Did romantic love evolve by co-opting mother-infant bonding mechanisms?

by Mane Kara-Yakoubian
January 22, 2024
in Evolutionary Psychology, Relationships and Sexual Health, Social Psychology

A new theory suggests that romantic love evolved from mechanisms originally serving mother-infant bonding, challenging Fisher’s long-standing theory of independently evolved emotion systems that categorize sex drive, romantic attraction, and attachment as distinct systems. This theory article was published in Frontiers in Psychology.

Adam Bode proposes that the evolution of romantic love involved the co-opting of neurobiological and endocrinological systems integral to mother-infant bonding. The researcher presents several lines of evidence to support this theory.

To begin, there are significant similarities in the psychological aspects of mother-infant bonding and romantic love. Both involve intense emotional connections, a strong drive for physical closeness, and a deep focus on the loved one. This includes behaviors such as proximity-seeking, exclusive attention to the loved one, and a heightened sense of empathy and responsibility.

Further, studies have shown overlapping brain activity in the states of romantic love and mother-infant bonding. For example, regions rich in oxytocin and vasopressin receptors, which play crucial roles in emotional and social behaviors, are activated in both types of bonding. Notably, areas such as the ventral tegmental area and other parts of the brain’s reward circuitry are involved in both maternal and romantic love, suggesting shared pathways for bonding and attachment.

Hormonal patterns provide further evidence for this theory. Higher levels of oxytocin are found in individuals during the early stages of romantic relationships, similar to those in new mothers following childbirth. Oxytocin, given the nickname the “love hormone,” is known for its role in facilitating bonding and social recognition, both in parent-child and romantic relationships.

Behaviors observed in both mother-infant bonding and romantic relationships such as obsessive thinking, longing for emotional reciprocity, and mutually satisfying interaction patterns suggest common underlying mechanisms. For instance, the obsessive thoughts about an infant seen in new mothers parallel the preoccupation with a romantic partner in people experiencing romantic love.

The theory is further supported by similarities in the neuroendocrine responses in romantic love and mother-infant bonding. The interplay of neurotransmitters and hormones like dopamine, oxytocin, and possibly opioids in both states points to a shared neuroendocrine foundation that governs attachment and bonding behaviors.

Perhaps romantic love is an evolutionarily repurposed adaptation, deeply ingrained in human biology and fundamental to our social fabric. This theory presents a paradigm shift in understanding romantic love, proposing it as a complex evolutionary adaptation rooted in the fundamental mechanisms of human bonding.

Future research is encouraged to further explore and validate this theory, and to offer a more comprehensive understanding of the evolution of human bonding and relationships.

The paper, “Romantic love evolved by co-opting mother-infant bonding”, was authored by Adam Bode.