title: Sound production in the tiger-tail seahorse Hippocampus comes: Insights into the sound producing mechanisms.
abstract: Acoustic signals of the tiger-tail seahorse (Hippocampus comes) during feeding were studied using wavelet transform analysis. The seahorse "click" appears to be a compounded sound, comprising three acoustic components that likely come from two sound producing mechanisms. The click sound begins with a low-frequency precursor signal, followed by a sudden high-frequency spike that decays quickly, and a final, low-frequency sinusoidal component. The first two components can, respectively, be traced to the sliding movement and forceful knock between the supraorbital bone and coronet bone of the cranium, while the third one (purr) although appearing to be initiated here is produced elsewhere. The seahorse also produces a growling sound when under duress. Growling is accompanied by the highest recorded vibration at the cheek indicating another sound producing mechanism here. The purr has the same low frequency as the growl; both are likely produced by the same structural mechanism. However, growl and purr are triggered and produced under different conditions, suggesting that such "vocalization" may have significance in communication between seahorses.
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: A C O
authors.initials: AC
authors.lastname: Lim
authors.affiliation: Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: V C
authors.initials: VC
authors.lastname: Chong
authors.affiliation: Physics Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: W X
authors.initials: WX
authors.lastname: Chew
authors.affiliation: Physics Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: S V
authors.initials: SV
authors.lastname: Muniandy
authors.affiliation: Physics Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: C S
authors.initials: CS
authors.lastname: Wong
authors.affiliation: Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Z C
authors.initials: ZC
authors.lastname: Ong
mesh_terms: D000818:Animals; D002610:Cheek; D005247:Feeding Behavior; D005583:Fourier Analysis; D012886:Skull / Q000000981:diagnostic imaging / Q000502:physiology; D023701:Smegmamorpha / Q000502:physiology*; D013016:Sound; D014057:Tomography, X-Ray Computed; D014732:Vibration; D014828:Vocalization, Animal / Q000502:physiology*; D058067:Wavelet Analysis