Throughout their pursuit of a whole-brain wiring diagram (connectome) of an adult fly, the creators of Flywire made their data available as an open resource, which enabled a community of mostly Drosophila melanogaster researchers — the FlyWire consortium — to both proofread neurons and annotate its features (necessary for integration with functional work). Now, Dorkenwald et al. provide an overview of the resulting brain resource and the how it can be used it to explore global information flow.

To acquire a connectome that contains 100,000–140,000 neurons and over 50 million synaptic connections, images were first acquired by serial section transmission electron microscopy of an entire adult female D. melanogaster brain. Following automatic alignment and segmentation, all neurons underwent manual proofreading by an online community that initially comprised specialists focused on their neurons of interest and then later expanded to broader teams with contributions from professional proofreaders and citizen scientists worldwide. In total, the highly accurate and complete brain reconstruction took an estimated 33 person-years of manual proofreading, yet less than 5 years to complete — a testament to the power of collaborative open science — and remains open for manual proofreading and annotation.