Whatever gender we are or identify with, a woman (cis/trans), a man (cis/trans), a non-binary individual, we all have Nipples.
In early fetal stages, all embryo’s are equipped with nipples. After an embryo is conceived, it is kitted out to become either sex, male or female. This is called it’s Bipotential State. During the first six weeks, certain pre-organ structures are laid down, including two parallel milk ridges. Born of ancient genes and common to all mammals, these ridges run up and down the length of the torso. If the fetus inherits female XX genes and the process unfolds in the expected way, then oestrogen will turn the primitive plumbing into a female reproductive tract. If the foetus inherits male XY genes, testosterone will inhibit that progression. But the nipples remain. ( from ‘Breasts, a natural and unnatural history’ by Florence Williams)
The nipple is at the center portion of the breast, and in females is linked to the mammary glands where milk is produced during pregnancy. The areola is the darker colored area surrounding the nipple. The little bumps around your nipples are hair follicles, which both men and women have. (I have been plucking nipple hair since my teens).
Nipples can be flat, protruding, inverted or a combination of these nipple types. The size of women’s nipples apparently varies much more greatly between individuals than the size of men’s nipples. (Medical News Today 30June2018 By Maria Cohut).
Also the colour of nipple and areola can differ greatly. Although according to Jane Sharp, a 17th Century midwife who wrote the Midwives Book or the Whole Art of Midwifery, “Nipples are red after Copulation, red as a Strawberry, and that is their Natural colour”. (from ‘Whores of Yore’, a curious history of Sex).
Some people are born with two nipples on one areola, Bifurcated Nipple, and some have Supernumerary Nipples, a condition where further nipples have developed anywhere else on the body. Supernumerary nipples, and less frequently supernumerary breasts, seem to be present in about 1-5 percent of the population. These alterations are more common in women, usually occurring along the embryonic milk line, which extends from the axilla to the groin.
But then I read about a 22 year old woman, who had developed a well formed nipple with areola on the sole of her left foot, with proper breast tissue and all. Such unusual and rare cases of Supernumary breast tissue are also known as Pseudomamma, (from Dermatology Online Journal 2006 www.escholarship.org).
French Artist Claude Cahun seems to use the nipple as a device to question gender in the above image. Born Lucy Schwob in early 20th-century France, she decided to call herself Claude Cahun, in France a name which can refer to either a man or woman. Ambiguity was her tool, her way of exploring gender and sexual norms through her photography and writing. “Masculine? Feminine?” she wrote in one of her books,“It depends on the situation. Neuter is the only gender that always suits me”.