Cultivating epizoic diatoms provides insights into the evolution and ecology of both epibionts and hosts

11 pages, 3 figures, 1 table, supplementary information https://doi.org/10.1038/s41598-022-19064-0.-- Data availability: DNA sequence data generated for this study are published on the NCBI GenBank online sequence depository under the accession numbers listed in Table S1. Additional micrographs and cleaned voucher material from the sequenced cultures are available from lead author MPAOur understanding of the importance of microbiomes on large aquatic animals—such as whales, sea turtles and manatees—has advanced considerably in recent years. The latest observations indicate that epibiotic diatom communities constitute diverse, polyphyletic, and compositionally stable assemblages that include both putatively obligate epizoic and generalist species. Here, we outline a successful approach to culture putatively obligate epizoic diatoms without their hosts. That some taxa can be cultured independently from their epizoic habitat raises several questions about the nature of the interaction between these animals and their epibionts. This insight allows us to propose further applications and research avenues in this growing area of study. Analyzing the DNA sequences of these cultured strains, we found that several unique diatom taxa have evolved independently to occupy epibiotic habitats. We created a library of reference sequence data for use in metabarcoding surveys of sea turtle and manatee microbiomes that will further facilitate the use of environmental DNA for studying host specificity in epizoic diatoms and the utility of diatoms as indicators of host ecology and health. We encourage the interdisciplinary community working with marine megafauna to consider including diatom sampling and diatom analysis into their routine practicesFinancial support for sequencing and SEM comes from the Jane and the Roland Blumberg Centennial Professorship in Molecular Evolution at UT Austin and the US Department of Defense (grant number W911NF-17-2-0091). Sampling in South Africa was done with partial financial support from The Systematics Association (UK) through the Systematics Research Fund Award granted to RM (2017 and 2020). Work in the Adriatic Sea was supported by Croatian Science Foundation, project UIP-05-2017-5635 (TurtleBIOME). KF has been fully supported by the “Young researchers' career development project – training of doctoral students” of the CSF funded by the EU from the European Social Fund. NJR was funded by the Spanish government (AEI) through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe

Ancient DNA of narrow-headed vole reveal common features of the Late Pleistocene population dynamics in cold-adapted small mammals

The narrow-headed vole, collared lemming and common vole were the most abundant small mammal species across the Eurasian Late Pleistocene steppe-tundra environment. Previous ancient DNA studies of the collared lemming and common vole have revealed dynamic population histories shaped by climatic fluctuations. To investigate the extent to which species with similar adaptations share common evolutionary histories, we generated a dataset comprised the mitochondrial genomes of 139 ancient and 6 modern narrow-headed voles from several sites across Europe and northwestern Asia covering approximately the last 100 thousand years (kyr). We inferred Bayesian time-aware phylogenies using 11 radiocarbon-dated samples to calibrate the molecular clock. Divergence of the main mtDNA lineages across the three species occurred during marine isotope stages (MIS) 7 and MIS 5, suggesting a common response of species adapted to open habitat during interglacials. We identified several time-structured mtDNA lineages in European narrow-headed vole, suggesting lineage turnover. The timing of some of these turnovers was synchronous across the three species, allowing us to identify the main drivers of the Late Pleistocene dynamics of steppe- and cold-adapted species.NWOVI.C.191.070Human Origin

Influence of technological changes in “Olza” sewer interceptor on the chemical composition of Odra river and its inflows

Protection of Odra river quality against harmful mine waters is a huge challenge for science. This article treats about the influence of technological changes in the dropping system “Olza” on the chemical composition of the Odrariver waters and its inflows. The content of this article is of high importance for the environment of rivers located in the area of south -western part of Upper Silesian Coal Basin. High quality of waters is very important not only for their flora and fauna but also for people who use those waters for their daily purposes. There are eight coal mines located on the area of south-western part of Upper Silesian Coal Basin. Exploitation of hard coal deposits forces coal mines to drain their mine waters off directly to the closest rivers. The main watercourse of this area is Odra river along with its inflows river Olza and Lesnica (this one is Szotkowka’s inflow). Seeing off strongly contaminated mine waters directly to the Odra and to the rivers mentioned above caused the strong perturbations in the rivers flow. What is more it had a bad influence on their flora and fauna. Lesnica and Olza rivers were the most jeopardize ones, taking into consideration the fact that the mine waters transported from the south-west part of Upper Silesian Coal Basin were directly thrown to their waters. Strongly contaminated, mostly with chlorides and sulphates, mine waters, managed to destroy the whole rivers ecosystem. Huge chloride fluctuations were the cause of biological balance dysfunction. Most animals and plants species were destroyed. In the Olza river there was almost ten times excess of the second class degree in chlorides. In Odra river those excess were lower (only four times) just because the water managed to thin down. Taking into consideration those facts mine waters couldn’t be transported directly to the rivers. In term of 17 years, mine waters were transported through the interceptor sewer called “Olza”. System was based on the net of pipelines connecting cretin mines and their settlers with the drain line placed at the Lesnica’s river bank. The whole system belongs to the JSW Group. The brake through came after the new dropping system was activated. The system was old and needed some changes and modernizations. The old steel pipelines were replaced with new ones, made with PE and the two settlers, which belong to Moszczenica Coal Mine, were put in to the system. The new system was placed in the bottom of Odra river and was equipped with 51 nozzles settled down between two river banks. The modernization allowed to eliminate the contamination of the Lesnica and Olza rivers and prevented their flora and fauna from total distraction. It also allowed to mix the mine and the river waters just after the drop. It led to the elimination of huge chloride fluctuation in the Odra river and had a huge impact on its quality improvement. It also allowed to lower down the sulphate concentrations and what is the most important to control the magnitude of water which is transported directly to the river