Differences Between Human & Animal Hair

Numerous differences exist between human and animal hair. Some are obvious to casual observers, while others usually only are considered by scientists. Differences occur in hair between various animal species as well.

Significance

Knowing the differences between human and animal hair and various species of animals is important in forensic science, as hair may be important for criminal investigations. It also is important for companies manufacturing shampoos and other grooming products for household pets.

Growth

Strands of human hair normally grow and fall out independently, and the hair must be cut to retain a certain length. The hair of animals, in contrast, stops growing at a certain length, and large amounts commonly fall out (shed) and grow back at different times of year.

Sensory Hair

Animals have tactile hairs that provide sensory functions, commonly called whiskers. Humans do not have these hairs. Human whiskers simply refers to hair that grows on the lower part of the face.

Identification

Specific humans can be identified by an individual hair. Specific animals, however, cannot, because their hairs do not have enough individual microscopic properties.

Texture

Animals typically have a short fine layer of hair under a coarser top layer. This composition keeps water from soaking through the hair and also helps maintain proper body temperature in cold and heat.

Misconceptions

The hair of animals is commonly called fur, but there is no technical difference between hair and fur.

References

• FBI Forensic Science Communications; Microscopy of Hair: A Practical Guide
• FBI Forensic Science Communications; Hairs, Fibers, Crime, and Evidence