Animal sappers. part 3
Even better suited to the bombing business, the badger. His body is long and strong, his legs are short and his front claws are rounded at the ends; his feet are as wide as shovels, his toes are not very mobile, which also facilitates digging. Tearing the ground, the badger acts with the front legs, and when the dug ground begins to interfere with the work, he starts to use his hind legs, throwing them back the ground with great force. When there is too much earth behind him, he backs away and pushes the entire back of his body to the surface.
The badger's den is an entire structure: the central room is located at a depth of about 2 meters and from it goes up to 4-8 moves 6-8 meters long. In normal time, however, badger uses only 2-3, the rest serve as vents or spare passages in case of danger. Movements are made badger very clean and neat, and in the hole reigns purity and order.
Badger is already to a certain extent tied to underground food and the way of eating. He digs out all sorts of roots, eats underground larvae of insects and earthworms, tears the nests of earth bumblebees and wasps. Even more tied to the ground rodent sappers, which is almost a large half of this family. Pestrushki, or lemmings, of the far north, field mice of all genera, rabbits, finally, gophers, hamsters, and alpine marmots - are increasingly engaged in engineering. This is not surprising! All these are defenseless animals, unable to run fast and at the same time, tied to vegetable food. Underground existence guarantees them life and, at the same time, allows them to find plenty of food.
The most perfect rodent engineers are the so-called steppe dogs - gopher-like animals found on the prairie of Louisiana. In some places, the steppes are dotted with the hills of the earth in front of the entrances to the underground dwellings of steppe dogs, and the animals themselves appear in the twilight on these hillocks, stretching out in a string like sentry ones. Their moves sometimes are the source of the earth, and it is impossible to take a step not to fall into the underground gallery with your foot.
It would seem that life in the air layers, constant sunlight bathing is completely incompatible with the existence in the dark dungeons! How can a creature accustomed to complete freedom, to fast, graceful movements in the air, tie himself to a dark, cramped grave?
Meanwhile, it is one of the best fliers, in the struggle for life and for the welfare of their offspring, doom themselves to voluntary confinement in the underground kingdom during the whole time of hatching eggs and feeding the chicks. These are the coastal swallows, or swifts (Cotyle), that we see all over the riverbanks and sandy cliffs.
The blasting abilities of these small birds are directly striking and are related to the special structure of their limbs: the middle and outer toes of the legs are connected and form a kind of small spatula. In two or three days a pair of swallows perform a gigantic work: with their weak beak and feet, they dig an underground gallery 5-8 centimeters in diameter and sometimes 2 meters in length. At the back end of the gallery expands, and there is a nest.
It should be noted that the wings give birds of prey a huge advantage over four-legged sappers: they can lay the beginning of the gallery on a completely vertical cliff, on which predators are unable to rise or fall. This makes the swallow's habitat completely inaccessible.
Many experienced sappers we meet among the lower animals - because the laws of life and living conditions are the same for the entire animal kingdom!
Among the insects one of the best engineers is a bear - not without reason the French call it a "mole-cricket". It is, in fact, on its long body, short legs and, in particular, on its spade-shaped extremities with huge teeth, as if fingers, resembles a mole. Surprisingly, it is also covered with a thick velvety cover of short hairs, - a complete resemblance to the mole with his velvet skin. Of course, this is not an accident, but also an adaptation to the general conditions of existence. After all, such short hairs, forming a thick velvet, perfectly protect the surface of the body from clogging the ground, thrown out when digging. Particles of the earth falling on the hairs, thanks to the elasticity of the latter, are dropped and do not block - in one case - the skin glands, in the other - the spiracles and legs. to be continued in the next part