Trace Evidence
Defined as materials that could be transferred during the commission of a violent crime, trace evidence consists of multiple sources of which include hair, fibers, soil, gunshot residue, among many more. Trace evidence can be transferred between people, objects, or the environment during the commission of a crime (Federal Bureau of Investigation, 2016). This idea is known as the Locard exchange principle which is the idea that whenever someone makes contact with an item, person, or location physical evidence is either taken or left behind. The evidence is then collected and analyzed where investigators can theoretically establish that a victim and a suspect were in the same area (National …show more content…
Each one has their own area of focus as evidence when in a forensic investigation. Human hairs, already briefly discussed, are uniquely distinguishable from animal hairs. Animal hairs are broken down into three basic elements (1) guard hairs, from the outer coat of the animal, which is used as protection, (2) the fur or wool hairs that form the inner coat and provide insulation, (3) tactile hairs, or whiskers, that are found on the head of an animal to provide sensory functions (Koch & Deedrick, 2004). Hairs found on the animal’s tail can be a modified combination of both guard hairs and fur …show more content…
Human hair usually has pigment throughout the entire length of the hair shaft; however animal hair has exhibits radical color changes in patterns. The density of animal hair is often thicker, larger in overall diameter and occupies more area than in human hair. The root of human hair is frequently club-shaped, although the roots of animal hairs can be of various shapes, depending on the animal species (Koch & Deedrick, 2004). One of the main variances between human and animal hair is within the core of the hair follicle. For animals, the core allows for the hair to provide significant insulation as well as protection from environmental elements. Whereas the human hair does not have the ability to provide any form of temperature regulation for the human body (Koch & Deedrick,