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Co-flowering plant species (species that flower together in space and seasonal time) that share pollinators could compete for pollination. This can result in a negative effect on reproductive success for one or more species. Such plant species could compete for one or both of pollinator visits or pollen load quality. Plant species could minimise competition for pollinators (i) by using different pollinators, (ii) through spatial separation, (iii) by flowering at different seasonal times, (iv) by placing pollen on different parts of the same pollinator and (v) by segregating shared pollinators in daily time. In this thesis I investigate pollination interactions between plant species in (i) a guild of ten acacia species and (ii) an entire flowering plant community in Laikipia, Kenya. I examined the acacia species’ flowering phonologies to identify species that regularly co-flower. I compared daily patterns of dehiscence between co-flowering acacia species for evidence of character displacement on a daily timescale and assessed the extent to which (i) acacia species shared pollinators and (ii) shared pollinators are partitioned in daily time in response to patterns of pollen availability. A number of pollinator species were shared among acacia species making competition for pollination possible. Although up to five species of acacia regularly co-flowered, there was no consistent evidence to suggest that character displacement of dehiscence time had occurred among these species. Previous analyses have only considered the dynamics of co-flowering within guilds of related species. In this thesis I examined evidence for the daily partitioning of shared pollinators in a savannah plant community using a null model approach to analyse plant-pollinator interaction networks.