Journal of Experimental Marine Biology and Ecology最新文献

{"title":"Physiological effects of acute exposure to acidification conditions in embryos of the American lobster (Homarus americanus)","authors":"A.R. Sisti ,&nbsp;B.M. Jellison ,&nbsp;J.D. Shields ,&nbsp;E.B. Rivest","doi":"10.1016/j.jembe.2025.152095","DOIUrl":"10.1016/j.jembe.2025.152095","url":null,"abstract":"<div><div>Ocean and coastal acidification are altering carbonate chemistry conditions and inducing physiological stress in marine organisms. Early life history stages of marine invertebrates, including commercially important species like the American lobster (<em>Homarus americanus</em>) may have limited physiological capacity to tolerate changes in carbonate chemistry. Using American lobster embryos, we quantified physiological disturbances caused by acute changes in carbonate chemistry. We exposed freshly isolated lobster embryos to conditions ranging from 6.94 to 8.07 pH for 24 h at three points during embryo development. With more extreme conditions of acidification, protein carbonyl concentration (indicative of cellular damage from oxidative stress) increased, and Na⁺/K⁺-ATPase activity (associated with acid-base regulation) decreased at all stages of development examined. Although oxygen consumption rate and ferric-reducing antioxidant potential both increased over the course of embryogenesis, we found no evidence that the relationship between pH and these physiological metrics varied during ontogeny. Our results indicate that acid-base regulation and oxidative stress in American lobster embryos may be sensitive to acidification-induced hypercapnia within a 24-h period across a large portion of embryo development.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"585 ","pages":"Article 152095"},"PeriodicalIF":1.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143562598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of environmental conditions on the heat tolerance of Acropora hyacinthus","authors":"Hongmin Wang ,&nbsp;He Zhao ,&nbsp;Wentao Zhu ,&nbsp;Junling Zhang ,&nbsp;Xiangbo Liu ,&nbsp;Ming Zhu ,&nbsp;Aimin Wang ,&nbsp;Xiubao Li","doi":"10.1016/j.jembe.2025.152096","DOIUrl":"10.1016/j.jembe.2025.152096","url":null,"abstract":"<div><div>While coral bleaching events are becoming increasingly frequent due to climate change, some nearshore zones exposed to high turbidity and cold-water upwelling may serve as thermal refuges to effectively mitigate the effects of heat stress. Understanding how corals in these zones adapt to environmental stressors can aid in coral management. In this study, we collected <em>Acropora hyacinthus</em> from two zones near Hainan Island: Changjiang, a nearshore coastal zone with high turbidity, and Wuzhizhou, a zone affected by the Qiongdong upwelling in the summer. The corals were subjected to heat stress in the laboratory up to 32 °C, and their responses were compared and analyzed. <em>A. hyacinthus</em> from Changjiang exhibited superior thermal tolerance, potentially due to its higher total energy reserves, consistent composition of symbiotic microbial communities (especially the photosynthetically active Symbiodiniaceae C1 and abundance of probiotic bacteria), and stability of metabolic activity. Upon heat stress, it up-regulated various metabolic pathways, including arachidonic acid metabolism, pantothenate and CoA biosynthesis, and ABC transporters, which indicated good adaptive capacity to high-temperature settings. Conversely, <em>A. hyacinthus</em> from Wuzhizhou was more vulnerable. Upon heat stress, it had a notable rise in bacterial diversity, a reduction in the abundance of probiotic bacteria, and down-regulated metabolic pathways. Thus, compared to corals in nearshore turbid zones, corals sheltered by the summer upwelling in the South China Sea east of Hainan Island are more sensitive to rising temperatures and are at a higher risk if the Qiongdong upwelling weakens due to further climate change.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"585 ","pages":"Article 152096"},"PeriodicalIF":1.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143550703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"We are where we eat! The food selectivity of Copepoda Harpacticoida species on mangrove benthic diatoms and cyanobacteria influences their spatial distribution at a microscale level","authors":"Renata Lopes Trindade ,&nbsp;Ariadne do Nascimento Moura ,&nbsp;Adriane Pereira Wandness ,&nbsp;Bruna Martins Bezerra ,&nbsp;Paulo Jorge Parreira dos Santos","doi":"10.1016/j.jembe.2025.152094","DOIUrl":"10.1016/j.jembe.2025.152094","url":null,"abstract":"<div><div>Harpacticoida participate in important benthic processes but their specific interactions with other primary producers are still unknown. This study investigated Copepoda Harpacticoida's selectivity of diatoms and cyanobacteria and whether their microscale distribution is influenced by diatoms and cyanobacteria distribution. We conducted a laboratory controlled experiment, where diatoms and cyanobacteria and four Harpacticoid species (<em>Cletocamptus</em> cf. <em>deitersi</em>, <em>Mesochra</em> sp. <em>Robertsonia mourei</em> and <em>Metis holothuriae</em>) were isolated and cultivated from water and sediment samples collected in the midlittoral zone of the Santa Cruz Canal in Pernambuco, Northeast Brazil. The grazing experiment lasted 24 h. Concurrently, sediment samples were collected with 25 contiguous syringes (1.3cm²) at one centimeter depth to verify the microspatial relation in situ. We characterized the site through the levels of chlorophyll-a, phaeopigments, silt and clay percentage, organic matter percentage and salinity. We found that the species of Copepoda Harpacticoida from a mangrove area fed selectively on different diatoms and cyanobacteria species. Furthermore, our results also indicated that there was a very low overlap in the use of diatoms and cyanobacteria by these Harpacticoida species and that the size of diatoms and cyanobacteria seemed to partially influence their selectivity. For the set of nine diatoms for which there was strong or very strong evidence that the presence of harpacticoid animals decreased their densities due to herbivore-prey interactions, seven were grazed upon by a single harpacticoid species. Our field observational study demonstrates that the aggregated spatial pattern of diatom and cyanobacteria species explains, to a large extent, the spatial distribution of Copepoda Harpacticoida species in the estuarine mud flat. For all tested species, at least one of the diatoms and cyanobacteria selected as food in the laboratory was a significant predictor of harpacticoid species spatial distribution, showing the importance of species-specific relationships.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"585 ","pages":"Article 152094"},"PeriodicalIF":1.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143521262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sponge species from New Zealand may transform and degrade dissolved organic matter","authors":"Tanja Stratmann ,&nbsp;Mario L.M. Miranda ,&nbsp;Anna de Kluijver ,&nbsp;Kathrin Busch ,&nbsp;Michelle Kelly ,&nbsp;Sadie Mills ,&nbsp;Peter J. Schupp","doi":"10.1016/j.jembe.2025.152092","DOIUrl":"10.1016/j.jembe.2025.152092","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Sponges are an important component of shallow- and deep-water ecosystems enhancing eukaryotic biodiversity via diverse endo- and epibiota and by providing three dimensional habitats for benthic invertebrates and fishes. Sponge biodiversity is particularly high in the waters around New Zealand (Southwest Pacific), where we collected two shallow- and two deep-water sponge species (&lt;em&gt;Tedania&lt;/em&gt; sp., &lt;em&gt;Suberea meandrina&lt;/em&gt;, &lt;em&gt;Farrea raoulensis&lt;/em&gt;, &lt;em&gt;Artemisina&lt;/em&gt; sp.) for &lt;em&gt;ex-situ&lt;/em&gt; incubation experiments to measure processing of dissolved organic matter (DOM). Several sponge species take up DOM and make it available to other fauna as detritus or as sponge biomass, a process known as sponge loop. However, it is unknown whether the selected sponge species are able to consume dissolved organic carbon (DOC) and/or total dissolved nitrogen (TDN).&lt;/div&gt;&lt;div&gt;We measured DOC and TDN fluxes and linked it to the bacterial communities of the sponge holobiont to address research hypothesis 1. It stated that high-microbial abundance (HMA) sponges consume more DOM than low-microbial abundance (LMA) sponges. Changes in fluorescent dissolved organic matter (FDOM) over time were investigated to address research hypothesis 2. It proposed that the fluorescence intensity F&lt;sub&gt;max&lt;/sub&gt; of fluorophores decreased in incubations that showed a significant loss in DOM. We assessed the biochemical and phospholipid-derived fatty acids (PLFAs) composition of sponge tissue to address hypothesis 3. It suggested that the PLFLA composition of sponges differs between sponge classes. Finally, we tried to better understand the role of these sponges in nutrient cycling around New Zealand by combining data from all analyses.&lt;/div&gt;&lt;div&gt;Based on the community composition of the sponge-associated bacteria, we classified &lt;em&gt;Tedania&lt;/em&gt; sp., &lt;em&gt;S. meandrina&lt;/em&gt;, and &lt;em&gt;Artemisina&lt;/em&gt; sp. as HMA sponges and &lt;em&gt;F. raoulensis&lt;/em&gt; as LMA sponge. We did not measure a significant DOC flux and only the release of TDN by &lt;em&gt;Tedania&lt;/em&gt; sp. was significantly different from 0 μmol TDN g org. C&lt;sup&gt;-1&lt;/sup&gt; d&lt;sup&gt;-1&lt;/sup&gt;. The presence of four fluorophores were detected in the FDOM pool: 2 tryptophan- and protein-like fluorophores (C1, C2), 1 humic-like fluorophore (C3), and 1 tyrosine-like fluorophore (C4). However, we could not validate hypothesis 2, because F&lt;sub&gt;max&lt;/sub&gt; of C1 decreased significantly in &lt;em&gt;S. meandrina&lt;/em&gt; incubations, whereas F&lt;sub&gt;max&lt;/sub&gt; of C2 grew in the same incubations. F&lt;sub&gt;max&lt;/sub&gt; of C3 increased in &lt;em&gt;Tedania&lt;/em&gt; sp. incubations, in which F&lt;sub&gt;max&lt;/sub&gt; of C4 decreased. In comparison, F&lt;sub&gt;max&lt;/sub&gt; of C4 in &lt;em&gt;S. meandrina&lt;/em&gt; rose. The PLFA composition of sponge tissue was dominated by long-chain fatty acids, saturated fatty acids, and monosaturated fatty acids, and most PLFAs were sponge- and bacteria-specific. We could not confirmed hypothesis 3, either, because the PLFA composition of the hexactinellid sponge i","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"585 ","pages":"Article 152092"},"PeriodicalIF":1.8,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Captive rearing reduces the sensitivity of Acartia tonsa copepods to predator cues","authors":"Eva J. Muir,&nbsp;Bradford J. Gemmell,&nbsp;Andrew M. Kramer","doi":"10.1016/j.jembe.2025.152091","DOIUrl":"10.1016/j.jembe.2025.152091","url":null,"abstract":"<div><div>Captive populations are often subject to different selective pressures than their wild counterparts, which could result in trait differences between these populations. This study investigates the effect of captive rearing on the swimming behavior and escape responses of <em>Acartia tonsa</em>, a species of marine copepod zooplankton that use hydromechanical signal detection to aid in finding food, locating mates, and avoiding predation. As captive populations of <em>A. tonsa</em> experience reduced interspecific predation and higher population densities compared to wild populations, it was hypothesized that these differences may drive adaptive evolution of swimming behavior in this species. Several components of routine swimming were compared (swimming speed, number of hops, distance of hops, frequency of hops) for groups of captive-reared and wild-caught <em>A. tonsa</em>, revealing that wild-caught copepods swim faster and hop more frequently than captive-reared copepods. However, when the escape responses of the captive-reared and wild-caught populations were compared using an artificial predator mimic, no significant differences were found in the number of sequential hops performed during the escape response, the maximum velocity of the response, or the total distance traveled during the response. Although the escape responses performed by the captive-reared and wild-caught copepods were similar, the captive-reared individuals often showed no response to the artificial predator mimic (34 % of individuals responded to the predator mimic), whereas wild individuals almost always showed a response (96 % responded). This suggests that captive rearing may have resulted in reduced sensitivity to hydromechanical signals in captive copepods compared to wild copepods, as responding to these signals in a predator-free captive environment would impose an unnecessary energy cost. This study offers new insight into how captive-rearing may impact copepod populations and provides evidence of how predator-driven evolution and density dependent selection may influence the behavior of copepod species.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"584 ","pages":"Article 152091"},"PeriodicalIF":1.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonality and hydroclimatic variability shape the functional and taxonomic diversity of nearshore fish communities in glacierized estuaries of Alaska","authors":"Lauren Sutton ,&nbsp;Brian P. Ulaski ,&nbsp;Nina C. Lundstrom ,&nbsp;Emily J. Whitney ,&nbsp;Jason B. Fellman ,&nbsp;Anne H. Beaudreau ,&nbsp;Jordan Jenckes ,&nbsp;Scott S. Gabara ,&nbsp;Brenda Konar","doi":"10.1016/j.jembe.2025.152086","DOIUrl":"10.1016/j.jembe.2025.152086","url":null,"abstract":"<div><div>Nearshore fish communities in glacierized estuaries contend with environmental changes brought on by seasons and a shifting climate, which include alterations in freshwater runoff and environmental conditions shaped by the interplay of warming temperatures and receding glaciers. Spatial and temporal changes in environmental parameters can directly impact fish behavior and community structure, thereby affecting the dynamics of the entire ecosystem. Taxonomic diversity is commonly used to measure changes in communities, and while it offers important insights into community structure, considering the functional roles of organisms is necessary for understanding community dynamics through expressed traits and trophic interactions. Here, we evaluate the influence of environmental drivers on both taxonomic and functional diversity of fish communities at multiple sites in two glacially-influenced, high-latitude regions in the Gulf of Alaska (GoA): oceanic-influenced Kachemak Bay and the more typical estuarine Lynn Canal. Sites were analyzed monthly (April–September) for three years (2019, 2021, 2022) to address two questions: (1) Do taxonomic and functional diversity of nearshore fish communities show similar patterns of interannual and regional variation in glacially-influenced GoA estuaries? and (2) Do similar seasonal (i.e., monthly) and environmental (i.e., temperature, salinity, turbidity, freshwater discharge) drivers shape taxonomic and functional fish communities within these regions? Taxonomic and functional diversity were both significantly different between the two glacially-influenced GoA regions in all years. Environmental drivers of these patterns differed, but were weak across regional comparisons. Regional taxonomic composition was correlated to temperature, salinity, and turbidity while regional functional composition was not related to any environmental variables. Within regions, seasonality played a much stronger role in structuring Lynn Canal taxonomic and functional composition compared to Kachemak Bay where a stronger interannual signature was present. Taxonomic composition in Kachemak Bay was correlated with similar environmental variables to the regional comparison while Lynn Canal taxonomic composition was correlated to salinity and discharge. Both regions exhibited weak or non-existent relationships of functional composition to environmental drivers. In the more freshwater-influenced Lynn Canal, strong taxonomic and functional coupling across months indicates that seasonality structures communities, while in the more oceanic Kachemak Bay, weak seasonal differences and strong interannual differences indicate a system more influenced by oceanographic processes, as opposed to local changes.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"584 ","pages":"Article 152086"},"PeriodicalIF":1.8,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overwintering performance of three juvenile temperate estuarine fishes","authors":"Clara Bellotto ,&nbsp;Ashley M. Fowler ,&nbsp;David J. Booth","doi":"10.1016/j.jembe.2025.152087","DOIUrl":"10.1016/j.jembe.2025.152087","url":null,"abstract":"<div><div>Estuaries, rich in biodiversity and economically valuable fish species, are increasingly threatened by climate change-induced factors that challenge fish resilience and survival. This study compared the juvenile performance of three estuarine fish species (eastern fortescue, <em>Centropogon australis</em>, common silverbiddy, <em>Gerres subfasciatus,</em> and eastern striped trumpeter, <em>Pelates sexlineatus</em>) at two water temperatures reflecting two scenarios: current Sydney winters (16 °C) and future winters under climate change (20 °C). The fishes' total range of acclimation duration was 16 days at each temperature level, and the experiment included two food levels (low and high), along with two different treatments that accounted for the orders of temperature exposure (20 °C then 16 °C, vs 16 °C then 20 °C). We used a broad range of behavioural and physiological metrics such as growth (change in mass and length), metabolic rate, bite rate, burst speed, boldness, shelter and predator escape response. Overall, as expected from metabolic theory, fish performance was generally greater at higher (future) winter temperatures than at lower (current) winter temperatures, with growth rates, change in total length, bite rate and aerobic scope higher at 20 °C than 16 °C for all species<em>. G. subfasciatus</em> and <em>P. sexlineatus</em> exhibited increased escape responses at 20 °C, with <em>P. sexlineatus</em> also showing greater boldness. Boldness was positively associated with bite rates in <em>P. sexlineatus</em>, potentially indicating foraging advantages under future warming for this species. The order of temperature treatment affected boldness for <em>G. subfasciatus</em> and growth, bite rate and burst speed for <em>P. sexlineatus</em>. Overall, and surprisingly, performance metrics were largely unrelated.</div><div>Contrary to expectations, food had no effect on fish performance either directly or interacting with temperature. Our findings suggest this study was conducted below the species' thermal optima, and future climate change may therefore favour temperate juvenile estuarine fishes at winter temperatures, with potential benefits differing among these species.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"584 ","pages":"Article 152087"},"PeriodicalIF":1.8,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The appearance of plastic debris results in impaired visually-mediated behavior in a reef fish: Evidence of visual sensory pollution","authors":"Antoine O.H.C. Leduc ,&nbsp;Mariana Santos","doi":"10.1016/j.jembe.2025.152089","DOIUrl":"10.1016/j.jembe.2025.152089","url":null,"abstract":"<div><div>Macro-plastic debris (MPD) have become ubiquitous pollutants that can negatively impact marine fauna. MPD occur in a wide range of sizes, colors and shapes. The extent to which the visual appearance of MPD can impact organisms that rely on vision is still not well understood, specifically in terms of its potential for causing distraction, masking, and misleading effects. Here, we hypothesized that, much like other disturbances caused by human activities, such as light, sound, and chemical pollution that alter environmental information and impact animal behaviors, the presence of highly visible MPD could disrupt visually-mediated behaviors by causing sensory disruption. For example, MPD that visually contrast against the seascape's background could distract a predator that uses vision to search and catch prey, which may result in mistaken prey identity and reduced hunting efficiency. Prey could also become less contrasted when their color matches that of MPD, thus masking their conspicuousness to predators. Under laboratory conditions, we tested this possibility by measuring the Sergeant major (<em>Abudefduf saxatilis</em>) damselfish's foraging efficiency to consume a set number of crustacean prey (<em>Artemias</em> spp.) in a determined period of time. This was done under each of five treatments, which consisted of a control, white MPD, green MPD and natural fragments of <em>Ulva</em> algae. We also controlled potential interference from chemicals released by MPD by having a treatment of hidden, but submerged, plastic debris. The damselfish's foraging efficiency declined significantly when exposed to white MPD. Specifically, the debris that had the highest contrast in the aquariums and most closely matched the color of <em>Artemias</em> led to the greatest negative impact on fish's foraging efficiency. The visual characteristics of these white MPD appeared to have caused sensory pollution effects, by distorting and/or masking relevant visual information, which led to impaired visually-mediated hunting behavior in this reef fish. To many marine organisms, plastic debris might appear vastly different from natural visual cues, potentially leading to unexpected consequences, which remain incompletely understood.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"584 ","pages":"Article 152089"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unravelling the secret life of MultiAnnual delayed gametophytes in the order of the Laminariales","authors":"Alexander Ebbing ,&nbsp;Scott Lindell ,&nbsp;Harald Holm ,&nbsp;Yoichi Sato ,&nbsp;Klaas Timmermans","doi":"10.1016/j.jembe.2025.152081","DOIUrl":"10.1016/j.jembe.2025.152081","url":null,"abstract":"<div><div>Research within the <em>Laminariales</em> in nature has predominantly focused on the sporophyte phase, often overlooking the other half of a bi-phasic life cycle; the gametophytes which can grow and propagate independently. This study examines the potential function that gametophytes might have within the <em>Laminariales</em>, focussing primarily on the understudied MultiAnnual Delayed (MAD) gametophyte, and comparing it with the typically researched newly formed single celled or delayed gametophyte. MAD gametophytes, characterized by extended vegetative growth before reproduction, display notable morphological and functional differences compared to their single-celled or younger multicellular counterparts. Key fundamental questions arise when discussing the evolutionary pressures that result in the formation of these older gametophytes. Why do MAD gametophytes actually exist? Why can MAD gametophytes seemingly live forever? Why do MAD gametophytes grow vegetatively and seemingly without limits? We posit an updated life cycle model for <em>Laminariales</em>, hypothesizing two phenotypically different gametophyte types, each with unique morphologies, functionalities, and reproductive behaviors. This life cycle model puts more focus on the understudied MAD gametophytes and their role in nature, thereby aiming to push for more research and thus comprehensive understanding of the in-culture selection pressures and <em>in vivo</em> life cycle dynamics that affect MAD gametophytes. An understanding that is pertinent since unravelling the secret life of MAD gametophytes is fundamental to the success of future kelp domestication and large scale rewilding efforts.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"583 ","pages":"Article 152081"},"PeriodicalIF":1.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143268336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal stress and availability of potential mates drive decisions related to thermoregulatory burrow retreat and emergence in fiddler crabs","authors":"M. Zachary Darnell,&nbsp;Asa M. Darnell","doi":"10.1016/j.jembe.2024.152076","DOIUrl":"10.1016/j.jembe.2024.152076","url":null,"abstract":"<div><div>Behavioral tradeoffs are common, as many behaviors are incompatible. In ectotherms, these tradeoffs often result from incompatibility between thermoregulatory behaviors and other critical behaviors. These trade-offs are resolved by choice, with decisions expected to be based on the costs and benefits of each behavior to optimize fitness outcomes. We examined the social and abiotic factors driving resolution of the trade-off between thermoregulatory behavior and courtship behavior in the fiddler crab <em>Austruca mjoebergi</em>. Male fiddler crabs perform a courtship display on the high intertidal sediment surface, where they face extreme thermal stress; retreat into the burrow is an effective thermoregulatory strategy but requires a cessation of courtship behavior. Surface duration decreased as environmental temperatures increased, indicating that time available for courtship is limited by high temperature. Yet when exposed to a stimulus female, males remained on the surface longer, spent less time in the burrow following a thermoregulatory retreat to the burrow, and spent an overall greater proportion of time on the sediment surface. Results demonstrate that behavioral decisions related to both burrow retreat and subsequent emergence are influenced by the abiotic and social context that determine the relative costs and benefits of the behavioral choices available to the individual.</div></div>","PeriodicalId":50197,"journal":{"name":"Journal of Experimental Marine Biology and Ecology","volume":"583 ","pages":"Article 152076"},"PeriodicalIF":1.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}