Emergence of macroscopic directed motion in populations of motile colloids

@article{Bricard2013EmergenceOM,
  title={Emergence of macroscopic directed motion in populations of motile colloids},
  author={Antoine Bricard and Jean-Baptiste Caussin and Nicolas Desreumaux and Olivier Dauchot and Denis Bartolo},
  journal={Nature},
  year={2013},
  volume={503},
  pages={95-98}
}
From the formation of animal flocks to the emergence of coordinated motion in bacterial swarms, populations of motile organisms at all scales display coherent collective motion. This consistent behaviour strongly contrasts with the difference in communication abilities between the individuals. On the basis of this universal feature, it has been proposed that alignment rules at the individual level could solely account for the emergence of unidirectional motion at the group level. This… 
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