Predator-driven Intra-species Variation In Maintenance Metabolism,Personalities And Shoaling Behavior In Pale Chub(Zacco Platypus)

Predation risks varied profoundly with different aquatic habitats,and these predation regimes are usually expected to be a key trigger of divergent natural selection.To explore whether there exists predator-driven intra-species variation in the metabolism,personalities and shoaling behavior of pale chub(Zacco Platypus)inhabited in different environment,we measured standard metabolic rate(SMR),personality traits(i.e.activity,boldness,exploration,sociality)and shoaling traits(i.e.inter-individual distance,swimming speed and its synchronization of velocity,polarity)of six population(three from high predation risk while another three from low predation risk habitat)sampled along Wujiang River.The main findings of this research are as follows:1.The SMR,personalities,cohesion and moving polarity of shoals showed significant differences among different populations,whereas the swimming velocity and its synchronization exhibited no significant differences among populations.2.Neither the variation of SMR nor that of personalities showed any relationship with predation regime.3.The only change related to predation intensity was shoaling character as the fish from high-predation populations showed a lower swimming speed and synchronization compared to those from the low-predation populations.The whole results show that:1.The pale chub living in different habitats may have adaptive changes in both metabolism and behavior.2.The predation decreased the speed while moving and synchronization of speed of high-predation populations,it is likely to increase the vigilance.3.The lacking of correlation between measured variables and predation regime might be due to the other concurrently changed environmental condition(e.g.food availability)which showed different effect on metabolism and behavior which dilute or mask the predation's effect on pale chub.