Exploring the links between early life and young adulthood social experiences and men's later life psychobiology as fathers

Abstract

Early life cues of environmental harshness and unpredictability have been hypothesized to influence within-species variation in the timing of life history transitions and the dynamics of reproductive strategies, such as investments in mating and parenting. It is also believed that adolesence is an influential developmental period for male reproductive strategies, with those who achieve greater social and sexual success during that period maintaining faster life history strategies into adulthood. If correct, such early life and post-pubertal experiences could also help shape the psychobiological pathways that mediate reproductive strategies, including the well documented physiological shifts that occur when some men become parents. Drawing on a large sample of Filipino men (n=417), we evaluate whether men who experienced cues of harshness or unpredictability in childhood or have earlier ages at sexual debut have elevated testosterone (T) as fathers. We also test whether males who experienced a combination of early life experiences of harshness or unpredictability and had earlier ages of sexual debut during adolescence had the most elevated T as fathers. We found that fathers who experienced early life harshness and who engaged in sex at an earlier age had elevated waking T. Among men transitioning to fatherhood across the 4.5-year follow-up period of this study, those who experienced unpredictability and who engaged in sex at an earlier age showed attenuated declines in waking T between baseline and follow-up. Complementing these findings, we found that fathers who first engaged in sex at later ages had greater acute declines in T when they played with their toddlers. We suggest that these patterns could reflect programming effects of sociosexual experiences during the years following the marked biological transitions that accompany puberty, which occur along with the better-studied effects of earlier life exposures to stressors. Overall, our results support the hypothesis that early life circumstances and social and sexual experiences, from early life to young adulthood, help calibrate physiological axes as key mechanisms coordinating dynamic life history strategies.

Parental hormones are associated with crop loss and family sickness following catastrophic flooding in lowland Bolivia

“…Fathers provide critical investments, including food, protection, instruction and direct care. Comparing relative impacts of different types of paternal investments and measuring hormonal correlates of paternal investment is a growing area of research [9, 10, 12, 14]. Following a major 2014 flood, we find that greater crop losses are associated with lower levels of male testosterone, consistent with parallel literatures addressing physiology of the stress response and parenting.…”

“…Testosterone is associated with paternal investment in humans and other primates [8–12], and its relationship to family stress, including crop loss and family illness and injury, is of interest to the growing field of research examining the physiology of parenting. New methods of quantifying male physiological investment using hormonal activity have recently become possible, providing insight into individual-level variation in men’s responses to young children [8, 13, 14]. Relevant studies show that high-investing fathers have lower levels of testosterone than lower-investing fathers [10, 14].…”

“…New methods of quantifying male physiological investment using hormonal activity have recently become possible, providing insight into individual-level variation in men’s responses to young children [8, 13, 14]. Relevant studies show that high-investing fathers have lower levels of testosterone than lower-investing fathers [10, 14]. However, most of these studies focus on fatherhood during relatively stable environmental conditions, and thus little is known about the physiology of parenthood following a major environmental shock.…”

“…While researchers have not yet examined how long this decline in testosterone lasts following a sports loss, lower levels of testosterone are associated with depressive symptoms in cases of both acute and chronic depressive symptoms [48, 49]. While testosterone is associated with many aspects of male biology and psychology such as investment in offspring [8–10, 12, 14, 50], testosterone is not generally associated with maternal behavior in females where other hormones like oxytocin play an important role in mother-infant bonding [7]. In light of this evidence, we expect that men who experience greater destructive impacts of flooding (indicated by crop losses and threats to family health) will have lower levels of testosterone.…”

The postnatal testosterone rebound in first‐time fathers and the quality and quantity of paternal care

“…For example, Sarma et al. (2018) found that new fathers who experienced early life unpredictability showed attenuated declines in T across a 4.5‐year study period—perhaps evidence that maintaining elevated T is indicative of a more mating‐oriented (over parenting) strategy. Our own work (Corpuz & Bugental, 2020) demonstrated that the timing of a male’s sexual development predicted the magnitude of his postnatal T rebound.…”