Selection Hypothesis Research Articles

Амальтей Аттика: попытка реконструкции

The article is devoted to the problem of Amaltheum, known by Cicero’s mention at thecorrespondence and De legibus. N. V. Bugaeva doesn’t deny existence of such a component of Arpinum, but deals only with Atticus’ Amaltheum. There is a wide-spread opinion that Cicero’s friend created the memorial complex in Buthrotum, embodying the “ideal Rome”. Its characteristic feature was the chain of great Romans busts accompanied by short poetic inscriptions. But the evidence of Cornelius Nepos is not complete and concerns the later period of Atticus’s life; it is connected with Amaltheum very indirectly and the hypothesis of prominent compatriots lineal selection is under discussion. The most fruitful part of G. Sauron’s conceptionis the idea of safe refuge. Though the image of Zeus’ nurse or her attribute (grotto?) was the characteristic feature of Amaltheum, there is no evidence of the path fringed with great men sculptures or busts. According to N. V. Bugaeva, Amaltheum was the platane trees grove close to river without any structures (like pavilions).

Imperfect and Compound Microsatellites in the Genomes of Burkholderia pseudomallei Strains

Evolution of microsatellites (or simple sequence repeats, SSRs) is a complex process that converts perfect repeats to novel structural elements with functions poorly understood, such as imperfect and compound microsatellites. An in silico analysis often Burkholderia pseudomallei genomes revealed 215683 micro-satellites, and more than 98% of them proved imperfect. The density of microsatellites in the genome ranged from 2922.7 to 3022.6 per Mbp. Approximately 10.20-10.67% of the repeats were parts of compound micro-satellites. The of compound microsatellite density varied from 144.7 to 150.6 per Mbp. Between-strain differences in microsatellite distribution were explained by a direct correlation of the SSR density with the GC content and an inverse relationship between the SSR density and the genome size. For each B. pseudomallei chromosome, the SSR density similarly correlated with its size and GC content. Chromosome 2 showed a significant correlation between the SSR and compound microsatellite densities (r = 0.93, p < 10^(-3)). The association of imperfect and compound microsatellite densities with the structural features of each chromosome and the fact that motifs are degenerate and occur in few copies in the majority of B. pseudomallei microsatellites agree with the previous hypothesis of negative selection affecting extended SSRs. The mechanism of selection possibly involves an accumulation of point mutations, which lead to an interruption of the repeat during replication because easily passable secondary structures may form to stabilize the microsatellite length.

Differences in mutational processes and intratumour heterogeneity between organs: the local selective filter hypothesis.

Differences in mutational processes and intratumour heterogeneity between organs: the local selective filter hypothesis.

Differences in mutational processes and intra-tumour heterogeneity between organs: The local selective filter hypothesis.

Extensive diversity (genetic, cytogenetic, epigenetic and phenotypic) exists within and between tumours, but reasons behind these variations, as well as their consistent hierarchical pattern between organs, are poorly understood at the moment. We argue that these phenomena are, at least partially, explainable by the evolutionary ecology of organs’ theory, in the same way that environmental adversity shapes mutation rates and level of polymorphism in organisms. Organs in organisms can be considered as specialized ecosystems that are, for ecological and evolutionary reasons, more or less efficient at suppressing tumours. When a malignancy does arise in an organ applying strong selection pressure on tumours, its constituent cells are expected to display a large range of possible surviving strategies, from hyper mutator phenotypes relying on bet-hedging to persist (high mutation rates and high diversity), to few poorly variable variants that become invisible to natural defences. In contrast, when tumour suppression is weaker, selective pressure favouring extreme surviving strategies is relaxed, and tumours are moderately variable as a result. We provide a comprehensive overview of this hypothesis.Lay summary: Different levels of mutations and intra-tumour heterogeneity have been observed between cancer types and organs. Anti-cancer defences are unequal between our organs. We propose that mostly aggressive neoplasms (i.e. higher mutational and ITH levels), succeed in emerging and developing in organs with strong defences.

Market Selection in Large Economies: A Matter of Luck

Within a general equilibrium model with a continuum of traders, we investigate the Market Selection Hypothesis (MSH) - markets select traders with more accurate beliefs. We find, contrary to known results for economies with (only) finitely many traders, that risk attitudes affect survival and that markets might select against traders with accurate beliefs. Remarkably, even in these cases, asymptotic equilibrium prices reflect accurate beliefs. Thus, unlike known violations of MSH, we corroborate Freedman’s conjecture that market selection forces induce rational expectations.

Market selection in large economies: A matter of luck

In a general equilibrium model with a continuum of traders and bounded aggregate endowment, I investigate the market selection hypothesis that markets favor traders with accurate beliefs. Contrary to known results for economies with (only) finitely many traders, I find that risk attitudes affect traders' survival and that markets can favor “lucky” traders with incorrect beliefs over “skilled” traders with accurate beliefs. My model allows for a clear distinction between luck and skills, and it shows that market selection forces induce efficient prices even when accurate traders do not survive in the long run.

Non-Performing Loans of Commercial Banks in South Asian Countries: Adverse Selection and Moral Hazard Issues

In the South Asian region, a major cause of an increase in non-performing loans (NPL) is the bank’s adverse selection of borrowers. Using the GMM estimator, we empirically studied the bank-specific, industry specific and macroeconomic specific determinants of non-performing loans of banks in South Asian countries (Bangladesh, India, Nepal and Pakistan) from 1997 to 2012 and found that the adverse selection hypothesis of Stiglitz and Weiss (1981) was still effective. We found evidence for the bad luck, bad management, skimping and moral hazard hypotheses of Berger and DeYoung (1997) and their effect on the credit risk determination but we contributed to the literature by showing that ‘moral hazard type II’ (moral hazard between the bank management and the depositors) significantly affected the increase of non-performing loans. Bank size, industry concentration, inflation and GDP growth rate all significantly affected the sample countries’ non-performing loans. Empirical results showed a moderate degree of persistence of NPL and a late-hit of the global financial crisis in the region’s banking sector.

College as equalizer? Testing the selectivity hypothesis

Stratification research shows that occupational origins and destinations are weakly associated among individuals holding a college degree. The finding is taken to support the hypothesis that college equalizes opportunities and promotes social mobility. I test the competing hypothesis that the high level of social mobility reported for college degree holders results from the selectivity of this group. To control for selectivity, I reweigh a sample of college degree holders by the inverse probability of being a college degree holder conditional on observable characteristics of students before they enter college, including characteristics such as cognitive ability, personality traits, and beliefs about the future. Analyzing data from the National Longitudinal Survey of Youth 1979, I find no support for the selectivity hypothesis. These findings align with evidence based on indirect tests of the hypothesis, and indicate that college indeed appears to be an equalizer.

Sexual dimorphism of craniological characters in the European badger, Meles meles, (Carnivora, Mustelidae) from the Western Carpathians

In the Carpathian population of the European badger, existing studies show a considerable discrepancy in the level of sexual dimorphism. The main goal of the study was to assess the sexual size dimorphism of the Carpathian Meles meles population in the light of the main hypotheses explaining this phenomenon. We measured 22 craniometric characteristics on sexed skulls of adult specimens from the Western Carpathians and assessed the morphological differences between males and females. A multi-model approach combined with predictive modelling was used to identify craniological parameters that discriminate badger sexes. The sexual size dimorphism was manifested mainly in differences of the feeding apparatus. The inner (IMW) and outer width of mandible (OMW) showed the highest power to discriminate between males and females (classification accuracy > 80 %). The IMW and OMW of 30 and 69 mm, respectively, may be used as rough threshold values for determination of the badger sex in the Western Carpathians. Our results seem to be in accordance with the hypothesis of sexual selection. We suppose that more even distribution of small families or individuals in the mainland Europe implicates higher level of mating competition which leads to favouring bigger and stronger males. We suppose also some role of a predatory selection by large carnivores and competition with other burrowing species leading to a potentially higher survival chance of bigger individuals in the Carpathians.

Gender differences and managerial earnings forecast bias: Are female executives less overconfident than male executives?

This study examines whether firms with female executives forecast company earnings more conservatively. Consistent with the selectivity hypothesis, the results reveal firms with female CEOs tend to make conservative earnings forecasts in a perceived positive situation and firms with a higher percentage of female directors on the board are more likely to forecast earnings conservatively in a perceived negative situation. The conservativeness of female executives is not caused by lower management ability. This conservative behavior is not caused by personal factors such as military status, level of education, or area of study.

DNA Repair Genes May Influence Cognitive Outcomes in Adult Patients with Hematologic Malignancies (HM) Treated with Blood or Marrow Transplantation (BMT)

Introduction: We recently demonstrated that cognitive impairment (CI) is prevalent and persistent in HM patients treated with BMT (Sharafeldin et al., J Clin Oncol, 2018). While the impact of genetic factors on cognition in the non-oncology realm is well-recognized, limited information exists in HM patients treated with BMT. We tested the hypothesis that genetic variants in blood-brain barrier (BBB), drug transporter, telomere homeostasis, neurotransmission, neural repair and DNA repair are associated with CI in HM patients treated with BMT. We previously presented preliminary results of the Discovery cohort (Sharafeldin et al., Blood, 2016); here we present additional analyses (at the gene level) on the Discovery cohort, and replication of salient findings in an independent Validation cohort.Methods: The Discovery cohort consisted of prospective, longitudinally-assessed patients undergoing autologous or allogeneic BMT for HM at a single center. Cognitive function was assessed objectively using a battery of standardized tests prior to BMT, and at 6mo, 1y, 2y, and 3y post-BMT; germline DNA was collected pre-BMT. Global Deficit Score (GDS) was used as an indicator of CI (GDS ≥0.5 indicated CI). We employed a candidate gene approach, relying on biologically-plausible hypotheses for gene selection. Standard quality control procedures yielded 985 SNPs in 68 genes with a total genotyping call rate of 99% in 277 BMT recipients. Generalized estimating equation models were fitted to examine association of individual SNPs with CI. Linkage disequilibrium-based pruning yielded 326 independent tests, with an overall p-value threshold of 1.53x10-4 using Bonferroni correction for multiple testing. We also conducted gene-level analysis considering each gene as a SNP-set using the machine learning approach of logic regression, with cross-validation, to identify SNP-SNP interactions at the gene-level (Bonferroni p ≤ 7.94x10-4). An independent Validation case-control set from the BMT Survivor Study was used to replicate significant findings from the Discovery cohort, using conditional logistic regression models. Cases (n=141) were BMT survivors who reported: i) presence of memory/learning problems; and ii) severity of memory/learning problems. Controls (n=258) were BMT survivors without cognitive problems, matched (1-2/case) on race/ethnicity, HM, and time from BMT.Results:Discovery: Among the 277 patients in the Discovery cohort, mean age at BMT was 50y, 59% were males, 69% were non-Hispanic whites and 47% received an allogeneic BMT. Male sex (OR=3.2, 95%CI, 1.5-6.7, p=0.002) and lower pre-BMT cognitive reserve (OR=4.6, 95%CI, 2.2-9.6, p <0.0001) were associated with CI. Risk of CI was increased in the younger patients (<50y) if they received TBI (age*TBI interaction OR=3.86, 95%CI, 1.0-15.1, p=0.05). Final genetic models were adjusted for relevant variables with significant independent main effects including BMT type, age at BMT, sex, race/ethnicity, and cognitive reserve. We identified significant associations between CI and BBB, telomere homeostasis and DNA repair SNPs using the single-SNP (Fig 1) and gene-level analyses. Replication: The mean age at BMT was 44y, 54% were males, 88% were non-Hispanic whites and 5% received an allogeneic BMT. Replication models were adjusted for age at BMT, sex, race, and education and income levels. Of the 69 SNPs identified for replication, DNA repair SNPs from the single-SNP analysis rs13006837 on XRCC5 (OR=5.8, 95%CI, 2.7-12.3, p=2.0 x 10-5) and rs293796 on OGG1 gene (OR=11.4, 95%CI, 4.6-28.5, p-value=1.08 x 10-6) were successfully replicated. Five SNPs on DNA repair genes from the gene-level analysis showed individual statistically-significant associations in the Validation cohort: rs238417 on ERCC2 (OR=0.48, 95%CI, 0.25-0.91, p=0.03); rs2526698 on EXO1 (OR=0.57, 95%CI: 0.33-0.98, p=0·04); rs3793906 on MGMT (OR=1.96, 95%CI: 1.2-3.3, p=0.01); rs4725016 on RPA3 (OR=0.20, 95%CI, 0.05-0.92, p=0.04); and rs1479569 on XRCC4 (OR=2.3, 95%CI, 1.3-4.1, p=0.005).Conclusion: Our study provides genetic characterization of adult HM patients at increased risk of cognitive impairment following BMT; associations with DNA repair variants were independently replicated. These findings could have implications towards the personalized management of patients undergoing BMT. DisclosuresForman:Mustang Therapeutics: Other: Licensing Agreement, Patents & Royalties, Research Funding.

The effect of sexual selection on phenotypic diversification among human populations: A simulation study

Despite the generally low level of inter-population genetic differentiation in humans as compared with great apes, it has long been acknowledged that there is a considerable amount of geographic variations in human phenotypes, for example, skin pigmentation, cranial morphology, and soft-tissue facial morphology, to name but a few. Indeed, recent studies have suggested that the extent of inter-population diversity in some human phenotypes is greater than expected from random drift alone. Such an excess of phenotypic diversity is often attributed to adaptation to local environment. However, this account is valid only if populations differ in some ecological aspects that elicit differential selection acting on a given phenotypic feature. Another long-standing hypothesis is the sexual selection hypothesis, which claims that phenotypic diversity arises and/or is maintained owing to variations in preference for mating partners. In this paper, we explore the plausibility of the sexual selection hypothesis by means of computer simulations, in which the inter-population diversity of a quantitative trait is evaluated against the expectation from random drift, using the QST-FST comparison. As possible driving factors of sexual selection, we consider two types of mate-choice preference: preference for the population average and preference for a culturally-transmitted arbitrary trend. Our simulations suggest that sexual selection can, under certain circumstances, maintain and/or generate a detectable amount of inter-population phenotypic diversity, even when populations are ecologically identical and loosely connected to each other by mutual migration. Since mating decisions in humans are considerably affected by social learning, human mate-choice preference may be more readily diversified between populations than in other animals. We suggest, therefore, that some of the observed human phenotypic variations may be better understood as a product of cultural, rather than ecological, diversification.

Pharmacoinformatic Approaches to Design Novel Inhibitors of Protein Kinase B Pathways in Cancer.

Protein kinase B (PKB/Akt) belongs to the AGC superfamily of related serine/ threonine kinases with three structurally homologous mammalian isoforms, Akt1 (PKBα), Akt2 (PKBβ), and Akt3 (PKBγ). Besides sharing a similar structural topology, the difference in their physiological functions and tissue distribution makes Akt a cardinal node in diverse signaling pathways involving cell growth, survival, and proliferation. Various immunohistochemical studies have reported that the constitutive hyperactivation of Akt signaling is responsible for several types of human cancer, poor prognosis, as well as chemotherapeutic and radiotherapeutic resistance. Thus, inhibition of Akt activation represents a promising concept to induce cell apoptosis in various cancers and evade chemotherapeutic resistance. However, development of potent and selective inhibitors of Akt kinases as suitable antagonists remained gloomy and thus, only handful of compounds were selected for the clinical investigation but none of them could reach the market for routine clinical usage to circumvent cell proliferation and resistance to chemotherapeutic agents in cancer. Recent reports on achieving isoform selectivity by designing inhibitors against PH domain of Akt, together with availability of crystal structures of the PH domain of Akt1, open the possibility of structurebased design. In this article, various biological regulatory networks by which Akt and its substrates regulate cell growth and survival and several SAR and QSAR strategies in combination with molecular docking studies on selective inhibitors of Akt subtypes have been highlighted to further probe the selectivity of ligand-Akt subtypes interactions. Structure-based drug design studies revealed that the interactions of structurally diverse compounds with Glu121, Ala123, Asn171, Asp184, Glu228 and Ala230 amino acid residues in CAT domain and Arg23, Arg25, Lys30, Asn54 and Arg86 amino acid residues within PH domain play an important role in attaining significant inhibitory potency. Isoform selective inhibition of Akt might have clinical significance and thus, should be taken into account in future investigations. Moreover, an up to date isoform selective chemical data is required to further validate already reported isoform selective binding hypothesis.

Males and females evolve riskier traits in populations with eavesdropping parasitoids

Predation and/or parasitism often limits the evolution of conspicuous male traits and female preferences because conspicuous traits can attract predators or parasites and it is costly for females to associate with males that attract predators or parasites. As a result, males and females in high-risk populations are expected to evolve safer mating behaviors compared to individuals from low-risk populations. We tested this antagonistic selection hypothesis in the field cricket Gryllus lineaticeps. Males produce chirped songs, and both female crickets and the eavesdropping parasitoid fly Ormia ochracea prefer faster chirp rates. The flies attack the field crickets late in the breeding season and parasitized crickets die. We used a common garden rearing design to test for evolved differences in songs and preferences between high- and low-risk populations. In contrast to predictions of the antagonistic selection hypothesis, males from high-risk populations produced faster (riskier) chirp rates and females preferred faster chirps. We suggest that late-season parasitism selects for increased investment in reproductive traits to maximize reproduction before the advent of parasitoid activity (“late-season parasitism hypothesis”), which would at least explain riskier female preferences and potentially riskier male songs in the high-risk populations. Predation and parasitism may thus have diverse and unexpected effects on the evolution of reproductive behavior, depending upon the temporal pattern of predator- or parasite-induced mortality. Mating signals are typically conspicuous and not only attract partners but also predators and parasites. Even the silent mating partner may experience predation or parasitism by associating with the signaler. Under these circumstances, it is commonly assumed that natural and sexual selection act in opposite directions, effectively limiting the evolution of conspicuous signals and preferences. We demonstrate that an eavesdropping parasitic fly caused the evolution of preferences, and potentially songs, in a field cricket in the opposite, more conspicuous, direction than predicted by antagonistic selection. We argue that the temporal pattern of parasitism in relation to the reproductive season likely causes this unexpected evolutionary pattern. We propose the late-season parasitism hypothesis as an alternative to the antagonistic selection hypothesis, which might better explain more conspicuous mating trait values in other species that experience seasonal predation or parasitism.

Countering infanticide: Chimpanzee mothers are sensitive to the relative risks posed by males on differing rank trajectories.

Infanticide by males is common in mammals. According to the sexual selection hypothesis, the risk is inversely related to infant age because the older the infant, the less infanticide can shorten lactational amenorrhea; risk is also predicted to increase when an infanticidal male's chance of siring the replacement infant is high. Infanticide occurs in chimpanzees (Pan troglodytes), a species in which male dominance rank predicts paternity skew. Infanticidal male chimpanzees (if low-ranking) are unlikely to kill their own offspring, whereas those who are currently rising in rank, particularly when this rise is dramatic, have an increased likelihood of fathering potential future infants relative to any existing ones. Given that mothers should behave in ways that reduce infanticide risk, we predicted that female chimpanzees, and specifically those with younger, more vulnerable infants, would attempt to adjust the exposure of their infants to potentially infanticidal males. Specifically, mothers of young infants should reduce their association with adult males in general, and to a greater extent, with both low-ranking males and those rising in rank from a position where paternity of current infants was unlikely, to a rank where the probability of siring the next infant is significantly higher. We also investigated the alternative possibility that rather than avoiding all adult males, mothers would increase association with males of stable high rank on the basis that such males could offer protection against infanticide. We examined data on female association patterns collected from the Budongo Forest, Uganda, during a period encompassing both relative stability in the male hierarchy and a period of instability with a mid-ranking male rising rapidly in rank. Using linear mixed models, we found that mothers reduced their association with the rank-rising male, contingent on infant age, during the period of instability. We also found evidence that females preferentially associated with a potential protector male during the high-risk period. Our results support the sexually selected hypothesis for infanticide and demonstrate that female chimpanzees are sensitive to the relative risks posed by adult males.

Migration and depression: A cross-national comparison of Mexicans in sending communities and Durham, NC

RationaleLatino immigrants have been shown to average better health and longevity than native whites, in spite of their relative socioeconomic disadvantage. However, mental health outcomes stand in stark contrast to this epidemiological “paradox,” as factors such as depression are significantly higher for Latino immigrants than other groups. ObjectiveWe explore the link between migration and depressive feelings using a binational random survey of Mexicans in Durham, NC and sending communities in Mexico. MethodExplanations for the link between migration and depression, such as acculturative stress, lack of social support, and powerlessness and isolation, are analyzed by comparing results for protective vs. risk factors between residents of Mexico and Durham, and among immigrants themselves. Besides, selection hypothesis is explored using propensity matching scores. ResultsResults show little support for selection as an important source of migrant depression, and instead provide strong evidence that migration itself, and the disruption of social networks that it entails, is primarily responsible for the association. Family separation, in particular, is the strongest predictor of depressive feelings and accounts for a sizeable portion of the heightened depression among migrants. ConclusionsUnderstanding the subjective experiences of migration is necessary to better integrate newcomers into host societies.

Influence of haemosporidian infection status on structural and carotenoid‐based colouration in the blue titCyanistes caeruleus

Hypotheses postulating parasite‐mediated mate choice intrinsically assume that parasitic infections deteriorate the quality of male ornamentation. Although this assumption has often been studied in the context of carotenoid‐based colouration, only few studies investigated this with reference to structural feather colouration, which in many species plays a vital role in sexual selection. Here, using a three‐years dataset from a wild blue titCyanistes caeruleuspopulation, we examined the relationship between the haemosporidian infection status and the structural as well as the carotenoid‐based colouration of adult birds. Furthermore, we investigated potential differences in the impact on feather colouration between two examined parasite genera:PlasmodiumandHaemoproteus. For analysis of the feathers spectral reflectance we used both the tristimulus model and the avian tetrahedral colour space model, incorporating visual phenotype of the blue tit. Contrary to expectations we found that infected birds showed higher brightness, in both the structural and the carotenoid‐based colours. We also found no differences in the feather colouration between birds infected withPlasmodiumandHaemoproteus. Observed pattern might be best explained by the parasite‐mediated selection hypothesis, as only individuals of superior quality should be able to survive the acute stage of infection and therefore they could produce more elaborate ornamental colouration.

Can religion kill? The association between membership of the Apostolic faith and child mortality in Zimbabwe.

Existing literature has been equivocal about the effect of religion on utilization of health service and health outcomes. While followers of particularized theology hypothesis believe that doctrinal teachings, beliefs and values of religious groups directly influence health access and outcomes, the advocates of the selectivity hypothesis claim that the observed disparities between religious groups mainly reflect differential access to social and human capital which in turn determines health access and outcome rather than religion per se. Using household data from the Zimbabwe Multiple Indicator Monitoring Survey 2009, we find that household heads’ affiliation with apostolic faith put children under five years old at greater risk of death compared to other religious groups. This effect remains strong even after controlling for a wide range of socio-economic and demographics characteristics of the households in multivariate logit regressions.

Size dimorphism and sexual segregation in pheasants: tests of three competing hypotheses.

Fine scale sexual segregation outside of the mating season is common in sexually dimorphic and polygamous species, particularly in ungulates. A number of hypotheses predict sexual segregation but these are often contradictory with no agreement as to a common cause, perhaps because they are species specific. We explicitly tested three of these hypotheses which are commonly linked by a dependence on sexual dimorphism for animals which exhibit fine-scale sexual segregation; the Predation Risk Hypothesis, the Forage Selection Hypothesis, and the Activity Budget Hypothesis, in a single system the pheasant, Phasianus colchicus; a large, sedentary bird that is predominantly terrestrial and therefore analogous to ungulates rather than many avian species which sexually segregate. Over four years we reared 2,400 individually tagged pheasants from one day old and after a period of 8–10 weeks we released them into the wild. We then followed the birds for 7 months, during the period that they sexually segregate, determined their fate and collected behavioural and morphological measures pertinent to the hypotheses. Pheasants are sexually dimorphic during the entire period that they sexually segregate in the wild; males are larger than females in both body size and gut measurements. However, this did not influence predation risk and predation rates (as predicted by the Predation Risk Hypothesis), diet choice (as predicted by the Forage Selection Hypothesis), or the amount of time spent foraging, resting or walking (as predicted by the Activity Budget Hypothesis). We conclude that adult sexual size dimorphism is not responsible for sexual segregation in the pheasant in the wild. Instead, we consider that segregation may be mediated by other, perhaps social, factors. We highlight the importance of studies on a wide range of taxa to help further the knowledge of sexual segregation.

A longitudinal exploration of the relationship between pornography use and sexual permissiveness in female and male adolescents

IntroductionThere are concerns that pornography use increases adolescents' sexual permissiveness, leading to sexual risk-taking. In contrast to most longitudinal explorations of the relationship between adolescent pornography use and sexual permissiveness, which were carried out in highly liberal and permissive societies, we aimed to re-assess the target relationship in a more traditional, highly religious society. MethodsInformed by the social learning and selective exposure theoretical underpinnings, we used two independent panels of Croatian female and male adolescents (on average 16 years old) to assess the association over 18 and 24 months. Online surveying was used in the Zagreb (n = 372) and classroom-based surveying in the Rijeka panels (n = 753). ResultsParticipants reported relatively low levels of permissiveness, but substantial pornography use—particularly adolescent men. Contrary to earlier studies, we observed no significant paths leading from pornography use to sexual permissiveness. The paths leading from sexual permissiveness to pornography use were significant only among female participants in the Zagreb sample and male participants in the Rijeka sample. However, significant and positive covariances between the two constructs suggested the role of unobserved variables. ConclusionsIn line with the selective exposure hypothesis and the integrative models, this study's findings challenge the notion that pornography use increases sexual permissiveness among adolescents. Although this is reassuring, comprehensive sexuality education and media literacy programs remain important tasks for educational policy in the Information age.