Abstract. Analyzing life history traits of butterfly communities and faunas frequently reveals a generalist-specialist continuum as the main gradient, where species using wide arrays of resources, with good dispersal ability and fast development are distinguished from those using specialised resources, having limited dispersal ability and developing slowly. To ascertain the validity of the generalistspecialist approach for an intermediately species-rich Central European fauna, we analyzed ten life history traits for 136 species of butterflies currently occurring in the Czech Republic, using principal correspondence analysis (PCA) and controlling for phylogeny. The main gradient extracted indeed revealed a generalist-specialist continuum, while the gradient perpendicular to the main axis distinguished between small-bodied polyvoltine species feeding on small herbaceous plants and large-bodied monovoltine species feeding on grasses or woody plants. We coin "constrained voltinism continuum" for the second gradient and argue that it reflects the effect of anti-herbivore strategies of larval host plants on butterfly development. The position of the butterflies in the PCA ordination mirrors the C-S-R (Competitors -Stress tolerators -Ruderals) strategies of their host plants. Butterflies that feed on C-and R-selected plants tend to be generalists, but differ in voltinism, whereas specialists tend to feed on S-selected plants. Regressing measures of current conservation status of individual species in the Czech Republic against the two extracted life history gradients yielded a significant but weak response for the generalist-specialist continuum and no response for the constrained voltinism continuum. The weak responses were due to a wide scatter of status measures among "mid generalists". The generalist-specialist continuum is hence a rather poor predictor of species conservation status. Species of high conservation concern are found either among specialists, or among mid generalists with low to intermediate values on the constrained voltinism axis.

a global database for metacommunity ecology, integrating species, traits, environment and space alienor Jeliazkov et al. #the use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across ecosystems, taxa and spatial scales. to address this gap, we collated 80 datasets from trait-based studies into a global database for metaCommunity Ecology: Species, Traits, Environment and Space; "CEStES". Each dataset includes four matrices: species community abundances or presences/absences across multiple sites, species trait information, environmental variables and spatial coordinates of the sampling sites. the CEStES database is a live database: it will be maintained and expanded in the future as new datasets become available. By its harmonized structure, and the diversity of ecosystem types, taxonomic groups, and spatial scales it covers, the CEStES database provides an important opportunity for synthetic trait-based research in community ecology. Background & SummaryA major challenge in ecology is to understand the processes underlying community assembly and biodiversity patterns across space 1,2 . Over the three last decades, trait-based research, by taking up this challenge, has drawn increasing interest 3 , in particular with the aim of predicting biodiversity response to environment. In community ecology, it has been equated to the 'Holy Grail' that would allow ecologists to approach the potential processes underlying metacommunity patterns 4-7 . In macroecology, it is common to study biodiversity variation through its taxonomic and functional facets along gradients of environmental drivers 8-10 . In biodiversity-ecosystem functioning research, trait-based diversity measures complement taxonomic ones to predict ecosystem functions 11 offering early-warning signs of ecosystem perturbation 12 .The topic of Trait-Environment Relationships (TER) has been extensively studied across the globe and across the tree of life. However, each study deals with a specific system, taxonomic group, and geographic region and uses different methods to assess the relationship between species traits and the environment. As a consequence, we do not know how generalizable apparent relationships are, nor how they vary across ecosystems, realms, and taxonomic groups. In addition, while there is an emerging synthesis about the role of traits for terrestrial plant communities 13,14 , we know much less about other groups and ecosystem types.To address these gaps, we introduce the CESTES database -a global database for metaCommunity Ecology: Species, Traits, Environment and Space. This database assembles 80 datasets from studies that analysed empirical multivariate trait-environment relationships between 1996 (the first...