Table 2.

Outcomes of statistical models for the critical swimming speed (U_crit) of males that were subjected to three generations of artificial selection for adult predation survival versus their control lines. Number of individuals = 215 (predation line: 108, control line: 107).

	estimate	std error	t-value	p-value
fixed effects
(intercept)	3.605	0.112	32.307	<0.001
selection line (P)	0.020	0.017	1.149	0.251
standard length	−0.130	0.061	−2.12	0.034
replicate	−0.016	0.010	−1.536	0.124
random effects	variance	s.d.
group (intercept)	<0.001	0.006
residual	<0.001	0.117