Figure 1. Path diagram with predicted trophic relationships based on previous studies. Single-headed arrows indicate hypothesized causal relationships, double-headed arrows indicate correlations; arrows do not indicate type of effect (positive versus negative). “L” pathway includes predicted causal relationships in low diversity fields; “H” pathway includes predicted causal relationships in high diversity fields. Correlations between other variables are also predicted to be important in both types of fields. H’ - Shannon-Weiner Diversity Index; ni – abundance.