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Are Humans Naturally Monogamous? | The Hook Up Podcast

The Hook Up Podcast tackles the perennial question, "Are humans naturally monogamous?" Host D. Selman and Pip Rasmusen frame the episode as a research‑driven deep dive, deliberately avoiding moral judgments about polyamory versus monogamy. They outline the scientific terrain, from evolutionary anthropology to neurobiology, to determine whether monogamy is a cultural construct or a biological imperative. The discussion presents two opposing bodies of evidence. Pro‑non‑monogamy scholars cite Christopher Ryan’s *Sex at Dawn*, arguing that hidden ovulation encouraged frequent sex as a social glue in small, cooperative bands. Evolutionary biologists like David P. Barash highlight classic polygyne benefits—male sperm competition, increased genetic diversity, and resource acquisition—while noting that over 80% of early societies were polygynous. Physiological clues, such as medium‑sized testes and straightforward human penile morphology, are interpreted as signs of reduced sperm competition. Conversely, researchers emphasizing innate monogamy point to oxytocin‑driven pair bonding, Helen Fisher’s brain‑imaging work, and Cat Bonahan’s analysis of primate reproductive anatomy, which suggests humans evolved for longer, more exclusive partnerships. A recent Cambridge study placed humans seventh on a monogamy scale among 35 species, with 66% full‑sibling rates—far higher than chimpanzees or dolphins. Evolutionary anthropologist Anna Matchen clarifies the critical distinction between social monogamy (co‑parenting) and true sexual monogamy, noting that only 0.0015% of species exhibit the latter. The episode underscores that human mating strategies are neither wholly monogamous nor entirely promiscuous but exist on a spectrum shaped by biology, ecology, and culture. Recognizing the nuance informs relationship counseling, public policy on marriage, and personal expectations, urging listeners to align their partnership models with both evolutionary insights and individual values.