A New Biometrical Phase Character in Locusts
A New Biometrical Phase Character in Locusts
复制标题
蝗虫的新生物特征
作者：
V. M. Dirsh
同一种蝗虫的独居期和群集期可以通过颜色和生物统计学特征来区分。在后者中，通常使用鞘翅长度（E）与股骨后部长度（F）的比值E/F 2，但没有对各种测量值和比值的相对优点进行适当的统计研究。现在已经对沙漠蝗虫Schistocerca gregaria（Forsk.）的样本进行了身体所有适当部位的仔细测量，从一个非常低密度的野生种群（阶段solitaria），并从集群（阶段gregaria），和数据进行统计分析。由于两个阶段的频率分布多边形广泛重叠，因此对身体部位的20次直接测量中没有一次被证明是合适的。E/F比率也显示出重叠，使其使用不确定。此外，两个极端阶段的E值比较表明，根据阶段，两性的Elytron长度变化方向相反，因此：
THE solitary and the swarming phases of the same species of locusts can be distinguished by coloration and by biometrical characters1. Among the latter, the ratio E/F of the elytron length (E) to the posterior femur length (F) has been generally used2, but no proper statistical investigation of the relative merits of various measurements and ratios exists. Careful measurements of all suitable parts of the body have now been undertaken on samples of the desert locust, Schistocerca gregaria (Forsk.), taken from wild populations of a very low density (phase solitaria), and from swarms (phase gregaria), and the data analysed statistically. None of the twenty direct measurements of body parts proved to be suitable, as the frequency distribution polygons for the two phases overlapped widely. The E/F ratios also showed an overlap which made its use uncertain. Moreover, a comparison of E values in the two extreme phases showed that the elytron-length varied, according to the phase, in an opposite direction in the two sexes, thus: