A Study On The Functional Adaptability Of The Morphological Structure Of Weasel's (Mustela Sibirica) Hair

In this paper, the research material was fur from 30 yellow weasels (Mustela sibirica) which were sampled from Longko Forest Farm of Tonghe in Xiaoxingan Mountains in winter, 15 males and 15 female respectively. The area of the weasels fur were measured, and four types of hair were sampled from different parts of the weasel including head, back, belly, buttocks, middle tail, upper part of foreleg and hind leg, lower part of foreleg and hind leg, 5 hairs of each type at every part, meanwhile, 5 upper hairs were sampled from forepaw and hind paw respectively. All the sampled hairs were made into cuticular impression organic glass and medulla pattern slide. According to the study guideline of structure-function-adaptation combination, all types of hair from all the sampled parts were measured for indexes including the length of hair, medulla and non-medulla tip, the diameter of hair and medulla, the length of different types of scales, additionally pin-hair from the back and the upper hair from paws were measured for the diameter of hair root and the length of hair follicle by using scanning electron microscope photographing, biological microscope and its supporting software for photo processing and measuring. Then the proportion of medulla length to hair length, length of non-medulla tip to hair length, medulla diameter to hair diameter, and length of different types of scale were calculated respectively. By using software SPSS, statistical analysis for indexes above were carried out and the conclusions were as following: (1) the body size and the growth match of four hair types is of great significance for the weasel's adaptability. (2) On the precondition that enhancing the function for heat preservation and mechanical injury resistance, the indexes of Siberian weasel's hair has an obviously functional differentiation according to the different function focus of different parts of the body. (3) The special structure of upper hairs from weasel's paws, where the medullary index is lower, the hair diameter is thicker and the length of hair follicle is longer, is of great significance for mechanical injury resistance.(4) Imbricate scales of upper hairs from the end of weasel's limb are stronger than those from the main body so that enhance the function of mechanical injury resistance for the hair fibers.(5) For the weasel, functional differentiation of these indexes is not isolated; the function of hairs from same part is consistent. (6) The characteristic of Siberian weasel's hairs and body is of great significance for the adaptation to environment, which is a result of natural selection during the long-term evolutionary process.