title: Swarming bacteria migrate by Lévy Walk.
abstract: Individual swimming bacteria are known to bias their random trajectories in search of food and to optimize survival. The motion of bacteria within a swarm, wherein they migrate as a collective group over a solid surface, is fundamentally different as typical bacterial swarms show large-scale swirling and streaming motions involving millions to billions of cells. Here by tracking trajectories of fluorescently labelled individuals within such dense swarms, we find that the bacteria are performing super-diffusion, consistent with Lévy walks. Lévy walks are characterized by trajectories that have straight stretches for extended lengths whose variance is infinite. The evidence of super-diffusion consistent with Lévy walks in bacteria suggests that this strategy may have evolved considerably earlier than previously thought.
authors.affiliation: Department of Mathematics, Bar-Ilan University, Ramat Gan 52000, Israel.
authors.forename: Gil
authors.initials: G
authors.lastname: Ariel
authors.affiliation: Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 84990, Midreshet Ben-Gurion, Israel.
authors.forename: Amit
authors.initials: A
authors.lastname: Rabani
authors.affiliation: Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 84990, Midreshet Ben-Gurion, Israel.
authors.forename: Sivan
authors.initials: S
authors.lastname: Benisty
authors.affiliation: Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Partridge
authors.affiliation: Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: Rasika M
authors.initials: RM
authors.lastname: Harshey
authors.affiliation: Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus 84990, Midreshet Ben-Gurion, Israel.
authors.forename: Avraham
authors.initials: A
authors.lastname: Be'er
mesh_terms: D001412:Bacillus subtilis / Q000502:physiology*; D049452:Green Fluorescent Proteins; D008124:Locomotion / Q000502:physiology*; D049408:Luminescent Agents; D008164:Luminescent Proteins; D061848:Optical Imaging; D012706:Serratia marcescens / Q000502:physiology*; D000097573:Red Fluorescent Protein
chemical_list: D049452:Green Fluorescent Proteins; D049408:Luminescent Agents; D008164:Luminescent Proteins; D000097573:Red Fluorescent Protein