title: Quality-quantity trade-off of human offspring under adverse environmental conditions.
abstract: A central paradigm in life-history theory is the trade-off between offspring number and quality. Several studies have investigated this trade-off in humans, but data are inconclusive, perhaps because prosperous socio-cultural factors mask the trade-off. Therefore, we studied 2461 offspring groups in an area under adverse conditions in northern Ghana with high fertility and mortality rates. In a linear mixed model controlling for differences in age and tribe of the mother and socioeconomic status, each additional child in the offspring group resulted in a 2.3% (95% CI 1.9-2.6%, P < 0.001) lower proportional survival of the offspring. Furthermore, we made use of the polygamous population structure and compared offspring of co-wives in 388 households, thus controlling for variation in resources between compounds. Here, offspring survival decreased 2.8% (95% CI 2.3-4.0%, P < 0.001) for each increase in offspring number. We interpret these data as an apparent quality-quantity trade-off in human offspring.
authors.affiliation: Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: J J
authors.initials: JJ
authors.lastname: Meij
authors.forename: D
authors.initials: D
authors.lastname: van Bodegom
authors.forename: J B
authors.initials: JB
authors.lastname: Ziem
authors.forename: J
authors.initials: J
authors.lastname: Amankwa
authors.forename: A M
authors.initials: AM
authors.lastname: Polderman
authors.forename: T B L
authors.initials: TB
authors.lastname: Kirkwood
authors.forename: A J M
authors.initials: AJ
authors.lastname: de Craen
authors.forename: B J
authors.initials: BJ
authors.lastname: Zwaan
authors.forename: R G J
authors.initials: RG
authors.lastname: Westendorp
mesh_terms: D000367:Age Factors; D001723:Birth Rate; D002648:Child; D046688:Child Mortality; D003710:Demography; D004777:Environment; D005869:Ghana; D006801:Humans; D007407:Interviews as Topic; D016014:Linear Models; D012044:Regression Analysis; D012959:Socioeconomic Factors