels” filled with poisons, before which the capabilities of even the famous curare pale - all this “arsenal” of a number of representatives of the sea people is dangerous not only for animals, but also for humans. And the electric stingray is quite capable, if not of killing, then of stunning its victim. As for electric eel, then it’s better not to meet such a “living power plant”!

Unlike other “armed” inhabitants of the sea, the octopus is a completely intelligent creature. He does not try to stun the enemy with an electric shock or treat him with a horse dose of poison. If a cephalopod encounters danger, it prefers... to evaporate, releasing a dark cloud. The ink-like liquid that the octopus “shoots from a special bag quickly spreads into a dirty mist, hiding the path sea creature to retreat.

True, there is no rule without exceptions. An extremely cute, but malicious, tiny ringed octopus, a resident of the Indian Ocean, can cause the death of a person. Its poison, injected using a sharp “beak,” causes paralysis of the heart muscle in a matter of seconds.

Snakes are a separate article. Many of the reptiles are dangerous because of their poison. At the same time, there are individuals that can cause major trouble or even kill, both with a bite and... spitting! But among the poisonous creatures, the famous black mamba stands out especially, “from the bite of which a person dies five minutes before the bite.”

Believe me, this is exactly the case when the joke is only part of the joke... And non-venomous individuals - by the way, the vast majority of them - use serious muscle force to attack, which allows the snake to strangle its prey. " Secret weapon“Some lizards and representatives of the spider family are also endowed, such as the notorious “black widow”, crosses, tarantulas and scorpions.

Can also be found in mammals unusual ways self-defense.

The mammals of the skunk family are perhaps most famous for their method of defense against predators. Skunks usually do not try to hide from their enemies. Instead, the animal first raises its fluffy tail and sometimes stomps its paws on the ground.

If the warning does not help, the skunk turns its back on the enemy and “shoots” an oily yellowish liquid at him, usually aiming at his eyes. Some skunks (Mephitis mephitis) are able to hit an enemy from a distance of more than 6 m.

This liquid is the secretion of two glands located to the right and left of the skunk's anus, and is a mixture of sulfur-containing organic matter(methane- and butanethiols (mercaptans)), which have exceptionally strong, persistent and unpleasant smell. The muscles surrounding the mouths of the glands make it possible to accurately shoot the secretion at a distance of 2-3 m. The main component of the skunk “jet” - butyl selenomercaptan (C4H9SeH) - can be determined even in the amount of 0.000000000002 g.

If it gets into the eyes, this liquid causes a burning sensation and even temporary blindness. However, the skunk’s glands contain fluid for only 5-6 “charges”, and it takes about 10 days to restore them, so the skunk spends “charges” reluctantly, preferring to scare off potential predators with its contrasting coloring and threatening poses. As a rule, skunks are attacked by young predators unfamiliar with their method of defense. The exception is the Great Eagle Owl, which hunts skunks systematically.

The smell of skunk is so persistent that spoiled clothing usually has to be burned. Folk remedies like tomato juice, vinegar or gasoline do not destroy the smell, but only mask it. Dry cleaners use hydrogen peroxide (H2O2) to combat it.

The platypus is one of the few poisonous mammals (along with some shrews and sawtooths, which have toxic saliva, as well as slow lorises - unique gender known venomous primates).

Young platypuses of both sexes have the rudiments of horny spurs on their hind legs. In females they disappear by the age of one year, but in males they continue to grow, reaching 1.2-1.5 cm in length by the time of puberty. Each spur is connected by a duct to the femoral gland, which produces a complex “cocktail” of poisons during the mating season.

Males use spurs during mating fights. Platypus venom can kill dingoes or other small animals. For humans, it is generally not fatal, but it causes very severe pain, and swelling develops at the injection site, which gradually spreads to the entire limb. Painful sensations (hyperalgesia) can last for many days or even months.

Other oviparous animals, echidnas, also have rudimentary spurs on their hind legs, but they are not developed and are not poisonous.

Slow loris - the only one famous family venomous primates and one of only seven known venomous mammals. The poison is secreted by glands on the forelimbs.

Mixed with saliva, the poison is either smeared on the head to repel predators, or is kept in the mouth, allowing the loris to bite especially painfully. The poison of slow lorises can cause suffocation and death not only in small animals, but even in humans.

So, many of our “smaller brothers” own an entire arsenal, sometimes quite unexpected means defense and attack. Thus, nature made their life easier and forced larger predators to respect the little “warriors.”