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The Fukushima Daiichi Nuclear Power Plant accident released radionuclides directly into the ocean as a result of the Great East Japan Earthquake on March 11, 2011. This material has been transported across the Pacific Ocean and detected in the northeastern Pacific. We began a surface ocean 129 I monitoring program a few months after this disaster in June 2011, with samples from Scripps Pier, La Jolla, California, USA, with the...
Unraveling intragenomic polymorphisms in the high-quality genome of Hypoxylaceae: a comprehensive study of the rDNA cistronNARA Subscribed
Sequencing ribosomal DNA loci, such as ITS and LSU, are among the first steps to characterize and identify newly isolated fungal strains. Substantial doubt has recently been raised concerning the unequivocal suitability of using this sequence information for inferring inter- and intraspecific relationships, as especially the ITS locus was repeatedly shown to harbor high intragenomic plasticity. The evolutionary mechanisms lead...
Extensive regional variation in the phenology of insects and their response to temperature across N orth A mericaNARA Subscribed
Climate change models often assume similar responses to temperatures across the range of a species, but local adaptation or phenotypic plasticity can lead plants and animals to respond differently to temperature in different parts of their range. To date, there have been few tests of this assumption at the scale of continents, so it is unclear if this is a large‐scale problem. Here, we examined the assumption that insect taxa...
Common, low-frequency, rare, and ultra-rare coding variants contribute to COVID-19 severityNARA Subscribed
The combined impact of common and rare exonic variants in COVID-19 host genetics is currently insufficiently understood. Here, common and rare variants from whole-exome sequencing data of about 4000 SARS-CoV-2-positive individuals were used to define an interpretable machine-learning model for predicting COVID-19 severity. First, variants were converted into separate sets of Boolean features, depending on the absence or the pr...
Ecosystem transpiration and evaporation: Insights from three water flux partitioning methods across FLUXNET sitesNARA Subscribed
We apply and compare three widely applicable methods for estimating ecosystem transpiration ( T ) from eddy covariance (EC) data across 251 FLUXNET sites globally. All three methods are based on the coupled water and carbon relationship, but they differ in assumptions and parameterizations. Intercomparison of the three daily T estimates shows high correlation among methods ( R between .89 and .94), but a spread in magnitudes o...
Intragenomic polymorphisms in the ITS region of high-quality genomes of the Hypoxylaceae (Xylariales, Ascomycota)NARA Subscribed
The internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA) has been established (and is generally accepted) as a primary “universal” genetic barcode for fungi for many years, but the actual value for taxonomy has been heavily disputed among mycologists. Recently, twelve draft genome sequences, mainly derived from type species of the family Hypoxylaceae (Xylariales, Ascomycota) and the ex-epitype strain of Xylaria...
Oceanographic barriers, divergence, and admixture: Phylogeography and taxonomy of two putative subspecies of short‐finned pilot whaleNARA Subscribed
Genomic phylogeography plays an important role in describing evolutionary processes and their geographic, ecological, or cultural drivers. These drivers are often poorly understood in marine environments, which have fewer obvious barriers to mixing than terrestrial environments. Taxonomic uncertainty of some taxa (e.g., cetaceans), due to the difficulty in obtaining morphological data, can hamper our understanding of these pro...
Explaining ecosystem multifunction with evolutionary modelsNARA Subscribed
Ecosystem function is the outcome of species interactions, traits, and niche overlap – all of which are influenced by evolution. However, it is not well understood how the tempo and mode of niche evolution can influence ecosystem function. In evolutionary models where either species differences accumulate through random drift in a single trait or species differences accumulate through divergent selection among close relatives,...
EPMA-World Congress 2015NARA Subscribed
Large‐scale habitat destruction and climate change result in the non‐random loss of evolutionary lineages, reducing the amount of evolutionary history represented in ecological communities. Yet, we have limited understanding of the consequences of evolutionary history on the structure of food webs and the services provided by biological communities. Drawing on 11 years of data from a long‐term plant diversity experiment, we sh...
Phylogenetic diversity promotes ecosystem stabilityNARA Subscribed
Ecosystem stability in variable environments depends on the diversity of form and function of the constituent species. Species phenotypes and ecologies are the product of evolution, and the evolutionary history represented by co‐occurring species has been shown to be an important predictor of ecosystem function. If phylogenetic distance is a surrogate for ecological differences, then greater evolutionary diversity should buffe...
Sharks and other large predators are scarce on most coral reefs, but studies of their historical ecology provide qualitative evidence that predators were once numerous in these ecosystems. Quantifying density of sharks in the absence of humans (baseline) is, however, hindered by a paucity of pertinent time‐series data. Recently researchers have used underwater visual surveys, primarily of limited spatial extent or nonstandard...