Figure 4
From: Rare symbionts may contribute to the resilience of coral–algal assemblages
Robustness of the coral–Symbiodinium community, measured as the fraction of remaining samples, to removal of Symbiodinium OTUs; (a) removal strategies depicted: random order (blue), according to their degree (that is, presence in coral samples; white), or according to their abundance (black). Removing components in increasing order of degree (red) shows a more stable scenario compared to removal in random order. When components with the highest degree are removed first (white), the robustness of the system quickly decreases and falls below linear loss of species, indicating that common Symbiodinium OTUs contribute overproportionally to maintaining host–symbiont assemblages. (b) Allowing for adaptation by introducing the probability that a removed OTU can be replaced by co-occurring OTUs increases the fraction of surviving samples. The probability that an existing OTU replaces the removed OTU increases from 0.1 to 1.0 at intervals of 0.1 from bottom to top (red lines).
