"No movement of the insects is left unobserved," wrote Popular Science in May 1924. Indeed, to gather data that might help commercial beekeepers, government researchers trained their eyes and a number of sensors on hives of 3,750,000 honeybees. With anemometers, barometers, hydrometers, and thermometers they monitored the bees' response to changing weather conditions. Magnifying glasses on the hives gave researchers a safe view of life inside. "Woe betide the unfortunate investigator—human or otherwise—who would personally invade the privacy of the bees' home!" we wrote. Now, scientists are outfitting insects with sensors to probe our environment. For example, cockroaches carrying a microphone and a microcontroller will be sent into disaster sites to detect survivors. Learn about how they work here.