A novel acoustic-vibratory multimodal duet.

Area of Science:

• Animal behavior
• Bioacoustics
• Insect communication

Background:

• Crickets and bushcrickets typically use acoustic signals for mating.
• Females usually locate males via phonotaxis towards male calling songs.
• Onomarchus uninotatus males produce unusually low-pitched calls.

Purpose of the Study:

• Investigate female response to male acoustic signals in Onomarchus uninotatus.
• Determine if female vibrations serve as a substrate-borne signal for male localization.
• Characterize the novel multimodal communication system in this bushcricket species.

Main Methods:

• Recorded male acoustic calls and female vibrational responses.
• Utilized laser vibrometry to quantify female substrate-borne vibrations.
• Performed playback experiments with acoustic and vibratory signals to test male localization.

Main Results:

• Female response to male calls was bodily vibration (tremulation).
• A clear alternating phase relationship was observed between male calls and female vibrations.
• Males could localize vibration sources only when both acoustic and vibratory signals were presented.
• This represents the first known instance of female tremulation to a long-range acoustic signal in bushcrickets.

Conclusions:

• Onomarchus uninotatus engages in a novel multimodal duet involving acoustic and substrate-borne vibrational signals.
• This duetting system may be an adaptation to reduce predation risk for females.
• The study reveals the first known example of a multimodal duet in animals.