Ethanol sedation assays (Figure S1 and S3) were initiated by transferring adult flies into empty 2.5 × 9.5 cm food vials (VWR; Radnor, PA, U.S.A.; catalogue number 89092-722). Cellulose acetate Flugs (FlyStuff.com; San Diego, CA, U.S.A.; catalogue number 49-102) were inserted 2 cm into each vial and the vials of flies were arranged into six rows of four vials each (Figure S3). The number of dead/inactive flies (on average <1%) was recorded for each vial at t=0 min and censored. Starting with the first row of 4 vials, ethanol (0–50%; 2 ml in our standard assay) was added at five-second intervals to the Flug in each vial and the vial was immediately sealed with a silicone stopper. The remaining rows of vials were treated identically at 1-minute intervals. Starting 6 minutes after adding ethanol to the Flugs and continuing at 6-minute intervals thereafter, each vial was gently tapped 3 times on a table and the number of sedated flies (i.e. flies that were noticeably uncoordinated or immobile) in each vial was recorded 30 seconds after the final tap. Ethanol sedation
