An original new science series which explores the key characteristics that divide the main animal and plant groups, and looks at how these characteristics have evolved over time. The information is supported by examples that highlight the quirky and amazing qualities of the natural world, as well as revealing the dazzling variety within each group. Why Do Mammals Have Fur? looks at the defining features of mammals, such as being warm-blooded, having hair and feeding their young, and explores how mammals have evolved and adapted over time. Mammal life cycles, behaviour and habitats all also feature.