Terblanche John S, White Craig R, Blackburn Tim M, Marais Elrike, Chown Steven L
Centre for Invasion Biology, Stellenbosch University, Private Bag X1, Matieland 7602, Republic of South Africa.
Biol Lett. 2008 Feb 23;4(1):127-9. doi: 10.1098/rsbl.2007.0522.
Previously, it has been suggested that insect gas exchange cycle frequency (fC) is mass independent, making insects different from most other animals where periods typically scale as mass-0.25. However, the claim for insects is based on studies of only a few closely related taxa encompassing a relatively small size range. Moreover, it is not known whether the type of gas exchange pattern (discontinuous versus cyclic) influences the fC-mass scaling relationship. Here, we analyse a large database to examine interspecific fC-mass scaling. In addition, we investigate the effect of mode of gas exchange on the fC-scaling relationship using both conventional and phylogenetically independent approaches. Cycle frequency is scaled as mass(-0.280) (when accounting for phylogenetic non-independence and gas exchange pattern), which did not differ significantly from mass(-0.25). The slope of the fC-mass relationship was shallower with a significantly lower intercept for the species showing discontinuous gas exchange than for those showing the cyclic pattern, probably due to lower metabolic rates in the former. Insects therefore appear no different from other animals insofar as the scaling of gas exchange fC is concerned, although gas exchange fC may scale in distinct ways for different patterns.
此前有人提出，昆虫的气体交换循环频率（fC）与质量无关，这使得昆虫不同于大多数其他动物，在其他动物中，周期通常与质量的-0.25次方成比例。然而，关于昆虫的这一说法是基于对少数几个亲缘关系密切的类群的研究，这些类群的大小范围相对较小。此外，尚不清楚气体交换模式的类型（间断型与循环型）是否会影响fC与质量的比例关系。在这里，我们分析了一个大型数据库，以研究种间fC与质量的比例关系。此外，我们使用传统方法和系统发育独立方法，研究了气体交换模式对fC比例关系的影响。循环频率与质量的-0.280次方成比例（在考虑系统发育非独立性和气体交换模式时），这与质量的-0.25次方没有显著差异。与表现出循环气体交换模式的物种相比，表现出间断气体交换的物种的fC与质量关系的斜率更平缓，截距显著更低，这可能是由于前者的代谢率较低。因此，就气体交换fC的比例关系而言，昆虫似乎与其他动物没有什么不同，尽管不同模式的气体交换fC可能以不同的方式成比例。
