Drosophila Activity Monitor (DAM): A Method to Measure Locomotor Activity in Flies

- The Drosophila Activity Monitor, or DAM, holds centered activity tubes equipped with fly food at one end and an air-permeable closer at the other. This setup accommodates single flies during experiments lasting several days or even weeks.

Place the DAM in a controlled environment like an incubator with set temperature, humidity, and light cycle. Conduct the experiment in a dark room and, if necessary, use an infrared light source to handle the device, which unlike bright light, does not influence the fly's circadian system.

To record locomotor activity, connect the apparatus to a computer system that stores the readings from the DAM's detectors. The DAM's electronics continuously detect the integrity of an infrared beam that is emitted through the midpoint of each tube and periodically upload data to the computer system.

As the fly walks back and forth inside the tube, it crosses the infrared beam. These interruptions are counted by the DAM over time for each tube and serve as a measure of fly activity.

In the following protocol, we will use the DAM system to study circadian rhythms in Drosophila adult males.

- Prior to loading flies into activity tubes, turn on the incubators th