Dispersal in the spiny damselfish,Acanthochromis polyacanthus,a coral reef fish species without a larval pelagic stage

The spiny damselfish, Acanthochromis polyacanthus, is widely distributed throughout the Indo‐Australian archipelago. However, this species lacks a larval dispersal stage and shows genetic differentiation between populations from closely spaced reefs. To investigate the dispersal strategy of this unique species, we used microsatellite markers to determine genetic relatedness at five dispersal scales: within broods of juveniles, between adults within a collection site (~30 m²), between sites on single reefs, between nearby reefs in a reef cluster, and between reef clusters. We sampled broods of juveniles and adults from seven reefs in the Capricorn‐Bunker and Swain groups of the Great Barrier Reef. We found that extra‐pair mating is rare and juveniles remain with their parents until fledged. Adults from single sites are less related than broods but more related than expected by chance. However, there is no evidence of inbreeding suggesting the existence of assortative mating and/or adult migration. Genetic differences were found between all of the reefs tested except between Heron and Sykes reefs, which are separated only by a 2‐km area of shallow water (less than 10 m). There was a strong correlation between genetic distance, geographical distance and water depth. Apparently, under present‐day conditions spiny damselfish populations are connected only between sites of shallow water, through dispersal of adults over short distances. Assuming that dispersal behaviour has not changed, the broad distribution of A. polyacanthus as a species is likely based on historical colonization patterns when reefs were connected by shallow water at times of lower sea levels.     

Exploring the nature of ecological specialization in a coral reef fish community: morphology,diet and foraging microhabitat use

Patterns of ecological specialization offer invaluable information about ecosystems. Yet, specialization is rarely quantified across several ecological niche axes and variables beyond the link between morphological and dietary specialization have received little attention. Here, we provide a quantitative evaluation of ecological specialization in a coral reef fish assemblage (f. Acanthuridae) along one fundamental and two realized niche axes. Specifically, we examined ecological specialization in 10 surgeonfish species with regards to morphology and two realized niche axes associated with diet and foraging microhabitat utilization using a recently developed multidimensional framework. We then investigated the potential relationships between morphological and behavioural specialization. These relationships differed markedly from the traditional ecomorphological paradigm. While morphological specialization showed no relationship with dietary specialization, it exhibited a strong relationship with foraging microhabitat specialization. However, this relationship was inverted: species with specialized morphologies were microhabitat generalists, whereas generalized morphotypes were microhabitat specialists. Interestingly, this mirrors relationships found in plant–pollinator communities and may also be applicable to other ecosystems, highlighting the potential importance of including niche axes beyond dietary specialization into ecomorphological frameworks. On coral reefs, it appears that morphotypes commonly perceived as most generalized may, in fact, be specialized in exploiting flat and easily accessible microhabitats.     

Shrew species diversity and abundance in Ziama Biosphere Reserve, Guinea: comparison among primary forest, degraded forest and restoration plots

The aim of our study was to compare the shrew community diversity and structure in gradients of tropical forest degradation and restoration. Four plots within each of six habitats of the Ziama Biosphere Reserve were surveyed, including primary forest, secondary forest, cultivated fields, recently (less than 3 years) abandoned fields, young (10–12 years) forest restoration plots, and old (34 years) restoration plots. From August to November 2003, we pitfall-trapped 2,509 shrews representing 11 species. Shrew species richness and composition was similar in the six habitat surveyed, while shrew species abundance varied between habitats. Canopy height and cover, density of stems and trees and understorey density were shown to constitute important parameters influencing the abundance of several shrew species. After clear-cutting, restoration of key attributes of the forest vegetation structure was possible in 10–34 years, either by natural regeneration or by planting of seedlings. The relative abundance of most shrew species was similar between restoring forest (i.e., young restoration plots or fallows) and primary forest. Considering the advantages and disadvantages of these two methods of forest restoration, one of the most suitable management practices to restore forest while preserving shrew biodiversity could be to perform an alternation of native seedling plantation lines and fallows.     

Genetic diversity and biogeography of Cunninghamia konishii (Cupressaceae), an island species in Taiwan: a comparison with Cunninghamia lanceolata, a mainland species in China

Luanta-fir (Cunninghamia konishii), an endemic to Taiwan, is an outcrossing, long-lived conifer. Populations of C. konishii are generally fragmented due to a once high intensity of timber exploitation. C. konishii and Cunninghamia lanceolata are two sibling taxa constituting derivative-progenitor species relationship. The amount of genetic variations within and between 11 and 10 populations of C. konishii and C. lanceolata, respectively, were assessed using amplified fragment length polymorphism (AFLP) markers in this report. Three AFLP primer pairs generated a total of 357 and 226 markers for C. konishii and C. lanceolata samples, of which 56.1 and 65.3% are polymorphic, respectively. Analysis of molecular variance indicates a 4.78% variation between C. konishii and C. lanceolata. A relatively high value of genetic variation (24.60%) was apportioned between the populations of C. konishii. In contrast, a lower divergence value (12.21%) between populations was found for C. lanceolata. The population with the highest genetic diversity was found in Nantou County, which concurred with the results of many other tree species investigated in Taiwan. The estimates of the number of migrants between populations (Nm), obtained from population pair-wise PhiST, suggest that gene flow in C. konishii is efficient in some adjacent populations but is restricted in the rest. Individual UPGMA tree, generated based on AFLP markers, suggests six evolutionary lineages for C. konishii. All evolutionary lineages of C. konishii were derived from C. lanceolata. In conclusion, the migration patterns of Cunninghamia from mainland China may have been established following multiple sources, migrant-pools, long-distance dispersal events, and via different directions.     

Ecosystem recovery in terra firme forests after cutting and burning: a comparison on species richness, floristic composition and forest structure in the Jaú National Park, Amazonia

Six hectares, three in a primary forest and three in a 40 year old secondary forest were inventoried for all trees with Diameter at Breast Height (DNH) of 10 cm or greater in a terra firme forest 200 km north-east of Manaus, central Amazonia in order to compare the difference between structure, species richness and floristic composition. Both species richness and tree density were significantly higher in the upland forest than in the secondary forest. The forest structure pattern analysed (DBH, basal area and estimated dry biomass) did not differ significantly between the two forest types. Similarity indices at species level were only 14%. In the 3 ha of primary forest the number of species varied from 137 to 159, the number of individuals from 639 to 713, total basal area from 32.8 to 40.2 m² and estimate total of above-ground dry biomass (AGBM) from 405 to 560 tons per ha. In the 3 ha of secondary forest, the number of species varied from 86 to 90, the number of individuals from 611 to 653, total basal area from 28.8 to 39.9 m² and estimated total AGBM from 340 to 586 tons per ha. Family Importance Value (FIV) is the sum of relative density, dominance and richness of a family. The most important families in relation to FIV were Burseraceae, Chrysobalanaceae, Lecythidaceae, Myristicaceae, Bombacaceae, Fabaceae and Mimosaceae in the 3 ha of primary forest, while Burseraceae, Lecythidaceae, Sapotaceae, Arecaceae and Cecropiaceae were the most important families in the 3 ha of secondary forest. Importance Value Index (IVI) is the sum of relative density, dominance and frequency of a species. Alexa grandiflora (Caesalpiniaceae), Sckronema micranthum (Bombacaceae) and Pourouma guianensis (Cecropiaceae) were the most important species in relation IVI, in the primary forest, while Eschweilera grandiflora (Lecythidaceae), Protium apiculatum (Burseraceae) and Bertholletia excelsa (Lecythidaceae) were the most important species in the secondary forest. We conclude that species richness was significandy different between the two forests, but that forest structure patterns analysed in this study (DBH, basal area and dry biomass) were similar. This demonstrates that 40 years was sufficient time for the secondary forest to recover the original structure of the primary forest, but not the original species richness. The low species similarity between the two forests indicates that the floristic composition was quite distinct and that the mixture of primary forest and disturbed forest has led to an increase in total species diversity.     

Microeukaryotic diversity in the extreme environments of the Iberian Pyrite Belt: a comparison between universal and fungi-specific primer sets, temperature gradient gel electrophoresis and cloning

The Iberian Pyrite Belt extends from Portugal to Spain and is one of the most important pyrite regions in the world. Its aquatic reservoirs display extreme conditions characterized by low pH and high concentrations of heavy metals. In this study, the diversity of microeukaryotes was analysed at the abandoned mines of S?o Domingos (Portugal) and at Rio Tinto (Spain). DNA was extracted from water samples and a set of eukaryotic universal primers directed to the small subunit rRNA genes (rDNA) was used. The amplicons were analysed by molecular cloning and temperature gradient gel electrophoresis (TGGE). In addition, a fungi-specific primer set was also used in TGGE experiments. The fungi-specific primers contributed to a substantial increase in the number of fungal taxa found due, probably, to the relative low density of fungal structures. Several microorganisms, belonging (or closely related) to the ascomycetous yeast Pichia acaciae, the basidiomycetous yeasts Cryptococcus humicola and Cystofilobasidium bisporidii, the green algae Chlamydomonas noctigama and Chlorella protothecoides var. acidicola and some uncultured microeukaryotes were present at both localities, which suggests that specific microorganisms are adapted to the peculiar conditions of the Iberian Pyrite Belt extreme environments. However, in spite of the similarities, a higher algal richness was observed at S. Domingos, whereas for R. Tinto the richness of fungi was more prominent.