Breasts are defined as secondary sex characteristics, so then why did breasts evolve?  Two main hypothesis’s exist in the anthropologists mind. The first is that men just favour women with larger breasts so that is who they mated with which lead to an increased breast size in our gene pool.  The second is that it was an evolutionary trait to attract men paralleled to the peacock and his eyelets on his feathers.  In peacocks studies have been done to show that the eyelets, both colour and quantity is a sign of the best possible mate to the Peahens.  These secondary sex characteristics have thus evolved into beautiful and ornate things of beauty.  So with this in mind it will be curious to see how “life finds a way” with all the plastic surgery and breast enhancements out there that actually skew reality.

Let’s say that men just really love women with large breasts and select those women to have sex with.  Well great, everyone loves boobs, and that would explain why breasts are getting larger, even unnaturally large in some instances.  Of course we have to balance in the additional hormone levels in our food, and our easy access to higher quality and more plentiful resources.  But what if it is the latter?

If women’s breast size was an adaptive advantage to securing a mate or even just getting his attention, it is possible that historically we were not all a monogamous society.  If women had to compete then there would have to be an evolutionary reason, and that reason just hypothetically would be that there was direct competition between the sexes.  Women had to display these secondary sex characteristics in the faces of men in order to be selected as a mate.  Thus there may have been a time when women had to compete for male attention in an evolutionary sense.  Likely to have evolved in multi female – one male societies as depicted in the animal kingdom where women needed to develop secondary characteristics.  We see examples in the animal kingdom where polygynous (one male, multi female)birds will develop very strong secondary sex characteristics to attract the males.  If interested this is a great article that explains further.  Although there is risk to utilizing animal behaviour to determine right and wrong human behaviours, it can be used and a great resource to exemplify the relationship variants. 

Personally I am far too competitive a soul to contemplate engaging in a plural relationship where I shared by mate full time with another female.  But that is entirely my viewpoint and I acknowledge that it may make some couples incredibly happy.   To me the fascination is in exploring all the different viewpoints and why as a society we favour one circumstance over another.  It’s exciting to think that we have evolutionary clues as to what and how our past ancestors lived, and under what social constructs.