Insects that are small or exhibit low metabolic rates are considered to not require active ventilation to augment diffusive gas exchange. Some pupae with low metabolic rates exhibit abdominal pumping, a behaviour that is known to drive tracheal ventilation in the adults of many species. However, previous work on pupae suggests that abdominal pumping may serve a non-respiratory role. To study the role of abdominal pumping in pupa of the beetle Zophobas morio, we visualized tracheal dynamics with X-rays while simultaneously measuring haemolymph pressure, abdominal movement, and CO2 emission. Pupae exhibited frequent tracheal compressions that were coincident with both abdominal pumping and pulsation of pressure in the haemolymph. However, more than 63% of abdominal pumping events occurred without any tracheal collapse and hence ventilation, suggesting that the major function of the abdominal pump is not respiratory. In addition, this study shows that the kinematics of abdominal pumping can be used to infer the status of the spiracles and internal behaviour of the tracheal system.
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part1
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_aa
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part2
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ab
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part3
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ac
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part4
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ad
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part5
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ae
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part6
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_af
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part7
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ag
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part8
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ah
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part9
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ai
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part10
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_aj
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part11
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ak
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part12
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_al
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part13
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_am
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part14
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_an
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part15
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ao
Data from: Tracheal compression in pupae of the beetle Zophobas morio_part16
Tracheal_compression_in_pupae_of_the_beetle_Zophobas_morio__Supplementary_Data_ap