Publications by authors named "David Eme"

Article Synopsis
  • Research on the evolution of phenotypic traits during the transition to novel environments, particularly groundwater colonization by surface organisms, is limited due to challenges in studying diverse species.
  • The team has developed the World Asellidae database (WAD), which provides extensive data on freshwater isopods, including species occurrences, specimens, and genetic information, to aid in comparative evolutionary studies.
  • Through a phylogenetic analysis involving 34 species pairs, evidence is presented that male body size decreases when transitioning to groundwater habitats, suggesting evolutionary pressures from competition for females may drive this change.
View Article and Find Full Text PDF

The global biodiversity crisis due to anthropogenic pressures jeopardizes marine ecosystem functioning and services. Community responses to these environmental changes can be assessed through functional diversity, a biodiversity component related to organism-environment interactions, and estimated through biological traits related to organism functions (locomotion, feeding mode, and reproduction). Fish play a key role in marine systems functioning and supply proteins for billions of humans worldwide, yet most of the knowledge is limited to several commercial species and little is known about the intraspecific variability of their functional traits.

View Article and Find Full Text PDF

Variation in both inter- and intraspecific traits affects community dynamics, yet we know little regarding the relative importance of external environmental filters versus internal biotic interactions that shape the functional space of communities along broad-scale environmental gradients, such as latitude, elevation, or depth. We examined changes in several key aspects of functional alpha diversity for marine fishes along depth and latitude gradients by quantifying intra- and interspecific richness, dispersion, and regularity in functional trait space. We derived eight functional traits related to food acquisition and locomotion and calculated seven complementary indices of functional diversity for 144 species of marine ray-finned fishes along large-scale depth (50-1200 m) and latitudinal gradients (29°-51° S) in New Zealand waters.

View Article and Find Full Text PDF

All organisms on Earth are exposed to low doses of natural radioactivity but some habitats are more radioactive than others. Yet, documenting the influence of natural radioactivity on the evolution of biodiversity is challenging. Here, we addressed whether organisms living in naturally more radioactive habitats accumulate more mutations across generations using 14 species of waterlice living in subterranean habitats with contrasted levels of radioactivity.

View Article and Find Full Text PDF

Five decades ago, a landmark paper in Science titled The Cave Environment heralded caves as ideal natural experimental laboratories in which to develop and address general questions in geology, ecology, biogeography, and evolutionary biology. Although the 'caves as laboratory' paradigm has since been advocated by subterranean biologists, there are few examples of studies that successfully translated their results into general principles. The contemporary era of big data, modelling tools, and revolutionary advances in genetics and (meta)genomics provides an opportunity to revisit unresolved questions and challenges, as well as examine promising new avenues of research in subterranean biology.

View Article and Find Full Text PDF

Understanding patterns and processes governing biodiversity along broad-scale environmental gradients, such as depth or latitude, requires an assessment of not just taxonomic richness, but also morphological and functional traits of organisms. Studies of traits can help to identify major selective forces acting on morphology. Currently, little is known regarding patterns of variation in the traits of fishes at broad spatial scales.

View Article and Find Full Text PDF

Ecological criteria are needed for a comprehensive evaluation of groundwater ecosystem health by including biological components with the physical and chemical properties that are already required by European directives. Two methodological approaches to assess the ecological status of groundwater ecosystems were combined in two alluvial plains (the Ariège and Hers Rivers, southwestern France) varying in agriculture intensity (from grassland to crop rotation including maize and sunflower, and to maize monoculture). In the first approach, the composition of invertebrate assemblages (only obligate-groundwater crustaceans, i.

View Article and Find Full Text PDF

The evolutionary origin of the striking genome size variations found in eukaryotes remains enigmatic. The effective size of populations, by controlling selection efficacy, is expected to be a key parameter underlying genome size evolution. However, this hypothesis has proved difficult to investigate using empirical data sets.

View Article and Find Full Text PDF

Hippidions were equids with very distinctive anatomical features. They lived in South America 2.5 million years ago (Ma) until their extinction approximately 10 000 years ago.

View Article and Find Full Text PDF