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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2008.05.027 Byline: Carlo Catoni, Anne Peters, H. Martin Schaefer Abstract: The expression of most life history traits, such as immunity, growth and the development of sexual signals, is negatively affected by high levels of oxidative stress. Dietary antioxidants can reduce oxidative stress and have therefore been the focus of numerous studies in behavioural and evolutionary ecology in the last few decades. Most of this research has focused on carotenoids, neglecting a number of more common, more potent, and thereby potentially more important, antioxidants, such as polyphenolic antioxidants. However, the effects of several classes of antioxidants on different life history traits have been thoroughly investigated in medical and animal-breeding studies. We suggest that behavioural and evolutionary studies will benefit from incorporating these advances. By reviewing the literature on the effects of antioxidants on life history traits in fish, birds and mammals, we develop a broad framework for dietary antioxidants. Fundamental properties of antioxidants, in particular their biochemistry, their potency and the interactions between them affect their relative relevance for life history traits. Based on tissue affinity, we distinguish between two categories of dietary antioxidants: focal antioxidants that are intrinsically important for a given trait and nonfocal antioxidants that influence traits only indirectly. Furthermore, we show how temporal and spatial environmental variability in antioxidant availability, as well as individual variation in food selection, may generate interindividual differences in the expression of life history traits. Finally, we suggest future research lines and experimental designs that may provide basic information needed to advance our knowledge of the ecological and evolutionary relevance of dietary antioxidants. Author Affiliation: (a) Faculty of Biology, Department of Evolutionary Biology and Animal Ecology, University of Freiburg, Germany (a ) Behavioural Ecology of Sexual Signals Group, Max Planck Institute for Ornithology, Germany Article History: Received 15 March 2008; Revised 21 April 2008; Accepted 30 May 2008 Article Note: (miscellaneous) MS. number: D-08-00186

The 'Defence Indication hypothesis' focuses on the multiple protective functions of anthocyanins and carotenoids as pigments and the evolvement of plant coloration primarily in response to various stressors. The reaction of the insects to plant coloration is explained with the help of the effects of the pigments and shared defense responses of the plants.

Author(s): Santiago Soliveres (corresponding author) [1]; Fons van der Plas [1, 2]; Peter Manning [1, 2]; Daniel Prati [1]; Martin M. Gossner [3, 4]; Swen C. Renner [5, 6]; Fabian [...]

Abstract Background While the gene flow in some organisms is strongly affected by physical barriers and geographical distance, other highly mobile species are able to overcome such constraints. In southern South America, the Andes (here up to 6,900 m) may constitute a formidable barrier to dispersal. In addition, this region was affected by cycles of intercalating arid/moist periods during the Upper/Late Pleistocene and Holocene. These factors may have been crucial in driving the phylogeographic structure of the vertebrate fauna of the region. Here we test these hypotheses in the burrowing parrot Cyanoliseus patagonus (Aves, Psittaciformes) across its wide distributional range in Chile and Argentina. Results Our data show a Chilean origin for this species, with a single migration event across the Andes during the Upper/Late Pleistocene, which gave rise to all extant Argentinean mitochondrial lineages. Analyses suggest a complex population structure for burrowing parrots in Argentina, which includes a hybrid zone that has remained stable for several thousand years. Within this zone, introgression by expanding haplotypes has resulted in the evolution of an intermediate phenotype. Multivariate regressions show that present day climatic variables have a strong influence on the distribution of genetic heterogeneity, accounting for almost half of the variation in the data. Conclusions Here we show how huge barriers like the Andes and the regional environmental conditions imposed constraints on the ability of a parrot species to colonise new habitats, affecting the way in which populations diverged and thus, genetic structure. When contact between divergent populations was re-established, a stable hybrid zone was formed, functioning as a channel for genetic exchange between populations.

Abstract Background Foraging behaviour is an essential ecological process linking different trophic levels. A central assumption of foraging theory is that food selection maximises the fitness of the consumer. It remains unknown, however, whether animals use innate or learned behaviour to discriminate food rewards. While many studies demonstrated that previous experience is a strong determinant of complex food choices such as diet mixing, the response to simple nutritional stimuli, such as sugar concentrations, is often believed to be innate. Results Here we show that previous experience determines the ability to track changes in sugar composition in same-aged individuals of a short-lived migratory songbird, the garden warbler (Sylvia borin). Although birds received identical foods for seven months prior to the experiment, wild-caught birds achieved higher sugar intake rates than hand-raised birds when confronted with alternative, differently coloured, novel food types. Hand-raised and wild birds did not differ in their initial colour selection or overall food intake, but wild birds were quicker to adjust food choice to varying sugar intake. Conclusion Over a period of at least seven months, broader previous experience translates into a higher plasticity of food choice leading to higher nutrient intake. Our results thus highlight the need to address previous long-term experience in foraging experiments. Furthermore, they show that hand-raised animals are often poor surrogates for testing the foraging behaviour of wild animals.