nvestigating the function of both male and female mating behaviours is essential in our attempts to understand the evolution of mating systems. Variation in mating behaviours among different populations within a species provides a useful opportunity to explore how behaviours may co-vary, although comparative studies are still rather few in number. Population variation in mating behaviour may also have important implications in terms of the evolution of reproductive isolation, the distribution of genetic diversity within and between populations, and the associated ability of those populations to adapt. Here we consider male and female mating behaviour in two populations of the two-spot ladybird, Adalia bipunctata, from the UK and Russia. We find that male and female mating behaviours differ between the populations in terms of the length of female rejection behaviour and the duration of mating, and that this variation is independent of which population an individual's mating partner is from. Our data confirm that patterns of sexual selection and reproductive behaviour are likely to vary across populations in the two-spot ladybird. The extent to which this variation is due to current ecological factors or population history remains to be verified for this species, as for many others., Penelope R. Haddrill, Michael E.N. Majerus, David M. Shuker., and Obsahuje seznam literatury
To rank variables affecting risk of human disease due to tick-borne encephalitis (TBE) virus in the Russian Far East, we compared annual changes in ( 1 ) frequency of human contact with vector ticks, (2) prevalence of infection in the tick population and (3) quantity of virus present infected ticks. Sites were sampled uniformly over a 4-year period in a forested region where Ixodes persulcatus serves as the principle vector. The questing density of ticks on vegetation remained relatively constant during the course of this study. The frequency of contacts of the local human population with ticks carrying different doses of the TBE virus was changeable. The rate of TBE infection of humans in the study site corresponded to that of human contacts with highly infected ticks. The density of highly infected ticks represents the principal parameter for determining potential epidemiological significance of a natural TBE focus.
The occurrence of colour polymorphism in wild populations of the necrophagous fly Prochyliza nigrimana (Diptera: Piophilidae) is recorded but never treated in detail. The present paper shows that there is a seasonal distribution in the morphotypes, with the dark morphs emerging in spring and pale morphs emerging later and most abundant in summer. Furthermore, different proportions of each morph occur along altitudinal gradients, with dark morphs significantly more abundant at low altitudes, where mean temperatures are warmer than at high altitudes where the pale coloured morphs were more abundant. Explanations based on the adaptive value of thermal melanism are discussed. and Daniel Martín-Vega, Arturo Baz.
At the southern limit of its range the endangered butterfly Coenonympha oedippus inhabits grasslands (wet, dry) that differ significantly in the abundance of its larval hostplants (wet > dry) and mean annual air temperature (wet < dry). We determined the difference in the wing morphology of individuals in the two contrasting habitats to test whether and how traits associated with wing size, shape and eye like spots vary in the sexes and two ecotypes. We show that sexual dimorphism follows the same (wing size and shape, number of eyespots on forewing) or different (relative area of eyespots on hindwings) patterns in the two contrasting habitats. Irrespective of ecotype, females had larger, longer and narrower wings, and more forewing eyespots than males. Sexual dimorphism in the relative area of eyespots on hindwing was female-biased in the wet, but male-biased in the dry ecotype. Ecotype dimorphism in wing size and the relative area of eyespots on the hindwing is best explained by mean annual air temperature and abundance of host-plants. While ecotype dimorphism in wing size did not differ between sexes, neither in direction (wet > dry) or in degree, in the two sexes the relative area of eyespots on hindwing had opposite patterns (males: dry > wet; females: wet > dry) and was more pronounced in males than in females. The differences in wing shape between ecotypes were detected only in the hindwings of males, with more rounded apex in the dry than in the wet ecotype. We discuss the life-history traits, behavioural strategies and selection mechanisms, which largely account for the sex- and ecotype-specific variation in wing morphology., Jure Jugovic, Sara Zupan, Elena Bužan, Tatjana Čelik., and Obsahuje bibliografii
In the present study changes of some blood parameters of wild female yellowfin seabream (Acanthopagrus latus) caught from Persian Gulf were assayed during reproductive cycle. Altogether, 120 female A. latus (15 each month) were captured monthly from October 2010 to May 2011 from the Mussa Creek in the north-west of Persian Gulf. Blood samples were collected from caudal vein; plasma was separated and kept at –80 °C till analysis. Total protein, glucose, cholesterol, triglyceride, electrolytes, calcium, sodium, chloride, magnesium, potassium plus hepatic enzymes, Alanine Amino Transferase (ALT) and Aspartate Amino Transferase (AST), were assayed in plasma sample. Total protein and calcium increased parallel to ovarian development and decreased after spawning time. Cholesterol and triglyceride had a peak during vitellogenesis and decreased after spawning but glucose had a peak during spawning time. Most of the electrolytes (sodium, magnesium and potassium) did not show any significant changes during the reproductive cycle in A. Latus. AST reached a peak during final
maturation of ovaries but ALT did not show any significant difference during differentsampling times.Our findings showed that biochemical parameters could be used as indicators of physiological status during differentmaturation stage in this species.
Thermal requirements for flight in butterflies is determined by a combination of external factors, behaviour and physical constraints. Thorax temperature of 152 butterflies was monitored with an infra-red thermometer in controlled laboratory conditions. The temperature at take-off varied from 13.4°C, for a female Heteronympha merope to 46.3°C, for a female Junonia villida. Heteronympha merope, an understorey species, had the lowest recorded take-off temperatures, with females flying at a much lower thorax temperatures than males. Among the tested butterfly species, warming-up rate was positively correlated with take-off temperature and negatively with body mass. Wing loading is a major variable in determining the thorax flight temperature. Butterflies with the highest wing-loadings experienced the highest thorax temperatures at take-off. A notable exception to this rule is Trapezites symmomus, the only Hesperiidae of our data set, which had thorax flight temperatures of 31.5°C and 34.5°C, well within the range of the observed butterflies, despite a wing load ca. five times higher. The high thorax temperature recorded in J. villida is probably linked to its high flight speed. The results highlight the importance of physical constraints such as body size on the thermal requirements for flight across a range of butterfly species., Gabriel Nève, Casey Hall., and Obsahuje bibliografii
Genetic variation for thermal plasticity plays an important role in the success or failure of a species with respect to the colonization of different thermal habitats and the ability to deal with climatic change. The aim of this paper is to study the relative contribution of the additive and non-additive components of genetic variation for the slope of the temperature reaction norm for juvenile growth rate in the springtail Orchesella cincta. We present the outcome of an artificial selection experiment for steep and flat temperature reaction norms and the results of a parent-offspring heritability experiment. There was a considerable phenotypic variation for the slope of the reaction norm. The selection experiment and the offspring to parent regression analysis, however, yielded no evidence for significant additive genetic variance. There were also no indications for maternal effects. The full-sib analysis, on the other hand, revealed a significant broad sense heritability of 0.76. An unforeseen result was that the slopes of females were steeper than those of males. This influenced the broad sense heritability of the full-sib analysis, since accidental female or male biased broods inflate the estimate of heritability. A randomization test showed that the probability level of the observed "between group" variance on the basis of the sexual differences alone was less than 10-5. From this we conclude that autosomal genetic variation played its own separate role. In conclusion, the thermal reaction norm for growth in juvenile O. cincta is not very much determined by the additive effects of a large number of independent genes, but more likely based on a still unknown but mainly non-additive, partially sex-related genetic mechanism, possibly including both dominance and epistatic effects. Hypotheses about the role of phenotypic plasticity in processes of local adaptation and speciation should thus be alert to such a complex genetic architecture.
There exists a rich literature on systems of connections and systems of vector fields, stimulated by the irimportance in geometry and physis. In the previous papers [T1], [T2] we examined a simple type of systems of vector fields, called parameter dependent vector fields, and established their varionational equation.
In this paper we generalize the above equation to the projectable system of vector fields. The material is organized as follows: in the first section the geometry of the product bundle is presented. In the second we introduce the notion of derivative along a direction and prove Theorem 1. The third section is devoted to Theorem
2, which represents the main result of the paper. Some examples are presented in the last section. In a further paper we will apply the results in order to investigate some special systems as strong systems, “nice” systems and systems of connections generated by systems of vector fields.
We study the integrability of Banach space valued strongly measurable functions defined on [0, 1]. In the case of functions f given by ∑ ∞ n=1 xnχEn , where xn are points of a Banach space and the sets En are Lebesgue measurable and pairwise disjoint subsets of [0, 1], there are well known characterizations for Bochner and Pettis integrability of f. The function f is Bochner integrable if and only if the series ∑∞ n=1 xn|En| is absolutely convergent. Unconditional convergence of the series is equivalent to Pettis integrability of f. In this paper we give some conditions for variational Henstock integrability of a certain class of such functions.