James H. Oliver, Jr.’s Policy Forum “Crisis in biosystematics of arthropods” (20 May, p. 967) would have the scientific community do the right deed for the wrong reason. Systematics is not simply the identification of specimens, it is the reconstruction of evolutionary history; and it should be supported not just because it has practical applications (which it does) but because it is a fundamen...

the systematics, morphology, distribution, biology, economic importance and conservation of the spiny eel ( mastacembelus mastacembelus ) of iran are described, the species is illustrated, and a bibliography on this fish is provided. the single species is distributed in southern iranian basins, including karkheh, karun, jarrahi and helleh river basins, mostly part of the tigris river and persia...

the anamorphic fungus genus periconia is worldwide in distribution and causes foliar disease on plants mostly in tropical and subtropical regions. this study presents the description and illustration of p. palmivora discovered on leaves of phoenix dactylifera (palmae/arecaceae) from terai forest region of uttar pradesh, india. the taxonomic determination was based on morphological characteristi...

pollen morphology of some species of the genus malus (rosaceae) was investigatedtaxonomically. all species are characteristic by tricolpate pollens. exine sculpturing is variable but is mostlystriate. however, species may differ in degree of density of ridges and their orientation. the exine patterns inm. trilobata and m. florentina are very similar and were characterized by short and very bran...

the systematics, morphology, distribution, biology, economic importance and conservation of the bull shark ( carcharhinus leucas ) in iran are described, the species is illustrated, and a bibliography on this fish in iran is provided.

The broadly defined species of bacterial systematics frequently contain unnamed and unrecognized populations (ecotypes) differing in physiology, genome content, and ecology. Without formal recognition of such ecotypes, it is difficult for microbial ecologists to detect replacement of one ecotype by another in the face of global warming. The ecotype simulation algorithm has proved capable of sup...

We describe a method for computing the biases that systematic signals introduce in parameter estimation using a simple extension of the Fisher matrix formalism. This allows us to calculate the offset of the best fit parameters relative to the fiducial model, in addition to the usual statistical error ellipse. As an application, we study the impact that residual systematics in tomographic weak l...