Animal sappers. part 2
But where there are animals that feed on plants, they are followed by predators, for whom the "phytophages" are prey. Thus, underground life cannot be completely saved from the struggle for existence. This struggle under the ground is not as intense as on the surface of the earth, in the streams of sunlight.
Underground life and mining operations, which have to be carried out by underground inhabitants, cannot but leave a special imprint on their organization. Thus, in the conditions of underground life, a wide, thick body on high legs would be unprofitable: it would be necessary to spend a lot of extra work to dig a wide enough course - "with a large cross-section", as engineers would say.
In fact, the body of the sappers is usually long and narrow, on short legs, often spread apart. The front extremities must be adapted for digging, as the animal makes its way, and the hind legs must rake out and throw away the excavated soil. When digging an underground gallery, the head goes ahead of the limbs and must move into the ground like a wedge, which is why it is often stretched out in length and pointed, it is enough to remember the shape of the head of a badger and a phoenix. It happens that this wedge becomes hard, with great force driven into the soil: this is the origin of a kind of hornbeam of a duckbill and a huge, not commensurate with the size of the bird, the beak of a kingfisher! Both use their beaks to dig underground holes.
The shape of the front extremities of digging animals is often also very peculiar: we see in them as a combination of shovels, picks, and a rake - a combination, the most pronounced in the front legs of the mole. But isn't it wonderful that the same exact form is found in the front legs of the bear - an insect, of course, very far from the mole! The same goals and the same conditions often cause the appearance of extremely similar in its structure formations in no way related to each other living beings. This phenomenon, which is quite common in nature, is called "convergence".
It goes without saying that only such common features related to the same way of life are limited to the similarities between the sappers. They belong to various classes of the animal kingdom and are adapted to underground life to varying degrees.
Fox and fenek.
First of all, many of them are only temporary inhabitants of dungeons, who find protection during the day or only during the breeding and feeding of the younger generation. This category of animal sappers includes a number of predators digging complex holes with numerous passages.
The fox and its African relative, a fenek, are tied to the surface of the earth by the way of food extraction, and only spend a small part of their lives underground. Nevertheless, if the fox has the shortest legs and the longest and thinnest body (thanks to the fluffy fur, it seems thicker than it is actually), it is, of course, due to its presence in underground holes with numerous long and narrow passages.
However, the fox is a bad engineer: its front legs are weak and unarmed with long and thick claws, they are not spread out to the sides - in this respect, the fox is even superior to the dachshund. The fox's legs are rather adapted to running, and everyone knows that it is not so easy to catch up with them on a flat surface. Depending on its bad sapper qualities, the fox usually uses other people's burrows, most often badgers, and only adapts them to its use.
A more perfect sapper is an African fenek, but it should be said that the task is much easier for him - he lives in the sandy deserts, and he has to dig loose sand! Fenek digs masterfully," says one of the naturalists who have seen him in Africa, "he scrapes the ground so quickly with his front paws that it is difficult to follow their movement with his eyes. This dexterity often saves the animal's life, because when chasing fennel quickly buried in the sand, like an armadillo or a lizard. One day, accompanied by Arabs, I was chasing a fanek across the desert, who was running very close to us, but suddenly disappeared from our eyes. But I understood his trick, and this time it did not help him: I got off the horse, ripped the sand and pulled out of there alive puzzled animal, to the great joy of my companions. to be continued in the next part