In humans, terminal hair is a variant of hair that is thick and long such as that growing on the scalp, as compared with

vellus hair Vellus hair is short, thin, light-colored, and barely noticeable hair that develops on most of a human's body during childhood. Exceptions include the lips, the back of the ear, the palm of the hand, the sole of the foot, some external genital ...

, colloquially known as peach fuzz, growing elsewhere.Marks, James G; Miller, Jeffery (2006)
''Lookingbill and Marks' Principles of Dermatology''
(4th ed.), Elsevier Inc., p. 11. During

puberty Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a female, the testicles i ...

, the increase in androgenic hormone levels causes vellus hair to be replaced with terminal hair in certain parts of the human body.Hiort, O. "Androgens and Puberty". ''Best Practice & Research Clinical Endocrinology & Metabolism'', Vol. 16, No. 1, pp. 31–41. These parts will have different levels of sensitivity to androgens, primarily of the testosterone family.Neal, Matthew; Lauren M. Sompayrac
''How the Endocrine System Works''
Blackwell Publishing, 2001, p. 75. The pubic area is particularly sensitive to such hormones, as are the armpits which will develop axillary hair.Randall, Valerie A.; Nigel A. Hibberts, M. Julie Thornton, Kazuto Hamada, Alison E. Merrick, Shoji Kato, Tracey J. Jenner, Isobel De Oliveira, Andrew G. Messenger. "The Hair Follicle: A Paradoxical Androgen Target Organ", ''Hormone Research'', Vol. 54, No. 5–6, 2000. Pubic and axillary hair will develop on both men and women, to the extent that such hair qualifies as a

secondary sex characteristic A secondary sex characteristic is a physical characteristic of an organism that is related to or derived from its sex, but not directly part of its reproductive system. In humans, these characteristics typically start to appear during pubert ...

,Heffner, Linda J. ''Human Reproduction at a Glance''. Blackwell Publishing, 2001, p. 33. although males will generally develop terminal hair in more areas. This includes facial hair, chest hair, abdominal hair,

leg A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element cap ...

and arm hair, and foot hair.Robertson, James
''Forensic Examination of Hair''
CRC Press, 1999, p. 47. Human females on the other hand generally retain more of the vellus hair.Neal, Matthew; Lauren M. Sompayrac. ''How the Endocrine System Works''. Blackwell Publishing, 2001, pp. 70, 75. These hairs are present in the large apes but not in the small apes like gibbons and represent an evolutionary divergence.

References

{{Human hair Hair anatomy

See also

References