Geckos are milking honeydew-producing planthoppers in Madagascar

In this paper we describe for the first time an extraordinary example of an interspecific trophobiotic relation between reptiles and planthoppers in Madagascar. Day gecko species of the genera Phelsuma and Lygodactylus as well as the nocturnal gecko Homopholis sakalava (Grandidier, 1867) show a particular behaviour that induces planthoppers of the family Flatidae to excrete a drop of honeydew in the course of an interspecific key stimulus reaction. Similar behaviour patterns are well known between ants and green flies or planthoppers, but have not been reported for vertebrates.     

运输方式互利共生的非线性动力学模型

综合运输结构决定综合运输系统的功能，各种运输方式之间的竞争和协作影响综合运输的结构。因此，研究各种运输方式的相互作用机制就显得很重要。本文通过对各种运输方式互利共生机制的研究，展示了各种运输方式协作互利的前景。仿真结果表明，如果各种运输方式的相对资源优势比较明显，就存在互利共生的可能性，并存在一个最优的合作水平。较高的资源转换效率和资源使用效率能使互利共生机制得到更充分的体现。与非合作动态博弈情况相比，协作情况下互利共生机制能发挥更大的作用。因此，通过政府部门等外力建立协作的机制，是更好地实现互利共生机制的必要前提。