There were errors in Biology Open (2017) 6, bio026997 (doi:10.1242/bio.026997).
The wrong Fig. 8 was used in the published paper. The correct and original figure are shown below and both the online full-text and PDF versions of the article have been updated.
Fig. 8 (correct image).
Fig. 8 (original image).
The authors apologise for these errors and any inconvenience they may have caused.
This correction does not affect the results in the article or the conclusions of this study.