Beyond society: the evolution of organismality.
The evolution of organismality is a social process. All organisms originated from groups of simpler units that now show high cooperation among the parts and are nearly free of conflicts. We suggest that this near-unanimous cooperation be taken as the defining trait of organisms. Consistency then requires that we accept some unconventional organisms, including some social insect colonies, some microbial groups and viruses, a few sexual partnerships and a number of mutualistic associations. Whether we call these organisms or not, a major task is to explain such cooperative entities, and our survey suggests that many of the traits commonly used to define organisms are not essential. These non-essential traits include physical contiguity, indivisibility, clonality or high relatedness, development from a single cell, short-term and long-term genetic cotransmission, germ-soma separation and membership in the same species.
Queller
David C
DC
Department of Ecology and Evolutionary Biology, Rice University, 6100 Main Street, Houston, TX 777005, USA. queller@rice.edu
Strassmann
Joan E
JE
D000818:Animals; D003468:Cultural Evolution; D006801:Humans; D012919:Social Behavior