The Choanoflagellates: Evolution, Biology and Ecology. By Barry S. C. Leadbeater. Cambridge and New York: Cambridge University Press. $125.00. xiii + 315 p.; ill.; choanoflagellate species index, other species index, general index. ISBN: 978-0-521-88444-0. 2015.

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Previous articleNext article FreeMicrobiologyThe Choanoflagellates: Evolution, Biology and Ecology. By Barry S. C. Leadbeater. Cambridge and New York: Cambridge University Press. $125.00. xiii + 315 p.; ill.; choanoflagellate species index, other species index, general index. ISBN: 978-0-521-88444-0. 2015.Tom FenchelTom FenchelMarine Biological Laboratory, University of Copenhagen, Helsingør, Denmark Search for more articles by this author Marine Biological Laboratory, University of Copenhagen, Helsingør, DenmarkPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreThe choanoflagellates comprise a group of nonphotosynthetic protists that occur in fresh and seawater as well as in soils. The cells are characterized by a single flagellum surrounded by a collar: a single layer of microvilli that form a frustum of a cone or a cylinder. The flagellum draws a water current through the collar from the outside, thus retaining suspended bacteria that are subsequently phagocytized at the base of the collar. Some choanoflagellate species occur as single cells while others form cell colonies that may be attached to a solid substratum such as, for example, algal filaments or, in some species, occur as free-swimming colonies. The loricate choanoflagellates are exclusively found in seawater; they live inside a complicated lorica composed of silica spicules. In other groups, cells occur naked or they are covered by an organic theca. Choanoflagellates are important consumers of bacteria in the water column of the sea.Already in the second half of the 19th century it was noted that there is a close similarity between choanoflagellates and choanocytes (a characteristic cell type of sponges) with respect to structure and function. And so it was speculated that the ancestors of sponges and then, perhaps, metazoans in general were colonial choanoflagellates. Much more recent molecular evidence has shown that the choanoflagellates actually do represent a sister group to the metazoans and that this is to some extent supported by similarities in fine structural details of the cells. These results have again led to a revived interest in the choanoflagellates.The author of the book is associated with the University of Birmingham and he is a leading expert on choanoflagellates. His volume includes 10 chapters that treat the three major groups of choanoflagellates with respect to taxonomy, structure, functional biology, and ecology. A final chapter is devoted to the phylogeny of the opisthokonts—a major group among the eukaryotes that include the fungi, choanoflagellates, and the metazoans in addition to a couple of groups represented by unicellular parasites. This chapter provides a critical discussion of different aspects such as whether the choanoflagellate cell is really homologous with the choanocytes of sponges, as well as other evidence for the possible role of choanoflagellates as ancestors of metazoans in terms of cell structure, biochemical aspects, and connections between the cells in colony-forming species.The Choanoflagellates is an excellent and authoritative book that covers all aspects of this group of protozoans and it will remain so for quite some time. It can be warmly recommended to protozoologists and to anyone interested in the origin of metazoans and in the evolution of multicellularity. Previous articleNext article DetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 92, Number 1March 2017 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/690889 For permission to reuse, please contact [email protected]PDF download Crossref reports no articles citing this article.