Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan.
J Exp Biol. 2011 Aug 15;214(Pt 16):2718-23. doi: 10.1242/jeb.057752.
Crayfish showed avoidance reactions when mechanical stimulation was applied to their tailfan. The response pattern of the avoidance reaction was dependent on crayfish size. Small crayfish showed an escape-like dart response while larger crayfish displayed a defensive-like turn response. We show that the response pattern to the same sensory stimulus changed with social status in the small crayfish. Crayfish are territorial animals and a dominant-subordinate relationship was determined when two previously unacquainted animals were paired. This winner-loser hierarchy was observed in pairs of small crayfish. Before fighting, all crayfish showed a dart response following mechanical stimulation of the tailfan. However, the probability of occurrence of a turn response increased significantly in the crayfish that won a fight. This behavioural transition from dart to turn response occurred immediately and was maintained for at least 3 days even if a dominant crayfish was isolated again with no opponent.
当机械刺激施加到螯虾的尾扇时，它们会表现出回避反应。回避反应的模式取决于螯虾的大小。小螯虾表现出类似于逃跑的冲刺反应，而大螯虾则表现出类似于防御的转弯反应。我们发现，对于相同的感觉刺激，小螯虾的反应模式会随着社会地位的变化而变化。螯虾是具有领地意识的动物，当两只以前不相识的动物被配对时，就会形成一种支配-从属关系。这种胜负等级关系在小螯虾的配对中观察到。在战斗之前，所有螯虾在机械刺激尾扇后都会表现出冲刺反应。然而，在赢得战斗的螯虾中，转弯反应的发生概率显著增加。这种从冲刺到转弯反应的行为转变是立即发生的，并且至少持续 3 天，即使一只占优势的螯虾再次与没有对手的隔离。
