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showing 10 items of 17345 documents
Controlled feeding experiments with diets of different abrasiveness reveal slow development of mesowear signal in goats ( Capra aegagrus hircus )
2018
ABSTRACT Dental mesowear is applied as a proxy to determine the general diet of mammalian herbivores based on tooth-cusp shape and occlusal relief. Low, blunt cusps are considered typical of grazers and high, sharp cusps typical of browsers. However, how internal or external abrasives impact mesowear, and the time frame the wear signature takes to develop, still need to be explored. Four different pelleted diets of increasing abrasiveness (lucerne, grass, grass and rice husks, and grass, rice husks and sand) were fed to four groups of a total of 28 adult goats in a controlled feeding experiment over a 6-month period. Tooth morphology was captured by medical CT scans at the beginning and end…
Ocean acidification at a coastal CO2 vent induces expression of stress-related transcripts and transposable elements in the sea anemone Anemonia viri…
2019
Published version, available at: https://doi.org/10.1371/journal.pone.0210358 Ocean acidification threatens to disrupt interactions between organisms throughout marine ecosystems. The diversity of reef-building organisms decreases as seawater CO2 increases along natural gradients, yet soft-bodied animals, such as sea anemones, are often resilient. We sequenced the polyA-enriched transcriptome of adult sea anemone Anemonia viridis and its dinoflagellate symbiont sampled along a natural CO2 gradient in Italy to assess stress levels in these organisms. We found that about 1.4% of the anemone transcripts, but only ~0.5% of the Symbiodinium sp. transcripts were differentially expressed. Processe…
Climate Change Genomics Calls for Standardized Data Reporting
2020
The advent of new and affordable high-throughput sequencing techniques allows for the investigation of the genetic basis of environmental adaptation throughout the plant and animal kingdom. The framework of genotype-environment associations (GEA) provides a powerful link by correlating the geographic distribution of genotype patterns of individuals or populations with environmental factors on a spatial scale. We coarsely review the short history of GEA studies, summarizing available studies, organisms, data type, and data availability for these studies. GEA is a powerful tool in climate change research and we therefore focus on climate variables as environmental factors. While our initial a…
Marine protected areas rescue a sexually selected trait in European lobster
2020
Abstract Marine protected areas (MPAs) are increasingly implemented worldwide to maintain and restore depleted populations. However, despite our knowledge on the myriad of positive responses to protection, there are few empirical studies on the ability to conserve species’ mating patterns and secondary sexual traits. In male European lobsters (Homarus gammarus), the size of claws relative to body size correlates positively with male mating success and is presumably under sexual selection. At the same time, an intensive trap fishery exerts selection against large claws in males. MPAs could therefore be expected to resolve these conflicting selective pressures and preserve males with large cl…
An integrative identification guide to the Hydrozoa (Cnidaria) of Bocas del Toro, Panama
2018
This work is the first attempt to assess the biodiversity of the Hydrozoa in the Archipiélago de Bocas del Toro (Panamá, Caribbean Sea) using morphology and molecular taxonomy, and to produce field identification tools to help future identification and monitoring efforts in the area. We sampled, identified, vouchered, and barcoded 112 specimens of Hydrozoa from shallow coastal waters (0–22 m depth) in the Archipiélago de Bocas del Toro. The specimens belong to 70 taxa, of which 53 were identified at the species level, and 17 were identified at the genus or family level. We produced 64 sequences of the large ribosomal subunit of the mitochondrial RNA (mt lsu-rRNA, 16S), the genetic marker ge…
Northern European Salmo trutta (L.) populations are genetically divergent across geographical regions and environmental gradients
2020
The salmonid fish Brown trout is iconic as a model for the application of conservation genetics to understand and manage local interspecific variation. However, there is still scant information about relationships between local and large-scale population structure, and to what extent geographical and environmental variables are associated with barriers to gene flow. We used information from 3,782 mapped SNPs developed for the present study and conducted outlier tests and gene–environment association (GEA) analyses in order to examine drivers of population structure. Analyses comprised >2,600 fish from 72 riverine populations spanning a central part of the species' distribution in norther…
A roadmap for understanding the evolutionary significance of structural genomic variation
2020
Author's accepted manuscript Structural genomic variants (SVs) take diverse forms and are ubiquitous drivers of ecological and evolutionary processes. Most studies of SVs focus on the adaptive significance of gene duplications and large inversions. Future studies should catalog SVs of all types and sizes and systematically test their evolutionary implications. We propose a roadmap and definitions for the study of SVs in ecological and evolutionary genomics. Best practices for SV detection are needed to facilitate comparisons across studies. Integrating population genomic, theoretical, and experimental approaches to SVs will more comprehensively characterize genomic variation, uncover the ad…
Demographic history has shaped the strongly differentiated corkwing wrasse populations in Northern Europe
2019
Understanding the biological processes involved in genetic differentiation and divergence between populations within species is a pivotal aim in evolutionary biology. One particular phenomenon that requires clarification is the maintenance of genetic barriers despite the high potential for gene flow in the marine environment. Such patterns have been attributed to limited dispersal or local adaptation, and to a lesser extent to the demographic history of the species. The corkwing wrasse (Symphodus melops) is an example of a marine fish species where regions of particular strong divergence are observed. One such genetic break occurred at a surprisingly small spatial scale (FST ~0.1), over a s…
Disentangling higher trophic level interactions in the cabbage aphid food web using high-throughput DNA sequencing
2017
International audience; The lack of understanding of complex food-web interactions has been a major gap in the history of biological control. In particular, a better understanding of the functioning of pest food-webs and how they vary between native and invaded geographical ranges is of prime interest for biological control research and associated integrated pest management. Technical limitations associated with the deciphering of complex food-webs can now be largely overcome by the use of high throughput DNA sequencing techniques such as Illumina MiSeq. We tested the efficiency of this next generation sequencing technology in a metabarcoding approach, to study aphid food-webs using the cab…
Daphnia invest in sexual reproduction when its relative costs are reduced
2018
The timing of sex in facultatively sexual organisms is critical to fitness, due to the differing demographic consequences of sexual versus asexual reproduction. In addition to the costs of sex itself, an association of sex with the production of dormant life stages also influences the optimal use of sex, especially in environments where resting eggs are essential to survive unfavourable conditions. Here we document population dynamics and the occurrence of sexual reproduction in natural populations of Daphnia magna across their growing season. The frequency of sexually reproducing females and males increased with population density and with decreasing asexual clutch sizes. The frequency of…