In: Ecosphere, 2011, vol. 2, no. 12, p. art133
Optimal diet theory (ODT) postulates that predators adjust their foraging decisions by calculating a prey value from the potential biomass gain, handling time, prey vulnerability and encounter rate. Tests of ODT have however so far mainly been restricted to laboratory settings. By video surveillance, we gathered a large data set of more than 2000 field observations of crab spider (Misumena vatia)...
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In: Evolution, 2010, vol. 64, no. 12, p. 3629–3633
Müller's theory of warning color and mimicry, despite forming a textbook example of frequency-dependent selection, has rarely been demonstrated in the wild. This may be largely due to the practical and statistical difficulties of measuring natural selection on mobile prey species. Here we demonstrate that this selection acts in alpine beetle communities by using tethered beetles exposed to...
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In: Weed Research, 2011, vol. 51, no. 6, p. 559–573
The recent invasion by Ambrosia artemisiifolia (common ragweed) has, like no other plant, raised the awareness of invasive plants in Europe. The main concerns regarding this plant are that it produces a large amount of highly allergenic pollen that causes high rates of sensitisation among humans, but also A. artemisiifolia is increasingly becoming a major weed in agriculture. Recently, chemical...
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In: Molecular Phylogenetics and Evolution, 2012, vol. 62, no. 2, p. 612–623
Spotted knapweed (Centaurea stoebe) occurs from Western Asia to Western Europe both as diploid and tetraploid cytotypes, predominantly in single-cytotype populations with higher frequency of diploid populations. Interestingly, only tetraploids have been recorded so far from its introduced range in North America where they became highly invasive. We performed phylogenetic and network analyses of...
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In: Insect Conservation and Diversity, 2011, vol. 4, no. 1, p. 60-80
1. Sown wildflower strips are increasingly being established in European countries within agri-environmental schemes to enhance biodiversity, especially in intensively used agricultural areas.2. The regulations vary between countries regarding the seed mixture, intensity of management and period of time over which subsidies are given. Insects in particular are intended to benefit from these...
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In: Ecology, 2011, vol. 92, no. 12, p. 2183–2189
Body mass is a fundamental characteristic that affects metabolism, life history, and population abundance and frequently sets bounds on who eats whom in food webs. Based on a collection of topological food webs, Ulrich Brose and colleagues presented a general relationship between the body mass of predators and their prey and analyzed how mean predator–prey body-mass ratios differed among...
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In: Molecular Ecology, 2011, vol. 20, no. 11, p. 2442–2463
Pleistocene glacial and interglacial periods have moulded the evolutionary history of European cold-adapted organisms. The role of the different mountain massifs has, however, not been accurately investigated in the case of high-altitude insect species. Here, we focus on three closely related species of non-flying leaf beetles of the genus Oreina (Coleoptera, Chrysomelidae), which are often found...
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In: Plant Ecology, 2010, vol. 212, no. 2, p. 315-325
Invasion success is favoured by the introduction of pre-adapted genotypes. In addition, novel pressures in the introduced range may lead to phenotypic changes related to fitness or competitive ability of introduced plants. Polyploidy appears to be over-represented in invasive plants, but differences between cytotypes in growth strategies including trade-offs among plant traits have received...
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In: Ecology, 2011, vol. 92, no. 4, p. 829-835
One commonly accepted mechanism for biological invasions is that species, after introduction to a new region, leave behind their natural enemies and therefore increase in distribution and abundance. However, which enemies are escaped remains unclear. Escape from specialist invertebrate herbivores has been examined in detail, but despite the profound effects of generalist herbivores in natural...
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In: Journal of Biogeography, 2011, vol. 38, p. 1- 16
Aim Today’s genetic population structure and diversity of species can be understood as the result of range expansion from the area of origin, past climatic oscillations and contemporary processes. We examined the relative importance of these factors in Veratrum album L., a toxic weed of mountain grasslands. Location Continental Europe.Methods Forty...
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