Parental investment and the optimization of human family size.


Lawson, DW; Mace, R; (2011) Parental investment and the optimization of human family size. Philosophical transactions of the Royal Society of London Series B, Biological sciences, 366 (1563). pp. 333-43. ISSN 0962-8436 DOI: https://doi.org/10.1098/rstb.2010.0297

Full text not available from this repository. (Request a copy)

Abstract

Human reproductive behaviour is marked by exceptional variation at the population and individual level. Human behavioural ecologists propose adaptive hypotheses to explain this variation as shifting phenotypic optima in relation to local socioecological niches. Here we review evidence that variation in fertility (offspring number), in both traditional and modern industrialized populations, represents optimization of the life-history trade-off between reproductive rate and parental investment. While a reliance on correlational methods suggests the true costs of sibling resource competition are often poorly estimated, a range of anthropological and demographic studies confirm that parents balance family size against offspring success. Evidence of optimization is less forthcoming. Declines in fertility associated with modernization are particularly difficult to reconcile with adaptive models, because fertility limitation fails to enhance offspring reproductive success. Yet, considering alternative measures, we show that modern low fertility confers many advantages on offspring, which are probably transmitted to future generations. Evidence from populations that have undergone or initiated demographic transition indicate that these rewards to fertility limitation fall selectively on relatively wealthy individuals. The adaptive significance of modern reproductive behaviour remains difficult to evaluate, but may be best understood in response to rising investment costs of rearing socially and economically competitive offspring.

Item Type: Article
Faculty and Department: Faculty of Epidemiology and Population Health > Dept of Population Health (2012- ) > Dept of Population Studies (1974-2012)
Faculty of Epidemiology and Population Health > Dept of Population Health (2012- )
PubMed ID: 21199838
Web of Science ID: 285793800003
URI: http://researchonline.lshtm.ac.uk/id/eprint/1865

Statistics


Download activity - last 12 months
Downloads since deposit
0Downloads
271Hits
Accesses by country - last 12 months
Accesses by referrer - last 12 months
Impact and interest
Additional statistics for this record are available via IRStats2

Actions (login required)

Edit Item Edit Item