Kingston T, Jones G, Zubaid A, Kunz T H
Department of Biology, Boston University, Boston, MA 02215, USA Fax: +1-617-3535383, , , , , , US.
School of Biological Sciences, University of Bristol, Woodland Road, Bristol, BS8 1UG, UK, , , , , , GB.
Oecologia. 2000 Aug;124(3):332-342. doi: 10.1007/PL00008866.
We assessed the ecomorphological structure of a guild of rhinolophoid bats in a Malaysian rainforest first described by Heller and von Helversen (1989). These authors found that the distribution of echolocation call frequencies used by 12 syntopic species was more even than expected from allometric relationships or in randomly generated communities, and that the observed minimal ratio was greater than expected by chance alone. In this study we were able to expand their guild to 15 species, but in doing so it became apparent that call frequencies might be less evenly distributed across the total frequency range than previously proposed. We replicated Heller and von Helversen's (1989) analyses with the full 15-species complement but were unable to support their suggestion that rhinolophoid bats exhibit resource partitioning through differences in frequency bands. We adopted a multivariate approach and incorporated measures of body size and wing morphology into the analysis. We used phylogenetic autocorrelation to ensure that the species were statistically independentand principal component analysis to describe the morphological space occupied by the 15 species in the community and four additional species representing the extremes of phenotypic variation. We derived interspecific Euclidean distances and tested the mean values and SDs of these distances against those of 100 guilds of "synthetic" species created randomly within the principal component space. The guild of Rhinolophoidea was not distributed randomly in multivariate space. Instead we found evidence of morphological overdispersion of the most similar species, which suggests niche differentiation in response to competition. Less similar species were nearer in morphological space than expected, and we suggest this is a consequence of ecological constraints on parameter combinations. Despite this underdispersion, many of the more distant neighbours were evenly rather than randomly spaced or clumped in morphospace, suggesting that, given the environmental constraints on morphology, species in this guild do experience limits to their similarity. Finally, we tested the influence of the relative abundance of species on morphological displacement, and found no evidence that abundant, spatially correlated species reduce interspecific overlap in morphological space.
我们评估了马来西亚雨林中一组菊头蝠科蝙蝠的生态形态结构，该组蝙蝠最初由赫勒和冯·赫尔弗森（1989年）描述。这些作者发现，12种同域分布物种所使用的回声定位叫声频率分布比根据异速生长关系或在随机生成的群落中预期的更为均匀，并且观察到的最小比率大于仅由偶然因素导致的预期值。在本研究中，我们能够将他们所研究的蝙蝠组扩展到15个物种，但这样做时很明显，叫声频率在整个频率范围内的分布可能不如先前提出的那样均匀。我们用完整的15个物种组合重复了赫勒和冯·赫尔弗森（1989年）的分析，但无法支持他们关于菊头蝠科蝙蝠通过频带差异表现出资源分配的观点。我们采用了多变量方法，并将体型和翅膀形态的测量纳入分析。我们使用系统发育自相关来确保物种在统计上是独立的，并使用主成分分析来描述群落中15个物种以及代表表型变异极端情况的另外4个物种所占据的形态空间。我们得出种间欧氏距离，并将这些距离的平均值和标准差与在主成分空间内随机创建的100个“合成”物种组的距离进行比较。菊头蝠科在多变量空间中并非随机分布。相反，我们发现了最相似物种形态过度分散的证据，这表明对竞争的生态位分化。不太相似的物种在形态空间中的距离比预期更近，我们认为这是生态对参数组合的限制的结果。尽管存在这种分布不足，但许多距离较远的近缘物种在形态空间中是均匀分布而不是随机分布或聚集分布，这表明，鉴于环境对形态的限制，该组中的物种在相似性方面确实存在限制。最后，我们测试了物种相对丰度对形态替代的影响，没有发现证据表明丰富的、空间相关的物种会减少形态空间中的种间重叠。
