Study Of The Call Competitive Strategy Of Male Anhui Tree Frog(Rhacophorus Zhoukaiyae)

In most amphibian species,vocal communication plays a crucial role in survival and reproductive success.Both male-male competition and female mate choice are almost totally dependent on vocal communication.Males dynamically optimize competitive strategies based on changes in various competitive factors including the number,ability,body size and temporal-spatial distribution of competitors.Previous studies have found that each component and temporal-spectral features of acoustic signals have distinct functions and biological significance in vocal communication.However,it remains unclear,how competitive strategies of males are modulated by different component and temporal-spectral features of calls.Consequently,in this thesis,the natural advertisement call and its altered versions were used in the male Anhui tree frogs(Rhacophorus zhoukaiyae)as subject to explore the influence of each component and temporal-spectral features of calls on male competitive strategies and the dynamics of male competitive strategies,using acoustic parameter analysis.1.In order to explore the influence of each component on male competitive strategies and the dynamics of competitive strategies,the natural advertisement calls(OC),the altered version with note 1 replaced by white noise(WN?N1),the altered version with note 5 replaced by white noise(WN?N5)and the altered version with note 1 replaced by note 5(N5?N1),were played back to the frogs.The acoustic parameters of the subjects' responsive calls including the number of calls,number of notes and call duration were recorded and analyzed.Results showed that:(1)there was no significant difference of acoustic parameters of responsive calls among the four types of stimuli,suggesting that each component of sounds had no significant influence on the male competitive strategy;(2)more non-overlapping calls were evoked compared with the overlapping calls,indicating that male competitive strategies were flexible.2.In order to explore the influence of temporal and spectral features on the competitive strategy and the dynamics of competitive strategies,OC and the two transformation versions including the version with white noise enveloped by the original note(only temporal characteristics remained,TC)and the version with each original note reversed(only spectral characteristics remained,SC),were played back to the animals.Results showed that:(1)the acoustic parameters were significantly higher than that during the control condition,although there was no significant difference of acoustic parameters among the three stimuli,suggesting that male competitive strategies were not affected by the temporal-spectral features of rivals' calls;(2)males emitted more non-overlapping calls compared with the overlapping calls;(3)for overlapping calls,the latencies with respect to OC and SC were significantly shorter than that to TC,indicating that males can discriminate the difference in temporal and spectral features,and spectral features may play more important roles in vocal communication;(4)the number of calls produced by the heavier subjects was greater than that by the lighter animals.Together,the above results suggested that the different component and temporalspectral features of conspecific calls had no significant influence on the male competitive strategy,but males adopted flexible competitive strategies to avoid call overlap.Furthermore,males can discriminate the difference in temporal and spectral features,and spectral features may play more important roles in vocal communication.In addition,males preferred to compete with weaker rivals.