Abstract:
Functional signal in an interaction network is a phenomenon in which species resembling each other in their traits interact with similar partners. We tested the functional signal concept in realm-specific and regional flea-host networks from four biogeographic realms and asked whether the species composition of (a) host spectra and (b) flea assemblages is similar between functionally similar flea and host species, respectively. Analogously to testing for phylogenetic signal, we applied Mantel tests to investigate the correlation between flea or host functional distances calculated from functional dendrograms and dissimilarities in sets of interacting partners. In all realm-specific networks, functionally similar fleas tended to exploit similar hosts often belonging to the same genus, whereas functionally similar hosts tended to harbour similar fleas, again often belonging to the same genus. The strength of realm-specific functional signals and the frequency of detecting a significant functional signal in the regional networks differed between realms. The frequency of detecting a significant functional signal in the regional networks correlated positively with the network size for fleas and with the number of hosts in a network for hosts. A functional signal in the regional networks was more frequently found for hosts than for fleas. We discuss the mechanisms behind the functional signal in both fleas and their hosts, relate geographic functional signal patterns to the historic biogeography of fleas and conclude that functional signals in the species composition of host spectra for fleas and of flea assemblages for hosts result from the interplay of evolutionary and ecological processes.
摘要:
相互作用网络中的功能信号是一种现象,其中在性状上彼此相似的物种与相似的伴侣相互作用。我们测试了来自四个生物地理领域的特定领域和区域跳蚤宿主网络中的功能信号概念,并询问(a)宿主光谱和(b)跳蚤组合的物种组成在功能相似的跳蚤和宿主物种之间是否相似,分别。类似于测试系统发育信号,我们应用Mantel检验来研究从功能树状图计算出的跳蚤或宿主功能距离与相互作用伴侣组差异之间的相关性.在所有特定领域的网络中,功能相似的跳蚤倾向于利用通常属于同一属的相似宿主,而功能相似的寄主往往藏有相似的跳蚤,又经常属于同一属。领域特定功能信号的强度和在区域网络中检测重要功能信号的频率在领域之间有所不同。在区域网络中检测到重要功能信号的频率与跳蚤的网络大小以及主机网络中的主机数量呈正相关。主机比跳蚤更频繁地发现区域网络中的功能信号。我们讨论了跳蚤及其宿主中功能信号背后的机制,将地理功能信号模式与跳蚤的历史生物地理学联系起来,并得出结论,跳蚤宿主光谱和宿主跳蚤组合物种组成中的功能信号是进化和生态过程相互作用的结果。