What does the morphology of hair tell forensic scientists

Historically, hair has been considered class evidence because a hair specimen could not be identified with certainty as having originated from a particular person. A forensic scientist who studied the morphology (shape, form, and structure) of a hair specimen could testify as to the gross physical characteristics of the hair (color, degree of curl, etc.), its internal and external structural characteristics, the likely somatic region from which the hair originated (scalp, beard, pubic, axillary, etc.), and-at least for scalp hair, and often for pubic hair, the probable race of the person from whom the hair originated. But all of those are class characteristics rather than individual characteristics, so the most the forensic scientist can state based on morphological examination is that a hair specimen is "consistent with" or "similar in all respect to" another specimen.