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1.
Environ Manage ; 73(3): 634-645, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38006452

RESUMO

Ecosystem services (ES) embrace contributions of nature to human livelihood and well-being. Reef environments provide a range of ES with direct and indirect contributions to people. However, the health of reef environments is declining globally due to local and large-scale threats, affecting ES delivery in different ways. Mapping scientific knowledge and identifying research gaps on reefs' ES is critical to guide their management and conservation. We conducted a systematic assessment of peer-reviewed articles published between 2007 and 2022 to build an overview of ES research on reef environments. We analyzed the geographical distribution, reef types, approaches used to assess ES, and the potential drivers of change in ES delivery reported across these studies. Based on 115 articles, our results revealed that coral and oyster reefs are the most studied reef ecosystems. Cultural ES (e.g., subcategories recreation and tourism) was the most studied ES in high-income countries, while regulating and maintenance ES (e.g., subcategory life cycle maintenance) prevailed in low and middle-income countries. Research efforts on reef ES are biased toward the Global North, mainly North America and Oceania. Studies predominantly used observational approaches to assess ES, with a marked increase in the number of studies using statistical modeling during 2021 and 2022. The scale of studies was mostly local and regional, and the studies addressed mainly one or two subcategories of reefs' ES. Overexploitation, reef degradation, and pollution were the most commonly cited drivers affecting the delivery of provisioning, regulating and maintenance, and cultural ES. With increasing threats to reef environments, the growing demand for assessing the contributions to humans provided by reefs will benefit the projections on how these ES will be impacted by anthropogenic pressures. The incorporation of multiple and synergistic ecosystem mechanisms is paramount to providing a comprehensive ES assessment, and improving the understanding of functions, services, and benefits.


Assuntos
Antozoários , Ecossistema , Animais , Humanos , Recifes de Corais , Conservação dos Recursos Naturais/métodos , Antozoários/fisiologia , Modelos Estatísticos
2.
J Fish Biol ; 103(2): 324-335, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37169731

RESUMO

Density-dependent mechanisms and habitat use are important drivers of marine spatial distribution in complex ecosystems such as coral or rocky reefs. In the last decade, a few studies have assessed habitat use by reef fishes in nearshore and coastal environments along the Brazilian coast. Serranidae (groupers and sea basses) are regarded as excellent models for understanding habitat use patterns due to their diversity, long lifespan, wide distribution, morphological and functional diversity, and behavioural complexity. Their trophic position in the food web, from meso- to top-predators, grants them critical roles as top-down population controllers. Herein, we present the first assessment of habitat use by five sympatric Serranidae in a Brazilian oceanic island, Trindade. The model species selected for this assessment were the coney (Cephalopholis fulva), the rock hind (Epinephelus adscensionis), the greater soapfish (Rypticus saponaceus), the Creole-fish (Paranthias furcifer) and the hybrid between C. fulva and P. furcifer. Our findings revealed that the species showed specific associations with topographic characteristics related to shelter from predation, reproduction and feeding. Habitat use in Trindade was similar to that observed in nearshore coastal environments (where the hybrid is absent). The present work contributes to the knowledge of habitat use and niche partitioning among key species, which is a valuable tool to subsidize effective conservation initiatives such as designing marine protected areas focusing on the behaviour and habitat use of key ecological players.


Assuntos
Antozoários , Bass , Animais , Ecossistema , Comportamento Predatório , Peixes , Cadeia Alimentar , Recifes de Corais
3.
J Fish Biol ; 101(1): 179-189, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35538668

RESUMO

The red porgy (Pagrus pagrus) is a carnivore bottom dweller sparid, inhabiting flat sandy bottoms, rhodolith and seagrass beds of the Mediterranean Sea, the Western Atlantic (from Florida to Argentina) and the Eastern Atlantic (from Britain to Gabon). Along its native range, the red porgy is highly targeted by commercial and artisanal fisheries. In the past 40 years, the population decline of the species has been widely reported. In many locations, such as the Brazilian coast, stocks have collapsed. The central portion of the Brazilian coast harbours the largest rhodolith beds in the world and the highest levels of nektonic and benthic biodiversity. Along the rhodolith megahabitat, P. pagrus density is disproportionately higher (by 480%) than that of conspicuous benthic fishes inhabiting the same environment. Despite the ecological and economic importance of such an important species along its native range, little is known regarding its habitat use, niche availability and population responses to global warming. Here we present habitat affinities based on data sampled using baited remote stereo-video systems, and modelled niche availability and global warming populational responses. Our findings reveal that the red porgy is a species highly associated with rhodolith beds along the central portion of the Brazilian coast. The presence of a disproportional density and biomass of the red porgy, compared to other marine fish species, indicates that the species plays a key ecological role as a carnivore, mesoconsumer and prey/predator tolerant species, maintaining essential ecological functions in the habitat. In a global warming scenario, the model predicted populational niche shifts poleward and a severe niche erosion at lower latitudes as expected. Conservation initiatives (implementation of Maine Protected Areas, trawling exclusion zones, mining exclusion zones, fisheries management policies) are urgent to secure future stocks of the red porgy and also preserve the fragile rhodolith beds they inhabit.


Assuntos
Ecossistema , Perciformes , Animais , Biodiversidade , Peixes , Mar Mediterrâneo
4.
Neotrop. ichthyol ; 20(3)2022. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1396136

RESUMO

The genus Acyrtus (Gobiesocidae) is represented by four valid species distributed in the western Atlantic, and a recently described fifth species from the eastern Pacific. Here, we describe a new species endemic to Trindade Island, Brazil, and provide the first phylogenetic inference for the genus including all representatives. The new species can be distinguished from all its congeners by meristic and morphometric characters, as well as genetic differences. It presents low genetic diversity and, contrarily to other Trindade Island endemic fishes, shows no evidence of recent population growth. Our phylogeny reveals cryptic species and the paraphyletic nature of Acyrtus, which included Arcos nudus (western Atlantic) in a clade that separated from Arcos erythrops (tropical eastern Pacific) around 20 Mya. The three species found in the Brazilian Province, including one that remains undescribed, form a monophyletic clade which colonized the western South Atlantic around 2.6 Mya. Our study suggests that Arcos nudus should be placed in Acyrtus, and that the relationships among the closely-related Gobiesocidae genera Acyrtus (mostly from the Atlantic Ocean) and Arcos (from the Pacific Ocean) need further investigation.(AU)


O gênero Acyrtus (Gobiesocidae) é representado por quatro espécies válidas encontradas no Atlântico ocidental e uma recentemente descrita do Pacífico oriental. Aqui descrevemos uma nova espécie endêmica da Ilha da Trindade, Brasil, e apresentamos a primeira inferência filogenética para o gênero incluindo todos os representantes. A nova espécie pode ser distinguida de suas congêneres por caracteres merísticos e morfométricos, bem como por diferenças genéticas. A espécie apresenta baixa diversidade genética, entretanto, diferentemente de outras espécies endêmicas da Ilha da Trindade, não mostra evidência de expansão populacional recente. A filogenia obtida revelou a existência de espécies crípticas e a natureza parafilética de Acyrtus, o qual inclui Arcos nudus (do Atlântico ocidental), e que é separado de Arcos erythrops (do Pacifico tropical oriental) por cerca de 20 milhões de anos. As três espécies encontradas no Brasil, incluindo uma ainda não descrita, formam um clado monofilético que colonizou o Atlântico Sul ocidental há cerca de 2,6 milhões de anos. Nosso estudo sugere que Arcos nudus deva ser alocado no gênero Acyrtus, e que as relações entre os gêneros Acyrtus (em maioria do Oceano Atlântico) e Arcos (do Oceano Pacífico) precisam ser estudadas em mais detalhes.(AU)


Assuntos
Animais , Filogenia , Biodiversidade , Characidae/classificação , Especificidade da Espécie , Brasil
5.
J Fish Biol ; 97(4): 1143-1153, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32743800

RESUMO

Saint Peter and Saint Paul's Archipelago (SPSPA), one of the smallest and most isolated island groups in the world, is situated on the Mid-Atlantic Ridge, between Brazil and the African continent. SPSPA has low species richness and high endemism; nonetheless, the diversity of fishes from deep habitats (>30 m depth) had not been previously studied in detail. Several expeditions conducted between 2009 and 2018 explored the shallow and deep reefs of SPSPA using scuba, closed-circuit rebreathers, manned submersibles, baited remote underwater stereo-videos (stereo-BRUV) and fishing between 0 and 1050 m depth. These expeditions yielded 41 new records of fishes for SPSPA: 9 in open waters, 9 in shallow waters (0-30 m), 8 in mesophotic ecosystems (30-150 m) and 15 in deeper reefs (>150 m). Combined with literature records of adult pelagic, shallow and deep-reef species, as well as larvae, the database of the fish biodiversity for SPSPA currently comprises 225 species (169 recorded as adult fishes and 79 as larvae, with 23 species found in both stages). Most of them (112) are pelagic, 86 are reef-associated species and 27 are deep-water specialists. Species accumulation curves show that the number of fish species has not yet reached an asymptote. Whereas the number of species recorded in SPSPA is similar to that in other oceanic islands in the Atlantic Ocean, the proportion of shorefishes is relatively lower, and the endemism level is the third highest in the Atlantic. Twenty-nine species are listed as threatened with extinction. Observations confirm the paucity of top predators on shallow rocky reefs of the island, despite the presence of several pelagic shark species around SPSPA. Because all of the endemic species are reef associated, it is argued that the new marine-protected areas created by the Brazilian government do not ensure the protection and recovery of SPSPA's biodiversity because they allow exploitation of the most vulnerable species around the archipelago itself. This study suggests a ban on reef fish exploitation inside an area delimited by the 1000 m isobath around the islands (where all known endemics are concentrated) as the main conservation strategy to be included in the SPSPA management plan being prepared by the Brazilian government.


Assuntos
Biodiversidade , Bases de Dados Factuais , Peixes/classificação , Animais , Oceano Atlântico , Brasil , Recifes de Corais , Ecossistema , Ilhas , Tubarões
6.
Neotrop. ichthyol ; 18(4): [e200050], 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-27415

RESUMO

Although several studies on the ichthyofauna of the Fernando de Noronha Archipelago have been carried out, its mesophotic fish diversity has never been surveyed before. Here we used SCUBA and technical rebreather diving, baited remote underwater videos and remotely operated vehicle to record shallow (≤ 30 m depth) and mesophotic (31 to 150 m depth) fishes. Nineteen fish species belonging to 14 families are reported here as new records, representing an increase of 8.2% in marine fish richness for the region, which now has a total of 250 species and 77 families. These new records include four potential new species and highlight the importance of surveying mesophotic ecosystems, even in well studied sites. Our results also emphasize the need for protection and attention to the unique ichthyofauna found at mesophotic depths.(AU)


Apesar de muitos estudos sobre a ictiofauna do Arquipélago de Fernando de Noronha terem sido realizados, sua diversidade de peixes mesofóticos nunca foi estudada antes. Neste estudo utilizamos mergulho autônomo e mergulho técnico, vídeos subaquáticos remotos com isca e veículo operado remotamente para registrar peixes de ecossistemas rasos (≤ 30 m de profundidade) e mesofóticos (31 a 150 m de profundidade). Dezenove espécies de peixes pertencentes a 14 famílias são apresentadas aqui como novos registros, representando um aumento de 8,2% na riqueza de peixes marinhos da região, que agora possui um total de 250 espécies e 77 famílias. Esses novos registros incluem quatro prováveis novas espécies e reforçam a importância de estudos em ecossistemas mesofóticos. Nossos resultados também enfatizam a necessidade de proteção e atenção à essa ictiofauna única encontrada nesses ecossistemas profundos.(AU)


Assuntos
Animais , Ecossistema , Filogeografia , Peixes , Recursos Audiovisuais , Áreas Marinhas Protegidas/análise
7.
Neotrop. ichthyol ; 18(1): e190054, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-26797

RESUMO

Among the four butterflyfishes of the genus Chaetodon present in the western Atlantic, the banded butterflyfish Chaetodon striatus has the largest distribution range, spanning 44 degrees of latitude (from Massachusetts, USA to Santa Catarina, Brazil). Although the ecology of the banded butterflyfish has been well studied over its entire range, nothing is known about its phylogeography and how biogeographic barriers structure its populations. To assess the level of genetic connectivity among populations from distinct biogeographic provinces and environmental conditions, we collected samples from seven localities: Puerto Rico, in the Caribbean, and Tamandaré, Salvador, Abrolhos, Trindade Island, Arraial do Cabo and Florianópolis, in Brazil. One nuclear (rag 2) and two mitochondrial (control region and cyt b) molecular markers were sequenced. Our findings are consistent with a recent population expansion, around 30-120 thousand years ago, which was found for all populations. Haplotype network analyses point to the Caribbean as a refugium before the population expansion. Results show no geographic pattern of genetic diversity. Indeed, a lack of population structure was found and no isolation was observed across oceanographic barriers, as well as between coral and rocky reef ecosystems. Furthermore, no directionality in the migration pattern was found among populations. Since ecological and environmental characteristics are very diverse across such a vast geographic range, the lack of genetic differentiation suggests that C. striatus evolved ecological plasticity rather than local adaptation in the western Atlantic.(AU)


O peixe-borboleta listrado, Chaetodon striatus, possui a maior distribuição geográfica dentre as quatro espécies de peixes-borboleta do gênero Chaetodon presentes no Oceano Atlântico Ocidental, abrangendo 44° de latitude (entre Massachusetts, EUA até o sul do Brasil). A ecologia alimentar desta espécie é bastante conhecida, considerando a ampla distribuição, porém, pouco se sabe sobre a filogeografia e como as barreiras biogeográficas estruturam as populações. Para acessar a conectividade genética entre as populações de diferentes províncias biogeográficas e diferentes condições ambientais, foram coletadas amostras de sete localidades: Porto Rico, no Caribe, e Tamandaré, Salvador, Abrolhos, Ilha da Trindade, Arraial do Cabo e Florianópolis, no Brasil. Foram sequenciados um gene nuclear (rag 2) e dois genes mitocondriais (região controle e cit B). Para todas as populações, foi identificada uma expansão populacional recente, em torno de 30-120 mil anos atrás. A análise de rede de haplótipos sugere que o Caribe serviu como refúgio antes desta expansão populacional. Os resultados indicam que não há padrão geográfico de diversidade genética. Apesar da existência de barreiras oceanográficas e diferenças na constituição dos recifes (rochosos e coralíneos), não foi encontrada estruturação populacional. Também, não encontramos padrão na direção de migração entre as populações. Os resultados sugerem que C. striatus apresenta plasticidade ecológica, uma vez que não há diferenciação genética entre as populações que habitam ecossistemas tão diferentes ao longo da ampla distribuição no Atlântico Ocidental.(AU)


Assuntos
Animais , Ecossistema , Filogeografia , Filogeografia/métodos , Peixes/genética , Genes Mitocondriais
8.
Neotrop. ichthyol ; 18(1): e190054, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1098419

RESUMO

Among the four butterflyfishes of the genus Chaetodon present in the western Atlantic, the banded butterflyfish Chaetodon striatus has the largest distribution range, spanning 44 degrees of latitude (from Massachusetts, USA to Santa Catarina, Brazil). Although the ecology of the banded butterflyfish has been well studied over its entire range, nothing is known about its phylogeography and how biogeographic barriers structure its populations. To assess the level of genetic connectivity among populations from distinct biogeographic provinces and environmental conditions, we collected samples from seven localities: Puerto Rico, in the Caribbean, and Tamandaré, Salvador, Abrolhos, Trindade Island, Arraial do Cabo and Florianópolis, in Brazil. One nuclear (rag 2) and two mitochondrial (control region and cyt b) molecular markers were sequenced. Our findings are consistent with a recent population expansion, around 30-120 thousand years ago, which was found for all populations. Haplotype network analyses point to the Caribbean as a refugium before the population expansion. Results show no geographic pattern of genetic diversity. Indeed, a lack of population structure was found and no isolation was observed across oceanographic barriers, as well as between coral and rocky reef ecosystems. Furthermore, no directionality in the migration pattern was found among populations. Since ecological and environmental characteristics are very diverse across such a vast geographic range, the lack of genetic differentiation suggests that C. striatus evolved ecological plasticity rather than local adaptation in the western Atlantic.(AU)


O peixe-borboleta listrado, Chaetodon striatus, possui a maior distribuição geográfica dentre as quatro espécies de peixes-borboleta do gênero Chaetodon presentes no Oceano Atlântico Ocidental, abrangendo 44° de latitude (entre Massachusetts, EUA até o sul do Brasil). A ecologia alimentar desta espécie é bastante conhecida, considerando a ampla distribuição, porém, pouco se sabe sobre a filogeografia e como as barreiras biogeográficas estruturam as populações. Para acessar a conectividade genética entre as populações de diferentes províncias biogeográficas e diferentes condições ambientais, foram coletadas amostras de sete localidades: Porto Rico, no Caribe, e Tamandaré, Salvador, Abrolhos, Ilha da Trindade, Arraial do Cabo e Florianópolis, no Brasil. Foram sequenciados um gene nuclear (rag 2) e dois genes mitocondriais (região controle e cit B). Para todas as populações, foi identificada uma expansão populacional recente, em torno de 30-120 mil anos atrás. A análise de rede de haplótipos sugere que o Caribe serviu como refúgio antes desta expansão populacional. Os resultados indicam que não há padrão geográfico de diversidade genética. Apesar da existência de barreiras oceanográficas e diferenças na constituição dos recifes (rochosos e coralíneos), não foi encontrada estruturação populacional. Também, não encontramos padrão na direção de migração entre as populações. Os resultados sugerem que C. striatus apresenta plasticidade ecológica, uma vez que não há diferenciação genética entre as populações que habitam ecossistemas tão diferentes ao longo da ampla distribuição no Atlântico Ocidental.(AU)


Assuntos
Animais , Ecossistema , Filogeografia , Filogeografia/métodos , Peixes/genética , Genes Mitocondriais
9.
Neotrop. ichthyol ; 18(4): e200050, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1143349

RESUMO

Abstract Although several studies on the ichthyofauna of the Fernando de Noronha Archipelago have been carried out, its mesophotic fish diversity has never been surveyed before. Here we used SCUBA and technical rebreather diving, baited remote underwater videos and remotely operated vehicle to record shallow (≤ 30 m depth) and mesophotic (31 to 150 m depth) fishes. Nineteen fish species belonging to 14 families are reported here as new records, representing an increase of 8.2% in marine fish richness for the region, which now has a total of 250 species and 77 families. These new records include four potential new species and highlight the importance of surveying mesophotic ecosystems, even in well studied sites. Our results also emphasize the need for protection and attention to the unique ichthyofauna found at mesophotic depths.(AU)


Resumo Apesar de muitos estudos sobre a ictiofauna do Arquipélago de Fernando de Noronha terem sido realizados, sua diversidade de peixes mesofóticos nunca foi estudada antes. Neste estudo utilizamos mergulho autônomo e mergulho técnico, vídeos subaquáticos remotos com isca e veículo operado remotamente para registrar peixes de ecossistemas rasos (≤ 30 m de profundidade) e mesofóticos (31 a 150 m de profundidade). Dezenove espécies de peixes pertencentes a 14 famílias são apresentadas aqui como novos registros, representando um aumento de 8,2% na riqueza de peixes marinhos da região, que agora possui um total de 250 espécies e 77 famílias. Esses novos registros incluem quatro prováveis novas espécies e reforçam a importância de estudos em ecossistemas mesofóticos. Nossos resultados também enfatizam a necessidade de proteção e atenção à essa ictiofauna única encontrada nesses ecossistemas profundos.(AU)


Assuntos
Animais , Ecossistema , Peixes , Recursos Audiovisuais , Áreas Marinhas Protegidas/análise
10.
St. Augustine; The University of the West Indies, Faulty of Medical Sciences; November 9, 2017.
Não convencional em Inglês | MedCarib | ID: biblio-986563

RESUMO

Prostate cancer is the third leading cause of cancer death among men worldwide and is the leading cause of cancer mortality in males greater than 60 years in Trinidad and Tobago. Although there are some treatment options for the metastatic disease, the impact on overall survival rate has not improved in the last two decades. In particular, the mortality rate from prostate cancer is high among men of African descent in Trinidad and Tobago and the Americas. These groups manifest aggressive cancers that are often less responsive to available therapies. We hypothesize that phytochemical screening of tropical plants, coupled to cell culture studies would identify other potential treatments for prostate cancer. In separate experiments, the roots or leaves of five plants indigenous to the Caribbean and the skin of the muscadine grape, indigenous to North America were dried, crushed and suspended in 100% methanol. The respective methanol extracts were fractionated and the fractions dried. Next the ability of the extracts to halt the growth of or kill PC-3 prostate cancer cells was assessed by MTT assays. Colony formation, cell migration studies, cell cycle studies and western blots were performed to determine probable mechanism of action. The categories of chemical compounds present in the extracts were determined by Thin Layer chromatography (TLC). Results from MTT assays showed that compared to the control cells (ie those treated with DMSO only), treatment with at least four plant extracts significantly (p<0.05) inhibited the growth of the cancer cells; decreases as large as 95 % were observed. On the other hand these extracts had a limited or delayed effect on the "normal" PNT1A cells. Results from the cell cycle assay demonstrated that one extract, now identified as plant-A extract, caused the arrest of the G1/S phase of PC-3 cells i.e. leading to an increase in the number of cells that remained in the growth phase. On the other hand the total ethanol extract of muscadine grape skin decreased the expression of heat shock protein-40, possibly causing deactivation of the androgen receptor. This suggests that extracts prepared from Plant A and the muscadine grape have the potential for use as anticancer drugs.


Assuntos
Humanos , Masculino , Neoplasias da Próstata , Trinidad e Tobago
11.
In. Faculty of Medical Sciences. Faculty Research Day, Book of Abstracts. St. Augustine, The University of the West Indies, November 9, 2017. .
Não convencional em Inglês | MedCarib | ID: biblio-1007022

RESUMO

Prostate cancer is the third leading cause of cancer death among men worldwide and is the leading cause of cancer mortality in males greater than 60 years in Trinidad and Tobago. Although there are some treatment options for the metastatic disease, the impact on overall survival rate has not improved in the last two decades. In particular, the mortality rate from prostate cancer is high among men of African descent in Trinidad and Tobago and the Americas. These groups manifest aggressive cancers that are often less responsive to available therapies. We hypothesize that phytochemical screening of tropical plants, coupled to cell culture studies would identify other potential treatments for prostate cancer. In separate experiments, the roots or leaves of five plants indigenous to the Caribbean and the skin of the muscadine grape, indigenous to North America were dried, crushed and suspended in 100% methanol. The respective methanol extracts were fractionated and the fractions dried. Next the ability of the extracts to halt the growth of or kill PC-3 prostate cancer cells was assessed by MTT assays. Colony formation, cell migration studies, cell cycle studies and western blots were performed to determine probable mechanism of action. The categories of chemical compounds present in the extracts were determined by Thin Layer chromatography (TLC). Results from MTT assays showed that compared to the control cells (ie those treated with DMSO only), treatment with at least four plant extracts significantly (p<0.05) inhibited the growth of the cancer cells; decreases as large as 95 % were observed. On the other hand these extracts had a limited or delayed effect on the "normal" PNT1A cells. Results from the cell cycle assay demonstrated that one extract, now identified as plant-A extract, caused the arrest of the G1/S phase of PC-3 cells i.e. leading to an increase in the number of cells that remained in the growth phase. On the other hand the total ethanol extract of muscadine grape skin decreased the expression of heat shock protein-40, possibly causing deactivation of the androgen receptor. This suggests that extracts prepared from Plant A and the muscadine grape have the potential for use as anticancer drugs.


Assuntos
Humanos , Masculino , Neoplasias da Próstata , Trinidad e Tobago , Medicina Herbária
12.
Nature ; 549(7670): 82-85, 2017 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-28854164

RESUMO

Studies on the distribution and evolution of organisms on oceanic islands have advanced towards a dynamic perspective, where terrestrial endemicity results from island geographical aspects and geological history intertwined with sea-level fluctuations. Diversification on these islands may follow neutral models, decreasing over time as niches are filled, or disequilibrium states and progression rules, where richness and endemism rise with the age of the archipelago owing to the splitting of ancestral lineages (cladogenesis). However, marine organisms have received comparatively little scientific attention. Therefore, island and seamount evolutionary processes in the aquatic environment remain unclear. Here we analyse the evolutionary history of reef fishes that are endemic to a volcanic ridge of seamounts and islands to understand their relations to island evolution and sea-level fluctuations. We also test how this evolutionary history fits island biogeography theory. We found that most endemic species have evolved recently (Pleistocene epoch), during a period of recurrent sea-level changes and intermittent connectivity caused by repeated aerial exposure of seamounts, a finding that is consistent with an ephemeral ecological speciation process. Similar to findings for terrestrial biodiversity, our data suggest that the marine speciation rate on islands is negatively correlated with immigration rate. However, because marine species disperse better than terrestrial species, most niches are filled by immigration: speciation increases with the random accumulation of species with low dispersal ability, with few opportunities for in situ cladogenesis and adaptive radiation. Moreover, we confirm that sea-level fluctuations and seamount location play a critical role in marine evolution, mainly by intermittently providing stepping stones for island colonization.


Assuntos
Organismos Aquáticos/isolamento & purificação , Biodiversidade , Peixes/fisiologia , Ilhas , Filogeografia , Animais , Organismos Aquáticos/fisiologia , Oceano Atlântico , Evolução Biológica , Brasil , Recifes de Corais
14.
PLoS One ; 10(6): e0130084, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26090804

RESUMO

Seamounts are considered important sources of biodiversity and minerals. However, their biodiversity and health status are not well understood; therefore, potential conservation problems are unknown. The mesophotic reefs of the Vitória-Trindade Seamount Chain (VTC) were investigated via benthic community and fish surveys, metagenomic and water chemistry analyses, and water microbial abundance estimations. The VTC is a mosaic of reef systems and includes fleshy algae dominated rhodolith beds, crustose coralline algae (CCA) reefs, and turf algae dominated rocky reefs of varying health levels. Macro-carnivores and larger fish presented higher biomass at the CCA reefs (4.4 kg per frame) than in the rhodolith beds and rocky reefs (0.0 to 0.1 kg per frame). A larger number of metagenomic sequences identified as primary producers (e.g., Chlorophyta and Streptophyta) were found at the CCA reefs. However, the rocky reefs contained more diseased corals (>90%) than the CCA reefs (~40%) and rhodolith beds (~10%). Metagenomic analyses indicated a heterotrophic and fast-growing microbiome in rocky reef corals that may possibly lead to unhealthy conditions possibly enhanced by environmental features (e.g. light stress and high loads of labile dissolved organic carbon). VTC mounts represent important hotspots of biodiversity that deserve further conservation actions.


Assuntos
Biodiversidade , Biomassa , Recifes de Corais , Ecossistema , Peixes , Microbiologia da Água , Qualidade da Água , Animais , Oceano Atlântico , Brasil , Metagenômica
15.
PLoS One ; 10(3): e0118180, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25738798

RESUMO

Despite a strong increase in research on seamounts and oceanic islands ecology and biogeography, many basic aspects of their biodiversity are still unknown. In the southwestern Atlantic, the Vitória-Trindade Seamount Chain (VTC) extends ca. 1,200 km offshore the Brazilian continental shelf, from the Vitória seamount to the oceanic islands of Trindade and Martin Vaz. For a long time, most of the biological information available regarded its islands. Our study presents and analyzes an extensive database on the VTC fish biodiversity, built on data compiled from literature and recent scientific expeditions that assessed both shallow to mesophotic environments. A total of 273 species were recorded, 211 of which occur on seamounts and 173 at the islands. New records for seamounts or islands include 191 reef fish species and 64 depth range extensions. The structure of fish assemblages was similar between islands and seamounts, not differing in species geographic distribution, trophic composition, or spawning strategies. Main differences were related to endemism, higher at the islands, and to the number of endangered species, higher at the seamounts. Since unregulated fishing activities are common in the region, and mining activities are expected to drastically increase in the near future (carbonates on seamount summits and metals on slopes), this unique biodiversity needs urgent attention and management.


Assuntos
Biodiversidade , Peixes/fisiologia , Animais , Oceano Atlântico , Filogeografia
16.
Mar Pollut Bull ; 85(1): 252-3, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24975092

RESUMO

Invasive coral species of the genus Tubastraea have been increasingly recorded in Southwestern Atlantic waters since the 1980s. Their invasion and infestation are mainly related to port and oil exploration activities. For the first time the presence of Tubastraea tagusensis colonies is reported in Espírito Santo State, colonizing a port shore area, and incrusting oil/gas platform structures situated in the southern Abrolhos Bank, which is part of the most important coral reef system of the South Atlantic Ocean. Tubastraea colonies exhibit fast growth and high recruitment rates, and colonized 40% of the analyzed structures in just four years. The projection of port and oil/gas industry growth for the Espírito Santo State (more than 300%) highlights an alert to the dispersal of this alien species to natural areas.


Assuntos
Distribuição Animal , Antozoários/efeitos dos fármacos , Espécies Introduzidas , Animais , Oceano Atlântico , Brasil , Recifes de Corais , Meio Ambiente , Monitoramento Ambiental/métodos , Geografia , Indústria de Petróleo e Gás
17.
Mar Environ Res ; 90: 55-65, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23796542

RESUMO

In the present work fish assemblages over two metallic vessels, five and 105 years old, and two natural rocky reefs were compared. The hypothesis that shipwrecks support assemblages with trophic structure similar to that encountered on natural reefs was rejected. Artificial and natural reefs strongly differ in their trophic structure, both in their multivariate composition and in biomass of most guilds. Substrate characteristics such as rugosity and benthic cover were found to influence the trophic organisation of the communities. Moreover, slow-paced structural changes over time in both biotic and abiotic aspects of wrecks appear responsible for younger and older artificial reefs be dissimilar in respect to biomass density of most feeding guilds. However, the older artificial reef did not present any strikingly "intermediate" feature between the younger artificial reef and the natural reefs, evidencing that distinct trophic assemblages exist over wrecks. Finally, the results found indicate that the use of shipwrecks as mitigation tool for losses of natural reefs may not be fully appropriate as they greatly differ in trophic structure, and consequently in energy flow, from natural reefs. Also, setting shipwrecks near natural reefs should be avoided as they differ in resources availability for many species, which may alter the community structure of natural habitats.


Assuntos
Biota , Conservação dos Recursos Naturais/métodos , Recifes de Corais , Peixes/fisiologia , Animais , Biomassa , Brasil , Fatores de Tempo
18.
Zootaxa ; 3709: 95-100, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26240899

RESUMO

A new species of the genus Hypleurochilus, endemic to Trindade Island and Martin Vaz Archipelago, off Brazil, is described. Hypleurochilus brasil sp. n. differs from its congeners in color pattern and anal-ray counts. A recent study shows a close relationship between H. brasil sp. n. and H. fissicornis. This new species is recorded from 3 to 15 m depth, solitary or in small groups (up to 10 individuals), always in small holes or associated with sea-urchins and sponges on the rocky reefs. Hypleurochilus brasil sp. n. is the eleventh recognized species of Hypleurochilus and the third species of this genus reported from the Brazilian Province.


Assuntos
Peixes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Brasil , Ecossistema , Feminino , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento , Ilhas , Masculino , Tamanho do Órgão
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