Synapse locations of the neurons in cluster 2 (chi = 0). Neurons on the y-axis are sorted according to cluster membership at increasing values of chi; clusters are indicated by colors in the left columns labeled with values of~chi. Repeated colors within one column indicate the same cluster. Most clusters are nested hierarchically, so there are few repeated colors within each column. In the remaining columns, the grayscale intensity shows the fraction of that neuron’s synapses in previously anatomically identified regions listed on the x-axis. For example, the dark pink cluster at chi = 0.1 (near the bottom of the figure) resides primarily in layer 2, with projections to the Noduli (NO) and protocerebral bridge (PB).