85 research outputs found
Distance and habitat drive fine scale stingless bee (Hymenoptera: Apidae) community turnover across naturally heterogeneous forests in the western Amazon
High tree species richness in the western Amazon has been attributed to heterogeneous soils, which harbor edaphic specialist trees. While rapid transitions in tree communities are well documented across these variable soils few studies have investigated the role of habitat heterogeneity in structuring animal communities. Stingless bees are taxonomically diverse and important natural pollinators in Neotropical forests. However, little is known about their community structuring at local scales in naturally heterogeneous environments. We systematically sampled stingless bee communities found across three paired sites that included adjacent patches of white-sand and non-white-sand forest in the lowland Amazonian region of Loreto, Peru. We sought to understand: (1) How stingless bee species richness and abundance differs among white-sand and non-white-sand habitats and (2) The relative influence of fine scale geographic distance and habitat type in structuring stingless bee communities. We found that species richness did not differ between habitats and that species abundances were highest in white-sand habitats. Community analyses for sampling sites pooled across all months demonstrated that location and soil type played a significant role in structuring bee communities and that community turnover may be more strongly influenced by distance in white-sand habitats than non-white sand habitats. Our results suggest that distance and habitat play an important role in driving stingless bee community turnover at fine scales and that the interaction between habitat and geographic distance may promote higher stingless bee community turnover in white-sand habitats than non-white sand habitats
Chemovariation and antibacterial activity of extracts and isolated compounds from species of Ixora and Greenea (Ixoroideae, Rubiaceae)
Background A large number of secondary metabolites can be obtained from plants used for traditional medicine in two related genera (Ixora and Greenea) in the subfamily Ixoroideae (Rubiaceae), but there are only a few detailed studies on their bioactivities. Therefore, the main goals of this study were to determine the antibacterial activities of lipophilic extracts from plants of some Ixora and Greenea species native to Thailand, and to isolate some pure compounds from those extracts. Moreover, we compared the occurrence of compounds in different plant parts of samples from different habitats to better understand their variation. Methods A total of 56 lipophilic extracts were obtained from the leaves, stem bark, and root bark of eight Ixora and two Greenea species collected at various locations in Thailand. Isolated compounds were identified using nuclear magnetic resonance. Antimicrobial activities were evaluated against four Gram-positive and nine Gram-negative human pathogenic bacterial strains. Results Extracts from I. javanica, I. nigricans, I. brunonis, and G. montana, along with isolated scopoletin, exhibited antibacterial activities against Gram-positive methicillin-resistant Staphylococcus aureus ATCC 43300, with minimum inhibitory concentration values ranging from 64 to 256 µg/mL. The occurrence of scopoletin, isofraxidin, and geniposidic acid in lipophilic extracts showed some variation among different plant parts and species. Conclusions Lipophilic extracts of Ixora and Greenea species have the potential to be developed as anti-Gram-positive agents, in particular to counter infections of methicillin-resistant S. aureus strains. The chemical profiles showed differences between floristic regions but similarity within the same plant parts
On the diversity and richness of understory bryophytes at Nectandra Cloud Forest Reserve, Costa Rica
A survey of the understory bryophytes in the Nectandra Cloud Forest Preserve yielded 1083 specimens distributed among 55 families, represented by 74 genera of mosses, 75 genera of liverworts and 3 of hornworts. We studied and analyzed the bryophytic distribution on six types of substrates: 1) corticolous, 2) epiphyllous, 3) saxicolous, 4) terricolous, 5) aquatic and 6) lignicolous. The richness and composition of bryophyte genera are compared to those of other previous bryophyte surveys from 4 other sites with different oceanic exposures, climatic and geographic conditions in Costa Rica
Impact of changing climate on bryophyte contributions to terrestrial water, carbon, and nitrogen cycles
Bryophytes, including the lineages of mosses, liverworts, and hornworts, are the second-largest photoautotroph group on Earth. Recent work across terrestrial ecosystems has highlighted how bryophytes retain and control water, fix substantial amounts of carbon (C), and contribute to nitrogen (N) cycles in forests (boreal, temperate, and tropical), tundra, peatlands, grasslands, and deserts. Understanding how changing climate affects bryophyte contributions to global cycles in different ecosystems is of primary importance. However, because of their small physical size, bryophytes have been largely ignored in research on water, C, and N cycles at global scales. Here, we review the literature on how bryophytes influence global biogeochemical cycles, and we highlight that while some aspects of global change represent critical tipping points for survival, bryophytes may also buffer many ecosystems from change due to their capacity for water, C, and N uptake and storage. However, as the thresholds of resistance of bryophytes to temperature and precipitation regime changes are mostly unknown, it is challenging to predict how long this buffering capacity will remain functional. Furthermore, as ecosystems shift their global distribution in response to changing climate, the size of different bryophyte-influenced biomes will change, resulting in shifts in the magnitude of bryophyte impacts on global ecosystem functions
Finding needles in haystacks: linking scientific names, reference specimens and molecular data for Fungi
DNA phylogenetic comparisons have shown that morphology-based species recognition often underestimates fungal diversity. Therefore, the need for accurate DNA sequence data, tied to both correct taxonomic names and clearly annotated specimen data, has never been greater. Furthermore, the growing number of molecular ecology and microbiome projects using high-throughput sequencing require fast and effective methods for en masse species assignments. In this article, we focus on selecting and re-annotating a set of marker reference sequences that represent each currently accepted order of Fungi. The particular focus is on sequences from the internal transcribed spacer region in the nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Re-annotated and verified sequences were deposited in a curated public database at the National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci (RTL) database, and will be visible during routine sequence similarity searches with NR_prefixed accession numbers. A set of standards and protocols is proposed to improve the data quality of new sequences, and we suggest how type and other reference sequences can be used to improve identification of Fungi
Finding needles in haystacks:Linking scientific names, reference specimens and molecular data for Fungi
DNA phylogenetic comparisons have shown that morphology-based species recognition
often underestimates fungal diversity. Therefore, the need for accurate DNA sequence
data, tied to both correct taxonomic names and clearly annotated specimen data, has
never been greater. Furthermore, the growing number of molecular ecology and microbiome
projects using high-throughput sequencing require fast and effective methods for
en masse species assignments. In this article, we focus on selecting and re-annotating a
set of marker reference sequences that represent each currently accepted order of Fungi.
The particular focus is on sequences from the internal transcribed spacer region in the
nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Reannotated
and verified sequences were deposited in a curated public database at the
National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci
(RTL) database, and will be visible during routine sequence similarity searches with
NR_prefixed accession numbers. A set of standards and protocols is proposed to improve
the data quality of new sequences, and we suggest how type and other reference
sequences can be used to improve identification of Fungi.The Intramural Research Programs
of the National Center for Biotechnology Information, National
Library of Medicine and the National Human Genome Research
Institute, both at the National Institutes of Health.http://www.ncbi.nlm.nih.gov/bioproject/PRJNA177353am201
Finding needles in haystacks: Linking scientific names, reference specimens and molecular data for Fungi
DNA phylogenetic comparisons have shown that morphology-based species recognition
often underestimates fungal diversity. Therefore, the need for accurate DNA sequence
data, tied to both correct taxonomic names and clearly annotated specimen data, has
never been greater. Furthermore, the growing number of molecular ecology and microbiome
projects using high-throughput sequencing require fast and effective methods for
en masse species assignments. In this article, we focus on selecting and re-annotating a
set of marker reference sequences that represent each currently accepted order of Fungi.
The particular focus is on sequences from the internal transcribed spacer region in the
nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Reannotated
and verified sequences were deposited in a curated public database at the
National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci
(RTL) database, and will be visible during routine sequence similarity searches with
NR_prefixed accession numbers. A set of standards and protocols is proposed to improve
the data quality of new sequences, and we suggest how type and other reference
sequences can be used to improve identification of Fungi.B.R. and C.L.S. acknowledge support from the Intramural Research
Program of the National Institutes of Health, National Library of
MedicinePeer Reviewe
Finding needles in haystacks : linking scientific names, reference specimens and molecular data for Fungi
DNA phylogenetic comparisons have shown that morphology-based species recognition
often underestimates fungal diversity. Therefore, the need for accurate DNA sequence
data, tied to both correct taxonomic names and clearly annotated specimen data, has
never been greater. Furthermore, the growing number of molecular ecology and microbiome
projects using high-throughput sequencing require fast and effective methods for
en masse species assignments. In this article, we focus on selecting and re-annotating a
set of marker reference sequences that represent each currently accepted order of Fungi.
The particular focus is on sequences from the internal transcribed spacer region in the
nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Reannotated
and verified sequences were deposited in a curated public database at the
National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci
(RTL) database, and will be visible during routine sequence similarity searches with
NR_prefixed accession numbers. A set of standards and protocols is proposed to improve
the data quality of new sequences, and we suggest how type and other reference
sequences can be used to improve identification of Fungi.The Intramural Research Programs
of the National Center for Biotechnology Information, National
Library of Medicine and the National Human Genome Research
Institute, both at the National Institutes of Health.http://www.ncbi.nlm.nih.gov/bioproject/PRJNA177353am201
Recommended from our members
Adaptive Traits and Community Assembly of Epiphyllous Bryophytes
Leaf surfaces of tropical vascular plants provide homes for diverse groups of organisms, including epiphyllous (leaf-colonizing) bryophytes. Each leaf harbors a temporally and spatially discrete community of organisms, providing an excellent system for answering some of the most fundamental questions in ecology and evolution. In this dissertation, I investigated two main aspects of epiphyllous bryophyte biology: 1) adaptive traits of bryophytes to living on the leaf surface, and 2) community assembly of epiphyllous bryophytes in space (between-hosts) and time (succession).For the first part, I used published trait data and phylogeny of liverworts in family Lejeuneaceae to demonstrate that only the production of asexual propagules appeared to evolve in response to living on the leaf surface, while other hypothesized traits did not have correlated evolution with epiphylly. The second portion dealt with the assembly of communities among different host types. In this part, I identified communities of epiphyllous bryophytes from the same set of three hosts across the gradient of water deficit fluctuation, as represented by the daily range of vapor pressure deficit (VPD) on the island Moorea, French Polynesia. Dissimilarity of epiphyllous communities among host types (beta diversity) increased with the increasing VPD range, suggesting that assembly of bryophyte community may depend on microclimate fluctuation. In the last portion of this dissertation, I investigated temporal changes of epiphyllous communities on Inocarpus fagifer, using chronosequence and long-term observation of tagged leaves in the field. Data from both approaches showed significant changes in abundance, species richness, and composition over time. These successional changes, however, did not follow any single trajectory, resulting in divergent communities among leaves of older age. Together, the results from this dissertation work improve our understanding of fundamental biology of epiphyllous bryophytes and allow future researchers to use this system to answer broader questions in ecology and evolution
Recommended from our members
Adaptive Traits and Community Assembly of Epiphyllous Bryophytes
Leaf surfaces of tropical vascular plants provide homes for diverse groups of organisms, including epiphyllous (leaf-colonizing) bryophytes. Each leaf harbors a temporally and spatially discrete community of organisms, providing an excellent system for answering some of the most fundamental questions in ecology and evolution. In this dissertation, I investigated two main aspects of epiphyllous bryophyte biology: 1) adaptive traits of bryophytes to living on the leaf surface, and 2) community assembly of epiphyllous bryophytes in space (between-hosts) and time (succession).For the first part, I used published trait data and phylogeny of liverworts in family Lejeuneaceae to demonstrate that only the production of asexual propagules appeared to evolve in response to living on the leaf surface, while other hypothesized traits did not have correlated evolution with epiphylly. The second portion dealt with the assembly of communities among different host types. In this part, I identified communities of epiphyllous bryophytes from the same set of three hosts across the gradient of water deficit fluctuation, as represented by the daily range of vapor pressure deficit (VPD) on the island Moorea, French Polynesia. Dissimilarity of epiphyllous communities among host types (beta diversity) increased with the increasing VPD range, suggesting that assembly of bryophyte community may depend on microclimate fluctuation. In the last portion of this dissertation, I investigated temporal changes of epiphyllous communities on Inocarpus fagifer, using chronosequence and long-term observation of tagged leaves in the field. Data from both approaches showed significant changes in abundance, species richness, and composition over time. These successional changes, however, did not follow any single trajectory, resulting in divergent communities among leaves of older age. Together, the results from this dissertation work improve our understanding of fundamental biology of epiphyllous bryophytes and allow future researchers to use this system to answer broader questions in ecology and evolution
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