Like the animals it describes, this book has had a long gestation. It started as a Ph.D. thesis on the white rhinoceros, grew into a monograph on rhinoceroses, expanded to include other similarly large herbivores, and then settled on the focus adopted in the pages that follow: the consequences of large size for the ecology of animals such as elephants, rhinoceroses and hippopotami, and by implication extinct species of similar size.

I hope that this work will be of interest to a variety of readers. Firstly, it is written for biologists interested in allometric scaling effects on ecological processes. The correlates of a body mass at the upper limit of the size range among mammalian herbivores are analyzed at various levels, including ecophysiology, behavioral ecology, demography, community interactions and ecosystem processes. Secondly, the book should be an aid to professional conservationists and wildlife managers concerned about the future survival of such large mammals. Scientific facts about these species must be given due cognizance if management actions are to achieve their desired objectives. Thirdly, it is directed towards paleobiologists interested in the ecological roles that similarly large mammals played in the faunas and ecosystems of the past. In particular potential causes of the extinctions of the so-called megafauna during the late Pleistocene are assessed. Finally, I hope that this book will be illuminating to all those who have marvelled at the ways of living of these largest among land animals, whether in the wild or on film.