The interaction structure of mutualistic relationships, in terms of relative specialization of the partners, is important to understanding their ecology and evolution. Analyses of the mutualistic interaction between anemonefish and their host sea anemones show that the relationship is highly nested in structure, generalist species interacting with one another and specialist species interacting mainly with generalists. This supports the hypothesis that the configuration of mutualistic interactions will tend towards nestedness. In this case, the structure of the interaction is at a much larger scale than previously hypothesized, across more than 180 degrees of longitude and some 60 degrees of latitude, probably owing to the pelagic dispersal capabilities of these species in a marine environment. Additionally, we found weak support for the hypothesis that geographically widespread species should be more generalized in their interactions than species with small ranges. This study extends understanding of the structure of mutualistic relationships into previously unexplored taxonomic and physical realms, and suggests how nestedness analysis can be applied to the conservation of obligate species interactions.

Edge effects encompass a complex panoply of biotic and biotic phenomena across woodlan borders. I identify four main explanations which have been proposed to explain avian habital selection with respect to forest edges: 1) individualistic resource and patch use. 2) biotic interactions: 3) microclimate modification 4) changes in vegetation structure. In relates nest site location in woodlands relative to the edge to the proximity of food resources. It is shown that all other things being equal birds which are wholly dependent on resources found within woodlands will tend to avid forest edges. Woodland species dependent upon resources found in adjacent habitats will tend to be found near to edges to enable their exploitation. 2) identifies competition predation and brood parasitism as factor which have the potential to influence bird habitat selection near edges. 3) identifies microclimate modification as a potential influence which may are directly on nesting success or indirectly through its effects on food supply: 4) relates the activities of birds such as nesting feeding or Research on edge effects of birds in woodland has provided few practical recommendations to conservation managers. Forest edge management needs to take into account the multiple cause and defects which influence habitat selection at the edge and to target species of conservation concern.

Pollinators play a key role within most terrestrial communities in maintaining plant populations, as well as pollinating many agricultural crops for seed and fruit production. The mobility of pollinating animals is significant to their importance but we know little about how landscape structure influences pollinator movements. Linear landscape features such as hedgerows and embankments are conspicuous features of agricultural landscape structure and are important artificial habitats in their own right. However, there has been some debate as to the function of these landscape elements as corridors between larger expanses of semi-natural habitat separated by urban and agricultural habitats. Few studies have specifically studied insect flight responses to linear landscape elements. By observing bumblebee flight behaviour along hedgerows and, by creating a medium-scale experimental array of flower patches using an artificial linear feature, we examined whether such structures can elicit an oriented flight response along them and therefore facilitate insect movement through the landscape. We found that both hedgerows and artificial linear landscape features can influence the flight directions of bumblebees (Bombus spp. Hymenoptera, Apidae), one of Europe's most important groups of pollinators. A bioassay experiment in which Salvia pratensis (Lamiaceae) was planted into landscape patches with differing numbers of connecting hedgerows showed that this directional response can have a profound effect on plant reproductive success -plants had increased pollinator activity, pollen receipt and subsequent seed set in patches with more connections. The overall hedgerow connectedness of a landscape is therefore important both to bumblebee movement and to those plants which depend on bumblebees for pollination services.

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