Organismal movement is ubiquitous and facilitates important ecological mechanisms that drive community and metacommunity composition and hence biodiversity. In most existing ecological theories and models in biodiversity research, movement is represented simplistically, ignoring the behavioural basis of movement and consequently the variation in behaviour at species and individual levels. However, as human endeavours modify climate and land use, the behavioural processes of organisms in response to these changes, including movement, become critical to understanding the resulting biodiversity loss. Here, we draw together research from different subdisciplines in ecology to understand the impact of individual‐level movement processes on community‐level patterns in species composition and coexistence. We join the movement ecology framework with the key concepts from metacommunity theory, community assembly and modern coexistence theory using the idea of micro–macro links, where various aspects of emergent movement behaviour scale up to local and regional patterns in species mobility and mobile‐link‐generated patterns in abiotic and biotic environmental conditions. These in turn influence both individual movement and, at ecological timescales, mechanisms such as dispersal limitation, environmental filtering, and niche partitioning. We conclude by highlighting challenges to and promising future avenues for data generation, data analysis and complementary modelling approaches and provide a brief outlook on how a new behaviour‐based view on movement becomes important in understanding the responses of communities under ongoing environmental change.

Recent studies showed that diverse wild bee assemblages are more efficient pollinators than honeybees. In urban ecosystems pollination services are also important, for example for the reproduction of many plant species in parks, for the production of vegetables and fruits in home gardens, as well as other animals depending on bee‐pollinated plants. This study investigates the effect of ‘urbanity’ on the abundance, species richness and community structure of wild bees foraging at city trees and quantifies the contribution of wild bees and honeybees to successful pollination. Four common city tree species in Berlin, Germany, were sampled in three parks defined as ‘green spaces’ and compared with trees in more ‘urban areas’. In total, 57 wild bee species foraged at the observed trees representing 19 % of all known species in Berlin. Wild bee species richness showed only small differences between green spaces and urban areas even though social species were found more frequently in green areas. Wild bees visited flowers more frequently in green areas, whereas the numbers of honeybee flower visits were higher in urban areas. Wild bee but not honeybee flower visits showed a positive relationship with the reproductive success of trees. The results suggest that wild bees are important pollinators of city trees that dominate the pollinator community in green spaces. To support wild bee communities green spaces should be preserved and tree species with floral reward should be planted and preserved in urban areas.

Flower nectar is a sugar-rich ephemeral habitat for microorganisms. Nectar-borne yeasts are part of the microbial community and can affect pollination by changing nectar chemistry, attractiveness to pollinators or flower temperature if yeast population densities are high. Pollinators act as dispersal agents in this system; however, pollination events lead potentially to shrinking nectar yeast populations. We here examine how sufficiently high cell densities of nectar yeast can develop in a flower. In laboratory experiments, we determined the remaining fraction of nectar yeast cells after nectar removal, and used honeybees to determine the number of transmitted yeast cells from one flower to the next. The results of these experiments directly fed into a simulation model providing an insight into movement and colonization ecology of nectar yeasts. We found that cell densities only reached an ecologically relevant size for an intermediate pollination probability. Too few pollination events reduce yeast inoculation rate and too many reduce yeast population size strongly. In addition, nectar yeasts need a trait combination of at least an intermediate growth rate and an intermediate remaining fraction to compensate for highly frequent decimations. Our results can be used to predict nectar yeast dispersal, growth and consequently their ecological effects.

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