xxiii
the Cheilostomata during their history. The results of this study indicate that the evolutionary
success of Cheilostomata may have been based on changes in sexual reproduction, namely, the
evolution of new reproductive strategies and patterns involving the origin of parental care.
Importantly, the complex approach applied during this study was instrumental in revealing
numerous examples of parallelisms and convergent evolution. The large suite of new data on
bryozoan reproduction was also useful for understanding trends in the evolution of sexual
reproduction in marine invertebrates in general.
The monograph consists of three chapters. The fi rst chapter is devoted to comparative analysis of reproductive patterns in Bryozoa: fi rst of all, oogenesis, fertilization and brooding in the
Cheilostomata. Detailed consideration is given to the position of gonads, the sexual structure
of the colonies, sexual polymorphism and oviposition. The second chapter deals with the structural diversity, independent origin and evolution of brood chambers in different cheilostome
groups. These two chapters are mostly based on the results of original research, which is compared with information in the literature. The third chapter contains an analysis of the main
directions in the evolution of sexual reproduction in bryozoans and a reconstruction of the
stages: changes in modes of oogenesis and fertilization and their consequences, the transition
to the non-feeding larva, the origin of embryonic incubation, and repeated evolution of matrotrophy and placental analogues. The trends that emerge from this analysis are compared with
analogues in the evolution of the bryozoan order Ctenostomata as well as other marine invertebrate groups (predominantly, echinoderms, molluscs and annelids). The conditions under
which the cheilostomes radiated in the Late Cretaceous are considered in detail, and the consequences of the transitions to new reproductive patterns are analyzed. Finally, the stages in the
evolution of sexual reproduction in other bryozoan groups (classes Phylactolaemata and
Stenolaemata) are reconstructed. The monograph contains 12 tables, including those with data
on the sexual structure of colonies, the position of gonads in zooids and the size and number
of the oocytes at various stages of development, embryonic increase during incubation, etc., as
well as a review of the history of study of sexual reproduction in the Gymnolaemata with a list
of the species studied. This review also references the major publications on bryozoan life
cycles, which are not analyzed in the main body of the text.
The fi rst version of this monograph was published by the Publishing House of Saint
Petersburg State University (Unipress) in 2009 under the title “Evolution of sexual reproduction in the bryozoan order Cheilostomata (Gymnolaemata)” (Ostrovsky 2009). Since that time,
new data emerged that led to a critical reassessment of some parts of the book. As a result the
text of the present English edition has been considerably rewritten and supplemented. In particular, bryozoan reproduction is compared throughout the monograph with that in other
aquatic invertebrates. These changes called for a change in the title of the book.
References
Abouheif E, Zardoya R, Meyer A (1998) Limitations of metazoan 18s RNA sequence data: implications for
reconstructing a phylogeny of the animal kingdom and inferring the reality of the Cambrian explosion. J
Mol Evol 47:394–405
Adiyodi KG, Adiyodi RG (eds) (1983) Reproductive biology of invertebrates, vol 1. Oogenesis, oviposition,
and oosorption. John Wiley and Sons, Chichester
Adiyodi KG, Adiyodi RG (eds) (1989) Reproductive biology of invertebrates, vol 4. Part A: fertilization, development, and parental care. IBH Publishing Co Pvt Ltd, New Delhi/Bombay/Calcutta/Oxford
Adiyodi KG, Adiyodi RG (eds) (1990) Reproductive biology of invertebrates, vol 4. Part B: fertilization, development, and parental care. IBH Publishing Co Pvt Ltd, New Delhi/Bombay/Calcutta/Oxford
Allman G (1856) A monograph of the fresh-water Polyzoa, including all the known species, both British and
foreign. Ray Society, London
Anderson DT (2001) Invertebrate zoology. Oxford University Press, Oxford
Anstey RL (1990) Bryozoans. In: McNamara KJ (ed) Evolutionary trends. University of Arizona Press, Tucson,
pp 232–252
Anstey RL, Pachut JF (1995) Phylogeny, diversity history and speciation in Paleozoic bryzoans. In: Erwin DH,
Anstey RL (eds) New approaches to speciation in the fossil record. Colombia University Press, New York,
pp 239–284
Introduction
the Cheilostomata during their history. The results of this study indicate that the evolutionary
success of Cheilostomata may have been based on changes in sexual reproduction, namely, the
evolution of new reproductive strategies and patterns involving the origin of parental care.
Importantly, the complex approach applied during this study was instrumental in revealing
numerous examples of parallelisms and convergent evolution. The large suite of new data on
bryozoan reproduction was also useful for understanding trends in the evolution of sexual
reproduction in marine invertebrates in general.
The monograph consists of three chapters. The fi rst chapter is devoted to comparative analysis of reproductive patterns in Bryozoa: fi rst of all, oogenesis, fertilization and brooding in the
Cheilostomata. Detailed consideration is given to the position of gonads, the sexual structure
of the colonies, sexual polymorphism and oviposition. The second chapter deals with the structural diversity, independent origin and evolution of brood chambers in different cheilostome
groups. These two chapters are mostly based on the results of original research, which is compared with information in the literature. The third chapter contains an analysis of the main
directions in the evolution of sexual reproduction in bryozoans and a reconstruction of the
stages: changes in modes of oogenesis and fertilization and their consequences, the transition
to the non-feeding larva, the origin of embryonic incubation, and repeated evolution of matrotrophy and placental analogues. The trends that emerge from this analysis are compared with
analogues in the evolution of the bryozoan order Ctenostomata as well as other marine invertebrate groups (predominantly, echinoderms, molluscs and annelids). The conditions under
which the cheilostomes radiated in the Late Cretaceous are considered in detail, and the consequences of the transitions to new reproductive patterns are analyzed. Finally, the stages in the
evolution of sexual reproduction in other bryozoan groups (classes Phylactolaemata and
Stenolaemata) are reconstructed. The monograph contains 12 tables, including those with data
on the sexual structure of colonies, the position of gonads in zooids and the size and number
of the oocytes at various stages of development, embryonic increase during incubation, etc., as
well as a review of the history of study of sexual reproduction in the Gymnolaemata with a list
of the species studied. This review also references the major publications on bryozoan life
cycles, which are not analyzed in the main body of the text.
The fi rst version of this monograph was published by the Publishing House of Saint
Petersburg State University (Unipress) in 2009 under the title “Evolution of sexual reproduction in the bryozoan order Cheilostomata (Gymnolaemata)” (Ostrovsky 2009). Since that time,
new data emerged that led to a critical reassessment of some parts of the book. As a result the
text of the present English edition has been considerably rewritten and supplemented. In particular, bryozoan reproduction is compared throughout the monograph with that in other
aquatic invertebrates. These changes called for a change in the title of the book.
References
Abouheif E, Zardoya R, Meyer A (1998) Limitations of metazoan 18s RNA sequence data: implications for
reconstructing a phylogeny of the animal kingdom and inferring the reality of the Cambrian explosion. J
Mol Evol 47:394–405
Adiyodi KG, Adiyodi RG (eds) (1983) Reproductive biology of invertebrates, vol 1. Oogenesis, oviposition,
and oosorption. John Wiley and Sons, Chichester
Adiyodi KG, Adiyodi RG (eds) (1989) Reproductive biology of invertebrates, vol 4. Part A: fertilization, development, and parental care. IBH Publishing Co Pvt Ltd, New Delhi/Bombay/Calcutta/Oxford
Adiyodi KG, Adiyodi RG (eds) (1990) Reproductive biology of invertebrates, vol 4. Part B: fertilization, development, and parental care. IBH Publishing Co Pvt Ltd, New Delhi/Bombay/Calcutta/Oxford
Allman G (1856) A monograph of the fresh-water Polyzoa, including all the known species, both British and
foreign. Ray Society, London
Anderson DT (2001) Invertebrate zoology. Oxford University Press, Oxford
Anstey RL (1990) Bryozoans. In: McNamara KJ (ed) Evolutionary trends. University of Arizona Press, Tucson,
pp 232–252
Anstey RL, Pachut JF (1995) Phylogeny, diversity history and speciation in Paleozoic bryzoans. In: Erwin DH,
Anstey RL (eds) New approaches to speciation in the fossil record. Colombia University Press, New York,
pp 239–284
Introduction