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THE MENAGERIE AT THE PORCH
FROGS

PRINCESS SCIENTIFIC EXPERIMENTS

...Frogs only education is not enough, and they are all capable of.
Mark TWAIN

"The famous jumping frog of Skelita" - the heroine of the story M. TWAIN - jumped on his bug-eyed rivals and brought the owner a fair price. Alas, frog achievements in that time, obviously, were not recorded, at least in TWAIN on this account there are no numbers. But sorry. They could be compared with values known to science.

Frogs of Central Russia are jumping on the 30 - 40 cm. Much further jumping frog-bull living in America, and "frog-Warbler"living in Western Europe, jumps for three meters. Absolute world record - 409 centimeters.

The legs of the frogs anywhere. One day they brought her in experimental science, and helped to become famous Luigi Galvani. However, "animal electricity" was discovered when Galvani still and there was no light, but the discovery went unnoticed. Spectacular as the experiments of the Italian then shook the scientific world: just think, cut frog legs came to life, shuddered at the iron bars of the balcony - their nerves were still stored electric charge. Since then, the frog became the Princess of the experiment.

When in 1866 against the I. M. Sechenov as the author of "Reflexes of the brain" was filed, the great physiologist said: "Why do I need a lawyer? I will take to the court a frog would do before judges all my experiences: let then the Prosecutor denies me."

Now experiments with frogs prosecutors are not interested in. Now with the opening of the little creature decided to start everyday practical training in physiology. And then the students are already becoming eminent researchers often do not part with their cute heart Skamania is a convenient laboratory animals. Only at the Leningrad University about 15,000 frogs annually "put their bellies on the altar of science. And how many in the world of universities and research centers, where in the name of knowledge stop beating heart of amphibians!

On Earth is home to over 200 species of true frogs, the rest are not real. All, so to speak, true frogs horizontal pupil and a forked end language. We were familiar with only a few species: two large green frog (lake and pond), which can't be solved far away from the water, and two of them are brownish girlfriend smaller grass and moor), bravely leading terrestrial way of life.

Not experienced in systematics people take for frogs their relatives - jermanok, chesnochnitsu, tree frogs. To understand who you are dealing with, it is necessary - as a doctor at the reception to ask: "Hey, show us your tongue..."

Frog forked tongue that in mind. And her mind busy is not a global problem, and the insects and bugs. Supported not only is it gentle gnats, but, like a lizard, which was just discussed, bitter God cows and smelly wood bugs. If the frog would distinguish between food taste, her tongue was instantly jerk away from unbearable bitter picric acid. Her to feel that stuff, shoving a laboratory, it is necessary three seconds.

And still the frog language is not simple. It is not unusual only because, being folded in half, suddenly instantly POPs up and catches a bug flying by, but also that responds to the seasons. The reaction of this can be seen under the microscope - in the language appear and disappear so-called dumbbell cells, similar to paralytica dandelion.

At the Institute of normal physiology of the Academy of medical Sciences of the USSR learned that these dandelions in frog language bloom in winter, and by March shrinking. In June, the language of common frogs completely naked - no flowerbeds under the microscope is not visible. In August dandelions appear again to blossom for winter in all its glory. What is the reason? Perhaps that paralytica seems to have the same taste cells that frogs could not be found. But then there is a new puzzle - winter frog sleeps, why should she at this time the taste?

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The menagerie at the porch

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