Download or read book Mammals written by Katharine Hall and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "All mammals share certain characteristics that set them apart from animal classes. But some mammals live on land and other mammals spend their lives in water--each is adapted to its environment. Land mammals breathe oxygen through nostrils but some marine mammals breathe through blowholes. Compare and contrast mammals that live on land to those that live in the water."--