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Ecology

experimental tests of mechanistic theory

Competition for light between phytoplankton species: experimental tests of mechanistic theory Jef Huisman INTRODUCTION Light is the sole energy source for nearly all plant species, ranging from the tiny phytoplankton to giant sequoia trees. As a consequence, the availability of light has a major impact on the dynamics and structure of most aquatic and terrestrial […]

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Ecology

Metapopulation Biology: Ecology, Genetics, and Evolution.

Metapopulation Biology: Ecology, Genetics, and Evolution. – book reviews Chris Ray A growing emphasis on the conservation of species in fragmented habitats has propelled metapopulation studies to the forefront of ecological research. New spatial analysis tools allow ecologists to quantify patchiness in species distributions, and to ask ever more specific questions about how that patchiness […]

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Ecology

Rodent dispersal of vesicular-arbuscular mycorrrhizal fungi in Amazonian Peru

Rodent dispersal of vesicular-arbuscular mycorrrhizal fungi in Amazonian Peru David P. Janos Key words: Echimyidae; Glomus; Muridae; Peru; rodents; Sclerocystis; spore dispersal; tropical forest; vesicular-arbuscular mycorrhizal fungi. INTRODUCTION The absorptive roots of most plants associate mutualistically with zygomycetous fungi to form vesicular-arbuscular mycorrhizae (YAM) (Trappe 1987). VAM enhance uptake of mineral nutrients, especially those of […]

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Ecology

Selection of flowering time: an adaptive fitness surface for nonexistent character combinations

Selection of flowering time: an adaptive fitness surface for nonexistent character combinations Pamela O’Neil INTRODUCTION It has long been recognized that the timing of reproduction can have a considerable effect on fitness in a variety of different organisms. Reproductive synchrony has been shown to enhance reproductive success in plants (Schemske 1977, Waser 1978a, Thomson 1980, […]

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Ecology

Biodiversity: population versus ecosystem stability

Biodiversity: population versus ecosystem stability David Tilman INTRODUCTION Fragmentation, grazing, forestry, and nutrient deposition are decreasing the biological diversity of many of the earth’s remaining semi-natural ecosystems (e.g., Ehrlich and Ehrlich 1981, Aerts and Berendse 1988, Wilson 1988, 1992, Ehrlich and Daily 1993). Elton (1958:145-153) suggested that decreased diversity would lead to decreased ecological stability […]

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Ecology

The Natural History of Inbreeding and Outbreeding: Theoretical and Empirical Perspectives. – The Heterogenous Nucleation of Microcellular Foams Assisted by the Survival of Microvoids in Polymers Containing Low Glass Transition Particles, part 2

The Natural History of Inbreeding and Outbreeding: Theoretical and Empirical Perspectives. – The Heterogenous Nucleation of Microcellular Foams Assisted by the Survival of Microvoids in Polymers Containing Low Glass Transition Particles, part 2 – book reviews F. Stephen Dobson Does breeding between close relatives occur frequently in natural populations of plants and animals? In nature, […]

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Ecology

Dietary protein and energy as determinants of food quality: trophic strategies compared

Dietary protein and energy as determinants of food quality: trophic strategies compared Stephen H. Bowen INTRODUCTION Fundamental differences in food quality are evident when major food resource categories are compared. Protein and energy are two nutrients of particular interest to ecologists that show these differences clearly. Protein and energy are two “macronutrients” required for animal […]

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Ecology

evidence from field and laboratory experiments

Cannibalism regulates densities of young wolf spiders: evidence from field and laboratory experiments James D. Wagner INTRODUCTION Spiders are a ubiquitous and diverse group of terrestrial predators that often consume a substantial fraction of herbivore and detritivore populations (Van Hook 1971, Moulder and Reichle 1972, Manley et al. 1976). Descriptive and experimental studies have revealed […]

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Ecology

Consumer species richness and autotrophic biomass

Consumer species richness and autotrophic biomass Shahid Naeem INTRODUCTION Two issues are central to community ecology. These are, what governs variation in biotic diversity among ecosystems (the distribution and abundance of species) and what governs variation in standing biomass among ecosystems (the distribution and abundance of energy and materials among abiotic and biotic components)? Synthesizing […]

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Ecology

Foraging group size: models and a test with Jaegers kleptoparasitizing terns

Foraging group size: models and a test with Jaegers kleptoparasitizing terns Marc Belisle INTRODUCTION Models of foraging group size have dealt with the spatial distribution of foragers in simplistic environments without boundaries, where the food resources are contained within discrete patches at only one spatial scale (e.g., Caraco 1980, Clark and Mangel 1984, Giraldeau 1988, […]