Spiny Lobsters Stick and Slip to Make Sound Patek SN. 2001. Spiny lobsters stick and slip to make sound. Nature 411:153-154.
Spiny Lobster Panulirus ornatus (Patek, 2001) Panulirus argus (modified from Summers, 2001)
Frictional Mechanism (modified from Patek,2001)
Purpose • Test which mechanism the palinurid lobsters (spiny lobsters) use to create sound. • Stick and Slip Mechanism ( Ex: Bow and Violin). • Washboard Mechanism. • Put motion detector to the plectrum. • Hydrophone to record sounds. Method
Only during sliding movements. Only when plectrum moves posteriorly against the anteriorly projecting shingles. Sound Production
Results • High speed video analysis showed shingle impacts (19,000-28,000 Hz) exceeding the average pulse rate (77 Hz). • Washboard mechanism would have shown equal pulse rates shingle impacts. • Electromyographic, acoustic and plectrum-movement recordings . • Showed promoter muscle contracting tonically during sound production. • Muscle contraction found to generate the series of sound pulses. • Manually sliding the plectrum over the file in a single motion produced a series of sound pulses. • Therefore, palinurid lobsters use the stick and slip mechanism
Stick and Slip Function • Lobsters rely on their hard spiny exoskeleton for protection. • The clicking sound startles predators. • Predators associate clicking sounds with the spiny exoskeleton . • Predators hear the sounds and back off, even if the lobster is molting and has a soft body.
References • Patek SN. 2001. Spiny lobsters stick and slip to make sound. Nature 411:153-154. • Summers A. 2001. The Lobster’s Violin. Natural History 110:26-27.