Control of Paternity

In humans, elements of male-male competition, female choice, and male sexual coercion are present, suggestive of homologous characteristics with the Great Apes and a wider phylogenetic scope. Other features of human male behavior related to control of paternity appear derived. As an example of the latter, most of human male sexual coercion takes place within the early stages of or in ongoing partner relationships; consistent with male control of paternity, coercion such as beating or verbal abuse may increase the costs to a female of leaving a relationship or engaging in extrapair sexual behavior.

A host of tactics have arisen whereby human males enhance control over paternity and paternity certainty. As chronicled by various scholars (e.g., Wilson and Daly 1992; Potts and Short 1999), these include chastity belts in Europe and North America; female genital modifications ranging from removal of the labia minora to the clitoris to an extreme of infibulations involving sewing up the labial opening to prevent intercourse; cloistering women away from men; encouraging women to cover themselves extensively with veils or other forms of clothing; and encouraging foot binding as a means of reducing a woman’s mobility. Women often actively participate in these practices; whether a woman performing a genital modification on another woman or foot binding emerging as a fashion fueled among women, there is a recognition that these paternity-controlling traits help entice potential mates.

Because of the derived nature of human paternal care, with gorillas the closest to a Great Ape analogue (in that gorilla males seem concerned with paternity established in long-term reproductive bonds), humans appear to exhibit a greater concern over paternity certainty. The question for humans isn’t just how to mate with a reproductive viable female but additionally how to ensure that one’s paternal care is channeled to his biological offspring rather than those sired by another man. Accordingly, humans exhibit a concern with paternity certainty manifest in various ways. Like for other mammals, putative human fathers can employ phenotype matching and experience mating with a mother as cues to paternity. Some studies suggest that putative human fathers rely on visual cues of resemblance and mating experience with a mother to inform their paternity certainty (or uncertainty). Additionally, humans can employ gossip or even DNA-based paternity testing kits to hone in on paternity (Gray and Anderson 2010).

A review of 67 human paternity studies revealed that when males think they are the biological father, they typically are (1.7% false paternity estimate in 22 studies); when they think they might not be the father, they often aren’t (29.8% false paternity in 31 studies); and in more ambiguous studies, an intermediate rate of false paternity applies (16.7% in 14 studies) (Anderson 2006). While various surveys quantify rates and patterns of human extrapair sex, these paternity estimates suggest how often those incidents translate to false paternity. Additionally, various features of human reproductive anatomy and physiology indicate relatively low sperm competition pressures (or pressures for the sperm of different males to compete within a female’s reproductive tract), another line of evidence suggesting that female multi-male mating has been relatively rare across recent hominin evolutionary history (Dixson 2009).