Do male nipples have a biological function?
959761
Yes, it does.\n\nIt is meant to be a thermometer.\n\nWhen its cold it becomes hard and pointy.
925241
It can happen if hormone mix and stimulation is set to allow it, but I don't think they commonly do.\nAnd contrary to what the other guy said, the glands *are* there in males, just dormant.  There have been cases where non-transgendered men started lactating, usually because something in the environment was messing with their hormone levels.
962912
you should read the book why do men have nipples.  it askes a similar question and a doctor answers it.
392368
Men's nipples don't have a purpose.  When a baby is developing in the uterus, they all start out as female, hence the nipples developing.  Basically in order for a male to develop from there is a genetic fluke which sends signals to start developing male organs.  The only sign that is left that all men started as females at the most basic level of life is the nipples.\n\nFascinating, huh?
901284
Some guys have larger areolas [the "red circles"], as they range from very small to large.  Nipple sizes on guys vary, too.  Usually gynecomastia refers to the actual breast area.... refer to the link below, as it has some information that you may find useful and informative.
707294
Penis and nipples in male\nClitoris and nipples in female\n\nThere is also erectile tissue in the nasal passages\nof both males and females. REALLY!\nThis accounts, in part, for the heavy breathing during\nsexual arousal.
86011
Males also have the hormone estrogen. Estrogen menlarges breast size. Women have more of it, so they have bigger breasts. They also have luteniezing hormone which produces milk for mammary glans after giving birth. Men do not have that. Women displaying male qualities like beards have an excess of testoserone and androgen
453787
"Both male and female adolescents may experience a milky discharge during puberty. Nipple discharge in the adult male is more often associated with a malignant condition than in the female. Mammography should be performed and biopsy should be performed if a mass or mammographic abnormality is found."\n\nhttp://www.imaginis.com/breasthealth/nipple.asp\n\n"Both male and female adolescents may have milky nipple discharge during puberty."\n\nhttp://www.breast-medicine.com/nipple_discharge.htm
391059
Marriage doesn't make any difference to the appearance of nipples.  I used to think that nipples had one tiny hole in the middle somewhere.  I got a surprise the first time I nursed.  The nipples have lots of little holes like a garden watering can.  The holes are so little you can't see them.
264259
The reason is a mix of physiological responses. However primarily the nipple's purpose is to provide milk to a potential infant. So, following this line of thought one can speculate that even if you were to consider it an erotic response, underneath it all it is just a physiological reaction to allow a potential infant to find its source of food. Crazy isn't it? Also here's something I found from Wikipedia.org - \n\n"Stimulation or sexual arousal can cause the nipples to become erect. Breastfeeding or exposure to cold temperatures often have this effect as well. Pregnancy and nursing tend to increase nipple size somewhat, and this increase may remain permanently thereafter. Small non-striated myocytes (muscle cells) arranged cylindrically within the nipple are responsible for this erection of the nipples."
754531
Your breasts are made of fat, skin, muscle and milk ducts, and other assorted things (like tubes to connect your milk ducts to your nipple, blood vessles, lymph nodes, etc)\n\nIn fact a male breast is made up of the same thing.\n\nMale and female babies can be born lactating because they are exposed to their moms hormones.\n\nSo you do not have breastmilk in your breasts but you are capable of making it if your hormones tell you to.
1052965
Men are XY, women are XX, right? The only genetic difference between men and women is whether they have a Y sex chromosome or not. Sexual characteristics such as genitals and breasts are encoded on the X and Y chromosomes, but NOT NIPPLES. Nipple genes are not on the X or Y chromosomes so we all have them. Women have genes in their XX genome to build mammary glands beneath their nipples -- men don't.
1183966
For modesty, to keep men from being turned on all the time.  A lot of men stare at at a woman's breasts instead of looking at her face when talking to her.  Even if they don't keep staring, that is usually the first thing a man looks at when looking at a woman.  So we are doing the world a great favor by keeping our nipples covered!  Not much work would get done by men if they saw nipples everywhere!
734061
Men don't develop breast tissue, but they do have nipples.  All humans at one point in time are a woman.  It all depends if the Y chromosome is present or not.  If it is, the body sends out testosterone changing the woman to a male.  The organs "down there" change to male organs, but the nipples just stay where they are.  So in a sence, men have nipples because women have them.
539202
Men have nipples. That is just part of human anatomy for males and females. \n\nAs for beards, that is also part of our biology. Men\nhave testosterone hormone which increases their hair growth at puberty and then into manhood.\n\nSome woman with high testosterone levels also have hair growth on face, for which most use some form of hair removal creme or other method\n\nBeards are a mans preference. My husband loves to groom himself with different face fashions  mustache, gotti\nsideburns, sideburns that frame chin. \n\nHave you ever seen a really long mustache. I wonder about\nthose\n\nI know for years its been part of men and fashion statement.\n\nHow about those long long beards like zztop, very funky.\n\nBluebeard, Jesus Christ,  Saints, Monks, Pirates, Rock Stars, Johnny Depp in the Pirates of the Caribbean (oooh)The bearded lady at the circus. \n\nuh oh, i'm going off now. \n\nBeards. They feel fuzzy and scrape your face when he kisses you. They can stimulate you when they rub up against your body. Hmmm. Think about that. They can make a man look \ndistinguished or unkempt. They can have things crawling in them if your not careful soooo WATCH OUT when you kiss the bearded men. And check out what happens when you pinch their nipples!
395112
Men have nipples b/c humans all come from a common ancestor.  And when we evolved, certain structures remained w/o a purpose.  This is refered to as having vesigal structures--a body part that has no function.  It is equivalent to hip bones in snakes and wing bones in dolphins.
11936
Somebody knows, ask an anatmoist. Nipples show up on a fetus before the fetus starts producing sex hormones (estrogen or testosterone). At this point in development the fetus is neither male nor female in appearance. Sex was determined at the moment the egg (X) was fertilized by a sperm (X or Y). This debunks the myth we all started female. As to why nipples develop so early, no one knows that answer.