We added the following paragraph to the discussion: “Many of the model parameters, such as trichome length, diameter, gliding speed, reversal frequency, etc. are easily measured and are well known. However, the bending modulus is more difficult to measure directly. We attempted to use the bending modulus implied from the relation α= kBT ε and Boal and Ng’s (2010, p. 4625) measurements of the trichome persistence length, but the resulting value seemed too low compared to measurements of other bacteria and in practice the virtual trichomes appeared flaccid during simulations. It is possible that the flexure seen in Boal and Ng’s trichomes was due more to the motility of the trichomes than random thermal fluctuations, in which case the above relation would no longer be valid, and a more complex model would be required to associate the observed geometry of the trichomes to their bending modulus. For example, Wolgemuth (2005) used an elastic model to estimate the bending modulus of M. xanthus by fitting the model to the flailing motions of a Myxobacterium stuck at one end.”
In Section 4, the discussion section of the paper, the topic of the bending modulus is returned to for a paragraph. This paragraph needs to explicitly address why the measurements of Boal and Ng were not used, i.e., why Boal and Ng misinterpreted their data. In particular the authors should suggest how the measurements are significant measurements to not use. In particular this paragraph needs to R8 suggest how the measurement should be done to properly test their suggested values for the bending modulus, and so resolve the disagreement with Boal and Ng.