The evolutionary novelty of childcare by and with strangers.

Alloparenting by and with genetically unrelated individuals is evolutionarily novel; thus, the Savanna-IQ Interaction Hypothesis predicts that more intelligent parents are more likely to resort to paid childcare by strangers. Analyses of individual data (National Child Development Study) in the United Kingdom (Study 1) and macrolevel data from the United States (Study 2) and economically developed Organization for Economic Cooperation and Development (OECD) nations (Study 3) confirmed the hypothesis. Net of education, earnings, sex, current marital status, and number of children, more intelligent British parents were more likely to resort to paid childcare at ages 33 and 42; net of female labor force participation rate, median household income, median cost of childcare, and mean education, U.S. states with higher average intelligence had higher proportions of children (ages 0-4) in paid childcare; and net of maternal employment, gross domestic product (GDP) per capita, cost of childcare, and female educational attainment, OECD nations with higher average intelligence had higher proportions of infants (ages 0-2) in paid childcare. The results were remarkably consistent; both across the 50 U.S. states and 45 economically developed OECD nations, a one IQ point increase in the average intelligence of the population was associated with a 1.8% increase in the proportion of children in paid childcare. Contrary to earlier findings, there was some suggestive evidence that the experience of paid daycare might harm the cognitive development of children. The studies point to the importance of evolutionary perspective in developmental psychology and child development.

When intelligence hurts and ignorance is bliss: Global pandemic as an evolutionarily novel threat to happiness.

INTRODUCTION: The savanna theory of happiness posits that it is not only the current consequences of a given situation that affect happiness but also its ancestral consequences, and that the effect of ancestral consequences on happiness is stronger among less intelligent individuals. But what about situations that did not exist in the ancestral environment and thus have no ancestral consequences? Global pandemic is one such situation that has no ancestral analog, and the theory predicts such evolutionarily novel threats to have a negative effect disproportionately on the life satisfaction of more intelligent individuals. METHODS: We analyzed prospectively longitudinal data from population samples from the National Child Development Study (Study 1) and the British Cohort Study (Study 2). RESULTS: Consistent with the theoretical prediction, while more intelligent individuals were generally more satisfied with their lives than less intelligent individuals were throughout adulthood (albeit not because they were more intelligent but because they earned more money, were more likely to be married, and healthier), more intelligent individuals were less satisfied with their lives during the COVID-19 global pandemic because they were more intelligent. CONCLUSION: Higher intelligence may have a downside in the modern world, by allowing life satisfaction to be more vulnerable from being better able to comprehend the severity of problems that did not exist in the ancestral world.

Sunshine on my shoulders makes me happy. . . especially if I'm less intelligent: how sunlight and intelligence affect happiness in modern society.

The savanna theory of happiness proposes that, due to evolutionary constraints on the human brain, situations and circumstances that would have increased our ancestors' happiness may still increase our happiness today, and those that would have decreased their happiness then may still decrease ours today. It further proposes that, because general intelligence evolved to solve evolutionarily novel problems, this tendency may be stronger among less intelligent individuals. Because humans are a diurnal species that cannot see in the dark, darkness always represented danger to our ancestors and may still decrease our happiness today. Consistent with this prediction, the analysis of the National Longitudinal Study of Adolescent to Adult Health (Add Health) data shows that exposure to sunlight was associated with happiness but the association was significantly weaker among more intelligent individuals.

Self-Assembly of Surfactin into Nanofibers with Hydrophilic Channels in Nonpolar Organic Media.

We investigated the self-assembly of surfactin (SFNa), a cyclic peptide amphiphile produced by Bacillus subtilis, in a nonpolar organic solvent, namely, cyclohexane (CHx). The CHx solution of SFNa formed a thermoreversible organogel. Transmission electron microscopy and small-angle X-ray scattering (SAXS) analyses showed that gelation of the CHx solution of SFNa was caused by physical cross-linking of SFNa nanofibers. Wide-angle X-ray diffraction and Fourier-transform infrared analyses showed that the SFNa nanofibers were formed by one-dimensional stacking of SFNa rings with a period of 0.48 nm corresponding to the length of inter-ring hydrogen bonds between amide groups. A combination of SAXS and small-angle neutron scattering investigations of CHx and deuterated CHx solutions of SFNa nanofibers containing H2O or D2O showed that the SFNa nanofibers had a hydrophilic interior and formed water channels by water incorporation in this region.

Does global warming contribute to the obesity epidemic?

Endotherms must expend more energy to digest colder food, so they acquire more calories by eating food at a higher temperature than eating the identical food cold. A recent study shows that ownership of a microwave is associated with a small increase in BMI and obesity. The same logic applies to other substances that endotherms introduce into their bodies, like air. An analysis of the National Longitudinal Study of Adolescent to Adult Health (Add Health) shows that, net of sex, age, race, education, earnings, neighborhood characteristics, and exercise activities, atmospheric temperature is associated with small but statistically significant increases in BMI, weight, overweight, and obesity. Atmospheric temperature is more strongly associated than most exercise activities, and as strongly associated as age and population density. An average American might reduce weight by 15.1 lbs, BMI by 2.52 (half the difference between normal weight and obesity), and the odds of obesity by 54% by moving from Phoenix, AZ, to Barrow, AK, or, less dramatically, 5.7 lbs in weight, .95 in BMI (a fifth of the difference between normal weight and obesity), and 25% in the odds of obesity by moving mere 150 miles north to Flagstaff, AZ. Global warming under the worst-case scenario might produce an increase of 2.2 lbs in weight, .37 in BMI, and 12% in odds of obesity from 1961 to 2081.

Father absence, sociosexual orientation, and same-sex sexuality in women and men.

A recent evolutionary theory of female sexual fluidity suggests that women may not have sexual orientations in the same sense that men do, and that women's apparent sexual orientation may instead be a byproduct of their sociosexual orientation. One developmental factor that has consistently been shown to influence sociosexual orientation is father absence in childhood. Consistent with the prediction of the theory, the analyses of the National Longitudinal Study of Adolescent to Adult Health (Add Health) data show that father absence significantly increases women's, but not men's, same-sex sexuality in adulthood, whether it is measured by self identity, sexual behaviour, or romantic attraction. Further consistent with the theory, the association between father absence and same-sex sexuality in women is entirely mediated by their sociosexual orientation.

Paternal Age is Negatively Associated with Religious Behavior in a Post-60s But Not a Pre-60s US Birth Cohort: Testing a Prediction from the Social Epistasis Amplification Model.

Participation in social behaviors that enhance group-level fitness may be influenced by mutations that affect patterns of social epistasis in human populations. Mutations that cause individuals to not participate in these behaviors may weaken the ability of members of a group to coordinate and regulate behavior, which may in turn negatively affect fitness. To investigate the possibility that de novo mutations degrade these adaptive social behaviors, we examine the effect of paternal age (as a well-established proxy for de novo mutation load) on one such social behavior, namely religious observance, since religiosity may be a group-level cultural adaptation facilitating enhanced social coordination. Using two large samples (Wisconsin Longitudinal Study and AddHealth), each of a different US birth cohort, paternal age was used to hierarchically predict respondent's level of church attendance after controlling for multiple covariates. The effect is absent in WLS (ß = .007, ns, N = 4560); however, it is present in AddHealth (ß = - .046, p < .05, N = 4873) increasing the adjusted model R2 by .005. The WLS respondents were (mostly) born in the 1930s, whereas the AddHealth respondents were (mostly) born in the 1970s. This may indicate that social-epistatic regulation of behavior has weakened historically in the USA, which might stem from and enhance the ability for de novo mutations to influence behavior among more recently born cohorts-paralleling the secular rise in the heritability of age at sexual debut after the sexual revolution.

Effect of H2 treatment in a mouse model of rheumatoid arthritis-associated interstitial lung disease.

Rheumatoid arthritis (RA)-associated interstitial lung disease (ILD), a primary cause of mortality in patients with RA, has limited treatment options. A previously established RA model in D1CC transgenic mice aberrantly expressed major histocompatibility complex class II genes in joints, developing collagen II-induced polyarthritis and anti-cyclic citrullinated peptide antibodies and interstitial pneumonitis, similar to those in humans. Molecular hydrogen (H2 ) is an efficient antioxidant that permeates cell membranes and alleviates the reactive oxygen species-induced injury implicated in RA pathogenesis. We used D1CC mice to analyse chronic lung fibrosis development and evaluate H2 treatment effects. We injected D1CC mice with type II collagen and supplied them with H2 -rich or control water until analysis. Increased serum surfactant protein D values and lung densities images were observed 10 months after injection. Inflammation was patchy within the perilymphatic stromal area, with increased 8-hydroxy-2'-deoxyguanosine-positive cell numbers and tumour necrosis factor-α, BAX, transforming growth factor-ß, interleukin-6 and soluble collagen levels in the lungs. Inflammatory and fibrotic changes developed diffusely within the perilymphatic stromal area, as observed in humans. H2 treatment decreased these effects in the lungs. Thus, this model is valuable for studying the effects of H2 treatment and chronic interstitial pneumonia pathophysiology in humans. H2 appears to protect against RA-ILD by alleviating oxidative stress.

An association between women's physical attractiveness and the length of their reproductive career in a prospectively longitudinal nationally representative sample.

OBJECTIVES: Why is physical attractiveness more important for women's mate value in long-term mating than in short-term mating? This article replicates Bovet et al.'s (Journal of Evolutionary Biology. 2018; 31:229-238) recent finding that physically attractive women have a later expected age of menopause. METHODS: I analyzed the prospectively longitudinal, nationally representative sample of women in the National Child Development Study, applying t-test and multiple regression analyses. RESULTS: Analyses showed that girls rated physically attractive at age 7 underwent menarche 3.12 months earlier than other girls, and they had 32% smaller odds of having undergone menopause before age 51. The results suggest that more physically attractive women have longer reproductive careers, explaining why physical attractiveness may be a more important determinant of women's mate value in long-term mating than in short-term mating. CONCLUSIONS: Women's physical attractiveness predicts the timing of menarche and menopause, thereby the length of their reproductive careers.

Why are there more same-sex than opposite-sex dizygotic twins?

STUDY QUESTION: Are there more same-sex (SS) than opposite-sex (OS) pairs among dizygotic twins? SUMMARY ANSWER: In violation of Weinberg's Differential Rule, there are significantly more SS than OS pairs among dizygotic twins in nationally representative samples both in the UK and the USA. WHAT IS KNOWN ALREADY: Since at least 1874, twin researchers have assumed that dizygotic twins were equally likely to be SS or OS (later formalized as Weinberg's Differential Rule). However, recent research on the sex-specific nature of breastmilk suggests that OS twins might be at a developmental disadvantage relative to SS twins. There may therefore be evolutionary selection for the tendency to have SS twins and against the tendency to have OS twins. STUDY DESIGN, SIZE, DURATION: We analyze two population samples (not subject to Lykken's rule of two-thirds): the National Child Development Study in the UK (n = 17 419) from 1958 to present, and the National Longitudinal Study of Adolescent Health in the USA (n = 20 745) from 1994 to present. PARTICIPANTS/MATERIALS, SETTING, METHODS: We performed a one-sample t-test of the proportion of SS dizygotic twins against the theoretical null value of 0.5022. MAIN RESULTS AND THE ROLE OF CHANCE: The proportion of SS pairs among dizygotic twins was 0.6043 (t(325) = 3.838, P = 0.00015) in the UK and 0.5739 (t(520) = 3.398, P = 0.00073) in the USA. LIMITATIONS, REASONS FOR CAUTION: Twin type (monozygotic versus dizygotic) was classified by the mother, not by DNA typing, although supplementary data suggest that misclassification was negligible and supplementary analysis shows that potential misclassifications do not change our main conclusions. WIDER IMPLICATIONS OF THE FINDINGS: Weinberg's Differential Rule may be incorrect in its assumption of independence of sexes within dizygotic pairs, and there may be evolutionary selection for SS, and against OS, dizygotic pairs. STUDY FUNDING/COMPETING INTERESTS: None.

WHY DO SOCIETIES WITH HIGHER AVERAGE COGNITIVE ABILITY HAVE LOWER INCOME INEQUALITY? THE ROLE OF REDISTRIBUTIVE POLICIES.

Past studies suggest that, across nations, the average cognitive ability of a population is negatively associated with income inequality; societies with higher average cognitive ability tend to have lower levels of income inequality. However, it is not clear why. This paper proposes that social transfers from the wealthy to the poor may be a major mechanism by which some societies achieve lower income inequality than others, because more intelligent individuals may be more likely to have a preference for such transfers. Publicly available societal-level data were analysed in a series of multiple regression models. The empirical results in this study replicate the earlier finding that societies with higher cognitive ability have lower levels of income inequality, but the association is entirely mediated by social transfers. Social transfers therefore appear to be the primary mechanism by which societies with higher levels of cognitive ability achieve lower income inequality.

Kruppel-like factor 4 regulates matrix metalloproteinase and aggrecanase gene expression in chondrocytes.

Kruppel-like factor 4 (KLF4) is a zinc finger transcription factor that plays crucial roles during the development and maintenance of multiple organs. We and others have previously shown that KLF4 is involved in bone modeling and remodeling but roles played by KLF4 during skeletogenesis are still not fully understood. Here, we show that KLF4 is expressed in the epiphyseal growth plate and articular chondrocytes. Most articular chondrocytes expressed KLF4 in embryos but it localized only in a subset of superficial zone cells in postnatal mice. When KLF4 was overexpressed in chondrocytes in vitro, it severely repressed chondrocytic gene expressions. Global gene expression profiling of KLF4-transduced chondrocytes revealed matrix degrading proteinases of the matrix metalloproteinase and disintegrin and metalloproteinase with thrombospondin-1 domain families within the group of upregulated genes. Proteinase induction by KLF4 was alleviated by Trichostatin A treatment suggesting the possible involvement of epigenetic mechanisms on proteinase induction by KLF4. These results indicate the possible involvement of KLF4 in physiological and pathological aspects during cartilage development and maintenance.

Same-sex twins are taller and heavier than opposite-sex twins (but only if breastfed): Possible evidence for sex bias in human breast milk.

Recent studies show that human and other mammalian breast milk may be tailored for the sex of the offspring. Such sex bias suggests that opposite-sex twins, who receive breast milk that cannot simultaneously be tailored for both sexes, may be at a disadvantage for growth compared with same-sex twins. An analysis of data from the National Longitudinal Study of Adolescent Health (Add Health) shows that, controlling for sex, age, birth weight, and zygosity, breastfed same-sex twins are, on average, about 1 inch taller and 12 pounds heavier than their opposite-sex counterparts through adolescence and early adulthood. In contrast, never-breastfed same-sex twins tend to be shorter and lighter than their opposite-sex counterparts. These results may be potential evidence for sex bias in human breast milk and its long-term effects.

A diagnostic marker for superficial urothelial bladder carcinoma: lack of nuclear ATBF1 (ZFHX3) by immunohistochemistry suggests malignant progression.

BACKGROUND: Pathological stage and grade have limited ability to predict the outcomes of superficial urothelial bladder carcinoma at initial transurethral resection (TUR). AT-motif binding factor 1 (ATBF1) is a tumor suppressive transcription factor that is normally localized to the nucleus but has been detected in the cytoplasm in several cancers. Here, we examined the diagnostic value of the intracellular localization of ATBF1 as a marker for the identification of high risk urothelial bladder carcinoma. METHODS: Seven anti-ATBF1 antibodies were generated to cover the entire ATBF1 sequence. Four human influenza hemagglutinin-derived amino acid sequence-tagged expression vectors with truncated ATBF1 cDNA were constructed to map the functional domains of nuclear localization signals (NLSs) with the consensus sequence KR[X10-12]K. A total of 117 samples from initial TUR of human bladder carcinomas were analyzed. None of the patients had received chemotherapy or radiotherapy before pathological evaluation. RESULTS: ATBF1 nuclear localization was regulated synergistically by three NLSs on ATBF1. The cytoplasmic fragments of ATBF1 lacked NLSs. Patients were divided into two groups according to positive nuclear staining of ATBF1, and significant differences in overall survival (P = 0.021) and intravesical recurrence-free survival (P = 0.013) were detected between ATBF1+ (n = 110) and ATBF1- (n = 7) cases. Multivariate analysis revealed that ATBF1 staining was an independent prognostic factor for intravesical recurrence-free survival after adjusting for cellular grading and pathological staging (P = 0.008). CONCLUSIONS: Cleavage of ATBF1 leads to the cytoplasmic localization of ATBF1 fragments and downregulates nuclear ATBF1. Alterations in the subcellular localization of ATBF1 due to fragmentation of the protein are related to the malignant character of urothelial carcinoma. Pathological evaluation using anti-ATBF1 antibodies enabled the identification of highly malignant cases that had been overlooked at initial TUR. Nuclear localization of ATBF1 indicates better prognosis of urothelial carcinoma.

Why People Are in a Generally Good Mood.

Evidence shows that people feel mild positive moods when no strong emotional events are occurring, a phenomenon known as positive mood offset. We offer an evolutionary explanation of this characteristic, showing that it improves fertility, fecundity, and health, and abets other characteristics that were critical to reproductive success. We review research showing that positive mood offset is virtually universal in the nations of the world, even among people who live in extremely difficult circumstances. Positive moods increase the likelihood of the types of adaptive behaviors that likely characterized our Paleolithic ancestors, such as creativity, planning, mating, and sociality. Because of the ubiquity and apparent advantages of positive moods, it is a reasonable hypothesis that humans were selected for positivity offset in our evolutionary past. We outline additional evidence that is needed to help confirm that positive mood offset is an evolutionary adaptation in humans and we explore the research questions that the hypothesis generates.

Intelligence and childlessness.

Demographers debate why people have children in advanced industrial societies where children are net economic costs. From an evolutionary perspective, however, the important question is why some individuals choose not to have children. Recent theoretical developments in evolutionary psychology suggest that more intelligent individuals may be more likely to prefer to remain childless than less intelligent individuals. Analyses of the National Child Development Study show that more intelligent men and women express preference to remain childless early in their reproductive careers, but only more intelligent women (not more intelligent men) are more likely to remain childless by the end of their reproductive careers. Controlling for education and earnings does not at all attenuate the association between childhood general intelligence and lifetime childlessness among women. One-standard-deviation increase in childhood general intelligence (15 IQ points) decreases women's odds of parenthood by 21-25%. Because women have a greater impact on the average intelligence of future generations, the dysgenic fertility among women is predicted to lead to a decline in the average intelligence of the population in advanced industrial nations.

Sex Differences in the Association Between Hypertension and Incident Atrial Fibrillation.

Background Limited evidence is available on sex differences about the association between hypertension and incident atrial fibrillation (AF). Methods and Results We used a nationwide health checkup and claims database to analyze 3 383 738 adults (median age, 43 (36-51) years, 57.4% men). We investigated the relationship between hypertension and incident AF in men and women using a Cox regression model. We used restricted cubic spline functions to identify the association of blood pressure (BP) as a continuous parameter with incident AF. We categorized the men and women into 4 groups according to the 2017 American College of Cardiology/American Heart Association BP guidelines. During a mean follow-up of 1199±950 days, 13 263 AF diagnoses were recorded. The incidence (95% CI) of AF was 15.8 (15.5-16.1) per 10 000 person-years in men and 6.1 (5.9-6.3) per 10 000 person-years in women. Compared with normal BP, elevated BP, stage 1 hypertension, and stage 2 hypertension were associated with an increased risk AF in both men and women. However, the hazard ratios were greater in women than in men, and the P value for interactions in the multivariable model was 0.0076. The models using restricted cubic spline showed that the risk of AF associated with elevated systolic BP increased steeply above an approximate threshold of systolic BP of 130 mm Hg in men and 100 mm Hg in women. Although our primary findings were consistent across subgroup analyses, this association was most significant in younger individuals. Conclusions Although the incidence of AF was higher in men, the association between hypertension and incident AF was more pronounced in women than in men, suggesting a potential sex difference in the relationship between hypertension and incident AF.

AT motif binding factor 1 (ATBF1) is highly phosphorylated in embryonic brain and protected from cleavage by calpain-1.

ATBF1 is a transcription factor that regulates genes responsible for repairing tissues and the protection of cells from oxidative stress. Therefore reduction of ATBF1 promotes susceptibility to varieties of human diseases including neurodegenerative diseases and malignant tumors. The instability of the protein was found to be an important background of diseases. Because ATBF1 is composed of a large 404-kDa protein, it can be easily targeted by proteinases. The protein instability should be a serious problem for the function in the cells and practically for our biochemical study of ATBF1. We have found that calpain-1 is a protease responsible for the degeneration of ATBF1. We observed distinct difference between embryo and adult brain derived ATBF1 regarding the sensitivity to calpain-1. The comparative study showed that eight phosphorylated serine residues (Ser1600, Ser2634, Ser2795, Ser2804, Ser2900, Ser3431, Ser3613, Ser3697) in embryonic brain, but only one site (Ser2634) in adult brain. As long as these amino acids were phosphorylated, ATBF1 derived from embryonic mouse brain showed resistance to cleavage; however, treatment with calf intestine alkaline phosphatase sensitized ATBF1 to be digested by calpain-1. An inhibitor (FK506) against calcineurin, which is a serine/threonine specific phosphatase enhanced the resistance of ATBF1 against the digestion by calpain-1. Taken together, these results demonstrate that these phosphorylation sites on ATBF1 function as a defensive shield to calpain-1.

Intelligence and homosexuality.

The origin of preferences and values is an unresolved theoretical problem in behavioural sciences. The Savanna-IQ Interaction Hypothesis, derived from the Savanna Principle and a theory of the evolution of general intelligence, suggests that more intelligent individuals are more likely to acquire and espouse evolutionarily novel preferences and values than less intelligent individuals, but general intelligence has no effect on the acquisition and espousal of evolutionarily familiar preferences and values. Ethnographies of traditional societies suggest that exclusively homosexual behaviour was probably rare in the ancestral environment, so the Hypothesis would predict that more intelligent individuals are more likely to identify themselves as homosexual and engage in homosexual behaviour. Analyses of three large, nationally representative samples (two of which are prospectively longitudinal) from two different nations confirm the prediction.