European checkerspots (Melitaeini: Lepidoptera,Nymphalidae) are not aposematic – the point of view of great tits (Parus major)

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ONTOGENETIC NICHE SHIFT IN THE BRACHIOPOD TEREBRATALIA TRANSVERSA: RELATIONSHIP BETWEEN THE LOSS OF ROTATION ABILITY AND ALLOMETRIC GROWTH

Abstract: Many articulated brachiopods experience marked life habit variations during ontogeny because they experience their fluid environment at successively higher Reynolds numbers, and they can change the configuration of their inhalant and exhalant flows as body size increases. We show that the extant brachiopod Terebratalia transversa undergoes a substantial ontogenetic change in reorientation governed by rotation around the pedicle. T. transversa′s reorientation angle (maximum ability to rotate on the pedicle) decreases during ontogeny, from 180 degrees in juveniles to 10–20 degrees in individuals exceeding 5 mm, to complete cessation of rotation in individuals larger than 10 mm. Rotation ability is substantially reduced after T. transversa achieves the adult lophophore configuration and preferred orientation with respect to ambient water currents at a length of 2.5–5 mm. We hypothesize that the rotation angle of T. transversa is determined mainly by the position of ventral and dorsal points of attachment of dorsal pedicle muscles relative to the pedicle. T. transversa shows a close correlation between the ontogenetic change in reorientation angle and ontogeny of morphological traits that are related to points of attachment of dorsal pedicle muscles, although other morphological features can also limit rotation in the adult stage. The major morphological change in cardinalia shape and the observed reduction of rotation affect individuals 2.5–10 mm in length. The position of ventral insertions of dorsal pedicle muscles remains constant, but contraction of dorsal pedicle muscles is functionally handicapped because dorsal insertions shift away from the valve midline, rise above the dorsal valve floor, and become limited by a wide cardinal process early in ontogeny (<5 mm). The rate of increase of cardinal process width and of distance between dorsal pedicle muscle scars substantially decreases in the subadult stage (5–10 mm), and most of the cardinalia shell traits grow nearly isometrically in the adult stage (>10 mm). T. transversa attains smaller shell length in crevices than on exposed substrates. The proportion of small‐sized individuals and population density is lower on exposed substrates than in crevices, indicating higher juvenile mortality on substrates prone to grazing and physical disturbance. The loss of reorientation ability can be a consequence of morphological changes that strengthen substrate attachment and maximize protection against biotic or physical disturbance (1) by minimizing torques around the pedicle axis and/or (2) by shifting energy investments into attachment strength at the expense of the cost involved in reorientation.     

Changes in fatty acids contents and growth characteristics in transformed oilseed rape (Brassica napus)

Spring oilseed rapeBrassica napus L. ssp.oleifera cv. HM-81 was transformed with T_L-DNA of the Ri plasmid of the agropine strainAgrobacterium rhizogenes 15834. Selfed progenies (R₂ and R₃ generations) were studied for changes in values of growth characteristics and fatty acids contents. Transformants are ‘homozygous’ for T_L-DNA. Both generations of transformants differed significantly from the nontransformed control plants in reduced length, lower number of pods per plant, lower total mass of seeds and the higher number of branches. The contents of palmitic, linoleic and linolenic acids were significantly higher in transformants when compared with the control. On the contrary, the contents of both stearic and oleic acids were in most of transformants significantly lower. Only traces of erucic acid (less than 0.05 % ) were found, both in transformed and nontransformed plants.     

The carbohydrate-containing cell wall polymers of some species from the cluster "Streptomyces lavendulae"

The type strains of the cluster "Streptomyces lavendulae" species with a low level of DNA-DNA relatedness were found to contain different cell-wall carbohydrate polymers, whereas the species of this cluster with a level of DNA-DNA relatedness of about 60% contain similar or identical carbohydrate polymers. The type strains Streptomyces katrae VKM Ac-1220T and S. polychromogenes VKM Ac-1207T synthesize mannan with different amounts of alpha-1,2- and alpha-1,3-substituted mannopyranose units and a small number of 1,3-poly(glycerophosphate) chains. The cell walls of S. lavendulocolor VKM Ac-215T and Streptomyces sp. VKM Ac-2117 were found to contain a hitherto unknown teichuronic acid, whose repeating unit is a disaccharide consisting of diaminomannuronic acid and N-acetylgalactosamine:-->4)-beta-D-ManpNAc3NAcA-(1-->3)-alpha-D- GalpNAc-(1-->. In addition, the cell walls of these two streptomycetes contain beta-glucosylated 1,5-poly(ribitol phosphate). The cell walls of S. virginiae VKM Ac-1218T and S. flavotricini VKM Ac-1277T contain the same poly(glucosyl-glycerophosphate). The results presented in this paper are in accordance with the DNA-DNA relatedness data published earlier and indicate a taxonomic significance of the structure of the cell-wall polysaccharides for the delineation of pheneticall/related Streptomyces species.     

Diversity and ecology of algae from the Nahal Qishon river,northern Israel

In 59 samples of periphyton and phytoplankton collected in 2002 - 2003 from the Nahal Qishon (Qishon River), northern Israel, we found 178 species from seven divisions of algae and cyanoprocaryotes. Diatoms, clorophytes, and cyanoprocaryotes prevail. Nitzschia and Navicula (Bacillariophyta) are the most abundant. Most of the species are cosmopolitan or widespread, except Lagynion janei (Chrysophyta), which is endemic for the Mediterranean Realm. About 17% of species (26) are new for Israel and five of them represent the first recorded genera: Crinalium endophyticum Crow, Actinocyclus normanii (Gregory) Hustedt, Rhizoclonium hieroglyphicum (Agardh) Kütz (Chlorophyta), Lagynion janei Bourelly, and Stylococcus aureus Chodat. Most of them come from a rare riverine assemblage with red alga Audouinella pygmea, as well as from the estuarine assemblage. Alkaliphiles predominate among the indicators of acidity, with few acidophiles confined to the communities under the impact of industrial wastes. Among the indicators of salinity, most numerous are the oligohalobien-indifferents and species adapted to a moderate salinity level. The relative species richness of ecological groups and the indices of saprobity are correlated with changes in conductivity, pH, and N-nitrate concentration. Indicators of organic pollution fall in the range of betameso- to alfamesosaprobic self-purification grades. Our studies show ecological significance of the Nahal Qishon as a model for a strongly disturbed aquatic ecosystem in the coastal zone of eastern Mediterranean.     

I. P. Pavlov--a Full Member (Academician) of Russian Academy of Sciences (100-years anniversary)

I. P. Pavlov, the great Russian physiologist, the founder of a leading scientific school of physiology, first Russian scientist to be awarded the Nobel Prize. Pavlov's work received wide international recognition. He was elected full or honorary member of more than 120 academies, scientific societies and universities. In 1907 he was elected a Full Member (Academician) of Russian Academy of Sciences and headed the Physiological Laboratory of the Academy. In 1925, at his petition, the Laboratory was transformed into the Physiological Institute, remaining his head until 1936, when he had died. Since 1950 this is the Pavlov Institute of Physiology of the Russian Academy of Sciences.