Magrath Robert D, Bennett Thomas H
Division of Evolution, Ecology and Genetics, Research School of Biology, Australian National University, Canberra 0200, Australia.
Proc Biol Sci. 2012 Mar 7;279(1730):902-9. doi: 10.1098/rspb.2011.1362. Epub 2011 Aug 17.
Many vertebrates eavesdrop on alarm calls of other species, which is a remarkable ability, given geographical variation in community composition and call diversity within and among species. We used micro-geographical variation in community composition to test whether individuals recognize heterospecific alarm calls by: (i) responding to acoustic features shared among alarm calls; (ii) having innate responses to particular heterospecific calls; or (iii) learning specific alarm calls. We found that superb fairy-wrens (Malurus cyaneus) fled to cover to playback of noisy miner (Manorina melanocephala) aerial predator alarm calls only in locations where miners were present, suggesting that learning rather than acoustic structure determines response. Sites with and without miners were well within the dispersal distance of fairy-wrens, and philopatric males and dispersing females showed the same pattern, so that local genetic adaptation is extremely unlikely. Furthermore, where miners were present, fairy-wrens responded appropriately to different miner calls, implying eavesdropping on their signalling system rather than fleeing from miners themselves. Learned eavesdropping on alarm calls enables individuals to harvest ecologically relevant information from heterospecifics on an astonishingly fine spatial scale. Such phenotypic plasticity is valuable in a changing world, where individuals can be exposed to new species.
许多脊椎动物会偷听其他物种的警报叫声，考虑到群落组成的地理差异以及物种内部和物种之间叫声的多样性，这是一种非凡的能力。我们利用群落组成的微观地理差异来测试个体是否通过以下方式识别异种警报叫声：（i）对警报叫声中共享的声学特征做出反应；（ii）对特定的异种叫声有先天反应；或（iii）学习特定的警报叫声。我们发现，华丽细尾鹩莺（Malurus cyaneus）只有在有吵闹矿工鸟（Manorina melanocephala）的地方才会在播放吵闹矿工鸟的空中捕食者警报叫声时逃到隐蔽处，这表明是学习而非声学结构决定了反应。有矿工鸟和没有矿工鸟的地点都在细尾鹩莺的扩散距离之内，留巢的雄性和扩散的雌性表现出相同的模式，因此极不可能是局部基因适应。此外，在有矿工鸟的地方，细尾鹩莺对不同的矿工鸟叫声做出了适当反应，这意味着它们是在偷听其信号系统而不是逃离矿工鸟本身。通过学习偷听警报叫声，个体能够在惊人精细的空间尺度上从异种那里获取与生态相关的信息。这种表型可塑性在一个不断变化的世界中很有价值，在这个世界里，个体可能会接触到新的物种。
