Widespread Signals of Convergent Adaptation to High Altitude in Asia and America

Living at high altitude is one of the most difficult challenges that humans had to cope with during their evolution. Whereas several genomic studies have revealed some of the genetic bases of adaptations in Tibetan, Andean, and Ethiopian populations, relatively little evidence of convergent evolution to altitude in different continents has accumulated. This lack of evidence can be due to truly different evolutionary responses, but it can also be due to the low power of former studies that have mainly focused on populations from a single geographical region or performed separate analyses on multiple pairs of populations to avoid problems linked to shared histories between some populations. We introduce here a hierarchical Bayesian method to detect local adaptation that can deal with complex demographic histories. Our method can identify selection occurring at different scales, as well as convergent adaptation in different regions. We apply our approach to the analysis of a large SNP data set from low- and high-altitude human populations from America and Asia. The simultaneous analysis of these two geographic areas allows us to identify several candidate genome regions for altitudinal selection, and we show that convergent evolution among continents has been quite common. In addition to identifying several genes and biological processes involved in high-altitude adaptation, we identify two specific biological pathways that could have evolved in both continents to counter toxic effects induced by hypoxia.

Trajectories of psychological adaptation to marital breakup after a long-term marriage

While the negative effects of divorce on well-being are well documented in research literature, the large individual differences in psychological adaptation over time are still not well understood. This is especially the case for marital breakup after long-term marriage, which is still a neglected research topic. Against this background, the aim of the present contribution is to shed light on the various trajectories of psychological adaptation to marital breakup after a long-term relationship. Data stem from a longitudinal survey study, which is part of the Swiss National Centre of Competence in Research ‘LIVES – Overcoming vulnerability: life course perspectives’ (funded by the Swiss National Science Foundation). Our analyses are based on results of an exploratory latent profile analysis performed at the first assessment in 2012 among 308 divorced participants aged 45 – 65 years, who divorced after an average of 25 years of marriage (Perrig-Chiello, Hutchison, & Morselli, 2014). Five different groups regarding psychological adaptation to marital breakup (i.e. life satisfaction, depression, hopelessness, subjective health, and mourning) were identified. They were composed of two larger groups of individuals that adapted quite well or very well (“average copers”, n=151 and “resilients”, n=90) and of three smaller groups with major difficulties to adjust to the new situation (“vulnerables”, n= 18; “malcontens”, n= 37 and “resigned ones”, n=12). Clusters differed statistically significant regarding personality variables, time since separation, current relationship status, and financial situation. In the present contribution, we want to investigate the course of adaptation of the five classes two years later by using latent transition analysis. Furthermore, we aim to examine which variables in terms of personality, relationship status, variables of the context of the separation and socio-demographic variables are crucial for change or stability in levels of adaptation in the different classes. The evaluation of the trajectories of adaptation to this critical life event and the identification of variables that enhance the adaptation over time is essential for developing more differentiated measures in counselling as well as intervention techniques in clinical and social services.

Trajectories of psychological adaptation to marital breakup after a long-term marriage

Background: Marital dissolution is known to be among the most stressful life events with long- reaching negative consequences on individuals’ lives. A limitation in research to date is that most studies have focused on the impact of marital disruption on well-being outcomes in younger adults. Furthermore, although population-based studies on divorce document a broad range of negative effects, more fine-grained analyses reveal a large heterogeneity in people’s adjustment, which is still not well understood. Objective: To explore trajectories of psychological adaptation to marital breakup after a long-term marriage, and to examine variables accounting for recovery or chronicity in terms of intrapersonal resources (personality, trait resilience, personal growth), relationship variables (satisfaction with ex- relationship, length of marriage, time since divorce) and socio-demographic variables (age, gender, financial situation). Methods: Latent transition analysis is used to examine the course of psychological adaptation (i.e., depressive symptoms, life satisfaction, hopelessness, mourning and subjective health) to divorce over two years among five profiles of 308 divorcees (mean age: 55.6 years; average duration of former marriage: 23.62 years): Two larger groups of individuals, the one which adapted very well (‘resilients’, 29%), the other quite well (‘average copers’, 49%), and three groups with major difficulties (‘vulnerables’, 6%; ‘malcontents’, 12%; and ‘resigned’, 4%). In a second step the differences among transition patterns were explored on the basis of the distal variables (i.e., intrapersonal resources, relationship variables, socio-demographics). Results: Although the probability of upward changes was higher for those individuals with lower adaptation at time 1, only a small number of individuals made an upward change from the maladapted to the well-adapted groups throughout the two years. The groups of copers and resilients remained stable in their psychological adaption. The most consistent results related to upward changes were intrapersonal resources, namely the NEO personality traits and trait resilience. Conclusion: The majority of individuals divorcing after a long-term marriage adapt successfully over time. Adaptation trajectories depend primarily on intrapersonal resources. However, a minority of divorcees exhibit enduring difficulties. Knowledge about the diversity of these trajectories of vulnerability could be of great help for designing psychological interventions to better tackle this critical life event.

Fast-twitch skeletal muscle fiber adaptation to SERCA1 deficiency in a Dutch Improved Red and White calf pseudomyotonia case.

Missense mutations in ATP2A1 gene, encoding SERCA1 protein, cause a muscle disorder designed as congenital pseudomyotonia (PMT) in Chianina and Romagnola cattle or congenital muscular dystonia1 (CMD1) in Belgian Blue cattle. Although PMT is not life-threatening, CMD1 affected calves usually die within a few weeks of age as a result of respiratory complication. We have recently described a muscular disorder in a double muscle Dutch Improved Red and White cross-breed calf. Mutation analysis revealed an ATP2A1 mutation identical to that described in CMD1, even though clinical phenotype was quite similar to that of PMT. Here, we provide evidence for a deficiency of mutated SERCA1 in PMT affected muscles of Dutch Improved Red and White calf, but not of its mRNA. The reduced expression of SERCA1 is selective and not compensated by the SERCA2 isoform. By contrast, pathological muscles are characterized by a broad distribution of mitochondrial markers in all fiber types, not related to intrinsic features of double muscle phenotype and by an increased expression of sarcolemmal calcium extrusion pump. Calcium removal mechanisms, operating in muscle fibers as compensatory response aimed at lowering excessive cytoplasmic calcium concentration caused by SERCA1 deficiency, could explain the difference in severity of clinical signs.

Hand in hand: public endorsement of climate change mitigation and adaptation

This research investigated how an individual’s endorsements of mitigation and adaptation relate to each other, and how well each of these can be accounted for by relevant social psychological factors. Based on survey data from two European convenience samples (N = 616 / 309) we found that public endorsements of mitigation and adaptation are strongly associated: Someone who is willing to reduce greenhouse gas emissions (mitigation) is also willing to prepare for climate change impacts (adaptation). Moreover, people endorsed the two response strategies for similar reasons: People who believe that climate change is real and dangerous, who have positive attitudes about protecting the environment and the climate, and who perceive climate change as a risk, are willing to respond to climate change. Furthermore, distinguishing between (spatially) proximal and distant risk perceptions suggested that the idea of portraying climate change as a proximal (i.e., local) threat might indeed be effective in promoting personal actions. However, to gain endorsement of broader societal initiatives such as policy support, it seems advisable to turn to the distant risks of climate change. The notion that “localising” climate change might not be the panacea for engaging people in this domain is discussed in regard to previous theory and research.

Tracking the origins of Yakutian horses and the genetic basis for their fast adaptation to subarctic environments

Yakutia, Sakha Republic, in the Siberian Far East, represents one of the coldest places on Earth, with winter record temperatures dropping below -70 °C. Nevertheless, Yakutian horses survive all year round in the open air due to striking phenotypic adaptations, including compact body conformations, extremely hairy winter coats, and acute seasonal differences in metabolic activities. The evolutionary origins of Yakutian horses and the genetic basis of their adaptations remain, however, contentious. Here, we present the complete genomes of nine present-day Yakutian horses and two ancient specimens dating from the early 19th century and ∼5,200 y ago. By comparing these genomes with the genomes of two Late Pleistocene, 27 domesticated, and three wild Przewalski's horses, we find that contemporary Yakutian horses do not descend from the native horses that populated the region until the mid-Holocene, but were most likely introduced following the migration of the Yakut people a few centuries ago. Thus, they represent one of the fastest cases of adaptation to the extreme temperatures of the Arctic. We find cis-regulatory mutations to have contributed more than nonsynonymous changes to their adaptation, likely due to the comparatively limited standing variation within gene bodies at the time the population was founded. Genes involved in hair development, body size, and metabolic and hormone signaling pathways represent an essential part of the Yakutian horse adaptive genetic toolkit. Finally, we find evidence for convergent evolution with native human populations and woolly mammoths, suggesting that only a few evolutionary strategies are compatible with survival in extremely cold environments.

Detection of convergent genome-wide signals of adaptation to tropical forests in humans

Tropical forests are believed to be very harsh environments for human life. It is unclear whether human beings would have ever subsisted in those environments without external resources. It is therefore possible that humans have developed recent biological adaptations in response to specific selective pressures to cope with this challenge. To understand such biological adaptations we analyzed genome-wide SNP data under a Bayesian statistics framework, looking for outlier markers with an overly large extent of differentiation between populations living in a tropical forest, as compared to genetically related populations living outside the forest in Africa and the Americas. The most significant positive selection signals were found in genes related to lipid metabolism, the immune system, body development, and RNA Polymerase III transcription initiation. The results are discussed in the light of putative tropical forest selective pressures, namely food scarcity, high prevalence of pathogens, difficulty to move, and inefficient thermoregulation. Agreement between our results and previous studies on the pygmy phenotype, a putative prototype of forest adaptation, were found, suggesting that a few genetic regions previously described as associated with short stature may be evolving under similar positive selection in Africa and the Americas. In general, convergent evolution was less pervasive than local adaptation in one single continent, suggesting that Africans and Amerindians may have followed different routes to adapt to similar environmental selective pressures.

Psychological adaptation to spousal bereavement in old age. The role of trait resilience, marital history, and context of death

This research examined the effect of marital status and gender on various indicators of psychological adaptation, namely depressive symptoms, loneliness, and life satisfaction. It further explores the role of trait resilience, marital history, and context of death for predicting These outcomes in bereaved individuals. Four hundred eighty widowed individuals aged between 60 and 89 were compared with 759 married peers. Main effects were found for marital status and gender for all indicators. The regression analyses illustrate the multifaceted structure of psychological adaptation. Trait resilience is a key factor in adapting to spousal bereavement, whereas marital history and the context are secondary.

Psychische Adaptation nach Verwitwung im Alter : die Rolle personaler Ressourcen und kontextueller Faktoren (Mantelpapier)

Verwitwung stellt ein typisches und dennoch sehr stressreiches kritisches Lebensereignis des späteren Lebensalters dar. Die Forschung zeigt, dass Betroffene Einbussen in verschiedenen Dimensionen des Wohlbefindens im Vergleich zu verheirateten Gleichaltrigen aufweisen. Die Stärke und Dauer dieser negativen Folgen ist jedoch sehr individuell. Sowohl die Multidimensionalität des Wohlbefindens wie auch die Variabilität in der psychischen Adaptation nach Verwitwung wurden in der bisherigen Forschung überwiegend vernachlässigt. Ausgehend davon ist es das Ziel der vorliegenden Inauguraldissertation, die Folgen der Verwitwung für das Wohlbefinden wie auch die individuellen Unterschiede in der psychischen Adaptation differentiell – unter Berücksichtigung von emotionalen, kognitiven, sozialen und physischen Indikatoren – zu untersuchen. Basierend auf einer interaktionistischen Perspektive werden dabei sowohl personale Ressourcen als auch beziehungs-­‐ und verlustbezogene sowie sozio-­‐historische Faktoren als mögliche Determinanten der psychischen Adaptation nach Verwitwung im Alter berücksichtigt. Auf der Grundlage empirischer Daten zweier Forschungsprojekte des Nationalen Forschungsschwerpunkts LIVES zu Partnerschaft und Altern in der Schweiz, wurden zu diesem Ziel vier Artikel veröffentlicht. Diese bestätigen das im Mittel tiefere emotionale, kognitive und soziale Wohlbefinden Verwitweter, wobei das Ausmass dieser Einbussen stark individuell variiert, besonders abhängig von den verfügbaren intrapersonalen Ressourcen. Der Vergleich über dreissig Jahre zeigt, dass sich die sozialen und wirtschaftlichen Fortschritte dieser Zeit besonders für Frauen günstig auf die Herausforderungen der Verwitwung im Alter ausgewirkt haben. Die psychische Bewältigung jedoch zeigt sich unabhängig von den gesellschaftlichen Rahmenbedingungen und so bestätigt sich die Verwitwung – zumindest aus psychologischer Sicht – als eine der grossen Herausforderungen des Alters. Die Artikel werden im vorliegenden Manteltext in den zugrundeliegenden Forschungsstand und theoretischen Zugang eigebettet, ihre Ergebnisse thematisch zusammengefasst, diskutiert und Implikationen für weitere Forschung und Praxis abgeleitet.

Diagnosing institutional barriers and opportunities for adaptation to climate change

Institutions are one of the decisive factors which enable, constrain and shape adaptation to the impacts of climate change, variability and extreme events. However, current understanding of institutions in adaptation situations is fragmented across the scientific community, evidence diverges, and cumulative learning beyond single studies is limited. This study adopts a diagnostic approach to elaborate a nuanced understanding of institutional barriers and opportunities in climate adaptation by means of a model-centred meta-analysis of 52 case studies of public climate adaptation in Europe. The first result is a novel taxonomy of institutional attributes in adaptation situations. It conceptually organises and decomposes the many details of institutions that empirical research has shown to shape climate adaptation. In the second step, the paper identifies archetypical patterns of institutional traps and trade-offs which hamper adaptation. Thirdly, corresponding opportunities are identified that enable actors to alleviate, prevent or overcome specific institutional traps or trade-offs. These results cast doubt on the validity of general institutional design principles for successful adaptation. In contrast to generic principles, the identified opportunities provide leverage to match institutions to specific governance problems that are encountered in specific contexts. Taken together, the results may contribute to more coherence and integration of adaptation research that we need if we are to foster learning about the role of institutions in adaptation situations in a cumulative fashion.

Drought Adaptation in Millets

Millets are major food and feed sources in the developing world especially in the semi-arid tropical regions of Africa and Asia. The most widely cultivated millets are pearl millet [Pennisetum glaucum (L.) R. Br.], finger millet [Eleusine coracana (L.) Gaertn], foxtail millet [Setaria italica (L.) P. Beauvois], Japanese barnyard millet [Echinochloa esculneta (A. Braun) H. Scholz], Indian Barnyard millet [Echinochloa frumetacea Link], kodo millet [Paspalum scrobiculatum L.], little millet [Panicum sumatrense Roth.ex.Roem. & Schult.], proso millet [Panicum miliaceum L.], tef [Eragrostis tef (Zucc.) Trotter] and fonio or acha [Digitaria exilis (Kippist) Stapf and D. iburua Stapf]. Millets are resilient to extreme environmental conditions especially to inadequate moisture and are rich in nutrients. Millets are also considered to be a healthy food, mainly due to the lack of gluten (a substance that causes coeliac disease) in their grain. Despite these agronomic, nutritional and health-related benefits, millets produce very low yield compared to major cereals such as wheat and rice. This extremely low productivity is related to the challenging environment in which they are extensively cultivated and to the little research investment in these crops. Recently, several national and international initiatives have begun to support the improvement of diverse millet types.