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Ocean acidification is a symptom of marine climate change resulting from the uptake of anthropogenic carbon dioxide (CO2) into the world's ocean, thereby potentially affecting survival, growth, and numerous other traits in fish early life stages. But some fish species are clearly more CO2-resilient than others, perhaps because they reside in more CO2-variable, inshore habitats as opposed to more CO2-stable offshore waters. Here we studied the early life CO2 sensitivity of an ecologically and economically important fish species (Black Sea Bass, Centropristis striata) that seasonally migrates between offshore overwintering and inshore feeding and nursery grounds. We produced embryos from wild spawners and reared them until 10 days post-hatch (dph) at three contrasting pCO2 levels (~400, ~2200, ~3000 µatm), finding no statistical effects of pCO2 on hatching success (~28%) or survival to 10 dph (~23%). At the extreme pCO2 level, surviving larvae were 1.2× larger and grew 55% faster compared to control pCO2 conditions. These results extend pioneering work by Meseck et al. (2022; https://doi.org/10.1002/mcf2.10200) to confirm a surprising CO2 tolerance of C. striata early life stages. This suggests existing adaptation to high CO2 conditions either because of seasonal exposures at productive inshore environments or at offshore depths during overwintering. [ABSTRACT FROM AUTHOR]

Gene regulatory divergence is thought to play an important role in adaptation, yet its extent and underlying mechanisms remain largely elusive for local adaptation with gene flow. Local adaptation is widespread in marine species despite generally high connectivity and is often associated with tightly linked genomic architectures, such as chromosomal inversions. To investigate gene regulatory evolution under gene flow and the role of inversions associated with local adaptation to a steep thermal gradient, we generated RNA-seq data from Atlantic silversides (Menidia menidia) from two locally adapted populations and their F1 hybrids, reared under two temperatures. We found substantial divergence in gene expression and thermal plasticity between populations, with up to 31% of genes being differentially expressed. Reduced thermal plasticity, temperature-dependent gene misexpression, and the disruption of coexpression networks in hybrids point toward a role of regulatory incompatibilities in local adaptation, particularly under colder temperatures. Chromosomal inversions show an accumulation of regulatory incompatibilities but are not consistently enriched for differentially expressed genes. Together, these results suggest that gene regulation can diverge substantially among populations despite gene flow, partly due to the accumulation of temperature-dependent regulatory incompatibilities within inversions. [ABSTRACT FROM AUTHOR]

Objective: The northern stock of Black Sea Bass Centropristis striata has spatially expanded over the past decade, potentially due to warming northwest Atlantic Shelf waters affecting overwintering. Methods: To gather empirical data on temperature‐dependent energetics, we quantified winter growth and lipid accumulation in juveniles from Long Island Sound using two experiments. Result: Experiment 1 measured individual length growth (GR), weight‐specific growth (SGR), growth efficiency, and lipid content at constant food levels and three static temperatures (6, 12, 19°C), resulting in decreasing GR from 0.24 mm/day at 19°C (SGR = 0.89%/day) to 0.15 mm/day at 12°C (0.54%/day) to 0.04 mm/day at 6°C (0.17%/day). Even at the coldest temperature, most juveniles sustained positive GRs and SGRs; hence, the species' true thermal growth minimum may be below 6°C. Lipid accumulation was greatest at 12°C, which is close to what overwintering juveniles likely encounter offshore. Experiment 2 measured the same traits but combined a representative thermal overwinter profile (20°C → 13°C, October–March) with seasonally varying rations designed to mimic low and high levels of food availability offshore. Monthly GR and SGR responded in the direction of seasonal food level changes. The "winter pulse" consumption average of 1.7%/feeding elicited a mean GR of 0.15 mm/day and SGR of 0.55%/day, whereas the "winter dip" consumption average of 3.8%/feeding yielded faster GR (0.20 mm/day) and SGR (0.71%/day). Growth efficiency ranged between 15% and 30% and was inversely related to food consumption. In both experiments, juveniles disproportionally accumulated lipid over lean mass, with lipid proportions tripling in experiment 2 from 4% at 65 mm to 12% at 120 mm. Conclusion: As inshore winter waters continue to warm, the energetic trade‐offs of overwinter offshore migration are likely to shift, potentially leading to a year‐round inshore Black Sea Bass presence. Impact statementBlack Sea Bass juveniles from Long Island Sound showed positive overwinter growth even at temperatures as low as 6°C. However, the best temperature for growth, survival, and lipid accumulation was 12°C, which is close to the presumed conditions at offshore overwintering habitats of this species. In addition, high food levels during winter months elicited compensatory growth. [ABSTRACT FROM AUTHOR]

Experimental studies assessing the potential impacts of ocean acidification on marine organisms have rapidly expanded and produced a wealth of empirical data over the past decade. This perspective examines four key areas of transformative developments in experimental approaches: (1) methodological advances; (2) advances in elucidating physiological and molecular mechanisms behind observed C[O.sub.2] effects; (3) recognition of short-term C[O.sub.2] variability as a likely modifier of species sensitivities (Ocean Variability Hypothesis); and (4) consensus on the multistressor nature of marine climate change where effect interactions are still challenging to anticipate. No single experiment allows predicting the fate of future populations. But sustaining the accumulation of empirical evidence is critical for more robust estimates of species reaction norms and thus for enabling better modeling approaches. Moreover, advanced experimental approaches are needed to address knowledge gaps including changes in species interactions and intraspecific variability in sensitivity and its importance for the adaptation potential of marine organisms to a high C[O.sub.2] world. Key words: Ocean Variability Hypothesis, ocean warming, acidification, oxygen decline. Les études expérimentales qui évaluent les impacts potentiels de l'acidification des océans sur les organismes marins ont rapidement pris de l'ampleur et produit une abondance de données empiriques au cours de la dernière décennie. Le présent article se penche sur quatre domaines clés d'avancées transformatives dans les approches expérimentales, à savoir : (1) les avancées méthodologiques, (2) les avancées dans l'élucidation des mécanismes physiologiques et moléculaires qui sous-tendent les effets observés du C[O.sub.2], (3) la reconnaissance de la variabilité à court terme du C[O.sub.2] comme modificateur probable de la sensibilité des espèces (hypothèse de la variabilité des océans) et (4) un consensus sur le fait que les changements climatiques marins sont source de différents facteurs de stress, de sorte qu'il demeure difficile d'anticiper les interactions d'effets. Aucune expérience ne permet à elle seule de prédire le destin de populations futures, mais il est d'importance capitale de poursuivre l'accumulation de preuves empiriques pour produire des estimations plus robustes des normes de réaction des espèces et ainsi permettre de meilleures approches de modélisation. Des approches expérimentales avancées sont en outre nécessaires pour combler des manques de connaissances notamment sur les modifications des interactions d'espèces et la variabilité intraspécifique de la sensibilité et son importance pour le potentiel d'adaptation d'organismes marins à un monde riche en C[O.sub.2]. [Traduit par la Rédaction] Mots-clés : hypothèse de la variabilité des océans, réchauffement des océans, acidification, appauvrissement en oxygène., The challenge of experimentally addressing marine climate change Anthropogenic climate change has been a scientific consensus for decades, but its reality is coming into ever sharper focus with each new [...]

Beirut’s 2015 garbage crisis provoked protests against unaccountable elites. Consociationalists consider such crises an external “load” on the system. I argue that consociation can actually cause crises by enabling elite rent-seeking. Drawing on Jessop and Poulantzas, I show that the consociational elite cartel “condenses” class interests into the Lebanese state. Concord among elites and inclusion of Gulf capital enabled rent creation through privatized garbage collection in the 1990s. This concord among rent-seeking elites made the state “agile.” In 2015, a return to consociational “immobilism” prevented effective waste-management. State and political economy must therefore be part of any assessment of consociationalism. [ABSTRACT FROM AUTHOR]

The project to decolonise the curriculum revolves around rethinking margin and centre of the discipline. To the extent that the Middle East and North Africa (MENA) is at the margin of international political economy (IPE), it is the ideal entry point to decolonise the curriculum. I conduct a summative content analysis of the six most commonly used IPE textbooks. To what extent do they reproduce or challenge Eurocentric tropes in their treatment of MENA? The region is largely absent from IPE textbooks, suggesting it is accorded little agency in the making of the global political economy. To the extent that it is 'brought in', it is 'ghettoised' in a specialist chapter. A qualitative content analysis suggests the authors avoid overt orientalism but exceptionalise the region as a failure with too little democracy and economic growth and too much war. They acknowledge the role of continued colonialism in these failures but also deny agency of the colonised. They miss an opportunity to de-provincialise the Middle East by fostering 'ecologies of knowledge'. The article provides an analytical framework for research on how IPE textbooks treat other world regions and of syllabi. [ABSTRACT FROM AUTHOR]

Human exposure to the neurotoxic methylmercury (MeHg) occurs primarily via the consumption of marine fish, but the processes underlying large-scale spatial variations in fish MeHg concentrations [MeHg], which influence human exposure, are not sufficiently understood. We used the Atlantic silverside (Menidia menidia), an extensively studied model species and important forage fish, to examine latitudinal patterns in total mercury (Hg) [Hg] and [MeHg]. Both [Hg] and [MeHg] significantly increased with latitude (0.014 and 0.048 [micro]g MeHg x g dry [weight.sup.-1] per degree of latitude in juveniles and adults, respectively). Four known latitudinal trends in silverside traits help explain these patterns: latitudinal increase in MeHg assimilation efficiency, latitudinal decrease in MeHg efflux, latitudinal increase in weight loss due to longer and more severe winters, and latitudinal increase in food consumption as an adaptation to decreasing length of the growing season. Given the absence of a latitudinal pattern in particulate MeHg, a diet proxy for zooplanktivorous fish, we conclude that large-scale spatial variation in growth is the primary control of Hg bioaccumulation in this and potentially other fish species. Si l'exposition des humains au methylmercure (MeHg), une substance neurotoxique, se produit principalement par la consommation de poissons marins, les processus qui sous-tendent les variations spatiales a grande echelle des concentrations de MeHg [MeHg] dans les poissons, qui influencent l'exposition des humains, ne sont pas assez bien compris. Nous avons utilise la capucette (Menidia menidia), une espece modele largement etudiee et un important poisson-fourrage, pour examiner la repartition spatiale du mercure (Hg) total [Hg] et de la [MeHg]. Tant la [Hg] que la [MeHg] augmentent significativement avec la latitude (0,014 et 0,048 [micro]g MeHg x g poids [sec.sup.-1] par degre de latitude chez les juveniles et les adultes, respectivement). Quatre tendances latitudinales connues de caracteres des capucettes aident a expliquer ces motifs, soit l'augmentation latitudinale de l'efficacite d'assimilation du MeHg, la diminution latitudinale de la sortie du MeHg, l'augmentation latitudinale de la perte de poids due a des hivers plus longs et rigoureux et l'augmentation latitudinale de la consommation de nourriture comme adaptation a la diminution de la periode de croissance. Etant donne l'absence de motif latitudinal du MeHg particulaire, une variable substitutive du regime alimentaire pour les poissons zooplanctonophages, nous concluons que des variations spatiales a grande echelle de la croissance constituent le principal controle de la bioaccumulation de Hg chez cette espece et, potentiellement, d'autres especes de poissons. [Traduit par la Redaction], Introduction Consumption of marine fish comprises the leading route of human exposure to methylmercury (MeHg) (Sunderland 2007), which is the toxic form of mercury (Hg) produced by microorganisms and biomagnified [...]

International political economy has largely ignored the Middle East. This special issue not only expands the discipline’s scope geographically but also conceptually by addressing IPE’s ‘blind spots’ including gender and sexuality, race and colonialism, security-economy nexus, and the expertise intensity of our economy. Contributors do so by challenging exceptionalist conceptions of the Middle Eastern states as neo-patrimonial ‘rentier states’ unable to face challenges and seize opportunities of globalization. Contributors build on openings in IPE of the Middle East by deploying historical approaches, studying logistics that facilitate flows and circulation, regarding Middle Eastern states not just as passive recipients of globalization but active makers of regional and global capitalism, and through ethnography. The purpose is not to characterize a singular ‘the Middle Eastern state’ but to contribute to novel IPE debates on the state that go beyond Eurocentric institutionalism. [ABSTRACT FROM AUTHOR]