Table 1. Monte Carlo randomization tests (n = 1,000) for mean S(f) value and mean maximum S(f) frequency changes in the HFR periodical signal ranging from 1 to 3 Hz at different resource concentration scenarios.

	Experiment A		Experiment B		Experiment A		Experiment B
Resource comparison	Mean S(f)	P	Mean S(f)	P	Mean maximum frequencies	P	Mean maximum frequencies	P
High vs. low	2.68 vs. 11.48	0.000	1.59 vs. 3.55	0.000	1.69 vs. 1.96	0.004	1.87 vs. 1.91	0.562
High vs. medium	2.68 vs. 8.15	0.000	1.59 vs. 3.19	0.000	1.69 vs. 1.99	0.004	1.87 vs. 1.99	0.185
Medium vs. low	8.15 vs. 11.48	0.007	3.19 vs. 3.55	0.341	1.99 vs. 1.96	0.740	1.99 vs. 1.91	0.248