Table 1.

Scaling of respiratory quantities $y$ with body mass $M$ given in units of kilograms, $y=a{(M/\text{kg})}^b$

Quantity $y$	Prefactor $a$	Exponent $b$	Source
Skull length $L$	$7\text{cm}$	$0.32\pm 0.01$	(18)
Surface area $S$	$19{\text{cm}}^2$	$0.74\pm 0.03$	(18)
Nasal volume $V$	$2.9{\text{cm}}^3$	$0.96\pm 0.03$	(18)
Tidal volume $V_{\mathrm{t}}$	$7.7{\text{cm}}^3$	$1.04\pm 0.01$	(33)
Respiratory rate $f$	$0.89{\text{s}}^{-1}$	$-0.26\pm 0.01$	(33)
Cross-section $A$	$0.4{\text{cm}}^2$	$0.63\pm 0.04$	$A=V/L$
Volumetric flux $Q$	$14{\text{cm}}^3/\text{s}$	$0.78\pm 0.02$	$Q=2V_{\mathrm{t}}f$