There was an error published in J. Exp. Biol. 211, 1657-1667.

In Fig. 9B (top panel), an incorrect graph was published. Instead of the correct data, the data from Fig. 9A was inadvertently duplicated in Fig. 9B. The correct version of Fig. 9 is published below.

The authors apologise for any inconvenience caused and would like to reassure readers that this error does not influence any of the results or conclusions of the paper.