Parental Responsibilities
Daughters Promote Pair-Bonding in Fathers in Modern Western Contexts
Krystal Duarte et al.
University of Pennsylvania Working Paper, March 2026
Abstract:
Prior research demonstrates a reliable association between low-quality father involvement or absence and negative outcomes for daughters, particularly in contemporary Western cultures. For example, low-quality father involvement and absence is associated with accelerated sexual development, promiscuity, and risk-taking. The current research tests the prediction that the presence of a daughter shifts male psychology to promote long-term romantic pair-bonding to signal to daughters that male investment is reliable. Using cross-sectional, longitudinal, and transition-to-parenthood data from parents with either a daughter or a son (N=1694), we found an association between daughters and fathers' long-term pair-bond motivation toward the biological mother. Longitudinal evidence suggested that this effect diminished with daughters' age, consistent with the father absence literature. Transition-to-parenthood data provided additional support that this pattern. Changes in male mating psychology occurred alongside daughters' births and was not related to individual differences between fathers of daughters and sons prior to parenthood. This effect could reflect an adaptation to signal reliability of male investment and prevent abandonment during girls' development.
Wide and Shallow: Digital Technology and the Post-2007 Fertility Decline
Nathan Hudson & Hernan Moscoso Boedo
University of Cincinnati Working Paper, May 2026
Abstract:
Fertility has fallen sharply across the high-income world since 2007. For the first time in human history, world fertility is close to the replacement rate. We propose a new mechanism that accounts for this decline: the digital revolution has fundamentally reshaped how humans interact with one another, favoring broad and shallow connections at the expense of the deeper ones that require sustained in-person investment. We formalize this through a dynamic household-production model in which relational capital affects partnership formation, divorce, and fertility. Calibrated to US 2007-2024 time-use and fertility data, the model accounts for the observed fertility decline; a counterfactual holding the relative price of phones at its 2007 level explains 43 percent of the change in fertility rates in the US. The same calibration matches the median OECD country's observed decline in total fertility rate. Two causal designs identify the mechanism: a terrain-ruggedness IV on county-level broadband and 4G LTE rollout for teen fertility, and a cohort-Bartik design on 4G LTE rollout for partnership formation among smartphone-era cohorts.
The Geography of Lifecycle Human Capital Accumulation
Ben Sprung-Keyser & Sonya Porter
NBER Working Paper, May 2026
Abstract:
We examine how place shapes the production of human capital across the lifecycle. We ask: do those places that most effectively produce human capital in childhood also have local labor markets that do so in adulthood? We consider the following determinants of wages across place: 1) location-specific wage premiums, 2) adult human capital accumulation due to local labor market exposure, and 3) childhood human capital accumulation. We construct estimates of location wage premiums using AKM-style estimates of movers across US commuting zones and validate these estimates using evidence from plausibly exogenous out-migration from New Orleans in response to Hurricane Katrina. Next, we examine differential earnings trajectories among movers to construct estimates of human capital accumulation due to labor market exposure. We validate these estimates using wage changes of multi-time movers. Finally, we estimate the impact of place on childhood human capital production using age variation in moves during childhood. Crucially, our estimates of location wage premiums and adult human capital accumulation allow us to construct estimates of the causal effect of place during childhood that are not confounded by correlated labor market exposure. Using these estimates, we show there is a tradeoff between those places that most effectively produce human capital in childhood and the local labor markets that do so in adulthood. We find that each 1-rank increase in earnings due to adult labor market exposure trades off with a 0.5 rank decrease in earnings due to the local childhood environment. This pattern is closely linked to city size, as adult human capital accumulation generally increases with city size, while childhood human capital accumulation falls. These divergent trajectories are associated with differences in both the physical structure of cities and the nature of social interaction therein.
The Rise of Zero Fertility Desire in China
Xiangning Xu
Brown University Working Paper, April 2026
Abstract:
Rising childlessness across low-fertility societies has commonly been interpreted as the result of unrealized fertility intentions rather than the rejection of parenthood itself. However, the emergence of zero fertility desire raises the possibility that declining fertility desire may play an increasingly important role alongside unmet fertility in shaping contemporary fertility outcomes. Using China as an empirical case, this paper examines zero fertility desire among individuals aged 18-24. Drawing on six waves of the China General Social Survey (2012-2023), the share reporting no desire for children increased from approximately 5% in 2012 to 32% in 2023, accompanied by a pronounced gender gap: by 2023, nearly half of young women reported zero fertility desire. Logistic regression results show gender to be the most consistent predictor, more so than education and hukou status. Among young women, urban-rural differences are not statistically significant, while college-educated women exhibit higher odds of reporting zero fertility desire than their non-college educated peers. These findings suggest that declining fertility desire may increasingly contribute to rising childlessness and highlight potential limits of pronatalist policies that primarily target constraints on fertility intentions.
Investing When Fewer Expect to Parent: Fertility Expectations and Financial Risk-Taking
Judith Bohnenkamp, Ville Rantala & Melina Murren Vosse
University of Miami Working Paper, April 2026
Abstract:
We examine how fertility expectations influence financial risk-taking using nationally representative data from three countries. Our results indicate that childless adults who do not expect children are 21-36% more likely to invest in stocks than those who expect children, controlling for personal characteristics. This effect persists also when medical infertility instruments expectations. We find no similar effects for other savings categories, nor differences in self-reported risk tolerance. Households expecting children report shorter financial planning horizons, which may explain their lower risk-taking. These results suggest declining fertility can increase young adults' stock market participation through childbearing expectations.
Do Human Fetuses Form Long-Lasting Chemosensory Memories? Longitudinal Follow-Up From Fetus to Young Child of Facial Responses to Flavor/Odor Stimuli
Nadja Reissland et al.
Developmental Psychobiology, May 2026
Abstract:
Prenatal flavor exposure is known to provide the foundation for later flavor or odor preferences in humans, yet the persistence of fetal flavor/odor memories into early childhood remains unclear. In previous studies, fetuses at 32- and 36 weeks gestation were shown to display discriminative facial reactions following a single-dose flavor stimulation (bitter kale vs. non-bitter carrot), and repeated exposure to these flavors from 36 weeks until birth was associated with responses to flavor-specific odors in the first postnatal month. The current longitudinal follow-up tested whether the prenatal exposure to two specific flavors results in flavor-specific odor reactions at 3 years of age. Children (n = 12) who had participated in the fetal and neonatal phases of the study were tested at 3 years of age using controlled olfactory presentations of the same flavors. Results showed that the 3-year-olds exhibited a significantly reduced rate of negative facial expressions in response to the odor they had been repeatedly exposed to in utero (p < 0.001), indicating continuity from prenatal sensory experience to early childhood behavioral responses. Thus, flavor exposure in late gestation can result in long-lasting flavor/odor memory, confirming that the prenatal chemosensory environment can shape behavioral tendencies years after birth.