A Laboratory Simulation of Parental Investment Decisions: The Role of Future Reproductive Opportunities and Quality of Offspring in Determining Levels of Parental Investment

Abstract

Hagen's Defection Hypothesis (2002) predicts that a mother's age and the quality of her offspring are critical factors in determining her investment in her newborn. We tested this hypothesis using hamster races in which 113 college student participants received a hamster ("offspring") and 10 poker chips ("resources") to "invest" into the hamster based on information about the quality of the hamster and about the possibility of future races. Subjects invested the most in low quality offspring when they expected to run only one race and the least in low quality offspring when they expected more racing opportunities in the future. Offspring quality affected investment differently depending on the presence or absence of future investment opportunities and the sex of the subject. Overall, the results supported Hagen's model of parental investment and also suggest that parental investment may be explained by conscious as well as unconscious decision-making.

Profiles of Maternal Care Observed in a Group of Brazilian Mothers: an Exploratory Study

“…However, it seems that some variables have more influence than others. For example, age was a discriminating variable, corroborating the prediction made by Parental Investment theory and authors (Keller & Chasiotis, 2007;Kramer & Lancaster, 2010;Turner, 2006). We observed that as reproductive potential decreases, maternal investment increases, since mothers in P2 and P3 profiles invested more than younger mothers in P1, and PROFILES OF MATERNAL CARE less than older mothers in P4, at least in one of the measures (stimulation scores).…”

“…Mother's age is expected to affect fitness payoff of investment, as it is related to future reproductive prospects. As women get older future reproductive prospects decrease and, as a consequence, the value of current offspring (to mothers' fitness) rises, prompting the display of increased investment (Kramer & Lancaster, 2010;Turner, 2006). Ecological conditions, mainly represented by mothers' access to resources, are also expected to affect fitness payoff of investment.…”

“…We believe that the description of patterns or profiles of care can contribute to the literature on childrearing and may be relevant to the development of programs to promote health and development for women and children. Based on the literature, we took into consideration mothers' variables such as age (Keller & Chasiotis, 2007;Kramer & Lancaster, 2010;Turner, 2006), educational level and social class (as indications of socio-economical conditions) (Abels et al, 2005;Kaplan & Lancaster, 2003;Sparks, 2011;Yeung et al, 2002;Zortéa & Tokumaru, 2010), style of relationship (adult attachment) (Del Giudice & Belsky, 2011b), and relationship to the family of origin (Keller et al, 2006); and variables of the context, such as size of the city they live (Seid- de-Moura et al, 2008;Vieira et al, 2010); and reported social support (Keller & Chasiotis, 2007;Martins et al, 2009;Silva & Tokumaru, 2008). We contrasted these variables to the ones related to the type of care provided to their child (i.e.…”