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Plectus murrayi is a free-living microbivorous nematode endemic to Antarctic soils. Our draft assembly of its mitogenome was 15,656 bp long, containing 12 protein-coding, eight transfer RNA (tRNA), and two ribosomal RNA (rRNA) genes. Mitophylogenomic analyses extend our understanding of mitochondrial evolution in Nematoda.

As the most abundant animals on earth, nematodes are a dominant component of the soil community. They play critical roles in regulating biogeochemical cycles and vegetation dynamics within and across landscapes and are an indicator of soil biological activity. Here, we present a comprehensive global dataset of soil nematode abundance and functional group composition. This dataset includes 6,825 georeferenced soil samples from all continents and biomes. For geospatial mapping purposes these samples are aggregated into 1,933 unique 1-km pixels, each of which is linked to 73 global environmental covariate data layers. Altogether, this dataset can help to gain insight into the spatial distribution patterns of soil nematode abundance and community composition, and the environmental drivers shaping these patterns.

This article presents a short research report on the relationship between perceived antagonism in social relations measured using the Belief in a Zero-Sum Game (BZSG) scale, life satisfaction, and positive and negative affect. Given that individuals who believe that life is like a zero-sum game are likely to perceive their daily interactions with others as unfair, we expected that individuals with high BZSG experience more negative affect and fewer positive one, resulting in a lower satisfaction with life. In addition, we examined whether country-level BZSG may play a moderating role in these associations. Data were collected from student samples (N = 7146) in 35 countries. Multilevel modelling revealed that perceived social antagonism in social relations is negatively associated with satisfaction with life and that this relationship is mediated by both positive and negative affect at the individual level. The relation of individual BZSG and negative affect on satisfaction with life were weaker in societies with higher country-level BZSG, suggesting that the effects of BZSG may be less detrimental in these countries. These findings extend previous knowledge about predictors of life satisfaction and suggest that social beliefs might also be an important factor that influences subjective well-being. The contribution of the study is that the separate treatment of life satisfaction and positive and negative affect may be helpful in many research situations, particularly from a cross-cultural perspective., Author(s): Joanna Rózycka-Tran [sup.1] , Jaroslaw P. Piotrowski [sup.2] , Magdalena Zemojtel-Piotrowska [sup.2] , Pawel Jurek [sup.1] , Evgeny N. Osin [sup.3] , Byron G. Adams [sup.4] [sup.5] , Rahkman [...]

Background: Overall, youth well-being is crucial, particularly in developmental contexts, such as sub-Saharan Africa, which is experiencing the largest growth in the youth population internationally. The Positive Youth Development (PYD) framework considers the importance of positive experiences, positive relationships and positive environments regarding developmental (further distinguished as internal and external) assets. These assets are important for promoting positive outcomes among youth. Objective: The objective of this study is to examine the importance of developmental assets for academic performance in three sub-Saharan African contexts, represented by Ghana, Kenya, and South Africa. Method: In a cross-sectional study, youth from these three countries completed a questionnaire on sociodemographic measures, such as age, gender, parental education (as a proxy for socioeconomic status), measures of developmental assets and academic performance. We used Analysis of Variance to examine mean differences in developmental assets across countries and academic performance. Results: Results indicated that Ghanaian students reported fewer assets than Kenyan and South African students and that across all countries, adolescents who perform academically better reported more developmental assets, in particular, internal assets. Conclusion: This is one of the few studies, which consider developmental assets within the PYD framework beyond the Western context. While we found that mainly internal assets were associated with academic performance, it is important to reiterate that both internal and external assets are theoretically associated with positive outcomes, such as academic performance. Future research may benefit from testing interventions to improve academic performance in the sub-Saharan African contexts by fostering both types of assets. Research is needed to extend the framework to consider more culturally appropriate and contextually relevant assets.

Our understanding of the fundamental role that soil bacteria play in the structure and functioning of Earth's ecosystems is ever expanding, but insight into the nature of interactions within these bacterial communities remains rudimentary. Bacterial facilitation may enhance the establishment, growth, and succession of eukaryotic biota, elevating the complexity and diversity of the entire soil community and thereby modulating multiple ecosystem functions. Global climate change often alters soil bacterial community composition, which, in turn, impacts other dependent biota. However, the impact of climate change on facilitation within bacterial communities remains poorly understood even though it may have important cascading consequences for entire ecosystems. The wealth of metagenomic data currently being generated gives community ecologists the ability to investigate bacterial facilitation in the natural world and how it affects ecological systems responses to climate change. Here, we review current evidence demonstrating the importance of facilitation in promoting emergent properties such as community diversity, ecosystem functioning, and resilience to climate change in soil bacterial communities. We show that a synthesis is currently missing between the abundant data, newly developed models and a coherent ecological framework that addresses these emergent properties. We highlight that including phylogenetic information, the physicochemical environment, and species‐specific ecologies can improve our ability to infer interactions in natural soil communities. Following these recommendations, studies on bacterial facilitation will be an important piece of the puzzle to understand the consequences of global change on ecological communities and a model to advance our understanding of facilitation in complex communities more generally. [ABSTRACT FROM AUTHOR]

Record high temperatures were documented in the McMurdo Dry Valleys, Antarctica, on 18 March 2022, exceeding average temperatures for that day by nearly 30°C. Satellite imagery and stream gage measurements indicate that surface wetting coincided with this warming more than 2 months after peak summer thaw and likely exceeded thresholds for rehydration and activation of resident organisms that typically survive the cold and dry conditions of the polar fall in a freeze‐dried state. This weather event is notable in both the timing and magnitude of the warming and wetting when temperatures exceeded 0°C at a time when biological communities and streams have typically entered a persistent frozen state. Such events may be a harbinger of future climate conditions characterized by warmer temperatures and greater thaw in this region of Antarctica, which could influence the distribution, activity, and abundance of sentinel taxa. Here we describe the ecosystem responses to this weather anomaly reporting on meteorological and hydrological measurements across the region and on later biological observations from Canada Stream, one of the most diverse and productive ecosystems within the McMurdo Dry Valleys. Plain Language Summary: An atmospheric river event in March 2022 led to record warm temperatures over much of Antarctica. Here we report the ecological and hydrological responses to these extraordinary temperatures. The McMurdo Dry Valleys are unique among other regions of Antarctica that experienced this extreme weather event because contemporary observations of ecosystem responses to unseasonable weather can be anchored to a 30‐year record of meteorology, stream flow, and soil community data supported by the National Science Foundation Long Term Ecological Research program. As such weather anomalies are expected to be more common in future Antarctic climate regimes our insights are broadly relevant to the scientific community seeking to predict future ecosystem and organismal responses to ongoing climate change. Key Points: An atmospheric river caused extreme weather in the Antarctic Dry Valleys in March 2022 with temperatures 25°C above average conditionsRecord fall temperatures drove mobilization of liquid water and reactivation of biota at a time when organisms are entering winter dormancyBiotic responses to unseasonable warm and wet conditions may influence diversity and life‐history characteristics of biotic communities [ABSTRACT FROM AUTHOR]

BackgroundParasitism is a major ecological niche for a variety of nematodes. Multiple nematode lineages have specialized as pathogens, including deadly parasites of insects that are used in biological control. We have sequenced and analyzed the draft genomes and transcriptomes of the entomopathogenic nematode Steinernema carpocapsae and four congeners (S. scapterisci, S. monticolum, S. feltiae, and S. glaseri).ResultsWe used these genomes to establish phylogenetic relationships, explore gene conservation across species, and identify genes uniquely expanded in insect parasites. Protein domain analysis in Steinernema revealed a striking expansion of numerous putative parasitism genes, including certain protease and protease inhibitor families, as well as fatty acid- and retinol-binding proteins. Stage-specific gene expression of some of these expanded families further supports the notion that they are involved in insect parasitism by Steinernema. We show that sets of novel conserved non-coding regulatory motifs are associated with orthologous genes in Steinernema and Caenorhabditis.ConclusionsWe have identified a set of expanded gene families that are likely to be involved in parasitism. We have also identified a set of non-coding motifs associated with groups of orthologous genes in Steinernema and Caenorhabditis involved in neurogenesis and embryonic development that are likely part of conserved protein-DNA relationships shared between these two genera.