Helmus Matthew R, Savage Kristina, Diebel Matthew W, Maxted Jeffrey T, Ives Anthony R
Department of Zoology, University of Wisconsin, Madison, WI 53706, USA.
Ecol Lett. 2007 Oct;10(10):917-25. doi: 10.1111/j.1461-0248.2007.01083.x.
The role of competition in forbidding similar species from co-occurring has long been debated. A difficulty in identifying this repulsion of similar species is that similar species share similar environmental requirements and hence show an attraction to communities where these requirements are met. To disentangle these opposing patterns, we use phylogenetic relatedness as an objective metric of species similarities. Studying 11 sunfishes (Centrarchidae) from 890 lakes, we first show no phylogenetic pattern in the raw community data. We then regressed sunfish presence/absence against seven environmental variables and show that lakes with similar water clarity and latitude likely contain closely related species. After statistically removing the environmental effects, phylogenetic repulsion was apparent, with closely related sunfishes less likely to co-occur. Thus, both phylogenetic attraction, driven by environmental filtering, and phylogenetic repulsion, possibly caused by competition, simultaneously occur and obscure one another in the overall phylogenetic structure of sunfish communities.
竞争在阻止相似物种共存方面所起的作用长期以来一直存在争议。识别相似物种间这种排斥现象的一个难点在于，相似物种具有相似的环境需求，因此会被满足这些需求的群落所吸引。为了厘清这些相反的模式，我们将系统发育相关性作为物种相似性的客观指标。通过研究来自890个湖泊的11种太阳鱼（鲈形目太阳鱼科），我们首先发现原始群落数据中不存在系统发育模式。然后，我们将太阳鱼的存在与否与七个环境变量进行回归分析，结果表明，水透明度和纬度相似的湖泊可能包含亲缘关系较近的物种。在通过统计方法消除环境影响后，系统发育排斥现象变得明显，亲缘关系较近的太阳鱼不太可能同时出现。因此，由环境过滤驱动的系统发育吸引和可能由竞争导致的系统发育排斥，在太阳鱼群落的整体系统发育结构中同时发生且相互掩盖。
