Bose A P H, Adragna J B, Balshine S
Aquatic Behavioural Ecology Laboratory, Department of Psychology, Neuroscience, & Behaviour, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L8 Canada.
J Fish Biol. 2017 Jan;90(1):311-325. doi: 10.1111/jfb.13187. Epub 2016 Nov 1.
In this study, the morphology of sagittal otoliths of the plainfin midshipman fish Porichthys notatus was compared between populations, sexes and male alternative reproductive phenotypes (known as 'type I males or guarders' and 'type II males or sneakers'). Sagitta size increased with P. notatus size and changes in shape were also detected with increasing body size. Porichthys notatus sagittae begin as simple rounded structures, but then elongate as they grow and take on a more triangular and complex shape with several prominent notches and indentations along the dorsal and caudal edges. Moreover, the sagittae of the two geographically and genetically distinct populations of P. notatus (northern and southern) differed in shape. Porichthys notatus from the north possessed taller sagittae with deeper caudal indentations compared to P. notatus from the south. Sagitta shape also differed between females and males of the conventional guarder tactic. Furthermore, guarder males had smaller sagittae for their body size than did sneaker males or females. These differences in sagittal otolith morphology are discussed in relation to ecological and life history differences between the sexes and male tactics of this species. This is the first study to investigate teleost otolith morphology from the perspective of alternative reproductive tactics.
在本研究中，比较了细纹后肛鱼（Porichthys notatus）矢耳石的形态在不同种群、性别以及雄性替代繁殖表型（即“ I型雄性或守卫者”和“ II型雄性或偷腥者”）之间的差异。矢耳石的大小随细纹后肛鱼的体型增大而增加，并且随着体型的增加，其形状也发生了变化。细纹后肛鱼的矢耳石最初是简单的圆形结构，但随着生长会逐渐拉长，并呈现出更三角形且复杂的形状，沿背缘和尾缘有几个明显的缺口和凹陷。此外，细纹后肛鱼两个地理和遗传上不同的种群（北部和南部）的矢耳石在形状上有所不同。与南部的细纹后肛鱼相比，北部的细纹后肛鱼拥有更高的矢耳石和更深的尾凹陷。传统守卫策略的雌性和雄性之间矢耳石形状也有所不同。此外，守卫雄性相对于其体型而言，矢耳石比偷腥雄性或雌性更小。本文讨论了矢耳石形态的这些差异与该物种两性之间的生态和生活史差异以及雄性策略的关系。这是首次从替代繁殖策略的角度研究硬骨鱼类耳石形态的研究。
