Hair Microscopy A Novel

What is hair anyway?  Primarily composed of the protein keratin  Can be defined as slender outgrowths of the skin of mammals  Hairs can be transferred during physical contact, so their presence can associate a suspect to a victim or a suspect/victim to a crime scene.

Hair Characteristics  Macroscopic  Length  Color  Shape (curly vs. straight, etc.)  Microscopic  Root appearance  Pigment distribution  Shape

Varieties of Hair on a Mammal  Humans  Head  Pubic  Arms/Legs  Beasts  Coarse,outter guard hairs  Fine fur  Tactile hairs (whiskers)  Tail/Mane hairs

Hair Life Cycle  Anagen  Growth stage  At any time, 80-90% of hair is in anagen on a human head  Catagen  Tranistion stage from anagen to telogen  Telogen  Dormant, resting phase  Hairs in this phase fall out readily with a comb or light contact  10-18% of hair on a head is in telogen

Naturally Shed Hair  Hair dislodged by combing or other light contact  Root is undamaged  Club shaped

Ouch! Forcibly Removed Hair  Hair is bent and/or broken  Root shows damage and stretching (top)  May have scalp tissue still attatched (bottom)

Animal Hair!  Animal hair is very useful for placing a suspect/victim in a location, as they are easily transferred by clothing  Cat or dog hairs have been found on the adhesive portions of ransom notes!  Secondary transfers also occur  Animal hairs can used to identify species or breeds, but not individuals

Razor Cut hair

Split Hair

Hair with cut tip

Buckling

Burnt Hair

Race - Caucasoid

Race - Negroid

Race - Mongoloid