Table S8.

Anticipation model: Effect of intergroup conflict anticipation on urinary oxytocin levels, log-transformed

Term	Estimate	SE	CIlower	CIupper	χ2*	P
Intercept	4.369	0.393	3.586	5.157	–	–
Test predictor
Preborder patrol with affiliation†	1.483	0.410	0.681	2.282	11.132	<0.001
Control predictors
Sex‡	−0.418	0.484	−1.418	0.554	0.697	0.404
Proximity§	0.261	0.166	−0.081	0.610	2.331	0.127
Subgroup size¶	−0.012	0.143	−0.311	0.270	0.007	0.935
Rank#	−0.150	0.199	−0.564	0.272	0.528	0.467
Affiliation duration||	0.167	0.172	−0.195	0.526	0.862	0.353

Statistically significant results (P ≤ 0.05) appear in bold.

^*Degrees of freedom are 1.

^†,‡χ² and P values refer to comparison with the reference categories ^†control with affiliation and ^‡female.

^§,¶,#,||z-transformed, mean ± SD of the original variables: ^§60.9 ± 25.97 (range 5 to 99), ^¶15.04 ± 5.21, ^#0.628 ± 0.27 (range 0 to 1, with 1 being the highest social rank), and ^||1357.64 ± 791.9 (s).