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Dew and frost do not serve as water sources for rock-dwelling organisms in the Dry Valleys of AntarcticaNARA Subscribed
Main conclusions Contrary to previous assumptions, dew and frost cannot be regarded as water sources for lithobionts in the McMurdo Dry Valleys (MDV) of Antarctica, which therefore solely rely on snowmelt water for growth. Therefore, and contrary to previous claims, MDV can be regarded as a good analogue for life on Mars. Abstract Rock-dwelling chlorolichens and cyanobacteria provide most of the total biomass of the ice-free z...
Museum Genomics Reveals Temporal Genetic Stasis and Global Genetic Diversity in Arabidopsis thalianaNARA Subscribed
Global patterns of population genetic variation through time offer a window into evolutionary processes that maintain diversity. Over time, lineages may expand or contract their distribution, causing turnover in population genetic composition. At individual loci, migration, drift and selection (among other processes) may affect allele frequencies. Museum specimens of widely distributed species offer a unique window into the ge...
There is considerable evidence for local adaptation in nature, yet important questions remain regarding its genetic basis. How many loci are involved? What are their effect sizes? What is the relative importance of conditional neutrality versus genetic trade‐offs? Here we address these questions in the self‐pollinating, annual plant Arabidopsis thaliana . We used 400 recombinant inbred lines (RILs) derived from two locally ada...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Climate change research and action must look beyond 2100NARA Subscribed
Anthropogenic activity is changing Earth's climate and ecosystems in ways that are potentially dangerous and disruptive to humans. Greenhouse gas concentrations in the atmosphere continue to rise, ensuring that these changes will be felt for centuries beyond 2100, the current benchmark for projection. Estimating the effects of past, current, and potential future emissions to only 2100 is therefore short‐sighted. Critical probl...
Comparative activity and functional ecology of permafrost soils and lithic niches in a hyper‐arid polar desertNARA Subscribed
Summary Permafrost in the high elevation McMurdo Dry Valleys of Antarctica ranks among the driest and coldest on Earth. Permafrost soils appear to be largely inhospitable to active microbial life, but sandstone lithic microhabitats contain a trophically simple but functional cryptoendolithic community. We used metagenomic sequencing and activity assays to examine the functional capacity of permafrost soils and cryptoendolithic...
Roles of Patch Characteristics, Drought Frequency, and Restoration in Long‐Term Trends of a Widespread AmphibianNARA Subscribed
Despite the high profile of amphibian declines and the increasing threat of drought and fragmentation to aquatic ecosystems, few studies have examined long‐term rates of change for a single species across a large geographic area. We analyzed growth in annual egg‐mass counts of the Columbia spotted frog ( Rana luteiventris ) across the northwestern United States, an area encompassing 3 genetic clades. On the basis of data colle...
Summary Drylands are the largest terrestrial biome on Earth and a ubiquitous feature is desert pavement terrain, comprising rocks embedded in the mineral soil surface. Quartz and other translucent rocks are common and microbial communities termed hypoliths develop as biofilms on their ventral surfaces. In extreme deserts these represent major concentrations of biomass, and are emerging as key to geobiological processes and soi...
Summary Hypolithic cyanobacterial communities occur in hot and cold hyperarid environments but the physical factors determining their diversity are not well understood. Here we report hypolithic diversity and colonization of a common quartz substrate at several hyperarid locations in the ancient deserts of north‐western China, that experience varying mean annual temperature, rainfall and concomitant availability of liquid wate...
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