Forensic Crime Scene Eisenhower High School Animal Hair Forensic Crime Scene Eisenhower High School
Animal Versus Human Hairs Human hairs are generally consistent in color and pigmentation throughout the length of the hair shaft, whereas animal hairs may exhibit radical color changes in a short distance, called banding. The pigmentation of human hairs is evenly distributed, or slightly more dense toward the cuticle, whereas the pigmentation of animal hairs is more centrally distributed, although more dense toward the medulla.
Animal Hairs animal hairs do not possess enough individual microscopic characteristics to be associated with a particular animal to the exclusion of other similar animals If the questioned hair exhibits the same microscopic characteristics as the known hairs, it is concluded that the hair is consistent with originating from that animal
To distinguish between animal and human hair use a Medullary Index diameter of hair’s medulla Medullary Index =------------------------------- diameter of the hair M.I. = <.33 hair is human M.I. =>.5 or more, hair is animal
Appearance of different hair (or fur) types will vary from animal to animal
Cat hair
Cat Hair bsapp.com
Dog hair
Dog Hair bsapp.com
Rabbit hair
Rabbit Hair bsapp.com
Horse Hair bsapp.com
Mouse Hair bsapp.com
Deer Hair bsapp.com
Cow Hair bsapp.com
Pig Hair bsapp.com
Bat Hair Hair
Can you identify the animal hairs shown? B C D G E F H I Teacher Note: I challenge students to identify each hair sample pictured on this slide as they examine the sets of animal hairs I have prepared for them. An observation worksheet is available on my website which requires students to draw an image of what they see and add a description that highlights unique characteristics of each specimen. A key for the animal hairs is available on the next to last slide of this presentation! Think About It … In which samples are we viewing the cuticle? How do they compare? (2) In which samples are we viewing the medulla? How do they compare? (3) What characteristics can be used to identify hair samples?
Types of Animal Hairs - Key Cat Horse Pig Human A B C D G E F H I Deer Dog Rabbit Rat Human