The Fitness Effects of Men’s Family Investments

Abstract

Men's investments in parenting and long-term reproductive relationships are a hallmark feature of human reproduction and life history. The uniqueness of such male involvement among catarrhines has driven an extensive debate surrounding the selective pressures that led to and maintain such capacities in men. Three major pathways have been proposed through which men's involvement might confer fitness benefits: enhancing child well-being, increasing couple fertility, and decreasing likelihood of partner desertion. Previous research has explored the impact of father involvement on these factors individually, but here we present novel research that explores all three pathways within the same population, the Mayangna/Miskito horticulturalists of Nicaragua. Furthermore, we expand the traditional dichotomous measure of father presence/absence by using a continuous measure of overall male investment, as well as two continuous measures of its subcomponents: direct care and wealth. We find that men's investments are associated with children's growth and possibly with wife's marital satisfaction; however, they are not associated with couple fertility.

Dimensions of Fatherhood in a Congo Basin Village: A Multimethod Analysis of Intracultural Variation in Men’s Parenting and Its Relevance for Child Health

“…Attention to intracultural variation among fathers is relatively rare in studies of fatherhood in small-scale societies, which typically examine culture-level differences, compare fathers with mothers, or both (Fouts 2008;Hames 1992;Harkness and Super 1992;Morelli and Tronick 1992;Munroe 2002). Theoretical and empirical work has also focused on effects of father absence (Belsky, Steinberg, and Draper 1991;Lawson et al 2017;Sear and Mace 2008;Shenk et al 2013), but we know little about how variation between men, as present fathers and husbands, contributes to differences in child physical growth and health in small-scale societies (Winking and Koster 2015).…”

Caring for infants is associated with increased reproductive success for male mountain gorillas

“…First, they may selectively interact with their current offspring, thereby engaging in paternal care. Evidence for the paternal care hypothesis is now well-established in some of the Old World primate species in which relationships between males and infants are common 7 , 9 – 14 ). Alternatively, males may be investing in their future reproductive success, rather than their current offspring, if affiliating with infants improves their chances of siring infants’ mothers’ future offspring (i.e.…”

Family ties: the multilevel effects of households and kinship on the networks of individuals

“…The social organization is oriented around nuclear family households that often include other adult residents beyond the male and female household heads. For instance, it is common for young married couples to reside with the bride's parents for several years, generally until the couple has a second or third child [ 33 ]. Unmarried individuals are also common, including widows and widowers, bachelors, or divorcées, who collectively comprise about 30% of the population of residents over the age of 18.…”