Nature Communications 7: Article number: 12976 doi: (2016); Published: 30 September 2016; Updated: 23 November 2016

In Fig. 3 of this Article, an image attribution was inadvertently omitted. The drawing of a Drosophila larva in Fig. 3a is reproduced from the website http://www.prokop.co.uk/Research/Drosi-Info/nerve-cords.html with the kind permission of Dr Andreas Prokop.