Is the male variant of species an evolutionary modification of the female variant?

Jan 2, 2013


Discussion by: Timman
Is the male variant of species an evolutionary modification of the female variant? 

Preamble:
[References are available on request] The Anti-Müllerian hormone, (abbrev: AMH), is a glycoprotein hormone that in humans, is encoded by the AMH gene.It is secreted by the Sertoli Cells of the testes during embryogenesis of the fetal male

And also: 
(a)    Known to inhibit the development of Müllerian ducts in the male embryo.

(b)   Prevents the development of the Müllerian ducts into the uterus and fallopian tubes.

(c)    If no AMH is produced from the gonads, the Müllerian tubes automatically develop, while the Wolffian ducts, which are responsible for male reproductive ducts, automatically die.

(d)    The gene for AMH is located on chromosome 19p13.3.
      Another gene, identified, codes for it’s receptor on chromosome 12.(e)    In men, inadequate AMH activity can lead to the Persistent Müllerian duct syndrome (PMDS) in which a rudimentary uterus is present and testes are usually undescended.The genes mentioned above are usually found to be abnormal.     

(f) AMH is also present in fish, reptiles, birds and mammals. 

Debate
:
 Do the above facts suggest that the male variant of species is an evolutionary modification of the female variant?

Additional to this: Men possess rudimentary breast tissue, including aveoli and nipples.]In common terms: Does it imply therefore that without AMH, an individual will sexually develop internal female sex organs and be devoid of male sexual characteristics?

There are examples of natural cell apoptosis in the body’s immune system which can be accepted to exist for the purpose of regulating the immune system, (through the tumour necrosis factor receptor or other similar routes), but to actually have a naturally produced protein substance in vivo to cause cell death to prevent the existence of certain structures is somewhat mind-boggling. 

I am purposefully melodramatic here to entice a debate….another example of “The magic of reality?”
 
Yours sincerely, 
Dr.Pierre van der WaltMBChB
MMed(Chem.Path)
Chemical Pathologist,Private Lab. Practice
Pretoria,South Africa. 

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