Biogeography pattern of the marine angiosperm Cymodocea nodosa in the eastern Mediterranean Sea related to the quaternary climatic changes

Acknowledgments This research has been co-financed by the European Union (European Social Fund – ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: THALES. The authors would like to thank M. Malandrakis and A. Lolas for their contribution to sampling.Peer reviewedPublisher PD

Responses of the Mediterranean seagrass Cymodocea nodosa to combined temperature and salinity stress at the ionomic, transcriptomic, ultrastructural and photosynthetic levels

Acknowledgements We are particularly grateful to David E. Salt and John M.C. Danku (University of Aberdeen, now at the University of Nottingham) for providing facilities and guidance for the ionomics work within the framework of this study. This research was funded by the European Commission (European Social Fund – ESF; grant no. 375425) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF) - Research Funding Program: THALES - Investing in knowledge society through the European Social Funds (Project Acronym: MANTOLES). We would also like to thank the TOTAL Foundation (Project “Diversity of brown algae in the Eastern Mediterranean”), the European Commission under its Horizon 2021 Research and Innovation Programme (grants ZEROBRINE, grant agreement No. 730390, and WATERMINING, grant agreement No. 869474) and the UK Natural Environment Research Council for their Supplort to FCK (program Oceans 2025 – WP 4.5 and grants NE/D521522/1 and NE/J023094/1). The MASTS pooling initiative (Marine Alliance for Science and Technology for Scotland, funded by the Scottish Funding Council and contributing institutions; grant reference HR09011) is gratefully acknowledged.Peer reviewedPostprin

Genomics of post-bottleneck recovery in the northern elephant seal.

Populations and species are threatened by human pressure, but their fate is variable. Some depleted populations, such as that of the northern elephant seal (Mirounga angustirostris), recover rapidly even when the surviving population was small. The northern elephant seal was hunted extensively and taken by collectors between the early 1800s and 1892, suffering an extreme population bottleneck as a consequence. Recovery was rapid and now there are over 200,000 individuals. We sequenced 260 modern and 8 historical northern elephant seal nuclear genomes to assess the impact of the population bottleneck on individual northern elephant seals and to better understand their recovery. Here we show that inbreeding, an increase in the frequency of alleles compromised by lost function, and allele frequency distortion, reduced the fitness of breeding males and females, as well as the performance of adult females on foraging migrations. We provide a detailed investigation of the impact of a severe bottleneck on fitness at the genomic level and report on the role of specific gene systems. [Abstract copyright: © 2024. The Author(s).

Population genetic structure of the European hake in the Greek waters, using COI MtDNA marker

The European hake, Merluccius merluccius is a high-profile commercial species, inhabits eastern Atlantic and Mediterranean Sea. Often, species at the end of distribution are characterized by relatively low genetic diversity. This study aims to identify the genetic diversity of the M.merluccius in Greek waters and compare it with western Mediterranean and Atlantic Ocean. Six populations distributed all along the Greek waters, along with one in western Mediterranean and two in the Atlantic were analysed using the cytochrome oxidase subunit I (COI). Median-joining Network analyses revealed two distinct haplotype clusters in the Greek waters, with the north-eastern Aegean favoring a unique region-specific haplotype. FST and Bayesian inference also support the genetic differentiation of the north-eastern Aegean population, which is also considered as the edge of dispersion of the species. The present study contributed to existing knowledge of the genetic structure of M.merluccius giving a new insight in the eastern Mediterranean, and it can be useful for its future conservation

Morphology and Genetic Structure Profile of Farmed Snails <i>Cornu aspersum aspersum</i> and <i>Cornu aspersum maximum</i> in Greece

The subspecies of the species Cornu aspersum, C. a. aspersum, and C. a. maximum are the dominant farmed species in Greece. The morphological and molecular polymorphism of the two aforementioned subspecies has not been studied in depth. In this study, the polymorphism of snails of the two subspecies derived from seven snail farms throughout Greece was studied using morphological and molecular markers. Firstly, the snail samples of both subspecies were categorized in three shell patterns based on shell color and existence of bands. The conducted population structure analysis revealed three major clusters among the farmed snail populations. As concerns genetic diversity, six loci (Ha5, Ha6, Ha8, Ha9, Ha10, and Ha11) were tested for their polymorphism. Genetic variation was reported within populations rather than among populations. Finally, the obtained data highlighted a common gene pool broodstock for snail farms throughout Greece

Small Scale Fisheries, Dolphins and Societal Challenges: A Case Study in the City of Volos, Greece

Existing literature on dolphin-fisheries interaction focused on Greece reveals both an undeveloped area for research, but also a lack of relevant data in this field. Although imperative, relevant research has been slow on innovation and cooperation among universities, official bureaus, and NGOs that are obliged to work together as European and national laws dictate. Most of the research in this new field focuses on the interaction between marine mammals and local fisheries, suggesting that this relationship may be problematic for both parties since the former are being treated (at least occasionally) with brutality, while the latter try to deal with economic loss. Dolphins and fishermen operate within the same ecological niches for their survival, the main area of conflict being nutritious fish. Anthropological research on ethnic identity has long dealt with antagonistic relationships over resources between adjacent groups of people. Marine biologists’ research in Greece focuses on the human factor, and some of its shortcomings may well be seen as the result of limited, or an absence of, training in social sciences. This article attempts to draw from anthropological theory to shed light on a particular symbiosis between humans and dolphins. Multidisciplinary approaches gain ground in a wide range of research interests and seem to be fruitful in terms of theoretical and practical results

Genomics Of Habitat Choice And Adaptive Evolution In A Deep-Sea Fish

Intraspecific diversity promotes evolutionary change, and when partitioned among geographic regions or habitats can form the basis for speciation. Marine species live in an environment that can provide as much scope for diversification in the vertical as in the horizontal dimension. Understanding the relevant mechanisms will contribute significantly to our understanding of eco-evolutionary processes and effective biodiversity conservation. Here, we provide an annotated genome assembly for the deep-sea fish Coryphaenoides rupestris and re-sequencing data to show that differentiation at non-synonymous sites in functional loci distinguishes individuals living at different depths, independent of horizontal spatial distance. Our data indicate disruptive selection at these loci; however, we find no clear evidence for differentiation at neutral loci that may indicate assortative mating. We propose that individuals with distinct genotypes at relevant loci segregate by depth as they mature (supported by survey data), which may be associated with ecotype differentiation linked to distinct phenotypic requirements at different depths

First Report of the Parasitic Nematode <i>Pseudoterranova</i> spp. Found in Mediterranean Monk Seal (<i>Monachus monachus</i>) in Greece: Conservation Implications

The Mediterranean monk seal (Monachus monachus) is classified as an endangered species by the IUCN, with a global population that does not exceed 800 individuals. There is limited understanding around the biology and health status of the species, rendering possible parasitic infections grave for its conservation efforts. The aim of the current study was the molecular identification of a parasitic nematode found in the digestive system of a sub-adult Mediterranean monk seal individual, that was found stranded in the area of Pagasitikos Gulf, Greece in 2019. Analysis of the stomach contents revealed the presence of two intact female nematode individuals. Standard protocols were followed as DNA extraction of the parasites was conducted and PCR amplification of the cytochrome oxidase subunit I (COI) mitochondrial gene was implemented. Sequencing analysis of a 585 bp-amplified product displayed a 96% similarity of the screened nematodes to the Pseudoterranova bulbosa species. Bayesian inference was implemented for the subsequent tree reconstruction. The phylogenetic tree revealed a clear genetic similarity between our parasitic nematode individuals named as Pseudoterranova spp. and Pseudoterranova bulbosa (bootstrap value: 82%), which is indicated for the first and only time as such, to be found in the waters of the Mediterranean Sea and also in the stomach of a Mediterranean monk seal

First Report of the Parasitic Nematode Pseudoterranova spp. Found in Mediterranean Monk Seal (Monachus monachus) in Greece: Conservation Implications

The Mediterranean monk seal (Monachus monachus) is classified as an endangered species by the IUCN, with a global population that does not exceed 800 individuals. There is limited understanding around the biology and health status of the species, rendering possible parasitic infections grave for its conservation efforts. The aim of the current study was the molecular identification of a parasitic nematode found in the digestive system of a sub-adult Mediterranean monk seal individual, that was found stranded in the area of Pagasitikos Gulf, Greece in 2019. Analysis of the stomach contents revealed the presence of two intact female nematode individuals. Standard protocols were followed as DNA extraction of the parasites was conducted and PCR amplification of the cytochrome oxidase subunit I (COI) mitochondrial gene was implemented. Sequencing analysis of a 585 bp-amplified product displayed a 96% similarity of the screened nematodes to the Pseudoterranova bulbosa species. Bayesian inference was implemented for the subsequent tree reconstruction. The phylogenetic tree revealed a clear genetic similarity between our parasitic nematode individuals named as Pseudoterranova spp. and Pseudoterranova bulbosa (bootstrap value: 82%), which is indicated for the first and only time as such, to be found in the waters of the Mediterranean Sea and also in the stomach of a Mediterranean monk seal

Sex-specific impact of inbreeding on pathogen load in the striped dolphin

The impact of inbreeding on fitness has been widely studied and provides consequential inference about adaptive potential and the impact on survival for reduced and fragmented natural populations. Correlations between heterozygosity and fitness are common in the literature, but they rarely inform about the likely mechanisms. Here, we investigate a pathology with a clear impact on health in striped dolphin hosts (a nematode infection that compromises lung function). Dolphins varied with respect to their parasite burden of this highly pathogenic lung nematode (Skrjabinalius guevarai). Genetic diversity revealed by high-resolution restriction-associated DNA (43 018 RADseq single nucleotide polymorphisms) analyses showed a clear association between heterozygosity and pathogen load, but only for female dolphins, for which the more heterozygous individuals had lower Sk. guevarai burden. One locus identified by RADseq was a strong outlier in association with parasite load (heterozygous in all uninfected females, homozygous for 94% of infected females), found in an intron of the citron rho-interacting serine/threonine kinase locus (associated with milk production in mammals). Allelic variation at the Class II major histocompatability complex DQB locus was also assessed and found to be associated with both regional variation and with pathogen load. Both sex specificity and the identification of associating functional loci provide insight into the mechanisms by which more inbred individuals may be more susceptible to the infection of this parasite. This provides important insight towards our understanding of the impact of inbreeding in natural populations, relevant to both evolutionary and practical conservation considerations