Percorrer por autor "Lima, Fernando P."
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- Drivers of Cape Verde archipelagic endemism in keyhole limpetsPublication . Lopes Da Cunha, Regina; Assis, J.; Madeira, Celine; Seabra, Rui; Lima, Fernando P.; Lopes, Evandro P.; Williams, Suzanne T.; Castilho, RitaOceanic archipelagos are the ideal setting for investigating processes that shape species assemblages. Focusing on keyhole limpets, genera Fissurella and Diodora from Cape Verde Islands, we used an integrative approach combining molecular phylogenetics with ocean transport simulations to infer species distribution patterns and analyse connectivity. Dispersal simulations, using pelagic larval duration and ocean currents as proxies, showed a reduced level of connectivity despite short distances between some of the islands. It is suggested that dispersal and persistence driven by patterns of oceanic circulation favouring self-recruitment played a primary role in explaining contemporary species distributions. Mitochondrial and nuclear data revealed the existence of eight Cape Verde endemic lineages, seven within Fissurella, distributed across the archipelago, and one within Diodora restricted to Boavista. The estimated origins for endemic Fissurella and Diodora were 10.2 and 6.7 MY, respectively. Between 9.5 and 4.5 MY, an intense period of volcanism in Boavista might have affected Diodora, preventing its diversification. Having originated earlier, Fissurella might have had more opportunities to disperse to other islands and speciate before those events. Bayesian analyses showed increased diversification rates in Fissurella possibly promoted by low sea levels during Plio-Pleistocene, which further explain differences in species richness between both genera.
- Environmentally relevant concentrations of microplastics and phenanthrene show limited effects on the behaviour and physiology of green crab lineagesPublication . Cozzolino, Lorenzo; Nicastro, Katy R.; McQuaid, Christopher D.; Halldórsson, Halldór P.; Lima, Fernando P.; Zardi, Gerardo I.Plastic pollution is a growing environmental concern, with microplastics (MPs) and associated contaminants such as polycyclic aromatic hydrocarbons (PAHs) jeopardising the resilience and long-term survival of marine species. While species-specific effects have been well-documented, the role of intraspecific diversity in modulating species’ responses to these contaminants remains largely neglected. This study investigates whether genetically distinct lineages of the green crab (Carcinus maenas) differ in their behavioural and physiological responses to environmentally relevant concentrations of polyethylene microplastics (PE) and PE contaminated with phenanthrene (PE+PHE). Juvenile crabs from the Southwest European (SWE) and Icelandic (ICE) populations were exposed to control seawater, PE, or PE+PHE for 72 h, and their behavioural (i.e., food contest) and physiological performances (i.e., heart rate) were assessed. Overall, there were no significant effects of PE or PE+PHE on key behavioural traits related to food competition (e.g., latency to initiate movement, interbout intervals, contest outcome) or on physiological parameters such as heart rate. However, resource possession was significantly reduced in ICE crabs exposed to PE. Our findings suggest that C. maenas exhibits short-term resilience to MPs and PAHs, with similar behavioural responses across distinct genotypic lineages (SWE = ICE). However, differences in heart rates between genetically distinct populations, even in control conditions, highlight the potential effect of lineage-specific physiological plasticity. In addition, high inter-individual variability in behavioural responses suggests susceptibility to MPs and PAHs may not be uniform within populations. Long-term assessments incorporating individual-based analyses are needed to fully understand the complex interplay between plastic pollution, genetic diversity, and behavioural plasticity in this marine species.
- Evolution at a different pace: distinctive phylogenetic patterns of cone snails from two ancient oceanic archipelagosPublication . Cunha, Regina L.; Lima, Fernando P.; Tenorio, Manuel J.; Ramos, Ana A.; Castilho, Rita; Williams, Suzanne T.Ancient oceanic archipelagos of similar geological age are expected to accrue comparable numbers of endemic lineages with identical life history strategies, especially if the islands exhibit analogous habitats. We tested this hypothesis using marine snails of the genus Conus from the Atlantic archipelagos of Cape Verde and Canary Islands. Together with Azores and Madeira, these archipelagos comprise the Macaronesia biogeographic region and differ remarkably in the diversity of this group. More than 50 endemic Conus species have been described from Cape Verde, whereas prior to this study, only two nonendemic species, including a putative species complex, were thought to occur in the Canary Islands. We combined molecular phylogenetic data and geometric morphometrics with bathymetric and paleoclimatic reconstructions to understand the contrasting diversification patterns found in these regions. Our results suggest that species diversity is even lower than previously thought in the Canary Islands, with the putative species complex corresponding to a single species, Conus guanche. One explanation for the enormous disparity in Conus diversity is that the amount of available habitat may differ, or may have differed in the past due to eustatic (global) sea level changes. Historical bathymetric data, however, indicated that sea level fluctuations since the Miocene have had a similar impact on the available habitat area in both Cape Verde and Canary archipelagos and therefore do not explain this disparity. We suggest that recurrent gene flow between the Canary Islands and West Africa, habitat losses due to intense volcanic activity in combination with unsuccessful colonization of new Conus species from more diverse regions, were all determinant in shaping diversity patterns within the Canarian archipelago. Worldwide Conus species diversity follows the well-established pattern of latitudinal increase of species richness from the poles towards the tropics. However, the eastern Atlantic revealed a striking pattern with two main peaks of Conus species richness in the subtropical area and decreasing diversities toward the tropical western African coast. A Random Forests model using 12 oceanographic variables suggested that sea surface temperature is the main determinant of Conus diversity either at continental scales (eastern Atlantic coast) or in a broader context (worldwide). Other factors such as availability of suitable habitat and reduced salinity due to the influx of large rivers in the tropical area also play an important role in shaping Conus diversity patterns in the western coast of Africa.
- Intraspecific variations in oyster (Magallana gigas) ploidy does not affect physiological responses to microplastic pollutionPublication . Cozzolino, Lorenzo; Nicastro, Katy R.; Detree, Camille; Gribouval, Laura; Seuront, Laurent; Lima, Fernando P.; McQuaid, Christopher D.; Zardi, Gerardo I.Recent advances in genetic manipulation such as triploid breeding and artificial selection, have rapidly emerged as valuable hatchery methodologies for enhancing seafood stocks. The Pacific oyster Magallana gigas is a leading aquaculture species worldwide and key ecosystem engineer that has received particular attention in this field of science. In light of the growing recognition of the ecological effects of intraspecific variation, oyster polyploids provide a valuable opportunity to assess whether intraspecific diversity affects physiological responses to environmental stressors. While the responses of diploid and triploid oysters to climate change have been extensively investigated, research on their sensitivity to environmental pollution remains scarce. Here, we assess whether genotypic (i.e., ploidy) variation within Magallana gigas affects physiological responses to microplastic pollution. We show that diploid and triploid M. gigas have similar clearance rates and ingest similar amounts of microplastics under laboratory-controlled condition. In addition, they exhibited similar heart rates after prolonged exposure to microplastic leachates. Our findings suggest that intraspecific variations within M. gigas ploidy does not affect oyster responses to microplastic pollution. However, regardless of ploidy, our work highlights significant adverse effects of microplastic leachates on the heart rate of M. gigas and provides evidence of microplastic ingestion in the laboratory.
- Thermal adaptation and clinal mitochondrial DNA variation of European anchovyPublication . Silva, Goncalo; Lima, Fernando P.; Martel, Paulo; Castilho, RitaNatural populations of widely distributed organisms often exhibit genetic clinal variation over their geographical ranges. The European anchovy, Engraulis encrasicolus, illustrates this by displaying a two-clade mitochondrial structure clinally arranged along the eastern Atlantic. One clade has low frequencies at higher latitudes, whereas the other has an anti-tropical distribution, with frequencies decreasing towards the tropics. The distribution pattern of these clades has been explained as a consequence of secondary contact after an ancient geographical isolation. However, it is not unlikely that selection acts on mitochondria whose genes are involved in relevant oxidative phosphorylation processes. In this study, we performed selection tests on a fragment of 1044 bp of the mitochondrial cytochrome b gene using 455 individuals from 18 locations. We also tested correlations of six environmental features: temperature, salinity, apparent oxygen utilization and nutrient concentrations of phosphate, nitrate and silicate, on a compilation of mitochondrial clade frequencies from 66 sampling sites comprising 2776 specimens from previously published studies. Positive selection in a single codon was detected predominantly (99%) in the anti-tropical clade and temperature was the most relevant environmental predictor, contributing with 59% of the variance in the geographical distribution of clade frequencies. These findings strongly suggest that temperature is shaping the contemporary distribution of mitochondrial DNA clade frequencies in the European anchovy.