Major Evolutionary Transitions in Individuality

* Article: Major evolutionary transitions in individuality. Stuart A. West, Roberta M. Fisher, Andy Gardner, and E. Toby Kiers. PNAS August 18, 2015 112 (33) 10112-10119; doi

URL = https://www.pnas.org/content/112/33/10112

Contextual Quote

"The major transitions approach provides a conceptual framework that facilitates comparison across pivotal moments in the history of life. It suggests that the same problem arises at each transition: How are the potentially selfish interests of individuals overcome to form mutually dependent cooperative groups? We can then ask whether there are any similarities across transitions in the answers to this problem."

- Stuart West et al. [1]

Abstract

"The evolution of life on earth has been driven by a small number of major evolutionary transitions. These transitions have been characterized by individuals that could previously replicate independently, cooperating to form a new, more complex life form. For example, archaea and eubacteria formed eukaryotic cells, and cells formed multicellular organisms. However, not all cooperative groups are en route to major transitions. How can we explain why major evolutionary transitions have or haven’t taken place on different branches of the tree of life? We break down major transitions into two steps: the formation of a cooperative group and the transformation of that group into an integrated entity. We show how these steps require cooperation, division of labor, communication, mutual dependence, and negligible within-group conflict."