Why do bats hang upside down? How to understand a parrot: bird gestures What do swifts eat

The age old question about bats that like to hang upside down. Yes, it's really strange why an animal, a mammal, prefers to be in this position. Of course, some types of monkeys like to behave in this way, but only when they have nothing to do with themselves. But the bats- the only living creatures that really spend most of their lives hanging upside down: they feed, care for offspring, nest and sleep.

There are very good reason why they do it: to take off, they need to hang upside down.

To begin with, we must recognize that bats are not birds or insects that use standard flight techniques (as opposed to gliding flight). The difference between the flight of a bat and that of a bird or insect lies in weight—for example, in the ratio of weight to the lift of the wings. If you approach a bird or insect, most species will be able to quickly take off from a stationary state.

And bats can't do that. They have serious difficulties when taking off from the ground (not to say that it is impossible, they can do it ... it's just very difficult). Insects and birds often jump into the air as they take off to find the right direction in flight, then their strong wings lift them up and up rapidly. Birds have hollow bones, and bats No. Insects are composed of light chitin or soft tissue; bats are not. And mice don't have what we call "powerful" wings. These beautiful creatures are primarily mammals. The only mammal that can fly. Nature acted outside the box and endowed them with wings, so they had to compromise. Bats are great in the air, and in some ways will give odds to birds. The only problem is takeoff.

To compensate for the presence excess weight mammal and difficulty in taking off, evolution has found another way to transition from stationary to flight in bats. Evolution decided it was best to hang them upside down to make it easier to swing.

It was a great idea, as it turned out. Except that a bat cannot land on a branch. They are mammals, not birds, and their musculature, bones, and tendons are built differently. When a bird sits on a branch, the paws firmly grasp the branch due to the peculiarity of the tendons. This happens automatically. This common feature for all kinds of birds. And the answer to the question why they do not fall in a dream.

In mammals, everything is arranged differently. Therefore, in order to compensate this fact, nature decided to endow them with the ability to hang upside down. Thus, their tendons are arranged in such a way that they close the paws from the back, not like in birds. Here is the result of evolution. When a bat hangs and suddenly needs to fly away, it simply opens its paws and takes off in the process of falling. In fact, using this gravitational method, they achieve instantaneous flight faster than birds, which have to cope with the force of gravity.

Note: If you're wondering how bats defecate in this position... that's not a problem. The feces are like grains of rice, they just fall down to the ground when the mice are in a hanging position. They only urinate during the flight.

So now everything is clear. Bats hang upside down, since they are mammals and cannot fly into the air like birds (at least without problems). But if they need to take off, they just let go of what they're holding on to. Makes sense, right?

Evolution: the more you learn, the more interesting you learn

In general, here, in the Astrakhan hunting grounds, there are a lot of raccoons (raccoon dogs). I remember an incident when we camped on the banks of one of the tributaries of the Volga. Every evening a couple of raccoons came to us in the light and thoroughly cleaned the place where we put the rest of the food from our table. At the same time, they squabbled loudly, without sharing any fish head or bird bone.

And one day, when we were sitting at the table by candlelight late at night, I found a raccoon sitting at my leg in the manner of a dog. Our dogs were spinning somewhere to the side; finding an uninvited guest, they immediately drove him away, but I think not far ...

Today we are going by car to the far end of the island - the so-called Cape Cormorants. According to our host, this is the most pheasant place. We get out of the car and decide to explore the area surrounding the lake. Here are dry eriki, big trees and bushes. Kat, let out of the car, instantly begins to rush along someone's crowds, and pheasants take off one after another.

Apparently, a whole flock fed here, but these are only chickens, and we lower our guns with regret. We part slightly, and Kat with a rack works out a brood of partridges, one of which I took. Go ahead. A hare jumps out of dry reeds, but it makes no sense to shoot far. Turning around, he walks back into the reeds, followed by Kate. We pass a hundred meters, and again a hare jumps out of these reeds, apparently the same one, and right at us. Serezha shoots, we are again with meat.

An unexpected surprise awaits us at the edge of the lake. Almost from a clean place rises none other than a woodcock. We stop and think for a long time about where he could come from in November. After all, the path of the autumn passage of the woodcock in our area goes towards the Black Sea, and here only the Caspian is ahead.
We moved on. Dogs literally dive into the reeds that grow along the shores of the lake; one by one the pheasants rise up, and all the roosters.

The guys run as fast as they can, trying to keep up with the dogs, so as not to miss the opportunity of true shooting, which turns almost into a cannonade. Kat is ahead of this whole human and canine team, and with her hunting passion, she is not up to the owner now. My age no longer allows me to run and shoot at such speeds, so I walk closer to the coastal bush in the hope that I will get something from this hunting feast.

And for sure: in front, parallel to my course, a pheasant runs, about twenty meters away from me. He apparently does not want to climb onto the wing, but quickly runs with long strides - you can’t even think that a bird is capable of such a thing. I wish this nimble runner a happy journey, especially since she is a chicken.

In general, a running pheasant is a difficult bird for a pointing dog. Having sensed him close, the cop makes a stance, and if he does not hide, he runs with all his might, significantly breaking away from her. For such a pheasant, a spaniel is more suitable, which chases a bird without stopping, and overcomes reed and other supports more easily than a setter. But when hunting with a spaniel, you usually have to get a good run.

I walk sideways along the lake, and now my hopes were justified. A pheasant raised by dogs in the reeds flies straight at me. I hit, and he, heavily flapping his wings, sits on a tree about forty meters from me. The bird sits openly sideways to me. Without thinking, I shoot at her from the second barrel and see that I hit. But, swaying, shaking himself, the pheasant continues to sit. I reload and hit again over and over again - it sits. Another doublet and the bird finally falls. Apparently, the fractions of the seven and cylinder barrels are not enough for such a distance.

Picking up a beaten rooster, I remember an old incident. One spring, my friend and I, while in the Arkhangelsk region, went to the capercaillie current. A friend, as the owner of the current, went first, and soon I heard a single shot. After that it was my turn. The capercaillie song was not long in coming, and I successfully jumped up to the singing rooster, still in the dark. He shot a unit of meters from twenty. After the shot, the bird did not fall, but turned head down, hung on a branch, holding on to it with one foot. I walk up to the tree. The bird hangs, showing no signs of life, its wings are spread, its head dangles.

The thought arises that the death cramp has reduced the capercaillie's leg and he hangs on it, being already dead. I decide to kill with a shot the bough on which the bird hangs. He shot half the cartridge belt, but at least that bitch. I stand under a tree with a broken gun and think about what to do next. And suddenly my capercaillie started up, pulled himself up on one leg and sat down on a bough; after sitting for two seconds, he took off noisily and disappeared into the tops of neighboring fir trees. I, as I was with an open mouth and a broken gun, remained standing still. A friend who came up, heard my shooting, thought that at least a bear attacked me, and hurried to help.

But enough of the memories, it's time to get back to reality. I come closer to the shore of the lake and see how Kat puts another pheasant right on Seryozha. The hunter beats, and the bird falls dead into the liquid mud almost to the very middle of the lake. Remembering my yesterday's torment almost in a similar swamp, I sympathize very much with Serezha, but it wasn't there. Kat rushes into the liquid mess and pulls the bird to a dry place.

Actually, I never taught my pointers to serve dead game from the ground (this is not a royal business!), But from the water - always, but for this it took some effort.

We go along the lake further and go to the opposite shore. Here the water comes to the very edge of the earth, there are no reeds, which means that the pheasants have nothing to do here. We delve into the forest, consisting of shrubs and tall trees surrounding dry erik. Kat starts rummaging through the trees, and here it is: about five birds rise from the bushes, all roosters, and fly right at us.

We unload the barrels in full, but in vain: the pheasants both flew and continue to fly. Of course - all muffs. We pass further than about five hundred meters and see Paula, standing with her head down, waving a rod. We come closer. What is a parable? A dog stands over a deadly beaten pheasant - a nurse, and nothing more! Apparently, during our erratic shooting, they still got one bird. We head through the reeds closer to the car.

We've been here before, and there shouldn't be pheasants, but Kat is getting there anyway. Who would it be? Forward! And again, from an almost completely clean place, a woodcock rises - apparently, the same one that was picked up when approaching the lake. I shoot - and the bird is in my hands.

The woodcock is large, heavy, swollen with fat. This is not a spring flyer for you, consisting mainly of a sublimate of feathers, bones and dry muscles. Of course, against the background of golden pheasant roosters, the woodcock looks like a small gray bird, but if you look closely ... Here and at this time it is a very rare trophy and, accordingly, an enviable one. And the dog - oh yes Kat!

But back to the Astrakhan reeds. We returned home with rich booty and impressions, had a hearty dinner, drank the traditional “blood cup”, heated the stove and went to bed, fortunately, our four-legged friends were already snoring peacefully. What else does a hunter need? Here it is - our joy!

During the rather frequent hunting trips, sometimes for almost a whole month, my comrades and I had to eat exclusively game, and sometimes fish cooked without any culinary tricks, most often right on the fire. And believe me, this food, usually consumed for breakfast, lunch and dinner, has become boring to hell.

So now, when I get to a feast where hospitable hosts offer a whole woodcock wrapped in bacon and taken out of the oven in front of your eyes, or a pheasant stuffed with prunes and nuts, baked in Antonov apples, I always answer the same way: “Can I take my share of sausage?” However, there are exceptions to this rule - fried quail.

The swift bird is perhaps known to everyone. It can be seen both in the city and beyond. And this is not surprising, because swifts are one of the most common representatives of birds on the planet. They live on all continents, with the exception of Antarctica and a few islands.

In summer, these birds rush through the air with loud, screech-like cries. People are used to them and no longer pay attention to them, but they do not know that they are seeing truly unusual birds.

Swift bird: description

Here are the main characteristics of the appearance. The body of swifts in length reaches 10-24 centimeters, weight ranges from 50 to 140 grams. The head is large, the eyes are dark, the beak is short and sharp. The wings are curved and long, the tail is forked or straight. The legs are small and weak. The fingers point forward, the claws are sharp.

Mostly birds have a dark color, black and gray colors, however, there are also white-belted swifts. White color is present, as a rule, on the undertail, throat, belly and forehead. Females and males in appearance have no difference.

In summer, everywhere, even in big cities, you can watch flocks of dark birds screeching in the sky. These are black swifts, which are most common in cities. At the same time, in the eastern regions of our country and in some other states, the bulk of the "urban" are white-belted swifts. In general, white and black birds are similar both in appearance and behavior.

Lifestyle

The swift bird belongs to the order of swift-like birds. In general, in nature there are about eighty species of representatives of this order. There are both migratory species and sedentary individuals. Swifts, as a rule, live in flocks, and prefer to nest in colonies, which in individual cases reach several thousand pairs. These birds are active from early morning and until the evening.

What do swifts eat

The birds in question are highly dependent on temperature. environment and weather conditions, which is their main hallmark. If a swift bird is starving, its body temperature can drop to twenty degrees. That is why these birds have the ability to fall into a kind of torpor.

Swifts eat insects, which they catch in the air with their beak, like a net. If food cannot be obtained, the birds plunge into a kind of hibernation and can spend several days in this state, until weather won't improve. Not only adults, but also chicks of this species have this ability. In "hibernation" they can last for about nine days, while the parents fly several kilometers away in search of food.

Long-distance flights to get food are called weather migration. Wintering bird swift flies away, as a rule, in August. However, again, in this case it all depends on the weather.

reproduction

These birds nest in trees, hollows, rock crevices, burrows and caves. It all depends on the habitat. Birds live in forests, cities, mountains and deserts. Pairs create for life.

The swift's nest is built from vegetable fibers, twigs and feathers that birds pick up on the fly. Every year the birds return to their former nests. Construction of the dwelling lasts about a week.

Eggs are incubated by females for 16-22 days, at which time the male flies away in search of food. The clutch usually contains eggs. white color, there may be four or only one.

The chicks do not leave the swift's nest for 33-39 days, depending on weather conditions. Parents feed them several times a day with compressed lumps of saliva and insects. Then the chicks fly away, because they are already fully prepared to live an independent life.

• Swifts cannot swim and walk, but can only sit on tree branches and fly. Therefore, birds drink, eat and even bathe on the fly.
• When bad weather conditions are observed, and the swifts realize that they will not be able to feed the chicks, they throw the eggs out of the nest.
• This is the most fast birds, whose flight speed can reach 170 kilometers per hour.
• Some species are able to sleep on the fly, while the time of such rest can reach several hours.
• IN wild nature these birds live ten to twenty years.

Difference from swallows

Swifts and swallows are very similar in color and size, so they are often confused. However, upon closer examination, it becomes clear that these are completely different birds. They even belong to different units.

Swifts and swallows are quite comparable in size: the same wingspan, the same body length, but the weight of a young swift is twice more weight swallows. They also differ in color. Despite the fact that the plumage of both of them is dark, in swifts it has a greenish tint, there is a slight White spot on the chin and throat. Distinctive feature the swift also has a sharp beak, with which it seems to cut the sky (hence the name).

Swallows have normal bird feet with three fingers pointing forward and one pointing back. Thanks to this structure of the paws, the birds are easily kept on the perch and move along the ground.

Swifts have unique paws. All four fingers point forward, making it very difficult for the birds to keep their balance. This feature determined the manner of sleeping swifts: they hang upside down on a bitch, because they cannot stand. In addition, forward fingers make it difficult to take off from a support, but once the birds take to the sky, it is already forgotten how stupid they look on the ground. In flight, swifts reach speeds of up to 170 km / h, while swallows - only up to 60 km / h.

Another difference is that after wintering, swifts arrive last, while swallows are the harbingers of spring.