The Dual Nature of Human Desire: Pair-Bonding and Novelty

Humans demonstrate two distinct romantic and sexual drives: a drive for a romantic bond and a drive for sexual novelty. Evolutionary biology suggests that individuals are predisposed to seek secure pair-bond relationships while also possessing an appetite for variety.

Genetic Predisposition to Infidelity

Research conducted in 2010 identified a potential genetic predisposition to infidelity. A study involving behavioral surveys and DNA collection from young adults found a correlation between variations in dopamine receptor genes and reported engagement in infidelity.

Specifically, individuals with the "long" version of the dopamine D4 receptor gene were 50% more likely to report having engaged in infidelity, often multiple times.

This gene variant has previously been associated with thrill-seeking and risk-taking behaviors, including alcohol abuse and gambling.

It is noted that genetics are one of many factors influencing behavior, and a genetic predisposition does not equate to destiny.

Evolutionary Adaptation and Range of Tendencies

Evolutionary theory suggests that a range of personalities and tendencies within a population can be adaptive. For instance, in some species, having individuals who take risks and others who play it safe can lead to greater reproductive success for the population as a whole.

This concept applies to human behavioral variations, where a predisposition to sensation-seeking and sexual novelty in a segment of the population may have offered an evolutionary advantage through increased or more diverse offspring.

Pair-Bonding and Novelty

While humans possess a drive for sexual novelty, they also inherited an adaptive motivation to form and protect committed pair-bonds. This drive is shared by many species, some of which exhibit "mate guarding" behaviors. Human pair-bonds are understood as a mechanism to manage uncertainty, fostering trust and reliability in partners.

Infidelity is defined as non-consensual and a betrayal of relationship expectations, threatening the trust and stability of a pair-bond.

However, the drive for novelty can be expressed in healthy ways. Some individuals may explore open relationships, while others integrate novelty into their existing bonds. Research on long-term passion in couples indicates that maintaining sexual satisfaction involves engaging in a range of intimate and novel behaviors, such as romantic getaways, date nights, discussing fantasies, trying new positions, or using sex toys together. These actions are viewed as demonstrating a commitment to intimacy, trust, vulnerability, and attachment, thereby advancing passion within the relationship.