Are Humans Naturally Monogamous? Science Questions If Multiple Partners Are the Norm

Kathmandu — A provocative and timely debate has once again surfaced in the global discourse: Are humans biologically designed to form romantic and sexual bonds with only one partner? Or are polygamy, polyandry, and polyamorous relationships embedded in our evolutionary heritage?
A BBC CrowdScience report published on July 5, 2025, sheds light on this pressing question with scientific depth and emotional nuance. The evidence, drawn from evolutionary biology, anthropology, and modern relationship dynamics, challenges the widely accepted belief that humans are inherently monogamous.
Elina, a Romanian woman living in London, shares her personal journey through ethically non-monogamous relationships. She describes how engaging with multiple partners—based on mutual consent—has led her to experience deeper emotional freedom and more honest conversations than she did in traditional monogamous setups. Her story offers a real-life example of how non-traditional relationship models can nurture psychological and emotional well-being.
Dr. Kit Opie, an evolutionary biologist at the University of Bristol in the UK, emphasizes that our sexual behaviors closely resemble those of our primate ancestors—gorillas, chimpanzees, and bonobos—who often engage in multiple sexual partnerships. According to him, early humans also practiced diverse sexual behaviors, but environmental pressures and the need for cooperative child-rearing may have gradually led to the adoption of monogamy as a practical survival strategy.
But is monogamy a moral truth or just an evolutionary compromise? Sara Blumenthal, a neuroscience PhD student in the U.S., argues that chemicals in the human brain—such as oxytocin and dopamine—create a complex tug-of-war. While oxytocin encourages bonding and intimacy, dopamine fuels novelty and exploration. This neurological competition is why many people struggle to remain sexually exclusive even when emotionally committed.
This internal conflict manifests in our modern lives: the longing for deep, long-term companionship on one hand, and the natural pull toward sexual diversity on the other. Practices like polyandry—where one woman has multiple husbands—still exist in regions of the Himalayas, parts of Africa, and among Indigenous groups in the Americas. These practices show humanity's adaptive flexibility and how relationship structures evolve with social and environmental needs.
However, navigating multiple relationships is not without challenges. Those who engage in polyamory often face emotional strain, time constraints, jealousy, and societal stigma. Yet Elina insists that consensual non-monogamy fosters levels of honesty and emotional intimacy that traditional relationships often lack. “When there are no lies, you’re forced to talk about what really matters,” she says.
So the question lingers: If non-monogamy is a natural human trait, why do our societies overwhelmingly validate only monogamous relationships? Could future legal and moral frameworks embrace alternative relationship models like polyamory and polyandry? And are we already witnessing a slow redefinition of what love, commitment, and fidelity mean in the 21st century?
This isn’t just a philosophical or private matter—it touches the core of human identity, emotional freedom, and societal evolution. Where love exists, so too does complexity. And perhaps, now more than ever, the courage to embrace that complexity is becoming essential for personal authenticity and cultural progress.