Choanoflagellates have three distinctive claims to fame

they are the closest, living, unicellular relatives of animals; they are a major component of aquatic microbial foodwebs; and one group is remarkable for its siliceous basket-like coverings. This landmark book offers a unique synthesis of over forty years of choanoflagellates research.

Key areas are covered, from the phylogenetic evidence supporting the sister-group relationship between choanoflagellates and Metazoa, to choanoflagellate distribution and diversity in marine and freshwater environments.

The structure and assembly of choanoflagellate loricae is also presented together with a full discussion of a novel example of regulatory evolution, suggesting that the switch from nudiform to tectiform cell division and lorica production was achieved by a sudden reorganisation of existing structures and mechanisms.

Providing an authoritative summary of what is currently known about choanoflagellates, this title will serve as a foundation upon which future research and discussion can take place.