Volvox

by Kirk, David L

"The central thesis of this book is that Volvox and its unicellular and colonial relatives provide a wholly unrivaled opportunity to explore the proximate and ultimate causes underlying the evolution, from unicellular ancestors, of multicellular organisms with fully differentiated cell types." "A major portion of the book is devoted to reviewing what is known about the genetic, cellular, and molecular bases of development in the most extensively studied species of Volvox: V. Carteri, which exhibits a complete division of labor between mortal somatic cells and immortal germ cells. However, this topic is put in context by first considering the ecological conditions and cytological preconditions that appear to have fostered the evolution of organisms of progressively increasing sizes and with progressively increasing tendencies to produce terminally differentiated somatic cells. The book concludes by addressing the question whether the germ-soma dichotomy evolved by similar or different g