Evolution of the foreskin: Difference between revisions

 
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== Evolution ==
== Evolution ==
===Natural selection===
===Natural selection===
Charles Darwin (1859) has done an admirable work in introducing the principle of ''natural selection'' to explain evolution.<ref>{{REFbook
[[Charles Darwin]] (1859) has done an admirable work in introducing the principle of ''natural selection'' to explain evolution.<ref>{{REFbook
  |last=Darwin
  |last=Darwin
  |first=Charles
  |first=Charles
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=== Morphology ===
=== Morphology ===
The [[prepuce]] has been well conserved by evolution.<ref name="cold-mcgrath"/> In primates, the [[foreskin]] has been present in the genitalia of both sexes of mammals for at least 65 million years and likely has been present for over 100 millions years of evolution, based on its commonality as an anatomical feature in mammals.<ref>{{REFbook
The [[prepuce]] has been well conserved by evolution.<ref name="cold-mcgrath"/> In primates, the [[foreskin]] has been present in the genitalia of both sexes of mammals for at least 65 million years and likely has been present for over 100 million years of evolution, based on its commonality as an anatomical feature in mammals.<ref>{{REFbook
  |last=Martin
  |last=Martin
  |first=Robert D.
  |first=Robert D.
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  |pubmedID=8771059
  |pubmedID=8771059
  |pubmedCID=
  |pubmedCID=
  |DOI=10.1016/0306-9877(95)90248-1  
  |DOI=10.1016/0306-9877(95)90248-1
  |date=1995
  |date=1995
  |accessdate=2024-12-22
  |accessdate=2024-12-22
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  |date=1990
  |date=1990
  |accessdate=2024-12-22
  |accessdate=2024-12-22
}}</ref> The human [[penis]] has retained and modified its prepuce over a period of extraordinarily evolution.<ref>{{REFjournal
}}</ref> The human [[penis]] has retained and modified its prepuce over an extraordinary period of evolution.<ref>{{REFjournal
  |last=Dixson
  |last=Dixson
  |init=AF
  |init=AF
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[[Image:Rhesus-Monkey-&-Human-Penis.gif]]
[[Image:Rhesus-Monkey-&-Human-Penis.gif]]


The rhesus monkey has fewer corpuscular receptors in the prepuce (foreskin) and more corpuscular receptors in the glans (head). In humans, however, the [[glans penis]] has few corpuscular receptors and predominant free nerve endings,<ref>{{REFjournal
The rhesus monkey has fewer corpuscular receptors in the prepuce (foreskin) and more corpuscular receptors in the glans (head). In humans, however, the [[glans penis]] has few corpuscular receptors and predominant free nerve endings,<ref name="halata1997">{{REFjournal
  |last=Halata
  |last=Halata
  |first=
  |first=
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  |accessdate=2024-12-22
  |accessdate=2024-12-22
}}</ref>
}}</ref>
<ref name="halta86">Halata, Z, & Munger, B. (1986). [https://d1wqtxts1xzle7.cloudfront.net/47139534/0006-8993_2886_2990357-420160710-21337-1czck3b-libre.pdf?1468265379=&response-content-disposition=inline%3B+filename%3DThe_neuroanatomical_basis_for_the_protop.pdf&Expires=1734892546&Signature=O~Vq~9NOh5xvfzPrJW4djV0J10wBmjXpWzur15ePWMk3JdOLkzQzgojJ2LCa3gic-AbH2aMoAXz69A917N6mz-SEK5sHcaLXV0ErNuukCgDx-pGv2VIkGc2fSAF349SNap8Q~I7hejjIxeAu0jUQAfAbPye9XhNicmpCxEgsC~esFLs~pmEL9iUu-7hjxEk0XlANYkgZgDlqD5D3W7v4lMwDy5EWDm5Q4dNdDpmj0vlFomHt3SBXkjlkFp6e7L-AFtaenKaEgLUZ~RYC5IylmO58vdCIlUFme4-AVlK7iSPDr0NlA0hC2w8ThUEVt0BORntmbVxt-OmJA2gXGD7nDw__&Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA The neuroanatomical basis for the protopathic sensibility of the human glans penis]. Brain Res, 34(506)</ref> consistent with protopathic sensibility. Protopathic simply refers to a low order of sensibility (consciousness of sensation), such as to deep pressure and pain, that is poorly localised. The human glans penis has virtually no fine touch sensation and can only sense deep pressure and pain at a high threshold.<ref>Von, F.M. (1894). Beiträge zur Physiologie des Schmerzsinns. Akad Wiss Leipzig Math.-Naturwiss Kl Ber.</ref><ref name="macaca"/> While the human [[glans penis]] is protopathic, the [[prepuce]] contains a high concentration of touch receptors in the [[Ridged band|ridged band]].<ref name="cold-mcgrath"/>


In the human [[penis]], the [[prepuce]] is known to have ten times more corpuscular sensory receptors than the [[glans penis]].<ref name="halta86"/>
In the human [[penis]], the [[prepuce]] is known to have ten times more corpuscular sensory receptors than the [[glans penis]].<ref name="halata1986">{{REFjournal
|last=Halata
|first=
|init=Z
|author-link=
|last2=Munger
|first2=
|init2=BL
|author2-link=
|etal=no
|title=The neuroanatomical basis for the protopathic sensibility of the human glans penis
|trans-title=
|language=
|journal=Brain Res
|date=1986-04-23
|volume=371
|issue=2
|pages=205-30
|url=
|archived=
|quote=
|pubmedID=3697758
|pubmedCID=
|DOI=10.1016/0006-8993(86)90357-4
|accessdate=2024-12-22
}}</ref>


The male and female prepuce has persisted in all primates, which strongly supports the contention that the [[prepuce]] is valuable genital sensory tissue. The corpora cavernosa and the prepuce are the only two universally common characteristics of the primate penis.<ref name="cold-mcgrath"/>
The male and female prepuce has persisted in all primates, which strongly supports the contention that the [[prepuce]] is valuable genital sensory tissue. The corpora cavernosa and the prepuce are the only two universally common characteristics of the primate penis.<ref name="cold-mcgrath"/><ref name="macaca"/> While the human [[glans penis]] is protopathic, the [[prepuce]] contains a high concentration of touch receptors in the [[Ridged band|ridged band]].<ref name="cold-mcgrath"/>


=== Further reading ===
== Further reading ==
* {{REFbook
* {{REFbook
  |last=Denniston
  |last=Denniston
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}}
}}


[[Image:The-Descent-of-Man-and-Selection-in-Relation-to-sex.gif|100x130px]]
[[Image:The-Descent-of-Man-and-Selection-in-Relation-to-sex.gif|200x260px]]
[[Image:Primate_Origins_and_Evolution.gif‎|100x130px]]
[[Image:Primate_Origins_and_Evolution.gif‎|200x260px]]
[[Image:Perspectives_in_biology_and_medicine.gif‎|100x130px]]
[[Image:Perspectives_in_biology_and_medicine.gif‎|200x260px]]
[[Image:America_Journal_of_Primatology.gif‎|100x130px]]
[[Image:America_Journal_of_Primatology.gif‎|200x260px]]
[[Image:Studies_In_Neurology.gif‎|100x130px]]
[[Image:Studies_In_Neurology.gif‎|200x260px]]
[[Image:Why_Sex_Is_Fun.gif‎|100x130px]]
[[Image:Why_Sex_Is_Fun.gif‎|200x260px]]
[[Image:Mothering.gif‎|100x130px]]
[[Image:Mothering.gif‎|200x260px]]


=== Videos ===
== Videos ==
==== Functions of The Foreskin - Part 1 ====
=== Functions of The Foreskin - Part 1 ===
<youtube>http://www.youtube.com/watch?v=r9DoCn3gATE</youtube>
<youtube>http://www.youtube.com/watch?v=r9DoCn3gATE</youtube>


==== Functions of The Foreskin - Part 2 ====
=== Functions of The Foreskin - Part 2 ===
<youtube>http://www.youtube.com/watch?v=Ps1dkbcOKfA</youtube>
<youtube>http://www.youtube.com/watch?v=Ps1dkbcOKfA</youtube>
{{SEEALSO}}
{{SEEALSO}}
* [[Foreskin sensitivity]]
* [[Foreskin sensitivity]]
* [[Penis]]
* [[Penis]]
{{LINKS}}
{{LINKS}}
* * {{REFweb
* {{REFweb
  |url=http://www.intactaus.org/information/functionsoftheforeskin/
  |url=https://intactaus.org/information/functions-of-the-foreskin/
  |title=Functions of the Foreskin
  |title=Functions of the Foreskin
  |last=Helard
  |last=Helard
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  |quote=
  |quote=
}}
}}
{{REF}}
{{REF}}