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1.
Almost nothing is known about how non-scientists in coastal communities perceive corals. This study investigated public perception at a coastal town in Brazil. Individuals were asked to respond to specific questions concerning their knowledge, perception, and behaviour regarding corals. Although more interviewees believed they knew what the photograph of a gorgonian was, the stony coral pictures were identified correctly more frequently. Interviewees sometimes thought that the gorgonian was a plant, whereas stony corals were frequently identified as sponges, sea urchins or stones. Interviewees related the word “coral” to words such as alive, sea, plant, rock, animal, hurt, calcareous and jewellery. Moreover, interviewees intended to buy or collect corals no matter whether they knew what they were. This study revealed that people living, working and holidaying in a coastal town in Brazil have a poor understanding of corals.  相似文献   

2.
Despite their simple body plan, stony corals (order Scleractinia, phylum Cnidaria) can produce massive and complex exoskeletal structures in shallow, tropical and subtropical regions of Earth’s oceans. The species-specific macromorphologies of their aragonite skeletons suggest a highly coordinated biomineralization process that is rooted in their genomes, and which has persisted across major climatic shifts over the past 400 + million years. The mechanisms by which stony corals produce their skeletons has been the subject of interest for at least the last 160 years, and the pace of understanding the process has increased dramatically in the past decade since the sequencing of the first coral genome in 2011. In this review, we detail what is known to date about the genetic basis of the stony coral biomineralization process, with a focus on advances in the last several years as well as ways that physical and chemical tools can be combined with genetics, and then propose next steps forward for the coming decade.  相似文献   

3.
The olive tree (Olea europaea L., Oleaceae) is one of the most important fruit trees in Mediterranean basin and has been associated with numerous biological assets. These effects have been mainly attributed to certain phenolic compounds found in fruits, olive oil and by-products of olive oil production. However, other Olea organs such as stems, roots and drupe stones have received little attention leading to limited knowledge about their phytochemical content. Thus, the main goal of the current study was the investigation of the chemical composition of diverse organs from two O. europaea varieties (i.e. Koroneiki and Chetoui) using combinations of modern analytical techniques. A fast UHPLC-DAD-FLD method was developed and applied for the profiling of different extracts of O. europaea organs as well as for the quantification of oleuropein. In addition, a dereplication strategy was developed using an Orbitrap platform (UHPLC-ESI-HRMS/MS) aiming to further characterization of the contained secondary metabolites. In total, 86 molecules were identified including compounds described for the first time in O. europaea such as coumarins. Some compounds were found to be organ specific such as nuzhenide derivatives in stone, flavonoids in leaves and oleuropein which was mainly found in Olea roots, in both varieties. Overall, it is noticeable that except olive oil, diverse organs of olive tree might comprise an alternative and valuable source of biologically active compounds.  相似文献   

4.
Molybdenum, vanadium and tungsten compounds are widely applied as analytical reagents for determination of numerous pharmacologically active substances and different biochemical parameters. Recent data from the available literature pointed to a very potent biomedical activity of compounds containing these trace elements. The present paper represents a survey on the structure and chemical properties of these compounds, as well as on their biological activity, mostly based on their interaction with cations of biomolecules, such as phospholipids and proteins. Besides, their potent inhibitory effects on cellular targets, bacterial and viral DNA and RNA polymerases will be discussed, as well. Numerous authors clearly demonstrated the antiviral (especially anti-HIV), anticoagulant and antineoplastic properties of the compounds containing the above trace elements. It has been also shown that these compounds act on some cellular enzymatic systems leading to the normalisation of blood pressure, blood glucose and serum lipid levels. Also, compounds of these trace elements represent potent antiobesity agents and express hepatoprotective and antioxidative stress activity.  相似文献   

5.
Hard, or stony, corals make rocks that can, on geological time scales, lead to the formation of massive reefs in shallow tropical and subtropical seas. In both historical and contemporary oceans, reef‐building corals retain information about the marine environment in their skeletons, which is an organic–inorganic composite material. The elemental and isotopic composition of their skeletons is frequently used to reconstruct the environmental history of Earth's oceans over time, including temperature, pH, and salinity. Interpretation of this information requires knowledge of how the organisms formed their skeletons. The basic mechanism of formation of calcium carbonate skeleton in stony corals has been studied for decades. While some researchers consider coral skeletons as mainly passive recorders of ocean conditions, it has become increasingly clear that biological processes play key roles in the biomineralization mechanism. Understanding the role of the animal in living stony coral biomineralization and how it evolved has profound implications for interpreting environmental signatures in fossil corals to understand past ocean conditions. Here we review historical hypotheses and discuss the present understanding of how corals evolved and how their skeletons changed over geological time. We specifically explain how biological processes, particularly those occurring at the subcellular level, critically control the formation of calcium carbonate structures. We examine the different models that address the current debate including the tissue–skeleton interface, skeletal organic matrix, and biomineralization pathways. Finally, we consider how understanding the biological control of coral biomineralization is critical to informing future models of coral vulnerability to inevitable global change, particularly increasing ocean acidification.  相似文献   

6.
Many animals that possess a gizzard swallow stones or sandy grit, supposedly to aid in the mechanical breakdown of food. While this has been well documented in the literature, our study is the first to report the presence of stones in the gizzard of king penguin chicks. We found stones, so called ‘gastroliths’, in the pyloric region of the gizzard, the part of the digestive tract that is specialised for the mechanical breakdown of food. Stones were already present in the gizzard of chicks and, hence, during the first year of the life of king penguins, which is spent on land. Some chicks were found to have more than 130 stones (0.5–22 mm in size) in their gizzard. The gastroliths we found in king penguins are of the same geological origin as rocks present at the colony, which suggests that birds swallowed them there. The functional role of gastroliths in penguin chicks and adults is still unknown. We discuss the potential roles that these gastroliths might play in king penguins (i.e. aid in digestion, buoyancy control during foraging at sea, adaptation to fasting).  相似文献   

7.
8.
Cyrtograpsus angulatus andChasmagnathus granulata (Grapsidae) are the two dominant decapod crustacean species in the outer parts of Mar Chiquita Lagoon, the southernmost in a series of coastal lagoons that occur along the temperate Atlantic coasts of South America. Distribution and habitat preferences (water and sediment type) in these crab species were studied in late spring. There is evidence of ontogenetic changes in habitat selection of both species. Recruitment ofC. angulatus takes place mainly in crevices of tube-building polychaete (Ficopomatus enigmaticus) “reefs” and, to a lesser extent, also in other protected microhabitats (under stones). In the latter, mostly somewhat larger juveniles were found, suggesting that these are used as a refuge for growing individuals. Adults are most frequently found on unprotected muddy and sandy beaches.C. angulatus was found in all parts of Mar Chiquita Lagoon, including freshwater, brackish, and marine habitats.C. granulata, in contrast, was restricted to the lower parts of the lagoon, where brackish water predominates and freshwater or marine conditions occur only exceptionally. It showed highest population density on “dry mud” flats and inSpartina densiflora grassland, where it can build stable burrows and where high contents of organic matter occur in the sediment. Such habitats are characterized by mixed populations of juveniles (including newly settled recruits) and adults, males and females (including a high percentage of ovigerous). Unstable “wet mud” as well as stony sand were found to be inhabited by chiefly adult populations, with only few ovigerous females. In “dry mud” flats, the proportion of males increased vertically with increasing level in the intertidal zone, showing a significantly increasing trend also in their average body size. These observations may be explained by higher resistance of males, in particular of large individuals, to desiccation, salinity, and temperature stress occurring in the upper intertidal. However, an opposite, or no such, tendency was found in the distribution of ovigerous and non-ovigerous females, respectively. With increasing distance from the water edge, salinity increased and pH decreased significantly inC. granulata burrows, whereas temperature showed no consistent tendency within the intertidal gradient. A highly significant linear relationship (r=−0.794; P<0.001) between salinity and pH in water from crab burrows is described. This regression line is significantly different from one that had been observed in water from the lagoon, indicating consistently lower pH values at any salinity level in burrow water. This is interpreted as a result of crab and/or microbial respiration.  相似文献   

9.
10.
Situated in arid area, the «banc d'Arguin landscomposes a littoraly and sandy biotope. Some stony headland could be found on the sea side.The malacofauna belongs to the senegalian type but look impoverished. Therefore, one can found some lusitanian species mainly on stones and six endemic species of the senegalo-mauretanian littoral. With the same lusitanian influences and the same endemic species, the quaternary fauna looks like the actual one belonging to the senegalian type.  相似文献   

11.
Methylene blue was synthesized in 1877 and soon found application in medicine, staining for microscopy and as an industrial dye and pigment. An enormous literature has accumulated since its introduction. Early on, it was known that methylene blue could be degraded easily by demethylation; consequently, the purity of commercial samples often was low. Therefore, demethylation products, such as azures and methylene violet, also are considered here. The names and identity of the components, their varying modes of manufacture, analytical methods and their contribution to biological staining are discussed.  相似文献   

12.
Conservation genetics and the resilience of reef-building corals   总被引:1,自引:0,他引:1  
Coral reefs have suffered long-term decline due to a range of anthropogenic disturbances and are now also under threat from climate change. For appropriate management of these vulnerable and valuable ecosystems it is important to understand the factors and processes that determine their resilience and that of the organisms inhabiting them, as well as those that have led to existing patterns of coral reef biodiversity. The scleractinian (stony) corals deposit the structural framework that supports and promotes the maintenance of biological diversity and complexity of coral reefs, and as such, are major components of these ecosystems. The success of reef-building corals is related to their obligate symbiotic association with dinoflagellates of the genus Symbiodinium. These one-celled algal symbionts (zooxanthellae) live in the endodermal tissues of their coral host, provide most of the host's energy budget and promote rapid calcification. Furthermore, zooxanthellae are the main primary producers on coral reefs due to the oligotrophic nature of the surrounding waters. In this review paper, we summarize and critically evaluate studies that have employed genetics and/or molecular biology in examining questions relating to the evolution and ecology of reef-building corals and their algal endosymbionts, and that bear relevance to coral reef conservation. We discuss how these studies can focus future efforts, and examine how these approaches enhance our understanding of the resilience of reef-building corals.  相似文献   

13.
The African cyprinid genus Labeobarbus is characterized by a high polymorphism in mouth morphology. The association between four species of this genus (two chiselmouths, one rubberlip with a well-developed fleshy mental lobe on the lower jaw, i.e., a fleshy appendage on the chin, and one usually with a poorly developed one) and 26 environmental variables was investigated in four affluents of the Luhoho River in the Albertine Highlands of the Upper Congo basin. A combination of univariate and multivariate analyses suggested that differences exist in habitat composition at localities where different Labeobarbus species were reported, and within different mouth phenotypes. The association of L. longidorsalis with the presence of cobbles and pebbles and of L. brauni with the presence of boulders suggests that the occurrence of chiselmouths phenotype is associated with stony habitats, whereas phenotypes with a mental lobe, i.e., Labeobarbus longifilis and L. paucisquamatus, mostly occupy habitats without stones. Differences in the distribution between these two species appear to be linked to physico-chemical parameters such as electrical conductivity and water temperature rather than substrate type. The findings of this study are relevant for developing guidelines that aim effective local preservation and conservation of these Labeobarbus species.  相似文献   

14.
The role of oligo-elements such as Zn in the genesis of pathological calcifications is widely debated in the literature. An essential element of discussion is given by their localisation either at the surface or within the Ca apatite crystalline network. To determine the localisation, X-ray absorption experiments have been performed at SOLEIL. The Exafs results suggest that Zn atoms, present in the Zn2+ form, are bound to about 4 O atoms at a distance of 2.00 Å, while the interatomic distance RCaO ranges between 2.35 Å and 2.71 Å. Taking into account the content of Zn (around 1000 ppm) and the difference in ionic radius between Zn2+ (0.074 nm) and Ca2+ (0.099 nm), a significant longer interatomic distance would be expected in the case of Zn replacing Ca within the apatite crystalline network. We thus conclude that Zn atoms are localised at the surface and not in the apatite nanocrystal structure. Such structural result has essential biological implications for at least two reasons. Some oligoelements have a marked effect on the transformation of chemical phases, and may modify the morphology of crystals. These are both major issues because, in the case of kidney stones, the medical treatment depends strongly on the precise chemical phase and on the morphology of the biological entities at both macroscopic and mesoscopic scales.  相似文献   

15.
Abstract Most ecologists are comfortable with the notion of habitats as recognizable entities and also with situations where the junction between two adjacent habitats forms a discrete edge. Such edges form naturally because of sharp changes in important edaphic, geomorphological, climatic or chemical properties to which plants, in particular, respond. Less clear is the effect of such edges on assemblages of mobile organisms, especially invertebrates that operate at relatively small spatial scales. The objective of the present study was to sample invertebrate composition across a natural edge between a well‐developed riparian habitat on fluvial sands and a saltbush habitat developed on a stony gibber plain in a semi‐arid region of New South Wales, Australia. A total of 150 pitfall traps on five 1‐km‐long transects that straddled the edge produced more than 13 000 adult specimens from 21 ordinal invertebrate taxa. A total of 10 446 beetle, ant, wasp, fly and springtail specimens were further sorted into 426 morphospecies. Comparisons and estimates of trends in abundance and richness were made, along with computation of multivariate dissimilarity and permutation statistics, to determine if the land system edge was coincident with changes in invertebrate abundance and composition. These analyses were unable to detect disjunctions in diversity coincident with the edge. The data suggest that many taxa are either present consistently in both habitats or are mostly found in one habitat but ‘leak’ several hundred metres across into the other. Few taxa were unique to either habitat. The result is that assemblage composition for invertebrates changes gradually over distances of up to 400 m either side of the edge and that the distance to a recognizable change in composition is taxon dependent. Even sharp habitat edges, as defined by discrete changes in soils and plants, are not edges but broad transition zones for many invertebrate taxa. There are several implications of these results, especially for landscape ecology.  相似文献   

16.
17.
Stilbenes are a class of phenolic metabolites found in various edible plants, such as grapevine, berries and peanuts. Their bioactivitiy and their potential benefits for human health have been the subject of several studies. Among all identified stilbenes, resveratrol has been particularly studied and results from literature showed that it presents several biological activities, including antioxidant, anti-inflammatory and antiproliferative effects. Likewise, some researches focused on other stilbenes and highlighted similar biological activity for those compounds. However, stilbenes present a high diversity in their phenolic structures (various chemical substituents and polymerization) which is a determining factor of their absorption and metabolism rates. Consequently, this could affect the effectiveness of stilbenes in vivo. In this context, an evaluation of the bioavailability and metabolism of stilbenes is necessary to move forward with pharmacological and clinical studies. Hence, this review aims to present recently obtained data and results concerning stilbenes sources and bioavailability, as a contribution to the valorization of the role of dietary stilbenes in the human diet.  相似文献   

18.
Quantitative samples of benthos were taken on a stony beach in the maritime Antarctic (Admiralty Bay, King George Island, South Shetland Islands) during a complete annual cycle. The sampled habitat consisted of cobbles lying on sand and gravel in the fringe between the littoral and sublittoral zones; samples were always taken at low tide just below the water line. In this habitat, abundant macroalgal detritus was observed between stones. This stony beach appeared to be very rich in vagile fauna settled between and under stones. Macrobenthos consisted mainly of amphipods (ca. 85% of total number), gastropods (11%) and nemerteans (3%). The abundance of whole macrofauna ranged to over 50,000 ind. m-2 and its biomass over 600 g m-2 (FW). Seven species of Amphipoda and four species of Gastropoda were found. Amphipoda were dominated by Gondogeneia antarctica (over 70% of all amphipods) and Paramoera edouardi (over 20%), whereas among gastropods Laevilitorina antarctica prevailed (over 70%). Unexpectedly high abundance and biomass of Amphipoda were observed in the first half of winter (May/July), surpassing otherwise important summer amphipod abundance. The probable reason for this phenomenon could be high autumn abundance of decaying algae on the beach in the tidal zone, providing detritus that is probably the main food source for Amphipoda.  相似文献   

19.
Genetics is an immense science and the current developments in its methods and techniques as well as the fast emerging tools make it one of the most powerful biological sciences. Indeed, from taxonomy and ecology to physiology and molecular biology, every biological science makes use of genetics techniques and methods at one time or another. In fact, development in genetics is such that it is now possible to characterize and analyze the expression of the whole set of genes of virtually every living organism, even if it is a non-model one. Locusts are notorious for the damage they cause to the ecosystems and economies of the areas affected by their recurrent population outbreaks. To prevent and deal with these outbreaks, we now count on both biological as well as chemical agents that are proving to be successful in reducing the damage that otherwise locust population outbreaks might cause. However, a better, efficient and environmentally friendly solution is still a hoped-for target. In my opinion, the ideal future pesticide should be both environmentally friendly, risk free and species-specific. To reach the knowledge needed for the development of such species-specific anti-locust agent, deep and accurate knowledge of the locusts’ genetics and molecular biology is a must. Since genes and their expression levels lie at the bottom of every biological phenomenon, any species-specific solution to the locust problem requires a good knowledge of these organisms’ genes as well as the quantitative and spatio-temporal dynamics of their expression. To reach such knowledge, collaborative work is needed as well as a clear workflow that, given the fast development in the genetics tools, is not always clear to all research groups. For this reason, here I describe a genetics workflow that should allow taking advantage of the most recent genetics tools and techniques to answer question relating to locust biology. My hope is that the adoption of this and other work strategies by different research groups, especially when the work is a collaborative one, would provide precious information on the biology and the biological phenomena that these economically important organisms exhibit.  相似文献   

20.
A guild of leeches and triclads coexist and are the most numerous invertebrate predators on the stony shores of productive British lakes. Populations of all species are food-limited. Mortality of recruited young is considerably higher in leech than in triclad populations, and this paper investigates reasons for this. In particular, the feeding success of young leeches and triclads in relation to prey species, prey size, prey condition (alive or crushed), spatial heterogeneity (with or without the presence of stones or gravel), and the presence or absence of other young or adults predators (leeches or triclads) of the same or different species are investigated in the laboratory. Feeding success by young leeches and triclads on crushed prey without the presence of stones was high, but declined dramatically in leeches but not triclads when stones were present. Young leeches and triclads were inept at capturing live prey, of a small or large size, with the exception of soft-bodied prey such as oligochaetes. Feeding success by young predators on live prey was not increased by the presence of other young predators of the same or different species. With only a few exceptions, the presence of adult leeches, and to a much lesser extent adult triclads, increased the feeding success, growth and survival of young leeches and triclads. It is concluded that the high mortality of young leeches, compared to triclads, in field populations is due to their inability to locate damaged food in an environment with spatial heterogeneity due to a poorly developed chemosensory system. High and low levels of juvenile morality are accompanied by high and low reproductive rates in leech and triclad populations, respectively. It is unusual for a food limited population to have a high level of recruitment, but it is speculated that the characteristically high reproductive output in parasitic leeches, from which predaceous leeches are derived or have affinities, has been retained to counterbalance high juvenile mortality rates.  相似文献   

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