Since vibrational systems are thought to be particularly sensitive to interference by noise, we studied its effects on three species of hemipterans. In the stink bug N. viridula, noise reduced the ability to recognize the artificial female calling song (FCS) and to localize its source. Noise spectrally overlapping the signals (SON) decreased the sensitivity of vibrational receptor neurons to FCS and disrupted its frequency encoding, while non-overlapping noise (NON) affected only frequency encoding. Modeling revealed that noise-induced changes in the song’s waveform disrupted key cues for localization. These findings indicate a novel masking mechanism potentially unique to vibrosensory systems and highlight the sensitivity of vibration-mediated behaviors to noise. Conversely, male leafhopper A. makarovi searching for the source of artificial female response song (FC) under biotic and abiotic vibrational noise achieved comparable localization success to the control group despite reduced signaling effort. Nonlinear amplitude gradients of the signals complicated localization but promoted rapid searching strategies with frequent turns, compensating for unclear directional cues on the plant. We measured the summaric frequency sensitivity of vibrational receptor neurons in two species of the genus Aphrodes, providing the first data in the literature for the suborder Auchenorrhyncha. In a comparative behavioral experiment with live pairs of leafhoppers, behavioral inhibition was primarily dependent on the spectrum of anthropogenic noise, which affected localisation ability in A. makarovi and additionally inhibited also signaling and searching in A. bicincta 'Dragonja'.
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