Cooperation and the Evolution of Multicellularity

Coordinators: David Bensimon, Cassandra Extavour, Greg Huber, Rick Michod

This program will bring together theorists and experimentalists to explore the mystery of how and why single cells subsumed their fitness in favor of multicellular collectives and, further, how and why groups of cells evolved into multicellular individuals.  A variety of theoretical and experimental approaches will be represented during the program, many revolving around the central notion of cooperation.  Cooperation occurs throughout the biological world, and strikingly similar patterns of cooperative organization appear across the hierarchies of biological structures: Genes organize into genomes, cells into multicellular organisms, organisms into institutions and societies, and species into ecologies.  While deep analogies between mechanisms at one such level of organization and mechanisms at another level suggest themselves, general organizing principles have often been greeted with controversy.


There are signs that the study of cooperation and its evolution is entering a new period, as theoretical advances meet with advances in molecular biology, genomics and cell biology, allowing greater access to the deepest levels of the underlying machinery acted on by natural selection.  The new tools and technologies available to observe and manipulate genes, cells, microorganisms and collectives have resulted in new experimentally tractable systems and new data to probe classical ideas of fitness, the structure of communities, and the evolution of cooperation.  We have organized a program where we hope the interplay of theory and experiment can provide the foundation for new collaborative work in this field.


In addition to theorists spending an extensive period on site, the program will host a number of experimentalists coming for shorter periods.  Researchers in the program area are welcome at any time, but we have modulated the thematic emphasis over the 2.5-month period to provide opportunities for focus.  The program begins on January 7, 2013 with a week of introduction to common theoretical tools and frameworks.  Four intensive themes follow, spaced out over the course of the program. Themes have been chosen to cut across and tie together multiple dimensions: levels of selection (population genetics), molecular interactions (molecular biology), and theory (physics, mathematical biology). 


In close connection with the thematic program, we are organizing a conference, Cooperation and Major Evolutionary Transitions, February 4-8, 2013.


A rough outline of themes is as follows:

Week beginning


January 7

Introduction to common theoretical frameworks and tools

January 14

Physics of collectives; fitness, relatedness, levels of selection

January 28

Multicellularity: Principles and varieties

February 4

Conference: Cooperation & major evolutionary transitions

February 18

Multicellularity: Benefits, costs and cancer

March 4

Germ lines, division of labor

March 11

From biofilms to tissues

These may be changed as we find out when researchers can attend. Questions should be directed to one of the program coordinators.