Publications by authors named "S Arnaud-Haond"
Article Synopsis
- * The Ne/Nc ratio varies due to ecological and evolutionary factors, influencing conservation strategies, and different types of effective population sizes must be considered to grasp their implications.
- * Despite technological advancements in marine species documentation, predicting the Ne/Nc ratio remains challenging, highlighting the need for more research to effectively manage genetic diversity and population viability in these fish populations.
Article Synopsis
- Marine top predator populations, including a third of chondrichthyans, are declining, with the Mediterranean blue shark classified as critically endangered due to limited data on their population structure and connectivity.
- A genetic study on 203 blue shark specimens identified subtle genetic differences both within the Mediterranean and between it and the Northeast Atlantic, suggesting demographic independence of Western and Eastern populations.
- Despite limited reproductive interactions, the slight genetic differentiation hints at a recent shared history, indicating that Mediterranean blue sharks may act as a metapopulation influenced by local demographic changes and poor regulation of fishing practices.
Hadal sediments are hotspots of microbial activity in the deep sea and exhibit strong biogeochemical gradients. But although these gradients are widely assumed to exert selective forces on hadal microbial communities, the actual relationship between biogeochemistry, functional traits, and microbial community structure remains poorly understood. We tested whether the biogeochemical conditions in hadal sediments select for microbes based on their genomic capacity for respiration and carbohydrate utilization via a metagenomic analysis of over 153 samples from the Atacama Trench region (max.
View Article and Find Full Text PDFAmmonia-oxidizing archaea of the phylum Thaumarchaeota play a central role in the biogeochemical cycling of nitrogen in benthic sediments, at the interface between pelagic and subsurface ecosystems. However, our understanding of their niche separation and of the processes controlling their population structure in hadal and abyssal surface sediments is still limited. Here, we reconstructed 47 AOA metagenome-assembled genomes (MAGs) from surface sediments of the Atacama and Kermadec trench systems.
View Article and Find Full Text PDFThe commercially important Atlantic bluefin tuna (Thunnus thynnus), a large migratory fish, has experienced notable recovery aided by accurate resource assessment and effective fisheries management efforts. Traditionally, this species has been perceived as consisting of eastern and western populations, spawning respectively in the Mediterranean Sea and the Gulf of Mexico, with mixing occurring throughout the Atlantic. However, recent studies have challenged this assumption by revealing weak genetic differentiation and identifying a previously unknown spawning ground in the Slope Sea used by Atlantic bluefin tuna of uncertain origin.
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