Fig. 4. The relationship between anterior and posterior CO2 emission
rates during the discontinuous gas-exchange cycle (DGC) in Circellium
bacchus (N=53 DGCs in six beetles, mean mass 7.427 g). The
regression equations are: a=-0.022+0.891t,
r2=0.98, P=0.001;
p=0.022+0.109t, r2=0.4,
P=0.001, where a is anterior spiracular
CO2, p
is posterior spiracular
CO2 and
t is total
CO2. When the
mean values for each beetle (N=6) are used, the regression equations
are: a=-0.021+0.866t, r2=0.98,
P=0.002; p=0.021+0.134t,
r2=0.5, P=0.11.