Underground body temperature is much lower than above ground, but the underground light has a special function, to say the least, strange, as long as leaving the surface into the bottom I never have hunger, even if I do not know how long or no feeling, subconsciously every cell of the body in the underground is more easily satisfied by light. On the nomadic journey from all kinds of holes into the underground is also a variety of biological neighbors to do one thing repeatedly, the next is each looking for something, I also unconsciously looking around looking.