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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2009.01.030 Byline: Csaba Moskat (a), Mark E. Hauber (b), Jesus M. Aviles (c), Miklos Ban (d), Rita Hargitai (e)(f), Marcel Honza (g) Abstract: In birds, multiple parasitism is the laying of two or more eggs by one or more parasitic females in a single host nest. Several cognitive mechanisms may explain how multiple parasitism could affect parasite egg discrimination by hosts. Rejection based on discordance predicts that multiple parasitism provides a perceptually more error-prone way for hosts to reject parasitism because more foreign eggs decrease the chance that any one egg is perceived as most dissimilar and recognized as foreign, unless parasite eggs are all similarly highly nonmimetic. In contrast, rejection based on clutch uniformity predicts that in multiple parasitism egg rejection is more error-proof if mimicry by parasite eggs is variable, because increased variation in egg appearance makes for easier egg rejection for hosts. Finally, true egg recognition, that is, rejection based on memory of the host's own eggs, predicts no differences in rejection rates from nests with single or multiple parasitism. We studied common cuckoos, Cuculus canorus, parasitizing a population of great reed warblers, Acrocephalus arundinaceus, in Hungary where multiple parasitism was frequent. Hosts rejected parasite eggs less often in nests with multiple parasitism than in nests with single parasitism. These observations were confirmed by experimental parasitism and support the rejection based on discordance hypothesis. As hosts were more likely to tolerate cuckoo eggs in nests with multiple parasitism, we found that multiple parasitism more than doubled cuckoos' reproductive output per host nest compared to single parasitism. Author Affiliation: (a) Animal Ecology Research Group of the Hungarian Academy of Sciences, Budapest, Hungary (b) Department of Psychology, Hunter College, City University of New York, U.S.A. (c) Departamento de Biologia Animal y Ecologia, Universidad de Granada, Spain (d) Behavioural Ecology Research Group, Department of Evolutionary Zoology, University of Debrecen, Hungary (e) Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eotvos Lorand University, Budapest, Hungary (f) Institute of Environmental Sciences, College of Nyiregyhaza, Hungary (g) Institute of Vertebrate Biology, Academy of Science of the Czech Republic, Brno, Czech Republic Article History: Received 15 May 2008; Revised 18 June 2008; Accepted 26 January 2009 Article Note: (miscellaneous) MS. number: 08-00313R

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2007.08.009 Byline: Gergely Hegyi, Balazs Rosivall, Eszter SzollAsi, Rita Hargitai, Marcel Eens, Janos Torok Abstract: Explaining sexual ornamentation in the limiting sex, usually females, requires information on the proximate background of ornaments and their consequences for sexual selection. Phenotypic variation within individuals has received little attention in either of these research directions. We used 6 years of data to examine the information content and potential role of white wing patch size in female collared flycatchers, Ficedula albicollis. Female wing patch size differed among years. Yearling females had smaller wing patches than older females. The negative effect of original patch size on intraindividual patch size change was stronger in yearling than in older birds, which may reflect an age-dependent trade-off. Change in wing patch size was strongly positively related to the summer North Atlantic Oscillation (NAO) index. Clutch size laid in the previous breeding season had a negative effect on patch size change, but only in high-NAO years. Thus, the immediate effect of poor climate during moult apparently overrode the more indirect influence of reproductive effort. Two sexually selected ornaments of mates were unrelated to female wing patch size at the population level, but intraindividual changes of female wing patch size significantly predicted differences in wing patch size between mates obtained in the 2 years. Our data suggest that significant mating advantages to more ornamented females may not be detected from population-level mating patterns. Research on potential female ornaments should also pay more attention to age-dependent phenotypic plasticity, the trade-off between current and future ornament size and the costs of reproduction to apparent future attractiveness. Author Affiliation: (a) Behavioural Ecology Group, Department of Systematic Zoology and Ecology, Eotvos Lorand University, Hungary (a ) Department of Biology, University of Antwerp, Belgium Article History: Received 10 January 2007; Revised 16 February 2007; Accepted 27 August 2007 Article Note: (miscellaneous) MS. number: 9230R

Abstract Endocrine disrupting chemicals (EDCs) include a wide array of pollutants, such as some metals and other toxic elements, which may cause changes in hormonal homeostasis. In addition to affecting physiology of individuals directly, EDCs may alter the transfer of maternal hormones to offspring, i.e. causing transgenerational endocrine disruption. However, such effects have been rarely studied, especially in wild populations. We studied the associations between environmental elemental pollution (As, Cd, Cu, Ni, Pb) and maternally-derived egg thyroid hormones (THs) as well as nestling THs in great tits (Parus major) using extensive sampling of four pairs of polluted and reference populations across Europe (Finland, Belgium, Hungary, Portugal). Previous studies in these populations showed that breeding success, nestling growth and adult and nestling physiology were altered in polluted zones compared to reference zones. We sampled non-incubated eggs to measure maternally-derived egg THs, measured nestling plasma THs and used nestling faeces for assessing local elemental exposure. We also studied whether the effect of elemental pollution on endocrine traits is dependent on calcium (Ca) availability (faecal Ca as a proxy) as low Ca increases toxicity of some elements. Birds in the polluted zones were exposed to markedly higher levels of toxic elements than in reference zones at the populations in Finland, Belgium and Hungary. In contrast to our predictions, we did not find any associations between overall elemental pollution, or individual element concentrations and egg TH and nestling plasma TH levels. However, we found some indication that the effect of metals (Cd and Cu) on egg THs is dependent on Ca availability. In summary, our results suggest that elemental pollution at the studied populations is unlikely to cause overall TH disruption and affect breeding via altered egg or nestling TH levels with the current elemental pollution loads. Associations with Ca availability should be further studied. Graphical abstract Image 1 Highlights • We studied element-associated transgenerational endocrine disruption in wild populations. • We sampled four pairs of metal-polluted and reference sites across Europe. • Eggs and nestling plasma of Parus major were analysed for thyroid hormones and nestling faeces for toxic elements. • We found no general association between toxic element exposure, egg and nestling plasma thyroid hormones. • The effect of cadmium and copper on egg thyroid hormones depended on calcium availability. [ABSTRACT FROM AUTHOR]

In an urban environment, birds are exposed to metals, which may accumulate in their tissues and cause oxidative stress. Female birds may eliminate these pollutants through depositing them into eggs, thus eggs become suitable bioindicators of pollution. In this study, we aimed to analyse whether eggshell spotting pattern, egg volume, eggshell thickness and egg yolk antioxidant (lutein, tocopherol, retinol and selenium) levels were related to the breeding area (woodland versus urban) and the metal levels in the eggshell of a small passerine species, the great tit ( Parus major ). In the urban habitat, soil and eggshells contained higher concentrations of metals, and soil calcium level was also higher than that in the woodland. Eggshell spotting intensity and egg volume did not differ between eggs laid in the woodland and the urban park, and these traits were not related to the metal levels of the eggshell, suggesting that these egg characteristics are not sensitive indicators of metal pollution. A more aggregated eggshell spotting distribution indicated a higher Cu concentration of the eggshell. We found that eggshells were thinner in the less polluted woodland habitat, which is likely due to the limited Ca availability of the woodland area. Great tit eggs laid in the urban environment had lower yolk lutein, retinol and selenium concentrations, however, as a possible compensation for these lower antioxidant levels, urban females deposited more tocopherol into the egg yolk. It appears that females from different breeding habitats may provide similar antioxidant protection for their offspring against oxidative damage by depositing different specific dietary antioxidants. Egg yolk lutein and retinol levels showed a negative relationship with lead concentration of the eggshell, which may suggest that lead had a negative impact on the amount of antioxidants available for embryos during development in great tits. [ABSTRACT FROM AUTHOR]

Abstract: Carotenoids and fat-soluble vitamins play crucial roles in several physiological processes. Yolk carotenoid composition may be influenced by the bird''s dietary intake and by the possible discrimination during carotenoid metabolism. Information regarding the pigment composition of passerine eggs is very limited. In the present 2-year study, we determined the carotenoid and vitamin concentrations and the percentage profile of carotenoid components in collared flycatcher (Ficedula albicollis) eggs. The major carotenoid was lutein in both years, followed by cis-lutein, zeaxanthin and β-carotene as other significant components. Carotenoid concentration was higher in 2000 than in 2001. As caterpillar abundance and ambient temperature was lower in 2001 than in 2000, we suggest that the decreased availability of carotenoid-rich resources and the elevated antioxidant demand of the female restricted the carotenoid allocation to the eggs. Our study is the first to indicate that the concentration and profile of yolk carotenoids may considerably vary in the same wild bird population between breeding seasons with different environmental conditions. Compared to other birds, the yolk of this species was relatively rich in vitamins A and E. Vitamin E concentration was positively correlated with total carotenoid concentration, which may be beneficial for the nestlings as these antioxidants synergistically provide better protection. [Copyright &y& Elsevier]

Schizotypy refers to a set of heritable, continuously distributed personality traits that resemble signs and symptoms of schizophrenia in the general population. It has been argued that studying the genetic background of schizotypy may yield valuable information about the etiology of schizophrenia. This study examined the association between selected genetic factors and schizotypal traits in 346 healthy college students. Self-reported schizotypal traits were measured using the Schizotypal Personality Questionnaire - Brief Revised. After scrutinizing available genome-wide association studies, we chose a set of single-nucleotide polymorphisms (SNPs) and focused on 8 genes associated with symptoms of schizophrenia-spectrum disorders. The analysis revealed that the AA variant of the SNP rs6913660 on the HIST1H2BJ gene was associated with higher intensity of magical thinking, a component of positive schizotypy. Furthermore, the CT variant of the SNP rs778293 on the D-amino acid oxidase activator (DAOA) gene and the CT variant of the SNP rs61867293 on the sortilin-related receptor SORCS3 gene were both related to excessive social anxiety, an aspect of interpersonal/negative schizotypy. By documenting the genetic associations of magical thinking and social anxiety we aim to provide a deeper insight into the translational mechanisms underpinning the emergence of schizotypal traits and individual differences in social functioning and belief formation. • Rs778293 SNP on the DAOA/G30 locus accounts for multiple susceptibility variants linked to SSD's affective symptoms. • Magical thinking, as a major function of the cognitive symptoms of schizotypy, is linked to the major histone variant complex HIST1H2BJ. • Association of magical thinking and rs6913660 SNP may be a theoretical starting point to understand the SSD-related symptoms. [ABSTRACT FROM AUTHOR]