EVOLUTION OF MIMICRY PATTERNS IN METRIORRHYNCHUS (COLEOPTERA: LYCIDAE): THE HISTORY OF DISPERSAL AND SPECIATION IN SOUTHEAST ASIA

The concept of Müllerian mimicry suggests convergent evolution to an intermediate pattern and does not predict polymorphism in mimicry rings. We examined the evolution of mimicry patterns and the order of divergence of various factors, including the role of aposematic patterns in speciation, in a clade of net-winged beetles with a robust phylogeny that suggests that they dispersed from the Australian to Asian plate. We found strong evidence for the evolution of mimicry via advergence in Metriorrhynchus because older patterns are represented in the Oriental region within more than 100 species of lycids from several lineages. Advergence was likely the cause of the observed intraspecific polymorphism in contrast to the predicted universal monomorphism. Polymorphism was found in populations of two species in Sumatra and Borneo and in populations fine-tuned to subtle variants in various habitats. The advergence is likely to be based on the small population sizes of immigrants. The differences in population sizes result in much higher benefits for dispersing species than native populations. Speciation was trigged by the divergence in aposematic coloration, and the genetic differences accumulated slowly during incomplete isolation. We assumed that the differentiation in genitalia through sexual selection ultimately reinforced speciation initiated by the shift between mimicry patterns.     

Influence of tourism on dwarf pine (Pinus mugo) communities in the Vysoké Tatry Mountains

The attention was focussed on the evaluation of the impact of trampling on autochtonous dwarf pine communities in the Tatra National Park (Vysoké Tatry Mts.). Use was made of combined phytocoenological and production-ecological methods. Results are described and discussed according to floristic-phytocoenological analyses, production-ecological analyses and the basic parameters of total organic matter supply.     

Sex-linked,androgen-dependent differences in renal retention of trimethylselenonium ions

The metabolism of trimethylselenonium ions (TMSe) was studied in male and female rats during maturation. Selenium (Se) retention in the whole body as well as in organs was found to be significantly higher in male rats than in female a few hours after parenteral administration of TMSe. The pronounced Se accumulation was observed in male kidneys. This sex-linked difference was dependent on the presence of gonades and started to be manifested with sexual maturation during the third decade of postnatal life. The effects of steroid hormones on the retention of Se from TMSe were examined in female and castrated male rats. The results indicate that TMSe metabolism in rat kidneys may be influenced by androgen steroids.     

Syntaxonomy of the Onopordum acanthium communities in temperate and continental Europe

Ruderal communities dominated by Onopordum acanthium are encountered in those regions of Europe with a dry and continental climate. Variability in the climate and local phytogeography within these regions is reflected in the floristic variability of the communities studied. A floristic cline within the communities was summarised by means of multivariate classification and ordination methods. Two associations distributed in temperate Europe and belonging to the Onopordetalia, the Onopordetum acanthii s.str. and Carduo acanthoidis-Onopordetum acanthii, were distinguished; The Carduo acanthoidis-Onopordetum is varied and occurs in several geographic races and sub-races. The Onopordetum acanthii s.str. is confined to deep inner-montane valleys with a continental climate. The other Onopordum acanthium communities described from Spain belong to the Scolymo hispanici-Onopordetalia nervosi.Abbreviations CA = correspondence analysis - CLC = complete linkage clustering     

Some notes on the terminology of brassinosteroids

In this paper the definitions of brassinolide, brassinolide activity andbrassins are reviewed, and definitions for the terms brassin, naturalbrassinosteroids and brassinosteroid analogues, based on biosynthetic reasoningand structure similarity are proposed.