the intestinal bacterial diversity of stichopus japonicus was investigated using 16s ribosomal rna gene (rdna) clone library and polymerase chain reaction/denaturing gradient gel electrophoresis (pcr-dgge). the clone library yielded a total of 188 clones, and these were sequenced and classified into 106 operational taxonomic units (otus) with sequence similarity ranging from 88 to 100%. the cov...

The intestinal microbiota compositions of 92 Japanese men were identified following consumption of identical meals for 3 days, and collected feces were analyzed through terminal restriction fragment length polymorphism. The obtained operational taxonomic units and smoking habits of subjects were analyzed by a data mining software. The constructed decision tree was able to identify explicitly th...

Taxonomy and species conservation are often assumed to be completely interdependent activities. However, a shortage of taxonomic information and skills, and confusion over where the limits to 'species' should be set, both cause problems for conservationists. There is no simple solution because species lists used for conservation planning (e.g. threatened species, species richness estimates, spe...

Explaining the structure of ecosystems is one of the great challenges of ecology. Simple models for food web structure aim at disentangling the complexity of ecological interaction networks and detect the main forces that are responsible for their shape. Trophic interactions are influenced by species traits, which in turn are largely determined by evolutionary history. Closely related species a...

Precision and reliability of barcode-based biodiversity assessment can be affected at several steps during acquisition and analysis of data. Identification of operational taxonomic units (OTUs) is one of the crucial steps in the process and can be accomplished using several different approaches, namely, alignment-based, probabilistic, tree-based and phylogeny-based. The number of identified seq...

A good definition of commensal microflora and an understanding of its relation to health are essential in preventing and combating disease. We hypothesized that the species richness of human oral microflora is underestimated. Saliva and supragingival plaque were sampled from 71 and 98 healthy adults, respectively. Amplicons from the V6 hypervariable region of the small-subunit ribosomal RNA gen...

Two very different systems of classification of the family Polemoniaceaeone a taxonomic system and the other a molecular cladistic system-have appeared recently. They are compared and reviewed. It is emphasized that taxonomy and cladistics use different basic systematic units (taxa or clades) and have different concepts of monophyly. Furthermore, taxonomy and molecular cladistics differ in the ...