Evolution of an obligate social cheater to a superior cooperator

  title={Evolution of an obligate social cheater to a superior cooperator},
  author={Francesca Fiegna and Yuen-Tsu Nicco Yu and Supriya V. Kadam and Gregory J. Velicer},
Obligate relationships have evolved many times and can be parasitic or mutualistic. Obligate organisms rely on others to survive and thus coevolve with their host or partner. An important but little explored question is whether obligate status is an evolutionarily terminal condition or whether obligate lineages can evolve back to an autonomous lifestyle. The bacterium Myxococcus xanthus survives starvation by the social development of spore-bearing fruiting bodies. Some M. xanthus genotypes… 
Experimental evolution of selfish policing in social bacteria
The rapid evolution of cheater suppression documented here suggests that coevolving social strategies within natural populations of prokaryotes are more diverse and complex than previously appreciated.
Sociobiology: The Phoenix effect
A single spontaneous mutation in a cheater can restore proficient cooperative development and confer fitness superiority over both ancestral genotypes, including immunity from exploitation by the ancestral cheater.
High relatedness maintains multicellular cooperation in a social amoeba by controlling cheater mutants
The findings show how altruism is preserved from the disruptive effects of such mutant cheaters and how exceptionally high relatedness among cells is important in promoting the cooperation that underlies multicellular development.
Indirect evolution of social fitness inequalities and facultative social exploitation
It is demonstrated that interaction-specific fitness inequalities and facultative social exploitation during development readily evolved indirectly among descendant lineages, and that fitness inequalities caused by social interaction during cooperative processes may often evolve non-adaptively in natural populations.
Social selection within aggregative multicellular development drives morphological evolution.
It is found that even just a few genetic differences affecting developmental and social features can greatly impact morphological evolution of multicellular bodies and experimentally demonstrate that microbial warfare can promote cooperation.
Altruism and Phenoptosis as Programs Supported by Evolution
It is said that the development of altruism in the course of evolution of sociality leads in its extreme manifestation to phenoptosis, and development of mathematical models for the emergence of altruist and programmed death contributes to the understanding of mechanisms underlying these paradoxical counterproductive (harmful) programs.
Allopatric divergence limits cheating range and alters genetic requirements for a cooperative trait
The findings suggest that general divergence of social populations under a broad range of environmental conditions can restrict both the set of mutations that might generate social defectors in the first place and the host range of such defectors once they arise.
Sociobiology of the myxobacteria.
Basic social evolution concepts as they pertain to microbes are reviewed, potential benefits of myxobacterial social traits are discussed, recent empirical studies of social evolution in M. xanthus are highlighted, and their implications for how myxOBacterial cooperation and conflict evolve in the wild are considered.
Allopatric divergence of cooperators limits cheating range and effects of a defector mutation
It is shown that a defector disrupted at the signaling gene csgA has a narrow cheating range among diverse natural cooperators owing to antagonisms not specifically targeted at defectors, and suggests that natural populations feature geographic mosaics of cooperators diversified in susceptibility to cheating by any given defector and in the social phenotypes generated by anygiven mutation in a cooperation gene.
Social selection within aggregative multicellular development drives morphological evolution
It is found that even few genetic differences affecting developmental and social features can greatly impact the morphological evolution of multicellular bodies and experimentally demonstrate that microbial warfare can promote cooperation.


Exploitative and Hierarchical Antagonism in a Cooperative Bacterium
This work characterized the nature of social interactions among nine developmentally proficient strains of M. xanthus and found several cases of facultative social exploitation among these natural isolates, suggesting that such exploitation may occur frequently in nature in many prokaryotes with cooperative traits.
Developmental cheating in the social bacterium Myxococcus xanthus
It is shown that social cheating exists even among prokaryotes, with clones from several evolved lines and two defined mutants exhibited cheating during development, being over-represented among resulting spores relative to their initial frequency in the mixture.
Rescue of Social Motility Lost during Evolution of Myxococcus xanthus in an Asocial Environment
Replicate populations of the social bacterium Myxococcus xanthus underwent extensive evolutionary adaptation to an asocial selective environment (liquid batch culture) and restoration of S motility in the evolved lines by genetic complementation with wild-type pil genes positively affected their fruiting body development and sporulation while negatively affecting their competitive fitness in the asocial regime.
Comprehensive mutation identification in an evolved bacterial cooperator and its cheating ancestor.
In insight into the genetic basis of two large adaptive transitions in a social bacterium, a single mutation responsible for the restoration of development in strain PX was identified, whereas 14 mutations occurred during the prior phase of experimental evolution.
Evolution of novel cooperative swarming in the bacterium Myxococcus xanthus
The evolution of novel cooperative behaviour in experimental lineages of the bacterium Myxococcus xanthus is reported, showing that fundamental transitions to primitive cooperation can readily occur in bacteria.
Social strife in the microbial world.
Altruism and social cheating in the social amoeba Dictyostelium discoideum
Microsatellite markers are used to show that different clones collected from a field population readily mix to form chimaeras, and half of the chimaeric mixtures show a clear cheater and victim.
Evolution of cooperation and conflict in experimental bacterial populations
An evolutionary transition that occurs in experimental populations of Pseudomonas fluorescens propagated in a spatially heterogeneous environment is described to show that transitions to higher orders of complexity are readily achievable, provide insights into the selective conditions, and facilitate experimental analysis of the evolution of individuality.
Loss of social behaviors by myxococcus xanthus during evolution in an unstructured habitat.
Improved performance in the liquid selective regime among evolved lines was usually associated with significant reductions in all of the major social behaviors of M. xanthus, which is apparently detrimental to fitness under asocial growth conditions.
Experimental evolution of conflict mediation between genomes.
  • Joel L. Sachs, J. Bull
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2005
This work investigated the evolution of two bacteriophages experimentally forced to obey a life cycle with elements of cooperation and conflict, whose outcome could have ranged from extinction of the population (due to selection of selfish elements) to extreme cooperation.