Table 1.

Conditionally rarity analysis.

	Number of conditionally rare nodes	Number of total nodes	Proportion conditional rare/total nodes	Fisher’s exact test P-value
Whole bacterial community	95	891	0.10
Dolichospermum	15	25	0.60	P < 0.001
Microcystis	1	6	0.16	P > 0.1

We compared the proportion of conditionally rare Microcystis or Dolichospermum MED nodes to the proportion expected among MED nodes in the entire lake bacterial community using Fisher’s exact test.