Biological Bulletin最新文献

{"title":"Larvae of Deep-Sea Invertebrates Harbor Low-Diversity Bacterial Communities.","authors":"Tyler J Carrier,&nbsp;Stace E Beaulieu,&nbsp;Susan W Mills,&nbsp;Lauren S Mullineaux,&nbsp;Adam M Reitzel","doi":"10.1086/715669","DOIUrl":"https://doi.org/10.1086/715669","url":null,"abstract":"<p><p>AbstractMicrobial symbionts are a common life-history character of marine invertebrates and their developmental stages. Communities of bacteria that associate with the eggs, embryos, and larvae of coastal marine invertebrates tend to be species specific and correlate with aspects of host biology and ecology. The richness of bacteria associated with the developmental stages of coastal marine invertebrates spans four orders of magnitude, from single mutualists to thousands of unique taxa. This understanding stems predominately from the developmental stages of coastal species. If they are broadly representative of marine invertebrates, then we may expect deep-sea species to associate with bacterial communities that are similar in diversity. To test this, we used amplicon sequencing to profile the bacterial communities of invertebrate larvae from multiple taxonomic groups (annelids, molluscs, crustaceans) collected from 2500 to 3670 m in depth in near-bottom waters near hydrothermal vents in 3 different regions of the Pacific Ocean (the East Pacific Rise, the Mariana Back-Arc, and the Pescadero Basin). We find that larvae of deep-sea invertebrates associate with low-diversity bacterial communities (~30 bacterial taxa) that lack specificity between taxonomic groups. The diversity of these communities is estimated to be ~7.9 times lower than that of coastal invertebrate larvae, but this result depends on the taxonomic group. Associating with a low-diversity community may imply that deep-sea invertebrate larvae do not have a strong reliance on a microbiome and that the hypothesized lack of symbiotic contributions would differ from expectations for larvae of coastal marine invertebrates.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"241 1","pages":"65-76"},"PeriodicalIF":1.6,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/715669","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39346546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential Tolerance and Seasonal Adaptation to Temperature and Salinity Stress at a Dynamic Range Boundary Between Estuarine Gastropods.","authors":"Patrick J Krug,&nbsp;Elizabeth Shimer,&nbsp;Valerie A Rodriguez","doi":"10.1086/715845","DOIUrl":"https://doi.org/10.1086/715845","url":null,"abstract":"<p><p>AbstractInsight into how coastal organisms will respond to changing temperature and salinity regimes may be derived from studies of adaptation to fluctuating estuarine environments, especially under stressful range-edge conditions. We characterized a dynamic range boundary between two estuarine sea slugs, <i>Alderia modesta</i> (distributed across the North Pacific and North Atlantic) and <i>Alderia willowi</i>, known from southern and central California. The species overlap from Bodega Bay to San Francisco Bay, where populations are dominated by <i>A. modesta</i> after winter rains but by <i>A. willowi</i> after peak summer temperatures. Laboratory assays confirmed superior tolerance to low salinity for the northern species, <i>A. modesta</i>: encapsulated embryos developed at 8 ppt, larvae survived at 4-6 ppt, and adults survived repeated exposure to 2 ppt, salinities that reduced development or survival for the same stages of <i>A. willowi</i>. Adults did not appreciably differ in their high-temperature threshold, however. Each species showed increased tolerance to either temperature or salinity stress at its range margin, indicating plasticity or local adaptation, but at the cost of reduced tolerance to the other stressor. At its northern limit, <i>A. willowi</i> became more tolerant of low salinity during the winter rainy season, but also less heat tolerant. Conversely, <i>A. modesta</i> became more heat resistant from spring to summer at its southern limit, but less tolerant of low salinity. Trade-offs in stress tolerance may generally constrain adaptation and limit biotic response to a rapidly changing environment, as well as differentiating species niches.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"241 1","pages":"105-122"},"PeriodicalIF":1.6,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39346547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Behavioral Variability of Hatchlings Modifies Dispersal Potential in Crown Conch (<i>Melongena corona</i>): Why Do Larvae Crawl Away but Sometimes Swim?","authors":"Alexandra P Hooks,&nbsp;Scott C Burgess","doi":"10.1086/712873","DOIUrl":"https://doi.org/10.1086/712873","url":null,"abstract":"<p><p>AbstractThe diversity and consequences of development in marine invertebrates have, for a long time, provided the opportunity to understand different evolutionary solutions to living in variable environments. However, discrete classifications of development can impede a full understanding of adaptation to variable environments when behavioral, morphological, or physiological flexibility and variation exist within traditionally defined modes of development. We report here novel behavioral variability in hatchlings of a marine gastropod, the Florida crown conch (<i>Melongena corona</i>), that has broad significance for understanding the correlated evolution of development, dispersal, and reproductive strategies in variable environments. All hatchlings crawl away from egg capsules after emergence as larval pediveligers. Some subsequently swim for a brief period (seconds to minutes) before crawling again. From detailed observations of 120 individuals over 30 days, we observed 28 (23.3%) hatchlings swimming at least once (8%-50% per maternal brood). The propensity to swim was unrelated to time spent encapsulated or size at hatching and lasted for 22 days. We manipulated hypothesized environmental cues and found that the proportion of hatchlings that swam was highest in the absence of cues related to habitat or juvenile food and lowest when only habitat cues were present. The relative growth rate of hatchlings was highest when habitats contained a putative juvenile food source. About 44% of hatchlings were competent to metamorphose at emergence but did not metamorphose at this time in the lab or the field. The rate of metamorphosis increased with age and depended on the presence of unknown cues in the field. Crawl-away larvae with prolonged swimming ability may be an adaptation to balance the unpredictable risks of exclusively benthic or pelagic development and to allow the option to disperse to higher-quality habitat.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"241 1","pages":"92-104"},"PeriodicalIF":1.6,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/712873","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39347124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Signals of Positive Selection in Sea Slug Transcriptomes.","authors":"Serena Angelina Caplins","doi":"10.1086/715841","DOIUrl":"https://doi.org/10.1086/715841","url":null,"abstract":"<p><p>AbstractUnderstanding how species may respond to climate change is of paramount importance. Species that occupy highly heterogenous environments, such as intertidal zone estuarine habitats, provide an ideal test case for examining phenotypic and genomic adaptations to different environmental conditions, which may influence their response to rapidly shifting climatic conditions. The California coast is projected to experience changes in both temperature and salinity, which currently vary seasonally and latitudinally. Using comparative transcriptomics, I documented patterns of positive selection between the northern-dwelling planktotrophic sacoglossan sea slug <i>Alderia modesta</i>, which is remarkably tolerant of low temperatures and low salinities, and its southern congener <i>Alderia willowi</i>, which exhibits a striking flexibility for larval type in response to seasonally shifting changes in temperature and salinity. Out of over 4000 1-to-1 orthologous genes, I found a signal of positive selection between <i>A. willowi</i> and <i>A. modesta</i> for genes involved in cell membrane and cell transport, particularly ion homeostasis (aquaporin), cell-cell signal transduction, and phosphorylation (reduced nicotinamide adenine dinucleotide [NADH] dehydrogenase). Positive selection for ion homeostasis in <i>A. modesta</i> has implications for its ability to tolerate the lower salinity of its northern range, and in <i>A. willowi</i> substitutions in NADH may assist in the high temperature tolerance of its southern California habitats. Identifying these candidate genes enables future studies of their functionalization as we seek to understand the relationship between phenotype and genotype in species whose phenotypes are influenced by environmental conditions.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"241 1","pages":"55-64"},"PeriodicalIF":1.6,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39347125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selection Experiments in the Sea: What Can Experimental Evolution Tell Us About How Marine Life Will Respond to Climate Change?","authors":"Morgan W Kelly,&nbsp;Joanna S Griffiths","doi":"10.1086/715109","DOIUrl":"https://doi.org/10.1086/715109","url":null,"abstract":"Rapid evolution may provide a buffer against extinction risk for some species threatened by climate change; however, the capacity to evolve rapidly enough to keep pace with changing environments is unknown for most taxa. The ecosystem-level consequences of climate adaptation are likely to be the largest in marine ecosystems, where short-lived phytoplankton with large effective population sizes make up the bulk of primary production. However, there are substantial challenges to predicting climate-driven evolution in marine systems, including multiple simultaneous axes of change and considerable heterogeneity in rates of change, as well as the biphasic life cycles of many marine metazoans, which expose different life stages to disparate sources of selection. A critical tool for addressing these challenges is experimental evolution, where populations of organisms are directly exposed to controlled sources of selection to test evolutionary responses. We review the use of experimental evolution to test the capacity to adapt to climate change stressors in marine species. The application of experimental evolution in this context has grown dramatically in the past decade, shedding light on the capacity for evolution, associated trade-offs, and the genetic architecture of stress-tolerance traits. Our goal is to highlight the utility of this approach for investigating potential responses to climate change and point a way forward for future studies.","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"241 1","pages":"30-42"},"PeriodicalIF":1.6,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/715109","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39347129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptive and Plastic Responses to Environmental Variation: Introduction to a Virtual Symposium in <i>The Biological Bulletin</i>.","authors":"Patrick J Krug,&nbsp;John P Wares,&nbsp;Jonathan D Allen","doi":"10.1086/716013","DOIUrl":"https://doi.org/10.1086/716013","url":null,"abstract":"Climate change is rapidly restructuring communities and altering the distribution of biodiversity along coastlines worldwide.While many species have undergone range shifts to track their niche, other taxa may adapt to, or tolerate, the changing conditions in which they find themselves. Forecasting the biological responses of coastal systems to global change is critical, given the ecological disruption to diverse communities (Zhang et al., 2017. Proc. R. Soc. B Biol. Sci. 284: 20171772), the importance of their resources to global food security (Costello et al., 2020. Nature 588: 95–100), and the vulnerable ecosystem services provided by coastal taxa (He and Silliman, 2019. Curr. Biol. 29: R1021–R1035). However, such forecasting efforts are challenged by key differences between aquatic (marine and freshwater) and terrestrial organisms, including their life histories and physical properties of their respective environments (Pinsky et al., 2019.Nature 569: 108–111; Shlesinger andLoya, 2019. Science 365: 1002–1007). Over the past decade, researchers have built upon syntheses of prior efforts (e.g., Hoffmann and Sgro, 2011. Nature 470: 479–485; Doney et al., 2012. Annu. Rev. Mar. Sci. 4: 11–37) to better predict evolutionary responses of coastal ecosystems to climate change, leading to novel insights (Munday et al., 2013. Ecol. Lett. 12: 1488–1500; Baltar et al., 2019. Trends Ecol. Evol. 34: 1022–1033) and new research networks (e.g., https://rcn-ecs.github.io). However, challenges remain for exploring organismal and community responses to future conditions in aquatic habitats. To effectivelymodel the response of diverse organisms to changing stress regimes, we require more exploration of phenotypic diversity across environments, a","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"241 1","pages":"1-3"},"PeriodicalIF":1.6,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/716013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39347126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the Viability of American Horseshoe Crab (<i>Limulus polyphemus</i>) Embryos in Salt Marsh and Sandy Beach Habitats.","authors":"Michael R Kendrick,&nbsp;Jeff F Brunson,&nbsp;Daniel A Sasson,&nbsp;Kristin L Hamilton,&nbsp;Elizabeth L Gooding,&nbsp;Sarah L Pound,&nbsp;Peter R Kingsley-Smith","doi":"10.1086/714277","DOIUrl":"https://doi.org/10.1086/714277","url":null,"abstract":"<p><p>AbstractFor animal embryos that develop externally, the physio-chemical environment can substantially affect offspring viability. In the case of the American horseshoe crab (<i>Limulus polyphemus</i>), sediment conditions along estuarine shorelines influence development rates and embryonic viability. Sandy beach habitats are considered to have optimal conditions for horseshoe crab embryonic development; however, spawning is often observed outside of these optimal habitats, in areas such as salt marshes, where reduced oxygen availability is thought to decrease the viability of eggs laid in these sediments. We excavated horseshoe crab eggs, embryos, and trilobites laid naturally in marsh and beach sediments in South Carolina to compare their development and viability between habitats. We found all developmental stages in both marsh and beach habitats. For two of three sampling areas, trilobites were more likely to be found at beaches than at marshes. Multivariate analyses demonstrate that the prevalence of early and middle developmental stages was similar between habitats but that beaches had a greater proportion of late-stage trilobites than marshes. The lower likelihood of finding trilobites at some marshes may reflect differences in spawning phenology between habitats or reduced rates of embryonic development in marshes compared to beaches, leading to potentially different developmental timelines rather than a true reduction in viability. Nevertheless, the substantial proportions of eggs laid in salt marshes that survive to the trilobite stage indicate that spawning in this habitat could represent a previously underappreciated source of recruitment for horseshoe crab populations that may need to be incorporated into population assessments.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"240 3","pages":"145-156"},"PeriodicalIF":1.6,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/714277","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39233241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variability in Toxicity of Plastic Leachates as a Function of Weathering and Polymer Type: A Screening Study with the Copepod <i>Nitocra spinipes</i>.","authors":"Berit Gewert,&nbsp;Matthew MacLeod,&nbsp;Magnus Breitholtz","doi":"10.1086/714506","DOIUrl":"https://doi.org/10.1086/714506","url":null,"abstract":"<p><p>AbstractThe production and use of plastic over many decades has resulted in its accumulation in the world's oceans. Plastic debris poses a range of potential risks to the marine environment and its biota. Especially, the potential hazards of small plastic debris and chemicals associated with plastic have not been extensively studied. When buoyant plastic is exposed to ultraviolet radiation, it will slowly degrade and leach chemicals into surrounding waters. These leachates can include additives, sorbed organic pollutants, and degradation products of the plastic polymers. While most hazard assessments have focused on studying adverse effects due to the uptake of plastic, toxicity studies of the leachates of plastics are less common. To begin to address this knowledge gap, we studied the acute toxicity of leachates from diverse plastics in the harpacticoid copepod <i>Nitocra spinipes</i>. Our results show that leachates caused a higher toxicity after plastic was exposed to ultraviolet light compared to leaching in darkness. We observed differences in toxicity for different polymer types: polyvinyl chloride and polypropylene resulted in the most toxic leachates, while polystyrene and poly[ethylene terephthalate] were least toxic. Furthermore, we observed increased toxicity of leachates from some plastics that had been weathered in the real marine environment compared to matching new materials. Our results indicate that both weathering condition and polymer type influence the toxicity of plastic leachates.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"240 3","pages":"191-199"},"PeriodicalIF":1.6,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/714506","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39233243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of a Novel Computer-Aided System to Monitor Cardiac Activity in a Mussel Undergoing Starfish Predation.","authors":"Igor Bakhmet,&nbsp;Dmitry Ekimov","doi":"10.1086/714361","DOIUrl":"https://doi.org/10.1086/714361","url":null,"abstract":"<p><p>AbstractWe explored a modified, computer-aided monitoring system for continuous, long-term recording of Bivalvia cardiac activity. To estimate the capabilities of this system, we used it to monitor the cardiac activity of a mussel (<i>Mytilus edulis</i>) under predation threat from a starfish (<i>Asterias rubens</i>). In addition, we used a web camera to track the behavioral responses of these animals. Compared to its state during normal feeding activity, the mussel's heart rate showed no significant changes when the mussel was near the starfish. However, when the mussel was attacked by the starfish, its heart rate and contraction power (<i>i.e.</i>, amplitude) increased and subsequently decreased down to the absence of any heartbeats within 2.5 hours. The results obtained in this study proved the usefulness of this new system as a stress-monitoring tool.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"240 3","pages":"200-204"},"PeriodicalIF":1.6,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/714361","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39233242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Palatability and Physical and Chemical Defenses in Five Annelid Polychaetes from Tropical Brazilian Beaches.","authors":"Marina Cyrino Leal Coutinho,&nbsp;Valéria Laneuville Teixeira,&nbsp;Cinthya Simone Gomes Santos","doi":"10.1086/714505","DOIUrl":"https://doi.org/10.1086/714505","url":null,"abstract":"<p><p>AbstractAlthough researchers have examined numerous marine organisms' compensatory characteristics to minimize predation pressure, few have investigated the defensive mechanisms of polychaetes, despite their diversity. Thus, our study's aim was to evaluate the palatability and defensive strategies, both chemical and structural, in the polychaetes <i>Branchiomma luctuosum</i>, <i>Perinereis anderssoni</i>, <i>Phragmatopoma caudata</i>, <i>Eurythoe complanata</i>, and <i>Timarete</i> sp. Another twofold aim was to determine, by comparing our results with the literature, any latitudinal difference in the defensive strategies of <i>E. complanata</i> and to assess defensive mechanisms and palatability in relation to individuals' mobility, overtness, body regionalization, and color. Specimens were collected at Boa Viagem and Itaipu Beaches in Niterói, Rio de Janeiro, Brazil. In assays, a generalist consumer, the hermit crab <i>Calcinus tibicen</i>, was used to evaluate palatability and defenses. In palatability assays of live tissue of the polychaetes, consumers were offered a fresh piece of each polychaete to gauge their acceptance or rejection; in artificial food assays to test extracts of the polychaetes, artificial bait containing extracts of the polychaetes was offered to crabs to identify any chemical defense. Although the extracts of <i>B. luctuosum</i>, <i>E. complanata</i>, <i>P. caudata</i> (<i>i.e.</i>, opercular crown), and <i>Timarete</i> sp. were not palatable to the consumers, extracts of <i>P. anderssoni</i> and <i>P. caudata</i> (<i>i.e.</i>, body) were. Moreover, the opercular crown of <i>P. caudata</i> and the branchial crown of <i>B. luctuosum</i> showed evidence of structural and chemical defenses. The results corroborate past findings, suggesting no latitudinal variation in the defensive strategies of <i>E. complanata</i>. In general, less motile and more exposed species, aposematic or dark in color, exhibited greater investment in defensive strategies and unpalatability.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"240 3","pages":"157-168"},"PeriodicalIF":1.6,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1086/714505","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39233244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}