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THE MENAGERIE AT THE PORCH
CROWS

CROW EGGS

Jonathan swift has rows that have some relation to the stealthy representative of our fauna. The writer tells how one morning the chief Secretary for secret Affairs of a great Empire of lilliput told Gulliver about the terrible disaster caused fierce decree of the Emperor. The decree obliged to break up chicken eggs with the pointed end.

"This decree to the extent angered the population that... was the cause of six uprisings, during which one Emperor lost his life, and another crown... Count to eleven thousand fanatics who went on the death penalty for refusing to break the eggs with the pointed end. Were printed hundreds of great works on this issue. However, the book of topochemical have been banned long ago, and the party itself deprived of the right to hold public office".

As in lilliput lived ravens, swift silent. Meanwhile, according to the Imperial decree, they should be executed: the ravens clearly gravitated to the disgraced party topochemical. For eggs, stolen in the chicken coop, the birds fanatics have preferred to break with the blunt end. Gulls and other robbers, salassi in someone else's nest, immediately split eggs, and a crow, perhaps ashamed of the contents of the egg it absorbs far from the place of theft: the crow first transporting stolen goods. Pockets have cheats no, bags and briefcases she's also not in favor. And bulky egg and look slipped out of the beak. Not to clanger, Raven punches a hole in the blunt end (it is easier to make), inserts into the hole of the upper half of the beak and holding the bottom of the lower half of the beak fragile food, escaping from the chicken coop.

In the Perm pedagogical Institute decided to find out why the chicken, crow, and other eggs do not roll in the nests of hit or miss, and stacked sharp ends inside. Outward or upward looking only blunt ends.

What would it be? And here is why. When the bird clinging to the shell, incubates, the air in the lower part of the nest stagnates and the carbon dioxide content increases five to nine times. Carbon dioxide, as is well known, not so fresh: the germ needs oxygen. It is here where the dog is buried inside the eggs oxygen gets easier with the blunt end: there are more microscopic pores and under the shell usually has an air bag. That is why in the Cup-shaped nest eggs and look blunt end of the output: it is easier to breathe in oxygen.

That the eggs do not inadvertently turned over their center of gravity is shifted to the sharp end. Due to this, the birds can pull the eggs from side to side. Yes and the whole process of incubation is some fixed word is actually full of movement. Here is a description of a naturalist: "In binoculars it is clear that in the nest there is a noticeable movement. The bird is a little lifted and a few moments as if prostoit, quickly going over your feet, why startled wings and body. These strange, at first glance, the birds contribute to the ventilation of the nesting tray. It lasts from a few seconds to half a minute and is repeated so often, that the bird, in fact, never sits still on eggs".

The grey crow airing takes seventeen days until Wiklund Chicks. (They have a month to spend in the nest, and then razevaya bill). In order not to lose shape, the female "ventilated" and truly. Leaving the nest in the care of his father's, will listen, will shape the feathers and do the exercise - take over the neighboring trees or roofs. Anyway, crow's nest remains neglected. No wonder people say stupid that bird, whose nest is not cute. And the crow is a really bird's genius. But more about that a little later.

In the Arkhangelsk region in the nests of grey crow "open their mouths" on average three fledglings in the suburbs of 4.8, and in the grace of Krasnodar Krai - five juveniles require food.

C. A. Bakhmutov watching crow nests in the lower reaches of the Ob river, noticed that the eggs, laid the first shell is olive green with clear spots. Then paint weaken, and the last egg color varies from pale green with a barely noticeable spots to clear blue. Such differences can probably be explained by the fact that in the body of the female by the end of the clutch decreases the secretion of pigment. Hence, the ravens played out. A curious detail: the first light usually appears crow, male. Is there some connection between time diocletiani, sex chick and color of the shell?

Generally with crow dye-house ought to understand, and not just with a phrase like, "describe the form is interesting because the plumage falls into two groups - grey and black". Black Raven, as the name implies, being all black, so that the gloss metallic luster. But many grey dark: head, throat, wings, tail, beak and feet. Black chose the Eastern parts of the country, gray - West. In the steppes of Kazakhstan and the Yenisei meet their hybrids. However, the black crows live in Central Europe.

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The menagerie at the porch

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