马铁菊头蝠幼蝠能够辨别种群间回声定位声波差异

The Juveniles of Greater Horseshoe Bats Can Discriminate the Difference of Echolocation Calls from Different Populations

蝙蝠的回声定位声波普遍存在地理变化,然而尚不清楚幼蝠在扩散前能否辨别不同种群间的声波差异。本文采用"双选择声学回放实验",研究马铁菊头蝠(Rhinolophus ferrumequinum)幼蝠(1月龄)对回声定位声波地理变化的辨别能力及行为反应。采用4个行为参数衡量幼蝠对本种群(CC)与外种群(JN)回声定位声波的行为反应:每一回放室飞入的次数、飞行时间、停留次数、探测时间。Mann-Whitney U tests表明,马铁菊头蝠1月龄个体对回放声波的行为反应,除每一回放室停留的次数外,其他3个参数均存在显著差异(P<0.05),且在本种群声波回放室(CC)的飞行次数和时间以及探测时间均高于外种群声波回放室(JN)。对4个行为参数进行主成分分析,Mann-Whitney U tests表明,回放本种群声波(CC)与外种群声波(JN)之间,第一主成分得分(PC1)存在显著差异(P<0.01)。配对T检验表明,幼蝠对本种群声波反应更加强烈(PC1:t10=5.25,P<0.001;PC2:t10=2.34,P<0.05)。本研究说明马铁菊头蝠幼蝠能够辨别不同种群间回声定位声波的差异。

The geographical variation in bat echolocation calls is common. However, it is not clear whether juveniles of bats are able to discriminate the echolocation differences between populations before the juveniles＇ diffusion. In this study, we used two-choice playback experiments to detect the discrimination ability and behavioural response of juveniles （one-month old） to geographical variation in echolocation calls of the Greater Horseshoe Bats （Rhinolophusferrumequinum）. We used four response parameters to measure the behaviour of juveniles towards to either local or foreign echolocation calls： number of flights, time spent in flight, number of landings, and time spent in detection. The result showed that there was a significant difference in number of flights, time spent in flight and time spent in detection by Mann-Whitney U test （P 〈 0.05）, but no any significant difference in number of landings （Fig. 2） was detected. Overall, the juveniles flew more often and spent more time in flying to detect the calls made by local population than those made by the foreign populations （Fig. 2, Table 1）. We performed a principal component analysis for the four response parameters of juveniles and found out that there were statistically significant differences in the PC1 scores between playback treatments （P 〈 0.01） for the result of Mann-Whitney U tests. The juveniles responded more strongly to local than to foreign echolocation calls （PC1 ： t10 = 5.25, P 〈 0.001; PC2：t10 = 2.34, P 〈 0.05） by the paired samples Student＇s t tests. This study showed that the juveniles of the Greater Horseshoe Bats was capable to discriminate the acoustic difference between their own population and other population.