Functional Adaptation of Vocalization Revealed by Morphological and Histochemical Characteristics of Sonic Muscles in Blackmouth Croaker (Atrobucca nibe).

Hung-Tai Lee,Cheng-Hsin Liao,Bao-Quey Huang

doi:10.3390/biology11030438

Abstract

Simple SummarySound production is common in numerous fish species. Some species can emit calls through the contraction of specialized muscles called sonic or drumming muscles. The sonic muscles of fish are among the fastest muscles in vertebrates. Although numerous studies have investigated the mechanism underlying sound production in fish, only the distinct features of the sonic muscles of a few species have been investigated. We demonstrated that the sonic muscles have functionally adapted for fast twitching and fatigue resistance, which support vocalization in the blackmouth croaker (Atrobucca nibe).Sound production in the blackmouth croaker (Atrobucca nibe) was characterized using acoustic, morphological, and histochemical methods. Their calls consisted of a train of two to seven pulses; the frequency ranged from 180 to 3000 Hz, with a dominant frequency of 326 ± 40 Hz. The duration of each call ranged from 80 to 360 ms. Male A. nibe possess a pair of bilaterally symmetric sonic muscles attached to the body wall adjacent to the swim bladder. The average diameter of the sonic muscle fibers was significantly shorter than that of the abdominal muscle fibers. Semithin sections of the sonic muscle fibers revealed a core-like structure (central core) and the radial arrangement of the sarcoplasmic reticulum and myofibrils. Numerous mitochondria were distributed within the central core and around the periphery of the fibers. Most of the fibers were identified as Type IIa on the basis of their myosin adenosine triphosphatase activities, but a few were identified as Type IIc fibers. All sonic muscle fibers exhibited strong oxidative enzyme activity and oxidative and anaerobic capabilities. The features suggest that the sonic muscles of A. nibe are morphologically and physiologically adapted for fast twitching and fatigue resistance, which support fish vocalization.

Highlights

Introduction published maps and institutional affilAnimal communication is the transmission of information between individuals through various sensory signals, such as light, sound, chemicals, touch, hydrodynamics, and electricity [1]
This study investigated the mechanism underlying sound production in A. nibe through a comprehensive method
The calls emitted by A. nibe had distinct sound parameters, namely dominant frequency, pulse number, and call duration

Summary

Introduction

Animal communication is the transmission of information between individuals through various sensory signals, such as light, sound, chemicals, touch, hydrodynamics, and electricity [1]. Sound signals are the most effective sensory modality because, in aquatic environments, they travel faster and farther than any other sensory signals [2,3]. Sound production has been widely observed in teleost species [4,5] and is correlated with behavioral responses such as feeding, aggression, territorialism, and reproduction [6]. The mechanisms of sound production in fish are complex and diverse, with three major mechanisms being involved [4,7]. Hydrodynamic sounds are produced through changes in direction and velocity as fish move. Stridulatory sounds are produced by friction of the teeth, fin spines, or bones of fish. Swim bladder sounds are produced by the contraction of specialized muscles known as sonic or drumming iations

Methods

Discussion

Conclusion