Figure 1.
Connectives between head and thoracic ganglia before (left) and after (right) lesion.
Ventral view of the locust neck incision exposing the connectives between head and thoracic ganglia before (left) and after (right) lesion. Following surgery the locusts were allowed 14–24 h for recovery, during which access to food was denied, prior to respirometry.
Table 1.
Gas exchange pattern distribution across the two locust phases and three experimental treatments (N = 133).
Figure 2.
Gas exchange patterns in connective-cut S. gregaria of both density-dependent phases, measured at 30°C.
Connective-cut gregarious locusts exhibited all three patterns (a, b, c: DGC, cyclic and continuous, respectively), at similar proportions compared with controls. Connective-cut solitary locusts abandoned DGC and displayed a typical continuous gas exchange pattern (d). Red lines indicate threshold value for determination of spiracle closure (see methods).
Figure 3.
Mass-specific metabolic rates of gregarious and solitary locusts across experimental treatments.
Mean (±s.e.m.) mass-specific CO2 emission rates (spCO2) of intact, sham-operated (SO), and connective-cut (CC) S. gregaria of both phases, measured at 30°C. Similar rates were measured for intact gregarious and solitary intact locusts (ANCOVA with body mass as a covariate, P = 0.22), but significant phase effect was found across treatments (Two-way ANCOVA, P = 0.003).