Hippos are unusual in being genuinely amphibious and this has a fundamental effect on their physiology and way of life. Following a general introduction, there is a detailed description of hippo anatomy and physiology, including many fascinating and little known facts about their skin structure and physiology. The complex question of hippo stomach anatomy, and its impact on their diet and nutrition, is critically reviewed. Hippos have a four-chambered stomach similar to ruminants although, unlike them, they do not chew the cud. Hence they are often called "pseudoruminants". The fossil history of hippos is then considered and the recently claimed relationship with whales is examined. Subsequent chapters are devoted to their social biology and ecology, including descriptions of their breeding and feeding ecology. Several extraordinary instances of carnivory, including an instance of cannibalism, are described. A chapter on diseases and parasites also discusses the relations between hippos and other species, including crocodiles, to which they appear to be dominant. A consideration of the hippo"s relationships with its human neighbours and the prospects for its long-term conservation gives an important view of current conservation concerns. The book closes with three chapters devoted to the results of the author"s recent survey on the distribution and abundance of the common hippo throughout Africa. This is the first such estimate to have been made on a continent-wide basis and the total population of about 170,000 was so much smaller than many people had expected, that it resulted in the common hippo being given special protection under the CITES convention. Key Features * The first complete work on both species of hippo, the river hippo and the pygmy hippo * Much of its data is drawn from the author"s experiences while completing the IUCN Hippo Plan throughout Africa and in Uganda in particular * All aspects of hippo biology are covered * There has been no previous in depth study of the ecology and behaviour of these mammals before