Evolutionary Relic or Functional Organ?
Men have nipples because of the wayembryosdifferentiate duringgestation(the period between conception and birth).
Research studies sometimes don’t use the terminology in this way.
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Fetal Development
The answer is simpler than you think.
Nipples are already developing at this time.
Both sexes have one X chromosome.
A second X chromosome defines a female.
An additional Y chromosome defines a male.
This pit will gradually form a depression that connects to a lactiferous (milk-producing) duct.
While this happens to some degree in males, it is far less profound and developed.
They may be more accurately described as remnants of fetal development.
But even this suggests that male nipples serve no real purpose.
The stimulatory response in males (and females) seems to be unique to the human species.
It could potentially have evolutionary value in that it contributes to the desire to reproduce.
Some are the result of the dysregulation of hormones, while others may be due to genetics.
Gynecomastia can also affect boys and younger males.
In some cases, particularly in adolescent boys undergoing puberty, the condition is temporary.
Summary
Males have nipples because of the way that embryos develop in the initial weeks after gestation.
Nipples begin to develop before that time.
Like the appendix and wisdom teeth, male nipples are widely assumed to be functionless.
Male nipples tend to end up being smaller than female nipples.
There is also less variation among male nipples than female nipples.
For around half of men, the nipples are an important erogenous zone.
Some research suggests nipple stimulation fires up areas of the brain related to genitalarousal.
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