INTRODUCTION
The dataset for hematocrit consists of two additional files. The numerical data for hematocrit are given in tabular form in the first file, consisting of 116 rows (species) and 6 columns. The second file contains a single reference from which the numerical hematocrit data were taken. Note that body weights were not given and hence are taken from the standardized body weight table  (See “The Design of Mammals. A Scaling Approach.’ Chapter 4).