On the Relative Importance of Body Weight and Surface Area Measurements for the Prediction of the Level of Oxygen Consumption of Ligia Oceanica L. And Prepupae of Drosophila Melanogaster Meig

Abstract

1. Previous investigations with Ligia oceanica and prepupae of Drosophila melanogaster (Ellenby, 1951, 1953) have suggested that it may be possible to predict the level of oxygen consumption more precisely from a measurement of surface area (Drosophila) or body length (Ligia) than from body weight, in spite of the greater accuracy of the latter measurement. The point is now examined more closely by applying the technique of multiple regression to the original data. 2. For Ligia, it is shown that the suggestion cannot be upheld, for the level of oxygen consumption can be predicted with greater accuracy from body weight than from a function of body length. 3. On the other hand, for diploid male and female prepupae of Drosophila, it is shown that surface area does, in fact, give a better prediction than body weight. In the case of triploid female prepupae, however, body weight is superior. 4. It is shown that there are no grounds for believing that the measurements of surface area were less accurate in the case of the triploids; for this and other reasons, it is suggested that the difference between diploids and triploids may be due to a fundamental difference between the two sorts of prepupae.