Benthic macrofauna are important and widely used biological indicators of marine ecosystems as they have limited mobility and therefore integrate the effects of local environmental stressors over time. Recently, environmental DNA (eDNA) analysis has provided a potentially more resource-efficient approach for benthic biomonitoring than traditional morphology-based methods. Several studies have compared eDNA with morphology-based monitoring, but few have compared the two approaches using the exact same sediment cores.
View Article and Find Full Text PDFLarger effective populations (Ne) are characterized by higher genetic diversity, which is expected to predict population performance (average individual performance that influences fitness). Empirical studies of the relationship between neutral diversity and performance mostly represent species with small Ne, while there is limited data from the species-rich and ecologically important arthropods that are assumed to have large Ne but are threatened by massive declines. We performed a systematic literature search and used meta-analytical models to test the prediction of a positive association between neutral genetic diversity and performance in wild arthropods.
View Article and Find Full Text PDFTerrestrial invertebrates are highly important for the decomposition of dung from large mammals. Mammal dung has been present in many of Earth's ecosystems for millions of years, enabling the evolution of a broad diversity of dung-associated invertebrates that process various components of the dung. Today, large herbivorous mammals are increasingly introduced to ecosystems with the aim of restoring the ecological functions formerly provided by their extinct counterparts.
View Article and Find Full Text PDFEnvironmental DNA (eDNA) has opened promising avenues for establishing standardized, cost-efficient monitoring of biodiversity. However, comprehensive and systematic implementation is urgently needed to address the current biodiversity crisis. Here, we envision a global eDNA biomonitoring scheme, which could potentially revolutionize the understanding and conservation of life on Earth.
View Article and Find Full Text PDFAlthough the Holarctic fauna has been explored for centuries, many questions on its formation are still unanswered. For example, i) what was the impact of the uplift of the Himalaya and Tibetan Plateau?, ii) what were the timings and climate of the faunal bridges connecting the Nearctic and Palearctic regions?, and iii) how did insect lineages respond to the late Paleogene global cooling and regional aridification? To answer these, we developed a phylogenetic dataset of 1229 nuclear loci for a total of 222 species of rove beetles (Staphylinidae) with emphasis in the tribe Quediini, especially Quedius-lineage and its subclade Quedius sensu stricto. Using eight fossils for calibrating molecular clock, we estimated divergence times and then analysed in BioGeoBEARS paleodistributions of the most recent common ancestor for each target lineage.
View Article and Find Full Text PDFTrophic rewilding is increasingly applied in restoration efforts, with the aim of reintroducing the ecological functions provided by large-bodied mammals and thereby promote self-regulating, biodiverse ecosystems. However, empirical evidence for the effects of megafauna introductions on the abundance and richness of other organisms such as plants and invertebrates, and the mechanisms involved still need strengthening. In this study, we use environmental DNA (eDNA) metabarcoding of dung from co-existing feral cattle and horses to assess the seasonal variation in plant diet and dung-associated arthropods and nematodes.
View Article and Find Full Text PDFPopulation genetic data can provide valuable information on the demography of a species. For rare and elusive marine megafauna, samples for generating the data are traditionally obtained from tissue biopsies, which can be logistically difficult and expensive to collect and require invasive sampling techniques. Analysis of environmental DNA (eDNA) offers an alternative, minimally invasive approach to provide important genetic information.
View Article and Find Full Text PDFInsects and other terrestrial invertebrates are declining in species richness and abundance. This includes the invertebrates associated with herbivore dung, which have been negatively affected by grazing abandonment and the progressive loss of large herbivores since the Late Pleistocene. Importantly, traditional monitoring of these invertebrates is time-consuming and requires considerable taxonomic expertise, which is becoming increasingly scarce.
View Article and Find Full Text PDFEnvironmental DNA (eDNA) provides a promising supplement to traditional sampling methods for population genetic inferences, but current studies have almost entirely focused on short mitochondrial markers. Here, we develop one mitochondrial and one nuclear set of target capture probes for the whale shark (Rhincodon typus) and test them on seawater samples collected in Qatar to investigate the potential of target capture for eDNA-based population studies. The mitochondrial target capture successfully retrieved ~235× (90× - 352× per base position) coverage of the whale shark mitogenome.
View Article and Find Full Text PDFEnvironmental DNA (eDNA) extracted from water samples has recently shown potential as a valuable source of population genetic information for aquatic macroorganisms. This approach offers several potential advantages compared with conventional tissue-based methods, including the fact that eDNA sampling is noninvasive and generally more cost-efficient. Currently, eDNA approaches have been limited to single-marker studies of mitochondrial DNA (mtDNA), and the relationship between eDNA haplotype composition and true haplotype composition still needs to be thoroughly verified.
View Article and Find Full Text PDFConservation and management of marine biodiversity depends on biomonitoring of marine habitats, but current approaches are resource-intensive and require different approaches for different organisms. Environmental DNA (eDNA) extracted from water samples is an efficient and versatile approach to detecting aquatic animals. In the ocean, eDNA composition reflects local fauna at fine spatial scales, but little is known about the effectiveness of eDNA-based monitoring of marine communities at larger scales.
View Article and Find Full Text PDFOcean circulation, geological history, geographic distance, and seascape heterogeneity play an important role in phylogeography of coral-dependent fishes. Here, we investigate potential genetic population structure within the yellowbar angelfish () across the Northwestern Indian Ocean (NIO). We then discuss our results with respect to the above abiotic features in order to understand the contemporary distribution of genetic diversity of the species.
View Article and Find Full Text PDFThe relationships of crustaceans and hexapods (Pancrustacea) have been much discussed and partially elucidated following the emergence of phylogenomic data sets. However, major uncertainties still remain regarding the position of iconic taxa such as Branchiopoda, Copepoda, Remipedia, and Cephalocarida, and the sister group relationship of hexapods. We assembled the most taxon-rich phylogenomic pancrustacean data set to date and analyzed it using a variety of methodological approaches.
View Article and Find Full Text PDFSchistosomiasis is a water-based, infectious disease with high morbidity and significant economic burdens affecting >250 million people globally. Disease control has, with notable success, for decades focused on drug treatment of infected human populations, but a recent paradigm shift now entails moving from control to elimination. To achieve this ambitious goal, more sensitive diagnostic tools are needed to monitor progress toward transmission interruption in the environment, especially in low-intensity infection areas.
View Article and Find Full Text PDFTerrestrial arthropods comprise the most species-rich communities on Earth, and grassland flowers provide resources for hundreds of thousands of arthropod species. Diverse grassland ecosystems worldwide are threatened by various types of environmental change, which has led to decline in arthropod diversity. At the same time, monitoring grassland arthropod diversity is time-consuming and strictly dependent on declining taxonomic expertise.
View Article and Find Full Text PDFPopulation genetics is essential for understanding and managing marine ecosystems, but sampling remains challenging. We demonstrate that high-throughput sequencing of seawater environmental DNA can provide useful estimates of genetic diversity in a whale shark (Rhincodon typus) aggregation. We recover similar mitochondrial haplotype frequencies in seawater compared to tissue samples, reliably placing the studied aggregation in a global genetic context and expanding the applications of environmental DNA to encompass population genetics of aquatic organisms.
View Article and Find Full Text PDFFor several hundred years freshwater crayfish (Crustacea-Decapoda-Astacidea) have played an important ecological, cultural and culinary role in Scandinavia. However, many native populations of noble crayfish Astacus astacus have faced major declines during the last century, largely resulting from human assisted expansion of non-indigenous signal crayfish Pacifastacus leniusculus that carry and transmit the crayfish plague pathogen. In Denmark, also the non-indigenous narrow-clawed crayfish Astacus leptodactylus has expanded due to anthropogenic activities.
View Article and Find Full Text PDFRemote polar and deepwater fish faunas are under pressure from ongoing climate change and increasing fishing effort. However, these fish communities are difficult to monitor for logistic and financial reasons. Currently, monitoring of marine fishes largely relies on invasive techniques such as bottom trawling, and on official reporting of global catches, which can be unreliable.
View Article and Find Full Text PDFInsect responses to recent climate change are well documented, but the role of resource specialization in determining species vulnerability remains poorly understood. Uncovering local ecological effects of temperature change with high-quality, standardized data provides an important first opportunity for predictions about responses of resource specialists, and long-term time series are essential in revealing these responses. Here, we investigate temperature-related changes in local insect communities, using a sampling site with more than a quarter-million records from two decades (1992-2009) of full-season, quantitative light trapping of 1543 species of moths and beetles.
View Article and Find Full Text PDFGlobal biodiversity in freshwater and the oceans is declining at high rates. Reliable tools for assessing and monitoring aquatic biodiversity, especially for rare and secretive species, are important for efficient and timely management. Recent advances in DNA sequencing have provided a new tool for species detection from DNA present in the environment.
View Article and Find Full Text PDFPhilos Trans R Soc Lond B Biol Sci
January 2015
DNA obtained from environmental samples such as sediments, ice or water (environmental DNA, eDNA), represents an important source of information on past and present biodiversity. It has revealed an ancient forest in Greenland, extended by several thousand years the survival dates for mainland woolly mammoth in Alaska, and pushed back the dates for spruce survival in Scandinavian ice-free refugia during the last glaciation. More recently, eDNA was used to uncover the past 50 000 years of vegetation history in the Arctic, revealing massive vegetation turnover at the Pleistocene/Holocene transition, with implications for the extinction of megafauna.
View Article and Find Full Text PDFAsthma exacerbations are among the most frequent causes of hospitalization during childhood, but the underlying mechanisms are poorly understood. We performed a genome-wide association study of a specific asthma phenotype characterized by recurrent, severe exacerbations occurring between 2 and 6 years of age in a total of 1,173 cases and 2,522 controls. Cases were identified from national health registries of hospitalization, and DNA was obtained from the Danish Neonatal Screening Biobank.
View Article and Find Full Text PDFThe exploitation of non-invasive samples has been widely used in genetic monitoring of terrestrial species. In aquatic ecosystems, non-invasive samples such as feces, shed hair or skin, are less accessible. However, the use of environmental DNA (eDNA) has recently been shown to be an effective tool for genetic monitoring of species presence in freshwater ecosystems.
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