Pregnancy outcomes among evacuees of the Sinabung volcano, 2010-2018 (North Sumatra, Indonesia): A matched cohort study

OBJECTIVES

Exposure to natural disasters during pregnancy is associated with adverse birth outcomes and increased probability of female births. Nonetheless, relatively little work has been done on evacuations of women living in close vicinity to volcanic eruptions. We conducted a retrospective cohort study among women from villages near the Sinabung volcano in North Sumatra, Indonesia, which has been active since 2010.

METHODS

We compared an "exposed" sample of women (n = 97) who were pregnant when forced to evacuate their villages due to the volcanic eruptions and an "unexposed" sample of non-evacuees (n = 97) matched for age and year of child's birth. We collected anthropometric data (height and weight of each woman) and conducted structured interviews about pregnancy outcomes and evacuation-related stress.

RESULTS

Evacuation led to an almost five-fold increase in the adjusted odds of having an early or preterm birth in non-imputed (OR = 4.84, 95% CI: 1.31-17.92) and multiply imputed (OR = 4.84, 95% CI: 1.29-19.19) analyses. It also led to approximately a 1 cm decrease in birth length in the non-imputed (β = -1.10, 95% CI: -1.96-0.24) and multiply imputed (β = -1.17, 95% CI: -1.20-0.36) analyses, both including controls for confounders. We found decreasing birth length with increasing stress among evacuees. There was no discernible effect of evacuation or stress on the other outcomes.

CONCLUSIONS

Both adverse effects we documented can exert negative influences on later-in-life outcomes for children of women pregnant during evacuation. This should be considered when developing protocols for supporting women and connecting them with clinical resources when evacuated from natural disasters.

Exploring the Great Schism in the Social Sciences: Confirmation Bias and the Interpretation of Results Relating to Biological Influences on Human Behavior and Psychology

The nature-nurture debate is one that biologists often dismiss as a false dichotomy, as all phenotypic traits are the results of complex processes of gene and environment interactions. However, such dismissiveness belies the ongoing debate that is unmistakable throughout the biological and social sciences concerning the role of biological influences in the development of psychological and behavioral traits in humans. Many have proposed that this debate is due to ideologically driven biases in the interpretation of results. Those favoring biological approaches have been accused of a greater willingness to accept biological explanations so as to rationalize or justify the status quo of inequality. Those rejecting biological approaches have been accused of an unwillingness to accept biological explanations so as to attribute inequalities solely to social and institutional factors, ultimately allowing for the possibility of social equality. While it is important to continue to investigate this topic through further research and debate, another approach is to examine the degree to which the allegations of bias are indeed valid. To accomplish this, a convenience sample of individuals with relevant postgraduate degrees was recruited from Mechanical Turk and social media. Participants were asked to rate the inferential power of different research designs and of mock results that varied in the degree to which they supported different ideologies. Results were suggestive that researchers harbor sincere differences of opinion concerning the inferential value of relevant research. There was no suggestion that ideological confirmation biases drive these differences. However, challenges associated with recruiting a large enough sample of experts as well as identifying believable mock scenarios limit the study's inferential scope.

Evitação e proibição do incesto: fatores psicobiológicos e culturais

Resumo Embora historicamente a regulação proibitiva do incesto seja considerada um fenômeno cultural quase universal que não é influenciado por fatores psicobiológicos relativos à história evolutiva da espécie humana, evidências recentes têm questionado essa visão tradicional e defendido que a evitação e a proibição do incesto são influenciadas biológica e cognitivamente com a cultura. Este artigo objetiva desenvolver uma discussão teórica acerca da inibição e proibição do incesto, enfatizando os mecanismos evolutivos subjacentes a esses fenômenos. Argumenta-se a existência de mecanismos endógenos que evoluíram porque inibem a atividade sexual entre parentes próximos e que formam a base para regular socialmente a proibição do incesto (mecanismo exógeno). Destaca-se o efeito Westermarck, no qual a proximidade de pessoas que vivem juntas desde a infância provoca uma aversão ao intercurso sexual entre elas. A ausência de propensão ao incesto e sua proibição institucional constituem uma complexa integração entre fatores psicobiológicos e culturais.

The Westermarck Hypothesis and the Israeli Kibbutzim: Reconciling Contrasting Evidence

The case of the communal education system in the Israeli kibbutzim is often considered to provide conclusive support for Westermarck's (1891) assertion regarding the existence of evolutionary inbreeding avoidance mechanisms in humans. However, recent studies that have gone back to the kibbutzim seem to provide contrasting evidence and reopen the discussion regarding the case of the kibbutzim and inbreeding avoidance more generally (Lieberman & Lobel, 2012; Shor & Simchai, 2009). In this article, I reassess the case of the kibbutzim, reevaluating the findings and conclusions of these recent research endeavors. I argue that the differences between recent research reports largely result from conceptual and methodological differences and that, in fact, these studies provide insights that are more similar than first meets the eye. I also suggest that we must reexamine the common assumption that the kibbutzim serve as an ideal natural experiment for examining the sources of incest avoidance and the incest taboo. Finally, I discuss the implications of these studies to the longstanding debate over the Westermarck hypothesis and call for a synthetic theoretical framework that produces more precise predictions and more rigorous empirical research designs.