Emasculation in orb web spiders has been a poorly understood phenomenon of sexual mutilation that has sometimes been assumed to represent maladaptive strategies. By reviewing all evidence including our original research from the past years, we showed that the eunuch phenomenon is adaptive. Namely, males engage in genital mutilation in order to become more agile and aggressive in fighting their rivals. Through emasculation, the males even secure remote copulation. These behaviours have co-evolved with extreme sexual size dimorphism as a response to sexual conflict.
COBISS.SI-ID: 37090861
Many organisms are sexually dimorphic, reflecting sex-specific selection pressures. But although sexual dimorphism may consist of different variables from size to shape and physiology, most research emphasizes a single aspect of sexual dimorphism, notably size. We dissected sexual dimorphism in spiders at two phylogenetic hierarchical levels. At the species level, we employed comparative phylogenetic tests to explore the association between sexual shape dimorphism (SShD) and sexual size dimorphism (SSD) in the orbweb clade Argiopinae. At the genus level, we then explored such patterns on a phylogeny of orb weavers (Araneoidea). While in argiopines we detected no clear association between SShD and SSD, we detected a significant correlation in all orb weavers at the genus level. The shape and the size components of sexual dimorphism may thus respond independently to selection pressures, but at certain phylogenetic levels SSD may be a prerequisite for SShD.
COBISS.SI-ID: 38237485
The article models vegetation on altitudinal gradient in the Galičica mountain range in Macedonia. Altitudinal gradient of turnover of forest communties was modelled by generalized additive mixed model (GAMM) procedure in R environment. Geomorphology, ecology, stuctural soil and htoptypes were taken as response variables. The most important were ecological variables, but also eco-evolutionary variables should be taken into consideraton, as they indicate a fairly quick response of plant species on genetic level already on ecological time scale.
COBISS.SI-ID: 39034157
Formalized classifications synthesizing vegetation data at the continental scale are being attempted only now, although they are of key importance for nature conservation planning. Therefore, we aim to provide a vegetation classification and to describe the main biogeographical patterns of floodplain forests and alder carrs in Europe. A database of more than 40 000 vegetation plots of floodplain forests and alder carrs across Europe was compiled. The main biogeographical patterns and environmentally-related gradients in species composition were determined using detrended correspondence and cluster analysis. Twenty-nine associations of floodplain forests and alder carrs were distinguished, which belong to four alliances: Alnion incanae, Osmundo-Alnion, Populion albae and Alnion glutinosae. This study is the first applying a formalized classification at the association level for a broad vegetation type at the continental scale. The proposed classification provides the scientific basis for the necessary improvement of the habitat classification systems used in European nature conservation.
COBISS.SI-ID: 39125293
The utility of DNA barcoding has been a subject of numerous debates in science. We explored the utility of DNA barcoding in identifying spider species that vary in taxonomic affiliation, morphological diagnosibility and geographic distribution. Our results generally point towards a high utility of DNA barcodes in identifying spider species. However, the size of the barcoding gap strongly depends on taxonomic groups and practices. Our results support models of independent patterns of morphological and molecular evolution by showing that DNA barcodes are effective in species identification regardless of their morphological diagnosibility. We also show that DNA barcodes represent an effective tool for identifying spider species over geographic scales, yet their variation contains useful biogeographic information.
COBISS.SI-ID: 38237229