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Floating life (obligate neuston) is a core component of the ocean surface food web. However, only 1 region of high neustonic abundance is known so far, the Sargasso Sea in the Subtropical North Atlantic gyre, where floating life provides critical habitat structure and ecosystem services. Here, we hypothesize that floating life is also concentrated in other gyres with converging surface currents. To test this hypothesis, we collected samples through the eastern North Pacific Subtropical Gyre in the area of the North Pacific "Garbage Patch" (NPGP) known to accumulate floating anthropogenic debris. We found that densities of floating life were higher inside the central NPGP than on its periphery and that there was a positive relationship between neuston abundance and plastic abundance for 3 out of 5 neuston taxa, Velella, Porpita, and Janthina. This work has implications for the ecology of subtropical oceanic gyre ecosystems.
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Resíduos de Alimentos , Hidrozoários , Animais , Ecossistema , Plásticos , Monitoramento Ambiental , Ecologia , Oceano PacíficoRESUMO
Life on the ocean's surface connects worlds. From shallow waters to the deep sea, the open ocean to rivers and lakes, numerous terrestrial and marine species depend on the surface ecosystem and the organisms found therein. Organisms that live freely at the surface, termed "neuston," include keystone organisms like the golden seaweed Sargassum that makes up the Sargasso Sea, floating barnacles, snails, nudibranchs, and cnidarians. Many ecologically and economically important fish species live as or rely upon neuston. Species at the surface are not distributed uniformly; the ocean's surface harbors unique neustonic communities and ecoregions found at only certain latitudes and only in specific ocean basins. But the surface is also on the front line of climate change and pollution. Despite the diversity and importance of the ocean's surface in connecting disparate habitats, and the risks it faces, we know very little about neustonic life. This Essay will introduce you to the neuston, their connections to diverse habitats, the threats they face, and new opportunities for research and discovery at the air-sea interface.
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Biodiversidade , Ecossistema , Oceanos e Mares , Animais , Mudança Climática , Poluição Ambiental , Cadeia Alimentar , Oceanos e Mares/epidemiologia , Água do MarRESUMO
OBJECTIVE: A mock jury experiment tested the effects of attorney guidance and jury deliberation to mitigate the challenges that civil juries face in assessing damages. HYPOTHESES: We hypothesized that two types of attorney guidance (per diem, per diem + lump sum), theoretically based in the Hans-Reyna model of jury decision making, would improve jury decision making compared with no guidance against five key benchmarks: injury assessment, validity, reliability, verbatim-gist coherence, and metacognitive experience. We expected that deliberation would increase reliability of, confidence in, and polarization of awards compared with predeliberation. METHOD: Community members (N = 317; 61% women; 86.1% White; Mage = 48.68 years) deliberated in 54 mock juries. Participants watched a videotaped trial involving an automobile accident in which two plaintiffs sustained concussions (one mild and one severe). The plaintiffs' attorney's closing arguments varied attorney guidance (no guidance, per diem, per diem + lump sum). Mock jurors provided individual judgments before deliberating as a jury and reaching group verdicts and awards. RESULTS: Juries performed well against benchmarks. Providing gist-based guidance with a meaningful award recommendation increased the validity of jurors' individual damage awards (η²p jurors = .03) and the reliability of jury damage awards (η²p jurors = .04; η²p jurors = .20); gist-based guidance without an award recommendation did not improve performance against benchmarks and increased perceptions of decision-making difficulty (η²p = .13). Deliberation increased reliability of (η²p = .17), confidence in (η²p = .02), and polarization of (d = 2.14) awards compared with predeliberation. CONCLUSION: Juries performed well against objective benchmarks of performance (injury assessment, validity, reliability, and verbatim-gist coherence), and deliberation improved performance compared with predeliberation decisions. Jury decisions were further influenced by attorney closing arguments (the guidance manipulation), especially when the attorney requests a lump sum, which can serve as a powerful influence on jury awards, mainly by setting an upper limit. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Tomada de Decisões , Advogados , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Reprodutibilidade dos Testes , Direito Penal , JulgamentoRESUMO
OBJECTIVES: To date, most research on plea bargaining has used some form of the shadow of the trial (SOT) model to frame defendant decisions. In this research, we proposed and tested a new conceptual model of plea decision-making, based on fuzzy-trace theory (FTT), for the context in which a nondetained, guilty defendant chooses between a guilty plea or trial, where both the plea and potential trial sentence entail incarceration. HYPOTHESES: We predicted that plea decisions would be affected by (a) meaningful, categorical changes in conviction probability (e.g., low to moderate, moderate to high), as opposed to more granular changes within categories and (b) the presence and magnitude of categorical distinctions between plea offer and potential trial sentence rather than fine-grained differences between individual offers. METHOD: We conducted three vignette-based experiments (Study 1: N = 1,701, Study 2: N = 1,098, Study 3: N = 1,232), using Mechanical Turk participants. In Studies 1 and 2, we manipulated potential trial sentence and conviction probability, asking participants to indicate either the maximum plea sentence they would accept (Study 1) or whether they would plead guilty to a specific offer (Study 2). In Study 3, we manipulated plea discount and potential trial sentence and measured plea acceptance. RESULTS: Maximum acceptable plea sentences were similar within and different between "groupings" of meaningfully similar conviction probabilities (Study 1). Plea rates were similar within and different between groupings that comprised plea offers of similarly meaningful distance from the potential trial sentence (Study 3). The results also provide insight into the plea rates that might be expected under different combinations of the independent variables (Studies 2 and 3). CONCLUSIONS: These results support a new conceptual model of plea decision-making that may be better suited to explaining case-level differences in plea outcomes than the SOT model and suggest that future research extending this model to a wider range of contexts would be fruitful. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Tomada de Decisões , Negociação , Humanos , CulpaRESUMO
Considerable advances in chronobiology have been made through controlled laboratory studies, but distinct temporal rhythms can emerge under natural environmental conditions. Lab-reared Nematostella vectensis sea anemones exhibit circadian behavioral and physiological rhythms. Given that these anemones inhabit shallow estuarine environments subject to tidal inputs, it was unclear whether circadian rhythmicity would persist following entrainment in natural conditions, or whether circatidal periodicity would predominate. Nematostella were conditioned within a marsh environment, where they experienced strong daily temperature cycles as well as brief tidal flooding around the full and new moons. Upon retrieval, anemones exhibited strong circadian (â¼24â h) activity rhythms under a light-dark cycle or continuous darkness, but reduced circadian rhythmicity under continuous light. However, some individuals in each light condition showed circadian rhythmicity, and a few individuals showed circatidal rhythmicity. Consistent with the behavioral studies, a large number of transcripts (1640) exhibited diurnal rhythmicity compared with very few (64) with semidiurnal rhythmicity. Diurnal transcripts included core circadian regulators, and 101 of 434 (23%) genes that were previously found to be upregulated by exposure to ultraviolet radiation. Together, these behavioral and transcriptional studies show that circadian rhythmicity predominates and suggest that solar radiation drives physiological cycles in this sediment-dwelling subtidal animal.
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Ritmo Circadiano/fisiologia , Fotoperíodo , Anêmonas-do-Mar/fisiologia , Animais , Animais de Laboratório/fisiologia , Escuridão , LuzRESUMO
Peroxiredoxins (PRXs) are a family of antioxidant enzymes present in all domains of life. To date, the diversity and function of peroxiredoxins within animals have only been studied in a few model species. Thus, we sought to characterize peroxiredoxin diversity in cnidarians and to gain insight into their function in one cnidarian-the sea anemone Nematostella vectensis. Phylogenetic analysis using all six known PRX subfamilies (PRX1-4, PRX5, PRX6, PRXQ/AHPE1, TPX, BCP-PRXQ) revealed that like bilaterians, cnidarians contain representatives from three subfamilies (PRX1-4, PRX5, PRX6). Within the PRX1-4 subfamily, cnidarian sequences fall into two clades: PRX4, and a cnidarian-specific clade, which we term CNID-PRX. This phylogenetic analysis demonstrates that the three PRX subfamilies present in Bilateria were also present in the last common ancestor of the Cnidaria and Bilateria, and further that diversification of the PRX1-4 subfamily has occurred within the cnidarian lineage. We next examined the impact of decreased salinity, increased temperature, and peroxide exposure on the expression of four prx genes in N. vectensis (cnid-prx, prx4, prx5, and prx6). These genes exhibited unique expression patterns in response to these environmental stressors. Expression of prx4 decreased with initial exposure to elevated temperature, cnid-prx increased with exposure to elevated temperatures as well as with hydrogen peroxide exposure, and expression of all prxs transiently decreased with reduced salinity. Predicted subcellular localization patterns also varied among PRX proteins. Together these results provide evidence that peroxiredoxins in N. vectensis serve distinct physiological roles and lay a groundwork for understanding how peroxiredoxins mediate cnidarian developmental processes and environmental responses.
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Estuários , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Peroxirredoxinas/classificação , Filogenia , Anêmonas-do-Mar/enzimologia , Estresse Fisiológico/genética , Animais , Antioxidantes/metabolismo , Evolução Molecular , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Peroxirredoxinas/química , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Conformação Proteica , Espécies Reativas de Oxigênio/metabolismo , Estresse Salino , Anêmonas-do-Mar/genética , Anêmonas-do-Mar/metabolismo , Anêmonas-do-Mar/fisiologia , Frações Subcelulares/enzimologia , TemperaturaRESUMO
Legal systems often require the translation of qualitative assessments into quantitative judgments, yet the qualitative-to-quantitative conversion is a challenging, understudied process. We conducted an experimental test of predictions from a new theory of juror damage award decision making, examining how 154 lay people engaged in the translation process in recommending money damages for pain and suffering in a personal injury tort case. The experiment varied the presence, size, and meaningfulness of an anchor number to determine how these factors influenced monetary award judgments, perceived difficulty, and subjective meaningfulness of awards. As predicted, variability in awards was high, with awards participants considered to be "medium" (rather than "low" or "high") having the most dispersion. The gist of awards as low, medium, or high fully mediated the relationship between perceived pain/suffering and award amount. Moreover, controlling for participants' perceptions of plaintiffs and defendants, as well as their desire to punish and to take economic losses into account, meaningful anchors predicted unique variance in award judgments: A meaningful large anchor number drove awards up and a meaningful small anchor drove them down, whereas meaningless large and small anchors did not differ significantly. Numeracy did not predict award magnitudes or variability, but surprisingly, more numerate participants reported that it was more difficult to pick an exact figure to compensate the plaintiff for pain and suffering. The results support predictions of the theory about qualitative gist and meaningful anchors, and suggest that we can assist jurors to arrive at damage awards by providing meaningful numbers. (PsycINFO Database Record
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Compensação e Reparação/legislação & jurisprudência , Tomada de Decisões , Feminino , Humanos , Masculino , Modelos Estatísticos , Adulto JovemRESUMO
In the American criminal justice system the vast majority of criminal convictions occur as the result of guilty pleas, often made as a result of plea bargains, rather than jury trials. The incentives offered in exchange for guilty pleas mean that both innocent and guilty defendants plead guilty. We investigate the role of attorneys in this context, through interviews with criminal defense attorneys. We examine defense attorney perspectives on the extent to which innocent defendants are (and should be) pleading guilty in the current legal framework and their views of their own role in this complex system. We also use a hypothetical case to probe the ways in which defense attorneys consider guilt or innocence when providing advice on pleas. Results indicate that attorney advice is influenced by guilt or innocence, but also that attorneys are limited in the extent to which they can negotiate justice for their clients in a system in which uncertainty and large discrepancies between outcomes of guilty pleas and conviction at trial can make it a sensible option to plead guilty even when innocent. Results also suggest conflicting opinions over the role of the attorney in the plea-bargaining process.
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Eyewitness identification has been shown to be fallible and prone to false memory. In this study we develop and test a new method to probe the mechanisms involved in the formation of false memories in this area, and determine whether a particular memory is likely to be true or false. We created a seven-step procedure based on the Implicit Association Test to gauge implicit biases in eyewitness identification (the IATe). We show that identification errors may result from unconscious bias caused by implicit associations evoked by a given face. We also show that implicit associations between negative attributions such as guilt and eyewitnesses' final pick from a line-up can help to distinguish between true and false memory (especially where the witness has been subject to the suggestive nature of a prior blank line-up). Specifically, the more a witness implicitly associates an individual face with a particular crime, the more likely it is that a memory they have for that person committing the crime is false. These findings are consistent with existing findings in the memory and neuroscience literature showing that false memories can be caused by implicit associations that are outside conscious awareness. Copyright © 2017 John Wiley & Sons, Ltd.
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Associação , Crime , Memória , Adolescente , Feminino , Culpa , Humanos , Masculino , Rememoração Mental , Adulto JovemRESUMO
Innovation is a key to evolutionary success and entrance into novel ecosystems.1 Species that float freely at the ocean's surface, termed obligate neuston (also called pleuston, here referred to simply as neuston), include highly specialized taxa from distinct evolutionary lineages that evolved floating morphologies.2 In 1958, Soviet scientist, A.I. Savilov,3 stated that floating animal species are derived from benthic ancestors, rather than species from the adjacent pelagic zone, and that floating morphologies are homologous to benthic attachment structures. To test Savilov's hypothesis, we constructed molecular phylogenies and ancestral states for all major floating groups for which molecular data were available. Our results reveal that four of the five clades examined arose directly from a substrate-attached ancestor, although that substrate was not necessarily the benthos, as Savilov stated, and instead included epibiotic and rafting ancestors. Despite their diverse evolutionary origins, floating animals use gas-trapping mechanisms to remain at the surface,4,5,6 and many of these gas-trapping structures appear to be homologous to substrate attachment structures. We also reconstruct the trophic habits of floating mollusks and their sister species, revealing that prey preference remains conserved upon entering the ocean's surface ecosystem. Colonization of the ocean's surface seems to have occurred through successive evolutionary steps from the seafloor. Our results suggest that these steps often included transitions through epibiotic (where species attach to other living organisms) or rafting (where species attach to floating debris) habits. The water-air interface, despite its unique properties, may, in some ways, be just another substrate.
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Ecossistema , Hábitos , Animais , Água , Oceanos e MaresRESUMO
BACKGROUND: Nematostella vectensis, a burrowing sea anemone, has become a popular species for the study of cnidarian development. In previous studies, the expression of a variety of genes has been characterized during N. vectensis development with in situ mRNA hybridization. This has provided detailed spatial resolution and a qualitative perspective on changes in expression. However, little is known about broad transcriptome-level patterns of gene expression through time. Here we examine the expression of N. vectensis genes through the course of development with quantitative RNA-seq. We provide an overview of changes in the transcriptome through development, and examine the maternal to zygotic transition, which has been difficult to investigate with other tools. RESULTS: We measured transcript abundance in N. vectensis with RNA-seq at six time points in development: zygote (2 hours post fertilization (HPF)), early blastula (7 HPF), mid-blastula (12 HPF), gastrula (24 HPF), planula (5 days post fertilization (DPF)) and young polyp (10 DPF). The major wave of zygotic expression appears between 7-12 HPF, though some changes occur between 2-7 HPF. The most dynamic changes in transcript abundance occur between the late blastula and early gastrula stages. More transcripts are upregulated between the gastrula and planula than downregulated, and a comparatively lower number of transcripts significantly change between planula and polyp. Within the maternal to zygotic transition, we identified a subset of maternal factors that decrease early in development, and likely play a role in suppressing zygotic gene expression. Among the first genes to be expressed zygotically are genes whose proteins may be involved in the degradation of maternal RNA. CONCLUSIONS: The approach presented here is highly complementary to prior studies on spatial patterns of gene expression, as it provides a quantitative perspective on a broad set of genes through time but lacks spatial resolution. In addition to addressing the problems identified above, our work provides an annotated matrix that other investigators can use to examine genes and developmental events that we do not examine in detail here.
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Anêmonas-do-Mar/crescimento & desenvolvimento , Anêmonas-do-Mar/genética , Animais , Gastrulação/genética , Mães , Estabilidade de RNA/genética , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência , Fatores de Tempo , Transcrição Gênica , Zigoto/metabolismoRESUMO
The open ocean beyond national jurisdiction covers nearly half of Earth's surface and is largely unexplored. It is also an emerging frontier for new types of human activity. Understanding how new activities interact with high seas ecosystems is critical for our management of this other half of Earth. Using The Ocean Cleanup (TOC) as a model, we demonstrate why it is important to account for uncertainty when assessing and evaluating impacts of novel high seas activities on marine ecosystems. TOC's aim is to remove plastic from the ocean surface by collecting it with large nets. However, this approach also results in the collection of surface marine life (neuston) as by-catch. Using an interdisciplinary approach, we explore the social-ecological implications of this activity. We use population models to quantify potential impacts on the surface ecosystem; we determine the links between these ecosystems and society through an ecosystem services approach; and we review the governance setting relevant to the management of activities on the high seas. We show that the impact of ocean surface plastic removal largely depends on neuston life histories, and ranges from potentially mild to severe. We identify broader social-ecological implications that could be felt by stakeholders both beyond and within national jurisdiction. The legal framework applicable to TOC's activities is insufficiently specific to address both the ecological and social uncertainty we describe, demonstrating the urgent need for detailed rules and procedures on environmental impact assessment and strategic environmental assessment to be adopted under the new International Agreement on the conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction which is currently being negotiated.
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Conservação dos Recursos Naturais , Ecossistema , Humanos , Biodiversidade , Atividades Humanas , Oceanos e MaresRESUMO
The low prevalence effect is a phenomenon whereby target prevalence affects performance in visual search (e.g., baggage screening) and comparison (e.g., fingerprint examination) tasks, such that people more often fail to detect infrequent target stimuli. For example, when exposed to higher base-rates of 'matching' (i.e., from the same person) than 'non-matching' (i.e., from different people) fingerprint pairs, people more often misjudge 'non-matching' pairs as 'matches'-an error that can falsely implicate an innocent person for a crime they did not commit. In this paper, we investigated whether forensic science training may mitigate the low prevalence effect in fingerprint comparison. Forensic science trainees (n = 111) and untrained novices (n = 114) judged 100 fingerprint pairs as 'matches' or 'non-matches' where the matching pair occurrence was either high (90%) or equal (50%). Some participants were also asked to use a novel feature-comparison strategy as a potential attenuation technique for the low prevalence effect. Regardless of strategy, both trainees and novices were susceptible to the effect, such that they more often misjudged non-matching pairs as matches when non-matches were rare. These results support the robust nature of the low prevalence effect in visual comparison and have important applied implications for forensic decision-making in the criminal justice system.
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Crime , Ciências Forenses , Medicina Legal , Humanos , PrevalênciaRESUMO
Eyewitness evidence is often important in criminal cases, but false or misleading eyewitness evidence is known to be a leading cause of wrongful convictions. One explanation for mistakes that jurors are making when evaluating eyewitness evidence is their lack of accurate knowledge relating to false memory. This article examines lay beliefs relating to memory and ways in which they diverge from expert consensus. It identifies ways in which current directions provided to jurors in this area are likely to be deficient in influencing juror knowledge and in helping them apply that knowledge in a case context, and develops criteria that can be used to assess the likely effectiveness of directions. A new evidence-based training direction is designed based on these criteria, and tested in a mock jury study (N = 411). Results suggest that the proposed direction is more effective than a basic direction in influencing juror knowledge and facilitating the application of that knowledge to case facts.
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Scyphozoan jellyfish, or scyphomedusae, are conspicuous members of many ocean ecosystems, and have large impacts on human health and industry. Most scyphomedusae are the final stage in a complex life cycle that also includes two intermediate stages: the larval planula and benthic polyp. In species with all three life-cycle stages, the metamorphosis of a polyp into a juvenile scyphomedusa (ephyra) is termed strobilation, and polyps can produce one ephyra (termed monodisc strobilation) or many ephyrae (termed polydisc strobilation). In contrast to species with planula, polyp and medusa stages, a handful of scyphozoan species possess modified life cycles with reduced or absent stages. The evolutionary patterns associated with strobilation and life-cycle type have not been thoroughly investigated, and many studies of ephyra development and strobilation induction are not yet synthesized. Herein, I place the development of scyphomedusae in an evolutionary context. I first review the current evolutionary hypotheses for Scyphozoa. Next, I review what is known about scyphomedusa development across a broad diversity of species, including the first signs of strobilation, the formation of strobila segments, and the morphogenesis of ephyrae. I then review cases where the canonical scyphozoan life cycle has been modified, and take advantage of phylogenetic hypotheses to place these observations in an evolutionary context. I show that the evolution of monodisc strobilation occurred at least twice, and that the loss of intermediate life-cycle stages occurred several times independently; by contrast, the reduction of the medusa stage appears to have occurred within a single clade. I then briefly review the major natural cues of strobilation induction. Finally, I summarize what is currently known about the molecular mechanisms of strobilation induction and ephyra development. I conclude with suggestions for future directions in the field.
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Estágios do Ciclo de Vida , Metamorfose Biológica/fisiologia , Filogenia , Cifozoários/genética , Cifozoários/fisiologia , AnimaisRESUMO
Criminal behavior has been associated with abnormal neural activity when people experience risks and rewards or exercise inhibition. However, neural substrates of mental representations that underlie criminal and noncriminal risk-taking in adulthood have received scant attention. We take a new approach, applying fuzzy-trace theory, to examine neural substrates of risk preferences and criminality. We extend ideas about gist (simple meaning) and verbatim (precise risk-reward tradeoffs) representations used to explain adolescent risk-taking to uncover neural correlates of developmentally inappropriate adult risk-taking. We tested predictions using a risky-choice framing task completed in the MRI scanner, and examined neural covariation with self-reported criminal and noncriminal risk-taking. As predicted, risk-taking was correlated with a behavioral pattern of risk preferences called "reverse framing" (preferring sure losses over a risky option and a risky option over sure gains, the opposite of typical framing biases) that has been linked to risky behavior in adolescents and is rarely observed in nondisordered adults. Experimental manipulations confirmed processing interpretations of typical framing (gist-based) and reverse-framing (verbatim-based) risk preferences. In the brain, covariation with criminal and noncriminal risk-taking was observed predominantly when subjects made reverse-framing choices. Noncriminal risk-taking behavior was associated with emotional reactivity (amygdala) and reward motivation (striatal) areas, whereas criminal behavior was associated with greater activation in temporal and parietal cortices, their junction, and insula. When subjects made more developmentally typical framing choices, reflecting nonpreferred gist processing, activation in dorsolateral prefrontal cortex covaried with criminal risk-taking, which may reflect cognitive effort to process gist while inhibiting preferred verbatim processing. (PsycINFO Database Record
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Encéfalo/diagnóstico por imagem , Comportamento Criminoso , Motivação , Assunção de Riscos , Adolescente , Adulto , Mapeamento Encefálico , Comportamento de Escolha/fisiologia , Feminino , Humanos , Inibição Psicológica , Imageamento por Ressonância Magnética , Masculino , Recompensa , Adulto JovemRESUMO
Many animals go through one or more metamorphoses during their lives, however, the molecular underpinnings of metamorphosis across diverse species are not well understood. Medusozoa (Cnidaria) is a clade of animals with complex life cycles, these life cycles can include a polyp stage that metamorphoses into a medusa (jellyfish). Medusae are produced through a variety of different developmental mechanisms-in some species polyps bud medusae (Hydrozoa), in others medusae are formed through polyp fission (Scyphozoa), while in others medusae are formed through direct transformation of the polyp (Cubozoa). To better understand the molecular mechanisms that may coordinate these different forms of metamorphosis, we tested two compounds first identified to induce metamorphosis in the moon jellyfish Aurelia aurita (indomethacin and 5-methoxy-2-methylindole) on a broad diversity of medusozoan polyps. We discovered that indole-containing compounds trigger metamorphosis across a broad diversity of species. All tested discomedusan polyps metamorphosed in the presence of both compounds, including species representatives of several major lineages within the clade (Pelagiidae, Cyaneidae, both clades of Rhizostomeae). In a cubozoan, low levels of 5-methoxy-2-methylindole reliably induced complete and healthy metamorphosis. In contrast, neither compound induced medusa metamorphosis in a coronate scyphozoan, or medusa production in either hydrozoan tested. Our results support the hypothesis that metamorphosis is mediated by a conserved induction pathway within discomedusan scyphozoans, and possibly cubozoans. However, failure of these compounds to induce metamorphosis in a coronate suggests this induction mechanism may have been lost in this clade, or is convergent between Scyphozoa and Cubozoa.
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Indóis/farmacologia , Metamorfose Biológica/efeitos dos fármacos , Cifozoários/crescimento & desenvolvimento , Animais , Especificidade da EspécieRESUMO
Organisms that have evolved alternative modes of reproduction, complementary to the sexual mode, are found across metazoans. The chordate Botryllus schlosseri is an emerging model for asexual development studies. Botryllus can rebuild its entire body from a portion of adult epithelia in a continuous and stereotyped process called blastogenesis. Anatomy and ontogenies of blastogenesis are well described, however molecular signatures triggering this developmental process are entirely unknown. We isolated tissues at the site of blastogenesis onset and from the same epithelia where this process is never triggered. We linearly amplified an ultra-low amount of mRNA (<10ng) and generated three transcriptome datasets. To provide a conservative landscape of transcripts differentially expressed between blastogenic vs. non-blastogenic epithelia we compared three different mapping and analysis strategies with a de novo assembled transcriptome and partially assembled genome as references, additionally a self-mapping strategy on the dataset. A subset of differentially expressed genes were analyzed and validated by in situ hybridization. The comparison of different analyses allowed us to isolate stringent sets of target genes, including transcripts with potential involvement in the onset of a non-embryonic developmental pathway. The results provide a good entry point to approach regenerative event in a basal chordate.