Frugivorous tephritid (Diptera: Tephritidae) females compete over access to fruit for oviposition through aggressive interactions. These aggressive displays are for oviposition site maintenance to reduce the probability of subsequent larval competition. While female aggressive behaviours have been described for several frugivorous tephritid species, studies quantifying behavioural frequencies and sequences and examining how quality of the host fruit might modify the intensity of aggressive behaviours are minimal or absent. We used behavioural analysis software of video playback to describe and quantify antagonistic behaviours between pairs of Bactrocera tryoni females and measured changes in the frequency of behaviours when females were defending three fruit types known to vary in their quality for offspring development. Seven behaviours were identified as part of competitive contests between B. tryoni females, which were not performed in any regular order or with any obvious escalation in the intensity of an aggressive display. Crabbing, [wing] supination and pushing were the most common behaviours, constituting 78% of all observed aggressive behaviours. Increasing fruit quality resulted in aggressive behaviours happening significantly sooner and more often. Our results are similar to previous studies in the types of behaviours exhibited by female frugivorous tephritids but are contrary to other studies in that no sequential pattern or escalation of behaviours was documented. Increased female investment in defence of higher quality hosts aligns with theoretical predictions but has not been previously tested.

中文翻译：

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Bactrocera tryoni（双翅目：实蝇科）雌性之间的攻击行为以及果实品质对战斗强度的影响

食果性实蝇（双翅目：实蝇科）雌性通过侵略性的相互作用来争夺果实以产卵。这些侵略性的展示是为了维护产卵地点，以减少随后幼虫竞争的可能性。虽然已经描述了几种食果性实蝇物种的雌性攻击行为，但量化行为频率和序列以及检查寄主果实的质量如何改变攻击行为强度的研究很少或不存在。我们使用视频播放行为分析软件来描述和量化一对巴西实蝇雌性之间的对抗行为，并测量当雌性捍卫三种已知其后代发育质量不同的水果类型时行为频率的变化。七种行为被确定为B.tryoni雌性之间竞争性竞赛的一部分，这些行为没有按任何常规顺序进行，也没有明显增强攻击性表现的强度。抓捕、[翅膀]旋后和推动是最常见的行为，占所有观察到的攻击行为的 78%。提高水果质量会导致攻击行为发生得更快、更频繁。我们的结果与之前关于雌性食果性实蝇表现出的行为类型的研究相似，但与其他研究相反，因为没有记录行为的顺序模式或升级。女性在防御更高质量宿主方面的投资增加与理论预测一致，但之前未经测试。