General explanations concerning about fluctuation phenomena which widely exist in nature, classification of the fluctuation and characteristics of all kinds of fluctuation spectra were given in this article on the basis of achievement in modern wooden material environmental science. This article focused on characteristics of the fluctuation spectra of wood structure and creature physical rhythm. According to their common point, which is the relativity between the two fluctuation spectra, the author represented some superficial illustrations and pointed out the reason why people are so fond of biological material——wood and woods grain structure from ancient time.