Several comparative studies have previously identified breeding density and synchrony as potential determinants of reproductive success and extra-pair mating. However, the mechanisms and interaction of these two factors are poorly known. Here, we examined the effects of breeding density and synchrony on the behaviour, reproductive success and paternity losses in house sparrows. In order to test the effects of colony size, we created nest sites with varying numbers of nest-boxes. Our results show that there is an interaction between breeding synchrony and density, namely that breeding synchrony decreased with colony size. Neither colony size nor breeding synchrony seemed to influence brood size at fledging, although birds in larger colonies laid larger clutches. Moreover mate guarding behaviour was not influenced substantially by these two factors. Only nest guarding was significantly related to colony size and breeding synchrony. Paternity losses were not significantly related to colony size but they appeared to decrease with increasing synchrony. This finding supports the idea that extra-pair fertilisations are under male rather than female control.
This article deals with germanisms in Czech. Frequencies of 26 different new High German loanwords were analyzed in the Czech National Corpus. These borrowed words were standing in competition with their Czech synonyms. This comparison is used to study the question of whether germanisms or their equivalents in Czech are more used by native speakers. For this analysis new High German loanwords were deliberately selected in order to verify the actuality of the topic. But the major part of the study was examined in a diachronic period. This shows not only the current situation but in most cases the frequency of the selected loanwords throughout their existence. The calculations of the average frequency are made for each century (since 1650), and also in the recent modern period (from 1947 to 2008). and Článek se zabývá germanizmy v češtině. Prostřednictvím Českého národního korpusu byly zjišťovány různé frekvence 26 novohornoněmeckých výpůjček a jim konkurujících českých synonym. Článek se na základě frekvenčních srovnání snaží odpovědět na otázku, zda čeští rodilí mluvčí preferují germanizmy či dávají přednost jejich českým ekvivalentům. Článek analyzuje nejen aktuální situaci, ale ve většině případů ukazuje frekvenci vybraných germanizmů z diachronního hlediska, po celou dobu jejich existence. Byla vypočtena průměrná frekvence za každé století (od roku 1650), včetně posledního moderního období (od roku 1947 do roku 2008).
Climate change may facilitate shifts in the ranges and the spread of insect pests, but a warming climate may also affect herbivorous insects adversely if it disrupts the locally adapted synchrony between the phenology of insects and that of their host plant. The ability of a pest species to colonize new areas depends on its ability to adjust the timing of phenological events in its life cycle, particularly at high latitudes where there is marked seasonality in temperature and day length. Here we incubated eggs of three species of geometrid moth, Epirrita autumnata, Operophtera brumata and Erannis defoliaria from different geographical populations (E. autumnata and O. brumata from Northern Finland, E. autumnata and E. defoliaria from Southern Finland and all three species from Germany) in a climate chamber at a constant temperature to determine the relative importance of geographic origin in the timing of egg hatch measured in terms of cumulative temperature sums (degree days above 5°C, DD5); i.e. the relative importance of local adaptation versus phenotypic plasticity in the timing of egg hatch. In all three species, eggs from northern populations required a significantly lower temperature sum for hatching than eggs from southern populations, but the differences between them in temperature sum requirements varied considerably among species, with the differences being largest for the earliest hatching and northernmost species, E. autumnata, and smallest for the southern, late-hatching E. defoliaria. In addition, the difference in hatch timing between the E. autumnata eggs from Southern Finland and Germany was many times greater than the difference between the two Finnish populations of E. autumnata, despite the fact that the geographical distances between these populations is similar. We discuss how these differences in hatching time may be explained by the differences in hatch-budburst synchrony and its importance for different moth species and populations. We also briefly reflect on the significance of photoperiod, which is not affected by climate change. It is a controller that works parallel or in addition to temperature sum both for egg hatch in moths and bud burst of their host plants., Julia Fält-Nardmann, Tero Klemola, Mechthild Roth, Kai Ruohomäki, Kari Saikkonen., and Obsahuje bibliografii