During the evolution ofmulticellular organisms, the unit of selection and adaptation, the individual, changes fromthe single cell to themulticellular group. To become individuals, groups must evolve a group life cycle in which groups reproduce other groups. Investigations into the origin of group reproduction have faced a chicken-and-egg problem: Traits related to reproduction at the group level often appear both to be a result of and a prerequisite for natural selection at the group level. With a focus on volvocine algae, we model the basic elements of the cell cycle and show how group reproduction can emerge through the coevolution of a life-history trait with a trait underpinning cell cycle change. Our model explains howevents in the cell cycle become reordered to create a group life cycle through continuous change in the cell cycle trait, but only if the cell cycle trait can coevolve with the life-history trait. Explaining the origin of group reproduction helps us understand one of life's most familiar, yet fundamental, aspects-its hierarchical structure.
- Cell cycle
- Group reproduction
- Volvocine algae
ASJC Scopus subject areas
- Agricultural and Biological Sciences (miscellaneous)
- Agricultural and Biological Sciences(all)