Caecilians, or Gymnophiona, constitute one of the three extant orders of the Recent Amphibia and comprise about 170 named species in six families. They are the least known, major living tetrapod clade. Compared to frogs and salamanders, caecilians have an unusual skull morphology. With few exceptions, previous studies on caecilian morphology have been restricted to investigations on adult material and were usually carried out on small samples. This thesis investigates skull development in caecilians. Earlier reports of an unusually high number of individual skull ossifications in Hypogeophis rostratus are addressed and found to be erroneous. Changes in skull morphology and myology at metamorphoses are investigated in representatives of all taxa possessing free-living larvae. It is argued that caecilians are derived from gymno- or zygokrotaphic ancestors and that stegokrotaphy evolved within Recent caecilians. To investigate the influence of different life-histories, postembryonic skull development was studied in two direct-developing species. The direct-developing Boulengerula taitanus is characterized by very immature hatchlings, which is correlated with an extended period of post-hatching parental care in this species, during which juveniles feed on the modified stratum corneum of their mothers. Direct development in caecilians is characterized by ontogenetic repatterning and heterochronic shifts in certain developmental events. The ontogeny of Scolecomorphus kirkii was studied as a representative of a viviparous form. The emerging picture of available published information, together with observations presented here, suggest a previously unsuspected degree of developmental diversity among caecilians. It is further argued that caecilians are lissamphibians with temnospondyl affinities rather than closely related to lepospondyl microsaurs.

The evolution of vertebrate hearing is of considerable interest in the hearing community. However, there has never been a volume that has focused on the paleontological evidence for the evolution of hearing and the ear, especially from the perspective of some of the leading paleontologists and evolutionary biologists in the world. Thus, this volume is totally unique, and takes a perspective that has never been taken before. It brings to the fore some of the most recent discoveries among fossil taxa, which have demonstrated the sort of detailed information that can be derived from the fossil record, illuminating the evolutionary pathways this sensory system has taken and the diversity it had achieved.

Describes the latest methodologies used to study the ecology of amphibians throughout the world. Each of the 27 chapters explains a research approach or technique, with emphasis on careful planning and the potential biases of techniques. Statistical modelling, landscape ecology, and disease are covered for the first time in a techniques handbook.

Through its emphasis on recent research, its many summary tables, and its bibliography of more than 4,000 entries, this first modern, synthetic treatment of comparative amphibian environmental physiology emerges as the definitive reference for the field. Forty internationally respected experts review the primary data, examine current research trends, and identify productive avenues for future research.

A classic problem in evolutionary biology is the origin of larvae - how and why did they occur? Indeed, it has often been suggested that many entirely unique body plans first originated as retained larvae of ancestral organisms. But what of the larvae themselves? What developmental and evolutionary forces shape and constrain them? These questions and others are dealt with by this international team of leading zoologists and developmental biologists. Intended to contribute to a continuing dialectic, this book presents diverse opinions as well as manifold conclusions. Certain to challenge and intrique, The Origin and Evolution of Larval Forms should be a part of the library of every evolutionary and developmental biologist interested in larvae and their significance.

This book provides students and researchers with reviews of biological questions related to the evolution of feeding by vertebrates in aquatic and terrestrial environments. Based on recent technical developments and novel conceptual approaches, the book covers functional questions on trophic behavior in nearly all vertebrate groups including jawless fishes. The book describes mechanisms and theories for understanding the relationships between feeding structure and feeding behavior. Finally, the book demonstrates the importance of adopting an integrative approach to the trophic system in order to understand evolutionary mechanisms across the biodiversity of vertebrates.

Herpetology, Second Edition has been thoroughly revised. The text has been reorganized, new chapters have been added, new text references have been inserted. All this plus new color systematics sections will maintain this book as THE leading textbook on the biology of amphibians and reptiles. The book will also showcase reptiles and amphibians as model systems in conceptual areas of biology. Such a text will help integrate herpetology as a discipline into conceptually oriented undergraduate programs. The book should also appeal to a large audience of sophisticated lay people interested in reptiles and amphibians. - Written by internationally recognized experts on the biology of amphibians and reptiles - Provides a general background on the evolution and morphology of amphibians and reptiles - Details what is known about reproduction and life histories - Examines physiological ecology, emphasizing water balance, temperature, and energy - Integrates population and community ecology with conservation biology - Provides detailed taxonomic accounts of all higher taxa, including high quality distribution maps and color photographs