Blackburn T M, Gaston K J
NERC Centre for Population Biology, Imperial College at Silwood Park, Berkshire, U.K.
Proc Biol Sci. 1994 Sep 22;257(1350):293-7. doi: 10.1098/rspb.1994.0128.
Frequency distributions of body size have been reported in the literature for a range of animal higher taxa. However, the reported shapes of these distributions may be biased by species missing from them, specifically by currently undiscovered species. There is a body of evidence that the small-bodied species in a taxon are described later, on average, than the large-bodied. From this, we predict that the means of animal body size frequency distributions should decrease through time, and the skewnesses of the distributions increase. These predictions are shown to be true for body size distributions for five different higher taxa of animals. Thus, any reported body size distribution for a taxon is likely to be systematically biased, even if it includes all the species which are known, if many species are likely to remain undiscovered.
文献中已经报道了一系列动物高级分类群的体型频率分布。然而，这些分布所报告的形状可能会受到其中缺失物种的影响，特别是目前尚未发现的物种。有大量证据表明，一个分类群中体型较小的物种平均而言比体型较大的物种被描述得更晚。据此，我们预测动物体型频率分布的均值会随着时间推移而降低，分布的偏度会增加。这些预测对于五种不同动物高级分类群的体型分布而言是成立的。因此，对于一个分类群所报告的任何体型分布都可能存在系统性偏差，即使它包括了所有已知物种，如果仍有许多物种可能未被发现的话。
