Acquired morphological changes of mammalian hair scales

Abstract

The original and postnatal scale patterns of guard hairs were compared. The comparisons illustrate that acquired morphological changes take place in the scales on the coarse section of guard hairs. Scales on this part changes from regular smooth to irregular wave. The primary reason would be friction. Scales on the lower part of guard hairs are thick and strong to bear friction. Additionally, they are berried in the bottom layer of pelage where friction is avoided. Scales on the coarse section are thin, broad, dense and overlap, and exposed in the environment as a cover of pelage. So friction always happen on them. Factors which enhance coefficient of friction and weaken keratin bonds are combined to damage hair scales. The results suggest that regular smooth and irregular wave are actually the same type exhibiting the same origin morphological characters, so they should be counted together in the species identification.

Keywords

Hair scale / Scale damage / Species identification / Acquired morphological change