Table 2. Slopes (exponent b) and R ² values for log oxygen consumption rates of whole organisms, hearts and brains vs log body mass for all five species combined and for each individual species ¹ .

		Organism	Heart	Brain
All five species	Slope ± Std. Err.	0.52 ± 0.05	0.55 ± 0.06 a	-0.09 ± 0.04
	R 2	0.44	0.34	0.04
Danio rerio	Slope ± Std. Err.	0.60 ± 0.1006	0.59 ± 0.09 a	-0.03 ± 0.04
	R 2	0.44	0.51	0.01
Fundulus heteroclitus	Slope ± Std. Err.	0.78 ± 0.12	0.71 ± 0.18 a	-0.16 ± 0.16
	R 2	0.62	0.38	0.04
Gambusia holbrooki	Slope ± Std. Err.	0.53 ± 0.17	0.50 ± 0.20 a	0.08 ± 0.06 a
	R 2	0.29	0.23	0.08
Oryzias latipes	Slope ± Std. Err.	0.41 ± 0.17	0.37 ± 0.13 a	0.02 ± 0.05
	R 2	0.18	0.23	0.01
Pimephales promelas	Slope ± Std. Err.	1.07 ± 0.11	1.04 ± 0.15 a	0.13 ± 0.08
	R 2	0.90	0.83	0.28

¹See S3 Table for Y intercept values, 95% confidence intervals and sample sizes.

^aExponent b for hearts or brains are statistically similar (P>0.05) to that of whole organisms (F (DFn, DFd) and P values are in S4 Table).