Appendix A. Statistical tables (means and results of analysis from the field experiments).
TABLE A1. Means and statistical analysis of pre-manipulation predator densities and fly egg predation rate, from the field experiment.
Treatment |
ANOVA output |
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Dependent variable |
AP-LG- |
AP-LG+ |
AP+LG- |
AP+LG+ |
Statistic |
Pm |
Alt |
Pm × Alt |
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Small beetle activity-density |
7.0±0.8 |
11.0±2.1 |
8.0±0.8 |
9.8±1.4 |
F1,16 |
4.35 |
0.01 |
0.63 |
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P. melanarius activity-density |
0 |
0.2±0.2 |
0 |
0 |
F1,16 |
1.00 |
1.00 |
1.00 |
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Eggs eaten |
0.6±0.4 |
0.6±0.3 |
1.2±0.7 |
1.6±0.7 |
F1,16 |
0.25 |
1.89 |
0.12 |
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Notes: Treatments: aphids removed, P. melanarius unmanipulated (AP-LG-); aphids added, P. melanarius unmanipulated (AP+LG-); aphids removed, P. melanarius added (AP-LG+); and aphids added, P. melanarius added (AP+LG+). Model terms: main effect of P. melanarius addition (Pm); main effect of aphid addition (Alt); interaction between P. melanarius and aphid addition (Pm × Alt).
TABLE A2. Statistical output for final arthropod densities, and for egg predation through time, from the field experiment.
Model term |
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Taxon |
Statistic |
Pm |
Alt |
Pm × Alt |
Time |
Time × Pm |
Time × Alt |
Time × Pm × alt |
Aphids |
F1,16 |
0.47 |
41.06 |
0.49 |
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P |
0.50 |
< 0.001 |
0.49 |
|||||
Small beetles |
F1,16 |
8.49 |
0.41 |
0.25 |
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P |
0.01 |
0.53 |
0.63 |
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Egg predation |
F1,16 |
0.006 |
0.151 |
11.84 |
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P |
0.94 |
0.71 |
0.003 |
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Wilks’ λ |
0.46 |
0.89 |
0.92 |
0.97 |
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F2,15 |
8.65 |
0.92 |
0.69 |
0.21 |
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P |
0.003 |
0.42 |
0.52 |
0.81 |
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TABLE A3. Statistical output for small beetle behavior under reproduced field conditions.
ANOVA |
Output |
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Statistic |
Pm |
Alt |
Pm × Alt |
F1,36 |
0.00 |
5.04 |
0.00 |
P |
1.00 |
0.03 |
1.00 |