Motile curved bacteria are Pareto-optimal

Research output: Contribution to journalArticle


  • Rudi Schuech
  • Tatjana Hoehfurtner
  • David Smith
  • Stuart Humphries

Colleges, School and Institutes

External organisations

  • University of Lincoln


Curved rods are a ubiquitous bacterial phenotype, but the fundamental question of why they are shaped this way remains unanswered. Through in silico experiments, we assessed freely swimming straight- and curved-rod bacteria of a wide diversity of equal-volume shapes parameterized by elongation and curvature, and predicted their performances in tasks likely to strongly influence overall fitness. Performance trade-offs between these tasks lead to a variety of shapes that are Pareto-optimal, including coccoids, all straight rods, and a range of curvatures. Comparison with an extensive morphological survey of motile curved-rod bacteria indicates that the vast majority of species fall within the Pareto-optimal region of morphospace. This result is consistent with evolutionary trade-offs between just three tasks: efficient swimming, chemotaxis, and low cell construction cost. We thus reveal the underlying selective pressures driving morphological diversity in a widespread component of microbial ecosystems.


Original languageEnglish
Pages (from-to)14440–14447
Number of pages8
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number29
Early online date2 Jul 2019
Publication statusPublished - 16 Jul 2019


  • motility, shape, morphology, swimming, evolution