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The rise and fall of neogloboquadrina atlantica: distribution and extinction in the North Atlantic
Publication . Duque Castaño, Monica Liliana; Raymo, M.; Billups, K.; Andersen, N.; Kuhnert, H.; Voelker, Antje
Neogloboquadrina atlantica is a key North Atlantic biostratigraphic marker, characterized by pronounced coiling changes from the Late Miocene to the Early Pleistocene, yet its distribution and extinction history remain poorly constrained. Here we combine published records with new abundance counts, stratigraphic constraints, and stable isotope data from sites spanning subpolar, transitional, and subtropical settings to reconstruct the distribution, ecological preferences, and extinction history of this species across the wider North Atlantic. Our results show that the species expanded diachronously after its Late Miocene first appearance, and that the two morphotypes followed distinct trajectories through time. During the Pliocene, N. atlantica was dominated by the sinistral morphotype, whereas the dextral form became rare. The extinction histories of the two morphotypes also differed: the sinistral form shows a last occurrence near 2.4 Ma, although with regional diachroneity, whereas the dextral form displays a clearer north‐to‐south pattern, disappearing first in subpolar settings and persisting until about 1.3 Ma in the northern subtropical gyre. These phased changes occurred during a period of progressive Northern Hemisphere cooling, intensified glacial‐interglacial and millennial‐scale climate variability, and recurrent ice‐rafting, all of which likely contributed to the reorganization of suitable habitats for N. atlantica.
A single-stranded DNA virus replicates in the mitochondria of a marine oomycete
Publication . Sakuta, Kohei; Krupovic, Mart; Hejna, Ondřej; Maia, Cristiana; Jung, Marília Horta; Komatsu, Ken; Moriyama, Hiromitsu; Jung, Thomas; Botella, Leticia
A virus with a circular single-stranded DNA genome, HthCRESSV1, was discovered in an oomycete, Halophytophthora thermoambigua, isolated from brackish waters off the Algarve coast in southern Portugal. Phylogenetic analyses place this virus outside of all currently classified families within the phylum Cressdnaviricota, suggesting it represents a distinct lineage. Cellular fractionation, mitochondrial marker co-enrichment, and Southern blot analyses indicate that HthCRESSV1 is associated with mitochondria and replicates episomally. The virus is stably transmitted through zoospores and is associated with a reduced host mycelial growth. Homologous sequences corresponding to both the replication-associated protein and a membrane-associated hypothetical protein were identified in the mitochondrial genomes of several oomycete species, suggesting recurrent endogenization of HthCRESSV1-like viruses in oomycete mitochondria. Together, these findings expand the known diversity of oomycete-associated DNA viruses, identify mitochondria as an unexpected niche for DNA virus replication, and highlight marine environments as underexplored reservoirs of DNA viruses in stramenopiles.
Interactions between Laminaria ochroleuca and Mytilus sp. under copper exposure and salinity variability in IMTA systems
Publication . Cereja, Rui; Chainho, Tomás; Pereira, Alícia; Gomes, Rita V.C.; Bolotas, Daniel; Brito, Ana C.; Diniz, Mário S.; R. Costa, Pedro; Marques, António
Copper-based antifouling paints are widely used to reduce biofouling on marine and estuarine structures. Yet, copper (Cu) can be toxic to marine organisms in the surrounding environment and aquaculture systems. Such toxicity may be enhanced by salinity reduction caused by extreme weather precipitation events that are becoming more frequent under climate change-induced alterations. The present study aims to analyze the physiological effects of the salinity (34 and 25 PSU) and copper (environmentally relevant levels, 20 μg/L) interaction in an macroalgae-mussel integrated multitrophic aquaculture (IMTA) aquaculture of Laminaria ochroleuca and Mytilus sp. Growth, photosynthetic pigments, fluorescence and bioactivity were used as indicators for L. ochroleuca, while oxidative stress biomarkers and stress response biomarkers were assessed in both species. The tested Cu concentrations did not affect macroalgae growth nor Mytilus sp. condition index. The presence of Mytilus sp. enabled a reduction in Cu accumulation in macroalgae under IMTA. Salinity reduction triggered higher Cu accumulation in Mytilus sp. rather than in L. ochroleuca. Mussels exposed to Cu exhibited similar effects of whether specimens were kept under IMTA or monoculture. Salinity had no effect on macroalgae, while macroalgae exposed to Cu under monoculture conditions suffered a reduction in chl a. The presence of Mytilus sp. enabled increased L. ochroleuca photosynthetic performance with higher Fv/Fm ratios and chl a concentrations, but reduced carotene concentrations, total phenolic content and antioxidant activity. Therefore, IMTA proved to be an effective solution against Cu contamination though with a cost in macroalgae bioactivity.
Food sovereignty and agroecology in conflict zones: building resilience amidst crisis
Publication . Alum, Esther Ugo; Christine, Ainebyoona; Izah, Sylvester Chibueze; Ogwu, Matthew Chidozie; Uti, Daniel Ejim; Egwu, Chukwuoyims Kevin; Alum, Richard Obinna; Govindarajan, Rasiravathanahalli Kaveriyappan
Armed conflict disrupts agricultural production, displaces farming communities, degrades natural resources, and weakens local institutions, thereby intensifying food insecurity and dependence on humanitarian assistance. This review examined how food sovereignty and agroecology can jointly strengthen food‐system resilience, community self‐reliance, and peacebuilding in conflict‐affected settings. A qualitative narrative review was conducted using peer‐reviewed articles, institutional reports, and case studies published between 2012 and 2025 and retrieved from PubMed, Scopus, and Web of Science. Evidence was synthesized thematically around conflict‐related food‐system disruption, local control of food resources, agroecological practices, implementation barriers, and recovery strategies. Findings from Colombia, Palestine, Syria, and Somalia indicate that community‐led agroecology, including crop diversification, seed saving, agroforestry, water conservation, organic soil management, and local market development, can improve food availability, restore ecological functions, preserve traditional knowledge, strengthen livelihoods, and rebuild social cohesion. However, insecurity, displacement, contested land tenure, weak governance, inadequate financing, damaged infrastructure, and limited technical capacity constrain implementation and scale‐up. The review concludes that integrating food sovereignty with agroecology offers a context‐sensitive pathway for addressing immediate food needs while supporting long‐term ecological recovery, economic autonomy, and conflict‐sensitive development. Governments, humanitarian agencies, and development partners should embed agroecology in post‐conflict recovery policies, secure equitable land and resource rights, strengthen farmer cooperatives and extension systems, finance locally led initiatives, rebuild markets and rural infrastructure, and establish participatory monitoring frameworks that prioritize women, displaced people, indigenous groups, and smallholder farmers across affected regions.
Cyclonic surface circulation in the northern coast of the Gulf of Cádiz: insights from Lagrangian drifters and high-resolution models
Publication . Luján-Amoraga, Esther; Román-Cascón, Carlos; Jiménez Rincón, Juan Alberto; Izquierdo, Alfredo; Bruno, Miguel; Vázquez, Águeda; Relvas, Paulo; Garel, Erwan; Bolado-Penagos, Marina
This study presents direct in situ observational evidence of a cyclonic circulation cell east of Cape Santa María (CSM), in the northern Gulf of Cádiz (GoC). Three Lagrangian drifters deployed in October 2022 revealed a coherent cyclonic circulation cell with a characteristic diameter of approximately 40-45 km, consistently estimated from drifter trajectories and relative vorticity. Their trajectories showed alternating eastward and westward flows, modulated by wind variability, bathymetry, and mesoscale dynamics. Satellite observations showed a cooler, chlorophyll-a enriched core, consistent with upwelling and retention of enriched surface water masses within the circulation cell.
High-resolution WRF atmospheric simulations indicated alternating easterly and westerly wind regimes that were associated with reversals in coastal circulation. Westerly winds between 18th and 24th October produced positive Ekman pumping east of CSM, creating conditions favourable to the intensification of cyclonic circulation. The IBI ocean model reproduced the main structure of the circulation cell structure, including flow accelerations near the shelf edge, and indicated upward vertical motions within the cyclonic circulation cell.
A Lagrangian particle experiment suggested that the cyclonic cell favours both retention and offshore export of surface waters, with residence times of up to approximately 16 days. Overall, this study highlights the role of interactions between atmospheric forcing, bathymetry, and mesoscale dynamics in controlling small-scale surface circulation in the GoC, and underscores the value of integrating drifter observations, satellite data, and numerical models to characterize coastal dynamics.