Protistology 1 (3) 133 (2000)
BOOK REVIEW
L.N. Seravin and A.V. Goodkov. 1999. AGAMIC FUSIONS OF PROTISTS AND THE ORIGIN OF SEXUAL
PROCESS. (In Russian with English Contents and Summary). Published by "Biological Series", St. Petersburg-Omsk, Russia. 155 pp.,
with 5 tables.
The book includes a lot of information on the problems mentioned in its title. Actually, a number of investigations into agamic fusions
of Euhyperamoeba fallax (Lobosea, Gymnamoebia) have been made by the same team of authors. On this basis, they have also
published some review articles on this topic, but, unfortunately, only in Russian. Therefore, the Western readers obviously do not know
much about these investigations. The same can be said about the future of this edition, in view of which an English edition of the book
would be most welcome.
The publication represents a very serious attempt to summarize the vast information concerning the topic (the authors used 487 citations
of various works) and formulate a new "generalized hypothesis" of the origin of meiosis and sexual process.
The structure of the volume is as follows. The main purposes of the work and some notions are presented in the Introduction.
Chapter 1 "Agamic cell fusions (somatogamy) in protists" shows these phenomena to be rather widely distributed in nature. The authors
propose some kind of classification of agamic cell fusions in protists. In particular, they distinguish among three main types:
pseudocopulation, plasmodization and pseudoconjugation. Chapter 2 "From mitosis to meiosis" deals with the classical and abnormal
forms of mitosis and meiosis. Some aspects of multinuclearity, increase of ploidy, and the ways of somatic reduction of chromosome
number in the nucleus are considered. Chapter 3 "Polyphyletic origin of meiosis and sexual process" appears to be the principal part of
the work. The authors provide a broad critical discussion of some publications on this theme, in particular, Cavalier-Smith's article
"Cell cycles, diplokaryosis and the archezoan origin of sex" (Arch. Protistenkd. 1995. 145, 189-207). Chapter 4 "Generalized hypothesis
of the full sexual process origin" terminates the book. The hypothesis includes, in particular, the following theses: (1) The full sexual
process (as well as meiosis) originated repeatedly during protists' evolution and independently in different eukaryotic macrotaxa.
(2) The full sexual process was formed on the basis of the agamic ploidy cycle. Diploidy and polyploidy appeared in agamic haploid
protists as the result of endomitosis or karyogamy, while the reduction of ploidy was originally achieved by haploidizing mitosis or
parameiosis. (3) The primary function of the meiosis was haploidization of the nuclear apparatus. (4) There were at least four different
ways of origin of the sexual process. In most cases, some kind of agamic fusion of protists can be considered as its prerequisite.
The brief review permits only a cursory listing of the book's contents. The amount of information contained in every page of the book
sometimes makes the text a rather complicated reading. Some additional diagrams would probably help to better understand the material.
However, the appearance of this book should undoubtedly be welcomed.
Sergei I. Fokin, St. Petersburg State University, Russia.
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