Spiny Lobsters Stick and Slip to Make Sound

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Spiny Lobsters Stick and Slip to Make Sound

• Patek SN. 2001. Spiny lobsters stick and slip to
  make sound. Nature 411153-154.

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Spiny Lobster
Panulirus argus (modified from Summers, 2001)
Panulirus ornatus (Patek, 2001)
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Frictional Mechanism
(modified from Patek,2001)
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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
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Sound Production

• Only during sliding movements.
• Only when plectrum moves posteriorly against the
  anteriorly projecting shingles.

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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

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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.

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References

• Patek SN. 2001. Spiny lobsters stick and slip to
  make sound. Nature 411153-154.
• Summers A. 2001. The Lobsters Violin. Natural
  History 11026-27.