Evolutionary Biology

, Volume 37, Issue 2–3, pp 113–122 | Cite as

The Evo-Devo Puzzle of Human Hair Patterning

  • Lewis I. HeldJr.Email author

Humans differ from all other living primates in the sparseness of our hair. Even more puzzling than the overall reduction in our fur covering is the layout of the few tufts that remain. Why does hair grow mainly on our scalp, armpits, and groin? How does our genome designate these areas? Clues to the underlying mechanism can be found in mouse mutants and human syndromes, but the mystery remains essentially unsolved. This essay reviews the evidence, pieces together the clues, and formulates a tentative hypothesis in the style of a Sherlock Holmes story. The deductive reasoning of the narrative is aided by what we already know about an analogous locus in the fruit fly that performs a comparable function.

Homo sapiensare the only “naked apes,” though this phrase, popularized by Desmond Morris, is somewhat misleading. We still have a profusion of hair on our scalp and, as children, the rest of our body makes a fine, transparent “peach fuzz” called vellus. Indeed, the only truly hairless...


Scalp Hair Area Code Hypertrichosis Master Gene Hypotrichosis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Iterated drafts of the manuscript were kindly critiqued by David Arnosti, Tom Brody, Jason Cooper, Nancy McIntyre, Jeff Thomas, Kenneth Weiss, and Adam Wilkins. Encouragement was provided by Benedikt Hallgrímsson. Matt Hoffman, a primate expert at the University of Wisconsin, helped me locate dozens of photos of newborn apes. Finally, I thank all of the zoo personnel around the world who responded so unselfishly to my requests for pictures and data.


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Authors and Affiliations

  1. 1.Department of Biological SciencesTexas Tech UniversityLubbockTXUSA

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