title: Lineage based differences in grandparental investment: evidence from a large British cohort study.
abstract: Evolutionary theory suggests that maternal grandparents will invest more in their grandchildren than paternal grandparents, due to the difference between the certainty of maternity and the uncertainty of paternity. Most tests of this prediction have tended to use retrospective ratings by grandchildren rather than examining grandparental behaviour. Using a large-scale data set from the UK (n>7000), significant differences are shown between maternal and paternal grandparents in terms of frequencies of contact with their newborn grandchildren, while controlling for a wide range of other variables. Maternal grandparents also provided a significantly wider range of financial benefits than paternal grandparents. Maternal grandparents were also more likely to provide essentials and gifts and extras for the baby. Multiple correspondence analysis showed that contact frequencies systematically related to other measures of grandparental investment, indicating that contact frequencies are a useful proxy measure to examine overall investment. Findings are discussed with reference to the paternity uncertainty hypothesis.
authors.affiliation: Centre for Behaviour and Evolution, Newcastle University, UK.
authors.forename: Thomas V
authors.initials: TV
authors.lastname: Pollet
authors.forename: Mark
authors.initials: M
authors.lastname: Nelissen
authors.forename: Daniel
authors.initials: D
authors.lastname: Nettle
mesh_terms: D000368:Aged; D002648:Child; D002668:Child Rearing; D015331:Cohort Studies; D005190:Family / Q000523:psychology*; D005260:Female; D006801:Humans; D016901:Intergenerational Relations; D008297:Male; D008875:Middle Aged; D006113:United Kingdom