Evolutionary Reasons for Male Preferences Regarding the Female Breast Shape

Sir:

Plastic surgeons have considered a certain type of breast as ideal for many years. However, there is little discussion in the plastic surgery literature regarding why this specific type is aesthetically pleasant. Other fields, such as evolutionary biology, might have the answers to this question. Many studies have shown the importance of facial symmetry and waist-to-hip ratios to determine beauty and its applied expression: mate preferences.¹ However, the reason why a nonptotic, round, symmetrical breast is considered as ideal is unknown. The currently accepted main hypothesis regarding mate preferences is based on a modern genetic and psychological approach to evolutionary theory.² This hypothesis states that males and females will both seek qualities in mates that will best increase their reproductive success. Because of sex differences in the constraints on reproductive success, men and women will value different characteristics. Women invest more heavily in fewer offspring and have sharp constraints on quantity.^2,3 The primary constraint on a man’s reproductive success is access to fecund and reproductively active women. Because relative youth and physical appearance provide strong cues to fecundity and reproductive value in women, men are known to value them in potential mates.^2–4 Cues that are observed suggesting that a woman has diverted that availability to another man should be disfavored. Because of the unique human cryptic female ovulation phenomenon (men cannot tell when the human female is in estrus), men cannot determine if a recent female mate is bearing someone else’s child.² The evolutionary solution for this problem was the strong male preference for young and nulliparous women. This preference is strongly evident cross-culturally and is considered as not being related to cultural influences.

Unfortunately, for men, reproductive value and nulliparity are not attributes that can be directly observed. This raises a crucial issue in the evolution of mate preference mechanisms of men being able to reliably identify female attributes that are correlated with reproductive capacity and nulliparity. Standards of female beauty have evolved to correspond to relative reproductive value (expected number of future offspring) or fertility (probability of current conception).^2–5 In this communication, we hypothesize that the male (and secondarily female) preference for nonptotic, symmetric breasts reflects a strong preference for nulliparous and fertile women, and this has evolved to simulate such a condition. The postpregnancy breast shape is a major sign of previous child bearing (Table 1). In fact, this may be the only visual sign of previous pregnancies. Evolutionarily speaking, men with a preference for the “nulliparous breast shape” would have had more reproductive success. There has been a lot of discussion regarding how to change breasts shape to make them the way we like (Fig. 1). Evolutionary psychology can help us find out why we like what we like. It may be romantic to think that plastic surgeons have an artistic and intuitive feeling regarding the most appealing breast shape. But ultimately it is all biology, as evolutionary psychology is starting to show us.

Table 1.

Main Breast Changes after Pregnancy

Fig. 1.

A, C, Typical post pregnancy breast shape. B, D, After mastopexy with silicone implants.

DISCLOSURE

The author have no financial interest to declare in relation to the content of this article. The Article Processing Charge was paid for by the author.

Filipe V Basile, MD
Department of Plastic Surgery
Basile Medical Center
São Paulo, Brazil