Cacilda Jethá Books

The dominant theory of evolutionary psychology tells us that humans evolved for pair-bonding — the tidy narrative that two parents working together improved survival for their offspring, and that sexual fidelity was thus adaptive. This neat model underpins modern moral frameworks and has even been u...

From Sex at Dawn: How We Mate, Why We Stray, and What It Means for Modern Relationships

If we test the traditional model of monogamy against real cross-cultural and biological evidence, cracks appear immediately. Many anthropologists have documented societies where ‘pair bonding’ is only one expression of human sexuality among many, and where possessing exclusive sexual rights would be...

From Sex at Dawn: How We Mate, Why We Stray, and What It Means for Modern Relationships

For generations, evolutionary psychology has told a familiar story: humans evolved to form monogamous pairs. According to this account, males needed to ensure paternity to pass on their genes, while females required reliable providers to support their children. The union of two individuals was thus ...

From Sex at Dawn: The Prehistoric Origins of Modern Sexuality

Imagine a world where survival depended on mutual sharing, where food, security, and companionship circulated freely within a small tribe. This was the reality of prehistoric foragers. In such settings, sexual exclusivity would have been a poor strategy, cutting individuals off from the emotional we...

From Sex at Dawn: The Prehistoric Origins of Modern Sexuality