Green P A, Patek S N
Biology Department, Duke University
Biology Department, Duke University.
Biol Lett. 2015 Sep;11(9):20150558. doi: 10.1098/rsbl.2015.0558.
Mantis shrimp strike with extreme impact forces that are deadly to prey. They also strike conspecifics during territorial contests, yet theoretical and empirical findings in aggressive behaviour research suggest competitors should resolve conflicts using signals before escalating to dangerous combat. We tested how Neogonodactylus bredini uses two ritualized behaviours to resolve size-matched contests: meral spread visual displays and telson (tailplate) strikes. We predicted that (i) most contests would be resolved by meral spreads, (ii) meral spreads would reliably signal strike force and (iii) strike force would predict contest success. The results were unexpected for each prediction. Contests were not resolved by meral spreads, instead escalating to striking in 33 of 34 experiments. The size of meral spread components did not strongly correlate with strike force. Strike force did not predict contest success; instead, winners delivered more strikes. Size-matched N. bredini avoid deadly combat not by visual displays, but by ritualistically and repeatedly striking each other's telsons until the loser retreats. We term this behaviour 'telson sparring', analogous to sparring in other weapon systems. We present an alternative framework for mantis shrimp contests in which the fight itself is the signal, serving as a non-lethal indicator of aggressive persistence or endurance.
雀尾螳螂虾攻击时的冲击力极大，足以致命。它们在争夺领地时也会攻击同类，但攻击行为研究的理论和实证结果表明，竞争者在升级为危险战斗之前，应该通过信号来解决冲突。我们测试了布氏新齿指虾如何利用两种仪式化行为来解决体型相当的争斗：展开meral视觉展示和用尾扇（尾板）攻击。我们预测：（i）大多数争斗将通过展开meral来解决；（ii）展开meral能可靠地表明攻击力度；（iii）攻击力度能预测争斗的胜负。每个预测的结果都出人意料。争斗并非通过展开meral来解决，而是在34次实验中的33次升级为攻击。展开meral各部分的大小与攻击力度没有强烈关联。攻击力度无法预测争斗的胜负；相反，获胜者发动的攻击更多。体型相当的布氏新齿指虾避免致命战斗，不是通过视觉展示，而是通过仪式化地反复击打对方的尾扇，直到失败者撤退。我们将这种行为称为“尾扇搏击”，类似于其他武器系统中的搏击。我们提出了一个关于雀尾螳螂虾争斗的替代框架，其中争斗本身就是信号，作为攻击性坚持或耐力的非致命指标。
