Pygmy hippopotamus unusual secretion as common hippos, that gives a pinkish tinge to their bodies, and is sometimes described as "blood sweat" though the secretion is neither sweat nor blood. This substance, hipposudoric acid, is believed to have antiseptic and sunscreening properties. The skin of hippos dries out quickly and cracks, which is why both species spend so much time in water. The skeleton of "C. liberiensis" is more gracile than that of the common hippopotamus, meaning their bones are proportionally thinner. The common hippo's spine is parallel with the ground; the pygmy hippo's back slopes forward, a likely adaptation to pass
Mammal Species of the World Mammal Species of the World Mammal Species of the World: A Taxonomic and Geographic Reference is a standard reference work in mammalogy giving descriptions and bibliographic data for the known species of mammals. It is now in its third edition, published in late 2005, which was edited by Don E. Wilson and DeeAnn M. Reeder. An online version is hosted by Bucknell University, from which the names of the species can be downloaded as a custom dictionary. A partial online version is available at Google Books (see "External links" below). The Checklist Committee is charged with compiling and updating MSW.