Figure 1.

Composition and diversity of the microcosm bacterial communities. The top row of panels shows the mean relative abundance of each bacterial taxon across the productivity gradient for (a) no predators, (b) Bodo sp., (c) Spumella sp., and (d) Cyclidium. sp. Colour intensity indicates the relative abundance of each bacterial taxon. The tRFLP fragment size (number of base pairs) associated with each taxon is shown on the y-axis. (e–h) shows the bacterial biodiversity, measured as the complement of the Simpson index (1 − λ), across the productivity gradient for each predator treatment. Broadly similar results are obtained if the Shannon–Wiener index is used (electronic supplementary material, figure S2). Curves are fitted regression lines.