The evolution of early-life effects on social behaviour-why should social adversity carry over to the future?

Numerous studies have shown that social adversity in early life can have long-lasting consequences for social behaviour in adulthood, consequences that may in turn be propagated to future generations. Given these intergenerational effects, it is puzzling why natural selection might favour such sensitivity to an individual's early social environment. To address this question, we model the evolution of social sensitivity in the development of helping behaviours, showing that natural selection indeed favours individuals whose tendency to help others is dependent on early-life social experience. In organisms with non-overlapping generations, we find that natural selection can favour positive social feedbacks, in which individuals who received more help in early life are also more likely to help others in adulthood, while individuals who received no early-life help develop low tendencies to help others later in life. This positive social sensitivity is favoured because of an intergenerational relatedness feedback: patches with many helpers tend to be more productive, leading to higher relatedness within the local group, which in turn favours higher levels of help in the next generation. In organisms with overlapping generations, this positive feedback is less likely to occur, and those who received more help may instead be less likely to help others (negative social feedback). We conclude that early-life social influences can lead to strong between-individual differences in helping behaviour, which can take different forms dependent on the life history in question. This article is part of the theme issue 'Developing differences: early-life effects and evolutionary medicine'

Experimental evidence for a causal effect of pair-bond duration on reproductive performance in oystercatchers (Haematopus ostralegus)

Many studies have suggested that reproductive performance improves during the pair-bond, which might explain why individuals remate with the same partner in many species. However, discussion exists about whether the association between reproductive performance and pair-bond duration that is reported in these studies reflects a causal relationship. Usually it is unclear whether a positive association is caused by pairs improving during their pair-bond or by high-quality pairs staying together for longer. Furthermore, reproductive performance often also depends on the age or breeding experience of parents, which all covary with pair-bond duration. A much needed experimental approach is lacking so far. We investigated the effect of pair-bond duration on reproductive performance in a long-lived monogamous bird species based on natural as well as experimental variation. The duration of oystercatcher (Haematopus ostralegus) pair-bonds, which were followed for 21 years, strongly affected reproductive output, even after controlling for effects of age and breeding experience. Pairs improved during their pair-bond, and there were no indications of selective disappearance of low-quality pairs; however, pairs that stayed together for very long performed badly. Experimental removal of one partner showed that the reproductive cost of divorce depended on the pair-bond duration with the old partner. In addition, after remating, the newly formed pairs strongly improved again, independent of the age and breeding experience of the remated pair members. As such, this study provides the first experimental evidence of a causal effect of pair-bond duration on reproductive performanc

Covered Stents vs. Angioplasty for Common Iliac Artery In Stent Restenosis:A Retrospective Comparison

Objective: The optimal endovascular treatment for common iliac artery in stent re-stenosis has yet to be assessed. Treatment options include, among others, angioplasty alone and repeated stenting with covered stents. Methods: This study retrospectively compared patency and target lesion revascularisation of these treatments. All patients who underwent endovascular treatment of common iliac artery in stent re-stenosis between 2007 and 2017 were included retrospectively. The primary end point was freedom from re-stenosis. Secondary endpoints were target lesion revascularisation rate (TLR) and freedom from occlusion during follow up. Results: Seventy-four interventions were included, consisting of 37 angioplasties and 37 covered stent placements in 57 patients. Freedom from re-stenosis at four years was 72.6% (95% confidence interval [CI] 51.8% – 88.7%) in the covered stent group vs. 43.5% (95% CI 25.9% – 59.8%) in the percutaneous transluminal angioplasty (PTA) group (p = .003). The target lesion revascularisation (TLR) rate was 16.4% (95% CI 7.1% – 35.6%) and 43.6% (95% CI 28.0% – 63.2%) respectively (p = .020). There was no difference in freedom from occlusion; this was 90.8% (95% CI 73.9% – 97.0%) in the covered stent group and 79.1% (95% CI 58.4% – 90.3%) in the PTA group (p = .49). The difference in freedom from re-stenosis and TLR remained significant after sensitivity and multivariable analyses. Conclusion: Covered stents offer better outcomes for common iliac artery in stent re-stenosis than angioplasty alone

Developing differences: early-life effects and evolutionary medicine

Variation in early-life conditions can trigger developmental switches that lead to predictable individual differences in adult behaviour and physiology. Despite evidence for such early-life effects being widespread both in humans and throughout the animal kingdom, the evolutionary causes and consequences of this developmental plasticity remain unclear. The current issue aims to bring together studies of early-life effects from the fields of both evolutionary ecology and biomedicine to synthesise and advance current knowledge of how information is used during development, the mechanisms involved, and how early-life effects evolved. We hope this will stimulate further research into early-life effects, improving our understanding of why individuals differ and how this might influence their susceptibility to disease. This article is part of the theme issue ‘Developing differences: early-life effects and evolutionary medicine’.</p

Diez reglas sencillas para una exitosa colaboración transdisciplinar

El presente artículo es la versión en castellano de la publicación: KNAPP, B.; BARDENET, R.; BERNABEU, M.O.; BORDAS, R.; BRUNA, M.; CALDERHEAD, B. ET AL. (2015) “Ten Simple Rules for a Successful Cross-Disciplinary Collaboration”. PLoS Comput Biol 11(4): e1004214, disponible en: https://doi.org/10.1371/journal.pcbi.1004214. La traducción, autorizada por la entidad editora, ha sido llevada a cabo por Ona Lorda Roure y Leila Adim, colaboradoras del Instituto de Investigación TransJus y supervisada por el Dr. Juli Ponce Solé, Director del TransJus. En la misma se han incluido algunas notas aclaratorias para el lector en español, así como bibliografía complementaria en español.[spa] En el auge de las colaboraciones interdisciplinarias entre los distintos campos científicos, la transdisciplinariedad se presenta como la clave para encontrar soluciones a una variedad de problemas globales. Este trabajo, situado en el marco de la biología informática, se centra en exponer una lista extensa de reglas y consejos útiles para lograr una exitosa sinergia entre los varios colaboradores de un proyecto transdisciplinar. Se trata, de hecho, de una guía que pretende dirigirse tanto a investigadores noveles como a aquellos investigadores consolidados que se adentran en un espacio transdisciplinar por primera vez. En particular, este trabajo expone los beneficios principales de establecer una colaboración transdisciplinar, así como los problemas que de ella puedan surgir.[cat] En l'auge de les col·laboracions interdisciplinàries entre els diferents camps científics, la transdisciplinarietat es presenta com la clau per trobar solucions a una varietat de problemes globals. Aquest treball, situat en el marc de la biologia informàtica, es centra en exposar una llista extensa de regles i consells útils per aconseguir una reeixida sinergia entre els varis col·laboradors d'un projecte transdisciplinar. Es tracta, de fet, d'una guia que pretén dirigir-se tant a recercadors novells com a aquells recercadors consolidats que s'endinsen en un espai transdisciplinar per primera vegada. En particular, aquest treball exposa els beneficis principals d'establir una col·laboració transdisciplinar, així com els problemes que d'ella puguin sorgir.[eng] At a time of increasing interdisciplinary collaboration between different scientific fields, cross-disciplinarity represents a key for finding solutions to a variety of global problems. This work, located within the framework of computer biology, focuses on exposing an extensive list of rules and useful tips to achieve a successful synergy among the various collaborators of a transdisciplinary project. It is, in fact, a guide aimed at addressing both first-time researchers and consolidated researchers who enter a transdisciplinary space for the first time. In particular, this work exposes the main benefits of establishing a cross-disciplinary collaboration, as well as the problems that may arise from it

Ten Simple Rules for a Successful Cross-Disciplinary Collaboration

Cross-disciplinary collaborations have become an increasingly important part of science. They are seen as key if we are to find solutions to pressing, global-scale societal challenges, including green technologies, sustainable food production, and drug development. Regulators and policy- makers have realized the power of such collaborations, for example, in the 80 billion Euro "Horizon 2020" EU Framework Programme for Research and Innovation. This programme puts special emphasis on “breaking down barriers to create a genuine single market for knowledge, research and innovation

When to rely on maternal effects and when on phenotypic plasticity?

Existing insight suggests that maternal effects have a substantial impact on evolution, yet these predictions assume that maternal effects themselves are evolutionarily constant. Hence, it is poorly understood how natural selection shapes maternal effects in different ecological circumstances. To overcome this, the current study derives an evolutionary model of maternal effects in a quantitative genetics context. In constant environments, we show that maternal effects evolve to slight negative values that result in a reduction of the phenotypic variance (canalization). By contrast, in populations experiencing abrupt change, maternal effects transiently evolve to positive values for many generations, facilitating the transmission of beneficial maternal phenotypes to offspring. In periodically fluctuating environments, maternal effects evolve according to the autocorrelation between maternal and offspring environments, favoring positive maternal effects when change is slow, and negative maternal effects when change is rapid. Generally, the strongest maternal effects occur for traits that experience very strong selection and for which plasticity is severely constrained. By contrast, for traits experiencing weak selection, phenotypic plasticity enhances the evolutionary scope of maternal effects, although maternal effects attain much smaller values throughout. As weak selection is common, finding substantial maternal influences on offspring phenotypes may be more challenging than anticipated

megabyte22/conflict_maternal_effects: Maternal Effects and Parent-Offspring Conflict

Initial releas

Conflict over condition-dependent sex allocation can lead to mixed sex-determination systems

Theory suggests that genetic conflicts drive turnovers between sex-determining mechanisms, yet these studies only apply to cases where sex allocation is independent of environment or condition. Here, we model parent–offspring conflict in the presence of condition-dependent sex allocation, where the environment has sex-specific fitness consequences. Additionally, one sex is assumed to be more costly to produce than the other, which leads offspring to favor a sex ratio less biased toward the cheaper sex in comparison to the sex ratio favored by mothers. The scope for parent–offspring conflict depends on the relative frequency of both environments: when one environment is less common than the other, parent–offspring conflict can be reduced or even entirely absent, despite a biased population sex ratio. The model shows that conflict-driven invasions of condition-independent sex factors (e.g., sex chromosomes) result either in the loss of condition-dependent sex allocation, or, interestingly, lead to stable mixtures of condition-dependent and condition-independent sex factors. The latter outcome corresponds to empirical observations in which sex chromosomes are present in organisms with environment-dependent sex determination. Finally, conflict can also favor errors in environmental perception, potentially resulting in the loss of condition-dependent sex allocation without genetic changes to sex-determining loci