Attachment and pairbonding

• Relative to other primates, humans are born immature — less fully developed.
• Human parents often pairbond, which increases paternal investment in childrearing.
• On average, pairbonded partners support each other emotionally and motivationally.
• The process of building a pairbond can begin upon a first meeting.
• Once a pairbond has formed, the partners often exert themselves to maintain it.

Relative to other primates, Homo sapiens are born immature. To survive, they require intensive provisioning and nurturance across many years. One evolved mechanism for fostering such caregiving is for parents to pairbond — to develop and sustain a deep emotional connection to each other — which bolsters fathers’ contributions to childrearing. Such paternal investment increases the likelihood that offspring survive long enough to reproduce. On average, once a pairbond has formed, partners typically provide each other with emotional and motivational support and, ultimately, promote each other's psychological and physical health. Furthermore, they tend to exert themselves to sustain the pairbonded relationship over time, including by engaging in biased cognitive processing to derogate alternative romantic partners.