The gradual extinction of transferred avoidance stimulus functions

We investigated the transfer of conditioned avoidance functions through equivalence relations, and the extinction of these functions, facilitated by verbal prompts. Nine participants acquired three 4-member stimulus equivalence classes using a matching-to-sample procedure. One class stimulus was paired, by classical conditioning, with an aversive tone, which was used in avoidance training of a distinct response. There were two groups: A established the equivalence classes before avoidance training and vice versa for B. During some avoidance trials, each stimulus presentation was followed by the request for a verbal estimation of the probability of the tone. The last trials, run in extinction, included a verbal prompt to corroborate the provided estimation. One participant in each group received no verbal prompts. To negate the necessary reliance on instructions-governed performance, an additional participant completed the experiment with minimal instructions. All participants who had the equivalence training prior to the conditioning showed within-class transfer of avoidance functions, in contrast to the others. All prompted participants who demonstrated transfer showed gradual response extinction, but with a differential gradient. Responding decreased more sharply to the indirectly related stimuli than to the directly paired stimuli. The clinical implications are discussed

Measuring heritability: why bother?

Uchiyama et al. rightly consider how cultural variation may influence estimates of heritability by contributing to environmental sources of variation. We disagree, however, with the idea that estimates of heritability are ever a plausible aim. Heritability estimates are always context-specific, and to suggest otherwise is to misunderstand what heritability can and cannot tell us

Why is greater income inequality associated with lower life satisfaction and poorer health? Evidence from the European Quality of Life Survey, 2012

Greater income inequality is associated with lower average wellbeing. There are multiple possible explanations for this pattern. We use data from the European Quality of Life Survey 2012 (27,571 respondents from 28 countries) to evaluate the contributions of different causal pathways to associations between national income inequality and wellbeing. In unadjusted analyses, greater income inequality was associated with lower life satisfaction and poorer self-rated health. For life satisfaction, 43% of the association was attributable to individual income effects, and 41% to worse public services (especially access to healthcare). The association between income inequality and self-rated health was mainly (68%) due to individual income effects. For life satisfaction but not self-rated health, we found some evidence of costs of inequality that fall on those with high incomes. We conclude that the negative associations between income inequality and wellbeing across European countries are substantially, but not entirely, due to individual income effects

Birthweight and paternal involvement predict early reproduction in British women: evidence from the National Child Development Study

There is considerable interest in the mechanisms maintaining early reproduction in the most socioeconomically disadvantaged groups in developed countries. Previous research has suggested that differential exposure to early-life factors such as low birthweight and lack of paternal involvement during childhood may be relevant. Here, we used longitudinal data on the female cohort members from the UK National Child Development Study (n=3014-4482 depending upon variables analysed) to investigate predictors of early reproduction. Our main outcome measures were having a child by age 20, and stating at age 16 an intended age of reproduction of 20 years or lower. Low paternal involvement during childhood was associated with increased likelihood of early reproduction (O.R. 1.79-2.25) and increased likelihood of early intended reproduction (O.R. 1.38-2.50). Low birthweight for gestational age also increased the odds of early reproduction (O.R. for each additional s.d. 0.88) and early intended reproduction (O.R. for each additional s.d. 0.81). Intended early reproduction strongly predicted actual early reproduction (O.R. 5.39, 95% CI 3.71-7.83). The results suggest that early-life factors such as low birthweight for gestational age, and low paternal involvement during childhood, may affect women?s reproductive development, leading to earlier target and achieved ages for reproduction. Differential exposure to these factors may be part of the reason that early fertility persists in socioeconomically disadvantaged groups. We discuss our results with respect to the kinds of interventions likely to affect the rate of teen pregnancy

Turning the tide: rhythmic aggregation behaviour in Anurida maritima (Collembola) is entrained by inundation

Numerous foreshore species evolved the ability to predict tidal change and adjust behaviour and metabolism accordingly. The intertidal collembolan Anurida maritima (Guérin-Méneville, 1836) shows endogenously controlled rhythmic changes in behaviour that anticipate the tides. Animals forage during low tide and hide in large aggregations in the substrate during high tide. Here, artificial tidal environments and time-lapse photography were used to investigate if this behaviour is responsive to key environmental cues. It is shown that the precise rhythmicity of aggregation behaviour is dependent on periodic inundations. In the absence of such inundations, rhythmic aggregation patterns dissipate and are no longer accurate after 14 days. Slowly shifting the artificial tides, showed that rhythmic aggregation behaviour in A. maritima is responsive and adjusts to a newly-imposed tidal regimen. This suggests that the species has the ability to synchronise to newly encountered tidal conditions under natural conditions. The findings provide a robust foundation for advancing detailed chronobiological research on A. maritima as a model organism to gain a deeper understanding of biological time-keeping

The Ruthwell and Bewcastle Crosses

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Patterns of physical and psychological development in future teenage mothers

Background and objectives: Teenage childbearing may have childhood origins and can be viewed as the outcome of a coherent reproductive strategy associated with early environmental conditions. Life-history theory would predict that where futures are uncertain fitness can be maximized through diverting effort from somatic development into reproduction. Even before the childbearing years, future teenage mothers differ from their peers both physically and psychologically, indicating early calibration to key ecological factors. Cohort data has not been deliberately collected to test life-history hypotheses within Western populations. None the less, existing data sets can be used to pursue relevant patterns using socioeconomic variables as indices of relevant ecologies. Methodology: We examined the physical and psychological development of 599 young women from the National Child Development Study who became mothers before age 20, compared to 599 socioeconomically matched controls. Results: Future young mothers were lighter than controls at birth and shorter at age 7. They had earlier menarche and accelerated breast development, earlier cessation of growth, and shorter adult stature. Future young mothers had poorer emotional and behavioural adjustment than controls at age 7 and especially 11, and by age 16, idealised younger ages for marriage and parenthood than did the controls. Conclusions and implications: The developmental patterns we observed are consistent with the idea that early childbearing is a component of an accelerated reproductive strategy that is induced by early-life conditions. We discuss the implications for the kinds of interventions likely to affect the rate of teenage childbearing

The niche construction perspective: a critical appraisal

Niche construction refers to the activities of organisms that bring about changes in their environments, many of which are evolutionarily and ecologically consequential. Advocates of niche construction theory (NCT) believe that standard evolutionary theory fails to recognize the full importance of niche construction, and consequently propose a novel view of evolution, in which niche construction and its legacy over time (ecological inheritance) are described as evolutionary processes, equivalent in importance to natural selection. Here, we subject NCT to critical evaluation, in the form of a collaboration between one prominent advocate of NCT, and a team of skeptics. We discuss whether niche construction is an evolutionary process, whether NCT obscures or clarifies how natural selection leads to organismal adaptation, and whether niche construction and natural selection are of equivalent explanatory importance.We also consider whether the literature that promotes NCT overstates the significance of niche construction, whether it is internally coherent, and whether it accurately portrays standard evolutionary theory. Our disagreements reflect a wider dispute within evolutionary theory over whether the neo-Darwinian synthesis is in need of reformulation, as well as different usages of some key terms (e.g., evolutionary process)

Size Acceptance: A Discursive Analysis of Online Blogs

This document is an Accepted Manuscript of an article published by Taylor & Francis Group in Fat Studies on 25 May 2018, available online at: https://doi.org/10.1080/21604851.2018.1473704. Under embargo until 25 May 2019.Dominant discourses of “fatness” and “fat people” have implications for physical and mental health. Although alternative discourses such as “size acceptance” exist, there has been little consideration of the ways in which these alternative arguments (and speakers) may be positioned to be heard. Using a discursive thematic analysis, the authors demonstrate that size acceptance online bloggers have created a community online that enables them to persuasively provide alternative claims to “expertise,” which positions their views as credible and legitimate alternatives to those of more established authority figures—such as health professionals. This has implications not only for the lived experience of fat people, but also for researchers by emphasizing the importance of exploring not just what is said, but how, if we are to understand how different articulated positions are to be persuasive.Peer reviewe