Soil fitness traits?

1. Small size to be able to fill the spaces between soil particles;
2. Ability to breathe with the entire surface of the body and assimilate oxygen, which is dissolved in water;
3. For large animals – powerful limbs with which it is possible to break through the passages under the ground;
4. Excellent sense of smell, but poor eyesight;
5. Dense, compressed body. If there is fur, then it should fit snugly to the body;
6. The life cycle of an inhabitant does not require moisture and light.