TY - JOUR
T1 - Spatial population expansion promotes the evolution of cooperation in an experimental prisoner's dilemma
AU - Van Dyken, J. David
AU - Müller, Melanie J.I.
AU - MacK, Keenan M.L.
AU - Desai, Michael M.
N1 - Funding Information:
We thank John Koschwanez for strains and Michael Whitlock, Benjamin Good, Michael McDonald, Lauren Nicolaisen, Katya Kosheleva, John Koschwanez, and members of the Desai lab for many useful discussions. J.D.V.D. acknowledges support from a National Science Foundation (NSF) postdoctoral fellowship. M.J.I.M. was supported by a research fellowship from the Deutsche Forschungsgemeinschaft. K.M.L.M. acknowledges support from the National Institute for Mathematical and Biological Synthesis, an Institute sponsored by the NSF; the US Department of Homeland Security; and the US Department of Agriculture through NSF award #EF-0832858, with additional support from the University of Tennessee, Knoxville. M.M.D. acknowledges support from the James S. McDonnell Foundation and the Alfred P. Sloan Foundation.
PY - 2013/5/20
Y1 - 2013/5/20
N2 - Cooperation is ubiquitous in nature, but explaining its existence remains a central interdisciplinary challenge [1-3]. Cooperation is most difficult to explain in the Prisoner's Dilemma game, where cooperators always lose in direct competition with defectors despite increasing mean fitness [1, 4, 5]. Here we demonstrate how spatial population expansion, a widespread natural phenomenon [6-11], promotes the evolution of cooperation. We engineer an experimental Prisoner's Dilemma game in the budding yeast Saccharomyces cerevisiae to show that, despite losing to defectors in nonexpanding conditions, cooperators increase in frequency in spatially expanding populations. Fluorescently labeled colonies show genetic demixing [8] of cooperators and defectors, followed by increase in cooperator frequency as cooperator sectors overtake neighboring defector sectors. Together with lattice-based spatial simulations, our results suggest that spatial population expansion drives the evolution of cooperation by (1) increasing positive genetic assortment at population frontiers and (2) selecting for phenotypes maximizing local deme productivity. Spatial expansion thus creates a selective force whereby cooperator-enriched demes overtake neighboring defector-enriched demes in a "survival of the fastest." We conclude that colony growth alone can promote cooperation and prevent defection in microbes. Our results extend to other species with spatially restricted dispersal undergoing range expansion, including pathogens, invasive species, and humans.
AB - Cooperation is ubiquitous in nature, but explaining its existence remains a central interdisciplinary challenge [1-3]. Cooperation is most difficult to explain in the Prisoner's Dilemma game, where cooperators always lose in direct competition with defectors despite increasing mean fitness [1, 4, 5]. Here we demonstrate how spatial population expansion, a widespread natural phenomenon [6-11], promotes the evolution of cooperation. We engineer an experimental Prisoner's Dilemma game in the budding yeast Saccharomyces cerevisiae to show that, despite losing to defectors in nonexpanding conditions, cooperators increase in frequency in spatially expanding populations. Fluorescently labeled colonies show genetic demixing [8] of cooperators and defectors, followed by increase in cooperator frequency as cooperator sectors overtake neighboring defector sectors. Together with lattice-based spatial simulations, our results suggest that spatial population expansion drives the evolution of cooperation by (1) increasing positive genetic assortment at population frontiers and (2) selecting for phenotypes maximizing local deme productivity. Spatial expansion thus creates a selective force whereby cooperator-enriched demes overtake neighboring defector-enriched demes in a "survival of the fastest." We conclude that colony growth alone can promote cooperation and prevent defection in microbes. Our results extend to other species with spatially restricted dispersal undergoing range expansion, including pathogens, invasive species, and humans.
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U2 - 10.1016/j.cub.2013.04.026
DO - 10.1016/j.cub.2013.04.026
M3 - Article
C2 - 23664975
AN - SCOPUS:84878020408
VL - 23
SP - 919
EP - 923
JO - Current Biology
JF - Current Biology
SN - 0960-9822
IS - 10
ER -