The diversity of mitosis: the value of evolutionary experiments
The diversity of genome distribution systems in protists, algae, fungi, and insects is reviewed. Ultrastructural and experimental details are cited that illustrate this diversity. It is argued that an orthodox mode of daughter genome distribution does not exist; as long as the necessary precision was maintained, different components of the primordial mitotic system were modified to perform the same functions. This premise is applied to homologous genome distribution systems, and examples of meiotic diversity are cited. It is suggested that these "evolutionary experiments" provide unique opportunities for dissection of functions common to all genome distribution systems.