Evolution of cooperation +/or selfish behavior

• System: Myxococcus xanthus

• Primary Investigator: Greg Velicer

Myxococcus xanthus

http://cmgm.stanford.edu/~kaiserla/about_myxo/about_myxococcus.html

• Adventurous motility• Social motility• Gliding motility• Development of spores

• Motility can be A = adventurous or S = social

• A motility = dependent upon gliding and slime extrusion

• S motility = dependent upon type IV pili

First experimental evo of Myxo

• 12 populations, 6 RifR, shaking flasks, CTT (rich) media.

• Inhibits social contact; mass-action

But the selfish asocial evolved lineages cheat…

Cooperation can evolve along multiple pathways

Cooperation re-evolves using a new system

• cglB = A motility gene

• dsp = fibril producing gene