In the past, getting an inside look at living bugs was difficult. During computerized tomography (CT) scans, the tiny subjects would squirm, causing image smearing and distortions. The solution, according to a new study: insect anesthesia. Like many animals, insects become sedentary when exposed to high levels of carbon dioxide (CO2). As reported this week in BMC Zoology, researchers subjected black and yellow–striped Colorado potato beetles (Leptinotarsa decemlineata) to a constant flow of CO2. Within seconds, the insects were not moving, but still alive. With these immobilized beetles, researchers were able to get up close and personal with the insides of the bug. The animals were kept asleep between 3 and 7 hours, depending on the complexity of the scan being performed. With the exception of a few older males, the subjects were easily woken up, and the repeated exposure to x-ray radiation and CO2 didn’t seem to harm them. Viewing the CT scans, the beetles’ guts come into full view, showing their complex tracheal system and exoskeleton. The researchers say that with this quick and safe method of knocking out bugs, clearer looks at the insides of living insects are in the near future, and with it, the ability to see the insect life cycle in full detail.