Environment hare in the forest
Fact fitness of organisms to the conditions of their dwelling, the church for a very long time used as the supposedly “scientific” proof of the existence of divine power. Only Darwin's theory finally refuted the myth of the “original, god-given” fitness. In the light of Darwin's theory, adaptability turned out to be necessary and a natural consequence of natural selection.
As an example of making fitness through the development of a protective coloration in so many animals. About 100 years ago in England, the light gray moth birch moth was very widespread. During the day, she sits on birch trunks — and the bright coloring of her folded wings masks the insect well. But in connection with the development of the industry, the soot of numerous factory pipes gradually began to precipitate on the white-trunked birches growing in industrial areas. The bark has acquired a darker color. Under these conditions, the once masking coloring of the moths ceased to be useful. Due to changing conditions, the direction of selection has changed. If earlier (on white trunks) birds ate primarily darker butterflies, but lighter survived, now (on dark trunks), on the contrary, the darkest butterflies survived, and the lightest victims of birds this process continued from generation to generation for last 100 years. And now, British zoologists have relied on two different peppered races: in rural areas, the old bright one still lives, and in industrial areas a new very dark race. So, for a relatively sober period of natural selection, one of the devices was developed - the patronizing coloring of these butterflies.
Very interesting how examples of facial expressions and masking. When mimicry individuals of some defenseless species with their shape, color, behavior resemble the other, with its active means of protection. An example would be defenseless flies, “imitating” such armed insects as bumblebees or wasps. Masking is achieved by the similarity of animals with the bodies of inanimate nature. For example, the caterpillars of some insects in a stationary state are very similar to a tree knot; The Kallima butterfly with folded wings is remarkably similar to a dry leaf of a tree.
A wide variety of adaptations to cross-pollination, to the distribution of fruits and seeds are widespread among plants. In animals, various kinds of instincts play an important role as adaptations (caring for offspring, instincts associated with the extraction of food, complex instincts of such social insects as bees, ants, etc.). There are many similar examples in zoology and botany.
One of the main evidence of natural origin of fixtures - their relative nature. Any adaptation is useful only in relation to the conditions in which it historically arose. Let's take the example analyzed above: the bright color of the moth is useful in rural areas, dark - in industrial areas. But also for the given conditions in which this or that device was developed, its usefulness is also relative. First, the organisms protected by these or those adaptations fall victim to their enemies, although in a smaller number than their worse protected counterparts. Secondly, constantly fluctuating environmental conditions often create situations in which the device ceases to “work”. So, for example, a device in the form of a change in the color of hair is very useful for the white hare: in the summer this hare is dark and in the winter - white. But in some year the snow cover went to bed very late, and the hare turned white long ago; under these conditions, his white coloring instead of patronizing will be unmasking. And in such time many hares die. A very important evidence of the relative nature of fitness is rudiments, that is, organs that have lost their usefulness in new conditions, but which have not yet completely disappeared.
White hare: nutrition, reproduction, adaptation to life
White hare inhabits various biotopes - from the arctic tundra and northern coniferous forests (taiga) to the mountains, where it settles above the forest border. In many places, the white hare can hide only in a few shelters, so the whole year it has to endure icy wind and rain. The white hare is perfectly adapted to life in cold regions lying in the north or high in the mountains. It can even transfer a temperature of -40 C. White hare feeds mainly on grass, low shrubs and various perennial herbs. In his shelter, he remains until dusk and only then goes in search of food.
With the advent of winter, animals living in the southern regions of the tundra move to the edge of the taiga, to unlimited coniferous forests. Here they find better protection from cold and wind. White hares, who spend the winter in the open tundra, can find shelter only behind the rocks and under low bushes. In Scandinavia, the white hare is kept all year round in food-rich taiga areas.
Breeding hare
During the mating season, males become very aggressive towards each other. Almost the entire period of attacking each other and fighting for females. Mating occurs in March, but in the tundra it is postponed to a later date and occurs in late May. Hares are born 50 days after mating. The female feeds the hare with milk once a day. All brood keeps near to mother, not running up. Sometimes the hare tries to take the enemy away from the kids, pretending to be wounded.
The adaptation of the hare to life
The white hare, like many other herbivorous animals, becomes prey of predatory animals. In winter, when everything is covered with white snow, the hair of the white hare becomes completely white, therefore the animal is almost invisible on snow and ice. In spring, the color of the hare's hair changes again (depending on the temperature) to dark, blackish-brown or brown-red. These changes are governed by the temperature and duration of daylight. These animals simply need to adapt and blend in with their surroundings.
In places where there is no snow, the white hare does not change the dark color to white. For example, white hares, who live in northern England, have variegated wool in winter. In some subspecies of the white hare that live in the Arctic, wool remains white in the summer. For a hare, good vision, smell and speed are also important. The eyes of the hare are located quite high on the sides of the head, which gives it a very wide field of view. The hare simultaneously inspects a large area of space. Having noticed the enemy, he first freezes in place in the hope that he will not notice him. Seeing that he was found, he flees. In the snow, the hare digs tunnels, hiding from predators and frost.
Winter coat: very thick, especially on the auricles. White paint provides masking on the snow-covered expanses. Summer wool: in summer the coat is not so thick and is colored brown-gray or reddish-brown. Ears: the white hare has short ears, which prevents excessive heat loss. The black-tailed hare, which lives in the desert regions of California, has very long ears, which ensure good cooling of the body. Paws: foot covered with thick hair. Wool protects the hare from the cold and helps it to confidently hold on to the snow and ice.
Nowadays, the disappearance of a hare is not threatened. However, its habitat in cold climates has specific features, so the intensive use of the Arctic and the pollution of these regions gives grounds for concern.
White hare: nutrition, reproduction, adaptation to life
White hare inhabits various biotopes - from the arctic tundra and northern coniferous forests (taiga) to the mountains, where it settles above the forest border. In many places, the white hare can hide only in a few shelters, so the whole year it has to endure icy wind and rain. The white hare is perfectly adapted to life in cold regions lying in the north or high in the mountains. It can even transfer a temperature of -40 C. White hare feeds mainly on grass, low shrubs and various perennial herbs. In his shelter, he remains until dusk and only then goes in search of food.
With the advent of winter, animals living in the southern regions of the tundra move to the edge of the taiga, to unlimited coniferous forests. Here they find better protection from cold and wind. White hares, who spend the winter in the open tundra, can find shelter only behind the rocks and under low bushes. In Scandinavia, the white hare is kept all year round in food-rich taiga areas.
Breeding hare
During the mating season, males become very aggressive towards each other. Almost the entire period of attacking each other and fighting for females. Mating occurs in March, but in the tundra it is postponed to a later date and occurs in late May. Hares are born 50 days after mating. The female feeds the hare with milk once a day. All brood keeps near to mother, not running up. Sometimes the hare tries to take the enemy away from the kids, pretending to be wounded.
The adaptation of the hare to life
The white hare, like many other herbivorous animals, becomes prey of predatory animals. In winter, when everything is covered with white snow, the hair of the white hare becomes completely white, therefore the animal is almost invisible on snow and ice. In spring, the color of the hare's hair changes again (depending on the temperature) to dark, blackish-brown or brown-red. These changes are governed by the temperature and duration of daylight. These animals simply need to adapt and blend in with their surroundings.
In places where there is no snow, the white hare does not change the dark color to white. For example, white hares, who live in northern England, have variegated wool in winter. In some subspecies of the white hare that live in the Arctic, wool remains white in the summer. For a hare, good vision, smell and speed are also important. The eyes of the hare are located quite high on the sides of the head, which gives it a very wide field of view. The hare simultaneously inspects a large area of space. Having noticed the enemy, he first freezes in place in the hope that he will not notice him. Seeing that he was found, he flees. In the snow, the hare digs tunnels, hiding from predators and frost.
Winter coat: very thick, especially on the auricles. White paint provides masking on the snow-covered expanses. Summer wool: in summer the coat is not so thick and is colored brown-gray or reddish-brown. Ears: the white hare has short ears, which prevents excessive heat loss. The black-tailed hare, which lives in the desert regions of California, has very long ears, which ensure good cooling of the body. Paws: foot covered with thick hair. Wool protects the hare from the cold and helps it to confidently hold on to the snow and ice.
Nowadays, the disappearance of a hare is not threatened. However, its habitat in cold climates has specific features, so the intensive use of the Arctic and the pollution of these regions gives grounds for concern.
