Biology of Bryozoans

Biology of Bryozoans covers some of the unusual and even unique systems and aspects of bryozoans. The book discusses the gametogenesis of bryozoans; the brooding patterns of bryozoans; and the structure and classification of gymnolaemate larvae. The text also describes the metamorphosis, ancestrulae, and coloniality in bryozoan life cycles; the ultrastructure, mineralogy, and development of bryozoan skeletons; and polymorphism in marine bryozoans. Bryozoan feeding and culture; experimental techniques and culture methods; and the problem of the funiculi and the communications are also considered. The book further tackles the aging process in bryozoans; the bryozoan nervous system; and taxes and tropisms of bryozoans. The text also looks into the life strategies of bryozoans; the population genetics of bryozoans; and the adaptive model for the evolution of the ectoproct life cycle. Zoologists, marine biologists, and students taking related courses will find the book invaluable.

List of Contributors Preface 1 Gametogenesis of Bryozoans I. Morphology of the Ova and Oogenesis II. Morphology of the Spermatozoon and Spermiogenesis References 2 Brooding Patterns of Bryozoans I. Introduction II. Gymnolaemata III. Stenolaemata IV. Phylactolaemata V. Summarizing Comments on Brooding VI. Breeding Seasons References 3 Structure and Classification of Gymnolaemate Larvae I. Introduction II. Larval Structure III. Larval Types IV Conclusions References 4 Metamorphosis, Ancestrulae, and Coloniality in Bryozoan Life Cycles I. Introduction II. Gymnolaemata III. Cyclostomata IV. Phylactolaemata V. Summary References 5 Ultrastructure, Mineralogy, and Development of Bryozoan Skeletons I. Introduction II. Interpretation and Application of Skeletal Ultrastructure III . Stenolaemate Bryozoa IV. Cheilostome Bryozoa References 6 Polymorphism I. Some Elementary Definitions II. Distribution of Polymorphism among Bryozoans III. Types of Polymorphs: Generalities IV. Active Defense: Avicularia and Vibracula V. Cleaning: Nanozooids VI. Passive Defense: Spinozooids VII. Colony Strengthening: Intercalated and Marginal Kenozooids VIII. Colony Support: Rhizozooids, Stylozooids, and Stolons (?) IX. Survival of Unfavorable Conditions: Rhizozooids and Stolons, Hibernacula, Statoblasts, and Sacculi X. Interzooidal Connections: Interzooids XI. Sexual Reproduction: Gonozooids XII. From Free to Sedentary Life: Ancestrulae XIII. Induction and Origin of Polymorphism: Generalities XIV. The Individual Concept XV. Ontogenetic Development of Polymorphs XVI. Substitution of Different Polymorphs XVII. Conditions Inducing Polymorphism XVIII. Origin and Evolution of Polymorphism References 7 Feeding in Marine Bryozoans I. Introduction II. Review of Functional Morphology of Feeding III . Variation in the Bryozoan Polypide IV. Bryozoan Feeding and Culture V. General Discussion VI. Suggestions for Future Research VII. Conclusions References8 Experimental Techniques and Culture Methods I. Introduction II. Experimental Work in the Field III. Simple Rearing in the Laboratory IV. General Conditions for Laboratory Work V. Cultivation or Long-Term Rearing References 9 Interzooecial Communications and the Funicular System I. Introduction II. Case of the Phylactolaemates III. Case of Eurystome Gymnolaemates IV. Case of Cyclostome Gymnolaemates V. Conclusions References10 The Aging Process in Bryozoans I. Introduction II. General Features III. Ultrastructural Features of Regression IV. The Fate of the Brown Body V. Distribution of Cyclic Regression and Regeneration VI. Cause and Effect of Brown Body Formation VII. Summary References 11 The Bryozoan Nervous System I. Introduction II. General Anatomy III. The Interzooidal Information Hypothesis IV. Discussion V. Summary References 12 Taxes and Tropisms of Bryozoans I. Introduction II. Orientation Responses of Free-Swimming Larvae and Motile Colonies III. Orientation Responses of Settling Larvae IV. Orientation Responses of Fixed Colonies V. Summary References 13 Fouling and Bioadhesion: Life Strategies of Bryozoans I. Introduction II. Reproductive Strategies III. Bioadhesives and Attachment IV. Fouling Communities V. Fouling Colonial Strategies References 14 Population Genetics of Bryozoans I. Introduction II. Population Size III. Outbreeding and Inbreeding IV. Linkage V. Geographic Variation VI. Genetic Variability VII. Implications for Speciation VIII. Appendix: Summary of Techniques IX. Addendum References 15 An Adaptive Model for the Evolution of the Ectoproct Life Cycle I. Introduction II. The Ground Plan Concept and Its Bearing on the Origin of Phyla III. The Position of the Ectoprocta in Lophophorate Phylogeny IV. General Features of the Phoronida and Ectoprocta V. The Adaptive Basis of Morphological Differences in the Adult Stage of Phoronids and Ectoprocts VI. A Model for the Origin of the Adult Features of the Ectoproct Ground Plan VII. Historical Evidence Bearing on the Model VIII. The Viability of Intermediate Modes of Life IX. Evolution of the Larval Stage of the Life Cycle X. The Actinotroch Larva of the Phoronida XI. Larval Development in the Ectoprocta XII. The Cyphonautes Larva XIII. Discussion and Conclusions References 16 Phylogenetic Considerations: The Protostomian Relationships I. Introduction II. The Relationship between Entoprocts and Ectoprocts III. Discussion of Possible Relationships with the Phoronids IV. The Relationships of the Bryozoans (Entoprocts + Ectoprocts) References Appendix Index