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Video: Amazing Frogs
If the animals were awarded prizes, frogs could well qualify for the first prize for strangeness
Moreover, a worthy candidate could be not only a tiny Cuban frog the size of a fingernail, and not a Cameroon goliath frog weighing a good six kilos, whose hips are a gourmet's dream, and not an African tree frog that can jump five meters, and a non-flying frog from Borneo, between the legs of which sensitive membranes are stretched, and not a "Catholic" frog with a black cross on its back, and not a hairy Brazilian tree frog, which, having fallen from a height of forty meters, does not even fill itself with a bump, and not a "paradoxical" frog, whose tadpole is four times the size of an adult - no, a simple frog would adequately represent its genus in this competition.
Bull frog (Lithobates catesbeianus)
Whichever side you take, you immediately come across a strangeness - from our, human point of view.
One fine day in 1785, the famous Italian biologist Spallanzani took out a pair of lungs from a frog to see what happened. But nothing happened. The frog, devoid of lungs, continued to gallop and catch flies as if nothing had happened.
Intrigued, Spallanzani repeated the experiment with other frogs - the same effect. And the wise experimenter made a sensational conclusion: "In frogs, oxygen absorption occurs through the skin!"
However, frog skin has not yet revealed all of its secrets. British naturalist Edwards placed the frog at the bottom of the duct in a special netting to prevent it from rising to the surface. But the tailless, again as if nothing had happened, spent several months without air. Now there was no longer any doubt that frog skin is a versatile device that can make you blacken with the envy of even the most diving divers. Still, to be able to extract oxygen directly from water!
Related article Real frogs (Ranidae)
But the curtain was not raised over all the secrets of frog skin. Its smooth, silky surface begs to be stroked, but this is perhaps not worth doing. The fact is that it is covered with a poisonous protective mucus - for what else can the poor frog defend with? If this mucus is injected into birds, they die of respiratory paralysis. The Asian tree frog secretes poison that can cause paralysis in small animals, and the tiny frog of tropical America supplies the local Indians with poison that is equally deadly to humans, monkeys and jaguar.
It seems that no one will be tempted to stroke a frog. And would she even feel the touch? The ease with which the frog tolerates skinning has long led researchers to believe that its skin is just a bag, not connected with surrounding tissues. Error: Ligaments exist as septa separating the lymph sacs. These bags can fill with water, and then the frog, as in the fable, swells to such a size that it risks bursting.
Face the light. The owner of the skin periodically frees itself from it and immediately bites it, unless the tribesmen outstrip it.
Molting allows the frog to renew its natural color. Her modest green soul warmer takes in turn almost all shades of the rainbow - from bright green to turquoise blue or black, from yellow to white and brown. All this is the work of special cells that create certain color combinations depending on temperature, light, humidity and emotions. Color change - a salutary mimicry - allows it to completely dissolve in the environment.