Polymorphisms are widely known in allozymes and are often assumed neutral in the context of phylogenetic and population genetic analyses. However, several studies revealed that, in some loci and species, selection is strongly acting on allozymes and that temperature seems to be an important selective agent. Therefore, we individually determined the recovery time from chill-coma and heat knock-down time of 542 individuals of P. coridon sampled at four sites. Afterwards, we analyzed patterns of allozyme variations in these butterflies by allozyme electrophoresis of eleven loci to test the enzymes' performance under thermal stress conditions and to investigate the possibility of adaptive genotypic variation in relation to temperature stress resistance traits. We obtained significant differences of reactions to cold and heat shocks between the sexes and between reared and wild-captured individuals, but no significant differences among genotypes were found for most of the investigated allozyme loci. However, the Aat1 locus showed significant differences between different genotypes in chill-coma recovery times (p < 0.001), and marginal differences in heat knock-down times (p = 0.073). Thus, Aat1 might be a target for thermal selection. Consequently, our results revealed no clear influence of temperature on most allozyme loci and the otherwise observed differentiation in P. coridon might be explained by stochasticity, and thus geographic structuring should reflect biogeographic processes.

The Eurasian badger (Meles meles) and the red fox (Vulpes vulpes) are the two most widespread medium-sized carnivores in Hungary. We hypothesise that niche segregation between these species may be observed in the selection of burrow sites. Burrowsite selection was investigated by evaluating habitat preferences for three habitat categories (forest covered, open and mixed). Differences between overall habitat selection by the two species within the study areas were not significant, but the area ratios of habitat categories within the immediate surroundings (400 m) of burrows were significantly different. Around the red fox burrows, the ratios of mixed habitats and small-mammal hole densities were significantly higher (p < 0.001 and p = 0.007, respectively) than around those of the Eurasian badger. This led us to conclude that the red fox, due to its diet, may select sites rich in small mammals, which is manifested in the preference and use of mixed habitats.

Seasonality in the immune defence of invertebrates can coincide with environmental variation but whether it is endogenously regulated, via biological clocks, or affected by previous immune challenges remains unclear. Using the native noble crayfish (Astacus astacus) held under constant laboratory conditions for a year, we explored (1) potential endogenous seasonal variation in immune defence, i.e. the encapsulation response, (2) the potential positive effect of repeated challenges with a standardized immune insult in subsequent seasons, i.e. long-lasting immune priming, and (3) whether long-lasting immune priming is dependent on endogenous seasonality. Independent measurements of the encapsulation response in different seasons revealed significant variation and a decrease in autumn. This result indicates previously undetected endogenous seasonal variation in invertebrate immunity. The weaker immune defence observed in autumn, i.e. the reproductive season of crayfish, might be caused by a circannual clock. When corrected for endogenous seasonality, we found no evidence for long-lasting immune priming.

Assessing the origin of trait variation during evolutionary history is an important first step in understanding evolutionary diversification. Here, we tested the influence of shared ancestry and climate, and the interplay of both, on the variation of ten life history traits in Triturus newts. We showed that (1) climate alone has driven the evolution of variation in five life history traits, (2) phylogenetic signal partly explains the variation in two traits (vitellus diameter and snout—vent length of larvae at metamorphosis), and (3) the interplay of shared ancestry and climate explains the variation in one trait (snout—vent length of larvae at metamorphosis). This study highlights the coarse-grained influence of shared ancestry and climate on the structure of phenotypic trait variation in Triturus and provides a handle for more detailed, fine grained studies on the evolution of phenotypic trait variation.

Indicator species have been proposed to be used for revealing common status of ecosystems and their biodiversity. We studied breeding forest birds in southern Finland. Our aim was to find bird species combinations that would predict species richness of forest bird assemblages at several spatial scales. We evaluated statistical models that included 1–5 indicator candidate species, and ranked them according to the Bayesian information criterion. The red-breasted flycatcher Ficedula parva, the pygmy owl Glaucidium passerinum and the three-toed woodpecker Picoides tridactylus were found to be the best multiscale indicators. Models at smaller spatial scales, including several indicator species better explained the total variation in species richness. The indicators mostly revealed properties of the forest site rather than variation in species richness caused by species interactions. Our results show that a suitable set of indicator species may be a useful and quick method for the evaluation of bird diversity in forest environments.