Animal Energetics, Volume 2: Bivalvia through Reptilia is part of a two-volume treatise focusing on the integrated picture of the energy transformation process at the organismic level. Since it is almost impossible to restrict meaningful discussions to only one level of organization, some reference is made to population energetics as well as to the suborganismic level. The bioenergetics of both vertebrate and invertebrate groups are discussed. Specifically, the bioenergetics of bivalves, gastropods, bryozoans, pogonophorans, echinoderms, lower chordates, fishes, amphibians, and reptiles are covered. Understanding the efficient and fast transformation of biological energy has become an important issue in world affairs; studies on energetics and growth of thermoconformers can therefore be expected to expand greatly in the future. This book aims to provide many keys to a broader understanding of biology as well as open untrodden avenues to biologists with the quest for newer energy sources and efficient methods of energy utilization.