Using monozygotic twin differences to examine the relationship between parental affection and personality: a life history account

Article history: Initial receipt 2 February 2017 25 September 2017 Final revision received 25 September 2017 Available online xxxx The relationship betweenmaternal and paternal affection, reported in adulthood, and personality was examined using a genetically sensitive research design comparing differences betweenmonozygotic twins. Using life history theory as a framework, itwas predicted that differences inmaternal andpaternal affectionwould be predictive of differences in personality such that the twin reporting greater maternal and paternal affection would also report a personality profile reflective of a slow life history strategy. Specifically, it was predicted that the twin that reported greater maternal and paternal affection would also score high on the meta-traits of plasticity, stability, and the general factor of personality (GFP). The results supported the hypotheses, with most variance accounted for by the GFP. Additional results suggest that differences in paternal affection exhibit a stronger effect and that stability and plasticity may provide unique information about the association between differences in parental affection and differences in personality. Attachment and parental investment theories offer possible explanations for the findings, although alternative explanations are also proffered. It may also be beneficial for future research using a monozygotic twin difference approach to utilize biometric measures of life history strategy. © 2017 Elsevier Inc. All rights reserved.