Bell Graham
Biology Department, McGill University, 1205 Ave. Dr. Penfield, H3A 1B1, Montreal, Quebec, Canada.
Oecologia. 1983 Dec;60(3):378-383. doi: 10.1007/BF00376855.
The timing of the first two broods and the number and size of offspring in each was measured in a series of three experiments for monoclonal cultures of the cladoceran Daphnia pulex reared under standard conditions of ration, temperature and photoperiod. The pattern of total correlations between pairs of life-history variables did not in general support predictions made by hypotheses of reproductive cost. A partial correlation analysis, involving initial size and subsequent growth as well as the life history variables themselves, was performed in an attempt to avoid potential fallacies introduced by the use of total correlations. The only consistent effect found was a positive relationship between the age at reproductive maturity and the mean size of offspring in the first brood. The structure of this segment of the life history is strongly influenced by interactions between size and reproduction, to an extent that precludes the use of simple optimality models.
在一系列三个实验中，对在标准食物量、温度和光周期条件下饲养的枝角类大型蚤单克隆培养物，测量了前两窝的时间以及每窝后代的数量和大小。生活史变量对之间的总体相关模式一般不支持生殖成本假说所做的预测。进行了偏相关分析，涉及初始大小和后续生长以及生活史变量本身，以试图避免使用总体相关所引入的潜在谬误。唯一一致的效应是生殖成熟年龄与第一窝后代平均大小之间存在正相关关系。生活史的这一部分结构受到大小和繁殖之间相互作用的强烈影响，以至于无法使用简单的最优性模型。
