Ultramicroscopic observations on morphological changes in hair during 25 years of weathering.

Weathering or long-term burial may cause profound morphological and histological changes in hair, which may affect the results of forensic and archaeological investigations. We therefore used ultramicroscopic techniques to assay the changes in weathering hair shafts caused by burial for up to 25 years. We found that the middle portion of hair shafts from living individuals shows the expected histological hair structure, while the cuticle layer was absent from the terminal portion of the same hairs, which may be due to the increased weathering experienced by the terminal portion.