Museum of Vertebrate Zoology Collections - Searchable database of specimens that includes over 50,000 tissue samples for use in molecular analyses. Phylum Hemichordata, Urochordata and Cephalochordata - Illustrated description of these three phyla, and the three classes within Urochordata. Also information on the larval stages which form part of the plankton. Will's Skull Page - Features images and measurements of mammalian skulls as well as updates and related links. The Vertebrates - Notes on the classification structure of the Vertebrates with a cladogram to review the evolutionary relationships of the craniata. Invertebrate Members of the Phylum Chordata - Outlines the differences between the subphylum Vertebrata and the two subphyla, Urochordata and Cephalochordata. Other Animal Sounds - Clips recorded by Doug Von Gausig of the sounds made by various amphibians, reptiles, mammals and birds. The Annual Symposium of Vertebrate Palaeontology and Comparative Anatomy - Details of this year’s meeting of SVPCA and abstracts from presentations made in previous years. Terrestrial Vertebrates - Describes the principle characteristics of tetrapods, which have well defined joints and digits, their classification and phylogenetic relationships. Hearing in Stegocephalians - In this article, Michael Laurin outlines the anatomy and evolution of the outer, middle and inner ear in land vertebrates. Phylogeny of Stegocephalians - Stegocephalians are tetrapods with digits rather than fins. Michael Laurin explores the relationship between the extant and the extinct members of this group. Life History of Stegocephalians - Michael Laurin outlines the life history of tetrapods and extinct terrestrial vertebrates. Breathing in Stegocephalians - Most tetrapods breathe with the lungs that they inherited from their ancestors such as the coelacanth and lungfishes and this is probably also true of extinct groups of stegocephalians. Anatomical Terms of Location - Article from Wikipedia describing the complex terminology necessary to be used when describing the anatomy of animals in order to avoid confusion. Bone - Article from Wikipedia describing the characteristics, functions and types of bone and how bone is formed. Department of Vertebrate Zoology - Information on the research and programs being undertaken at the Smithsonian Museum of Natural History. Sensory Systems in Amphioxus: A Window on the Ancestral Chordate Condition - Abstract from a paper comparing the sensory systems of vertebrates with the less-developed systems of Amphioxus. Chordata - Information on the invertebrate members of the phylum Chordata, what they have in common, and the characteristics of the two subphyla, Urochordata and Cephalochordata. Infrared Zoo - Uses infrared photography to show the differences between warm and cold blooded animals. Cornell University Museum of Vertebrates - Educational and research resource with sections on ichthyology, herpetology, ornithology and mammalogy. PetEducation.com: Cardiovascular System: The Heart and Vessels - Outlines the function of this system, its anatomy and physiology, and compares the mammalian organs with those of birds, amphibians, reptiles and fish. Guide to Animal Sounds on the Net - Provides an index to animal sounds on the Web including birds, mammals, reptiles, amphibians, fish and insects. BioMed Central: Molecular Patterns of Sex Determination in the Animal Kingdom - Abstract from an article studying a variety of regulatory mechanisms that determine the sex of offspring in the animal kingdom. California Academy of Sciences: Skull Stories - Though primarily designed to protect the brain, the architecture of an animal’s skull can help scientists to deduce many of its dietary and social patterns. Palaeos: The Vertebrates - Glossary - Provides a comprehensive list of definitions of the technical terms likely to be met when studying the vertrebates. The Integument and its Derivatives - These notes cover the dermis and epidermis including skin, beaks, nails, hooves, horns, hair, feathers, scales and teeth. Animal Cells and Tissues - Notes by Michael J. Farabee on the structure and functions of each of the four major animal tissue types: epithelial, muscle, connective and bone. Animal Organ Systems and Homeostasis - Homeostasis describes the physical and chemical parameters that an organism must maintain to allow proper functioning of its component cells, tissues and organs. Biological Diversity: Animals - Outlines the evolutionary history of animal groups from the simple coelomates to the chordates and the various vertebrate classes, with diagrams and photographs. Online Biology Book: Glossary - Comprehensive list of the technical terms you are likely to come across, with cross references.