The analysis of hair is a very useful tool for forensics. Any remaining hair can be studied and one can determine the type of animal it came from. In this lab we compared dog, cat, and human hair. The dog hair tended to be thicker and had diagonal lines going down the hair. The cat hair was very thin and had straight lines that went parallel along the hair. The human hair was semi-transparent and had crack-like lines on it. This information can be used to determine the species of animal that an unknown hair came from. We also compared hair from a husky to that of a lab and we were still able to see differences, although it was more difficult. Hair can also be linked to a specific through DNA. Unique, nucleic DNA can be found in the root of the hair and mitochondrial DNA, which is less unique, can be found in the shaft of the hair. This lab also taught me a lot about the structure of hair. The medulla is the inside core, the cortex surrounds the medulla, and the cuticle is the final layer on the outside of the hair. These three parts vary in certain characteristics and can therefore be used to identify unknown hairs. This large amount of variation in hairs makes it a very useful tool for forensics.