Infant attachment security and the timing of puberty: testing an evolutionary hypothesis.
Life-history theories of the early programming of human reproductive strategy stipulate that early rearing experience, including that reflected in infant-parent attachment security, regulates psychological, behavioral, and reproductive development. We tested the hypothesis that infant attachment insecurity, compared with infant attachment security, at the age of 15 months predicts earlier pubertal maturation. Focusing on 373 White females enrolled in the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development, we gathered data from annual physical exams from the ages of 9½ years to 15½ years and from self-reported age of menarche. Results revealed that individuals who had been insecure infants initiated and completed pubertal development earlier and had an earlier age of menarche compared with individuals who had been secure infants, even after accounting for age of menarche in the infants' mothers. These results support a conditional-adaptational view of individual differences in attachment security and raise questions about the biological mechanisms responsible for the attachment effects we discerned.
Belsky
Jay
J
Institute for the Study of Children, Families and Social Issues, Birkbeck University of London, London, United Kingdom. j.belsky@bbk.ac.uk
Houts
Renate M
RM
Fearon
R M Pasco
RM
D000293:Adolescent; D000367:Age Factors; D005075:Biological Evolution; D002648:Child; D005260:Female; D006801:Humans; D007223:Infant; D016018:Least-Squares Analysis; D008423:Maternal Age; D008572:Menarche / Q000502:physiology* / Q000523:psychology; D008954:Models, Biological; D009034:Mother-Child Relations; D009769:Object Attachment