Schoener Thomas W, Slade Jennifer B, Stinson Christopher H
Department of Zoology, University of California, 95616, Davis, CA, USA.
Department of Zoology, University of Washington, 98195, Seattle, WA, USA.
Oecologia. 1982 Jan;53(2):160-169. doi: 10.1007/BF00545659.
Over 5,000 prey items from specimens of Bahamian Leiocephalus lizards were measured and identified taxonomically. The diet in general consists mainly of arthropods, but much plant matter is also eaten, including flowers and buds as well as fruit. Lizards comprise about 2% of the diet by volume. Individuals inhabiting relatively small islands are more likely to have eaten plant matter than those from relatively large islands. Within the most widespread species (carinatus), sexual dimorphism in size is greater, the smaller the number of sympatric species in its structural habitat. Prey-size differences between differently sized Leiocephalus are greater, the greater the dimorphism. However, even the most dimorphic sexes take rather similar prey sizes. For all Bahamian species combined, the inverse correlation of sexual dimorphism with sympatric species is not as strong as an inverse correlation with latitude. We suggest that sexual selection on female size to increase the clutch size that can be carried may have affected sexual dimorphism in the genus.
对超过5000个巴哈马Leiocephalus蜥蜴标本的猎物进行了测量,并从分类学上进行了鉴定。总体而言,其饮食主要由节肢动物组成,但也会食用大量植物性物质,包括花朵、花蕾以及果实。蜥蜴在饮食中的占比约为2%(按体积计算)。栖息在相对小岛屿上的个体比来自相对大岛屿的个体更有可能食用植物性物质。在分布最广的物种(棱鳞Leiocephalus carinatus)中,其结构栖息地中的同域物种数量越少,体型上的两性异形就越大。不同体型的Leiocephalus之间猎物大小的差异越大,两性异形就越明显。然而,即使是两性异形最明显的性别,所捕食的猎物大小也相当相似。对于所有巴哈马物种而言,两性异形与同域物种的负相关关系不如与纬度的负相关关系那么强烈。我们认为,对雌性体型进行性选择以增加可携带的一窝卵数量,可能影响了该属的两性异形。