L3 → Tm9 connection strength across connectome datasets

Every individual L3→Tm9 neuron pair in VFB (5,354 pairs, synapse threshold ≥1), binned by synapse count. Distributions are near-identical across the three well-sampled datasets — a low-count shoulder of weak/incidental contacts plus a broad main peak around 22–30 synapses (the genuine columnar retinotopic connection). Hover a point for its value.

0 50 100 150 200 250 300 350 400 0 5 10 15 20 25 30 35 40 45 Synapse count per L3→Tm9 connection Frequency (connection pairs) male-CNS — 2 synapses: 384 pairs male-CNS — 3 synapses: 164 pairs male-CNS — 4 synapses: 77 pairs male-CNS — 5 synapses: 50 pairs male-CNS — 6 synapses: 21 pairs male-CNS — 7 synapses: 24 pairs male-CNS — 8 synapses: 14 pairs male-CNS — 9 synapses: 22 pairs male-CNS — 10 synapses: 26 pairs male-CNS — 11 synapses: 23 pairs male-CNS — 12 synapses: 25 pairs male-CNS — 13 synapses: 19 pairs male-CNS — 14 synapses: 40 pairs male-CNS — 15 synapses: 32 pairs male-CNS — 16 synapses: 34 pairs male-CNS — 17 synapses: 46 pairs male-CNS — 18 synapses: 54 pairs male-CNS — 19 synapses: 52 pairs male-CNS — 20 synapses: 59 pairs male-CNS — 21 synapses: 71 pairs male-CNS — 22 synapses: 70 pairs male-CNS — 23 synapses: 85 pairs male-CNS — 24 synapses: 90 pairs male-CNS — 25 synapses: 91 pairs male-CNS — 26 synapses: 78 pairs male-CNS — 27 synapses: 84 pairs male-CNS — 28 synapses: 87 pairs male-CNS — 29 synapses: 87 pairs male-CNS — 30 synapses: 75 pairs male-CNS — 31 synapses: 78 pairs male-CNS — 32 synapses: 81 pairs male-CNS — 33 synapses: 71 pairs male-CNS — 34 synapses: 61 pairs male-CNS — 35 synapses: 44 pairs male-CNS — 36 synapses: 51 pairs male-CNS — 37 synapses: 28 pairs male-CNS — 38 synapses: 31 pairs male-CNS — 39 synapses: 21 pairs male-CNS — 40 synapses: 20 pairs male-CNS — 41 synapses: 12 pairs male-CNS — 42 synapses: 6 pairs male-CNS — 43 synapses: 9 pairs male-CNS — 44 synapses: 5 pairs male-CNS — 45 synapses: 2 pairs male-CNS — 46 synapses: 4 pairs male-CNS — 47 synapses: 3 pairs FlyWire — 2 synapses: 144 pairs FlyWire — 3 synapses: 71 pairs FlyWire — 4 synapses: 51 pairs FlyWire — 5 synapses: 26 pairs FlyWire — 6 synapses: 28 pairs FlyWire — 7 synapses: 26 pairs FlyWire — 8 synapses: 30 pairs FlyWire — 9 synapses: 37 pairs FlyWire — 10 synapses: 24 pairs FlyWire — 11 synapses: 29 pairs FlyWire — 12 synapses: 33 pairs FlyWire — 13 synapses: 27 pairs FlyWire — 14 synapses: 24 pairs FlyWire — 15 synapses: 35 pairs FlyWire — 16 synapses: 31 pairs FlyWire — 17 synapses: 40 pairs FlyWire — 18 synapses: 29 pairs FlyWire — 19 synapses: 43 pairs FlyWire — 20 synapses: 34 pairs FlyWire — 21 synapses: 55 pairs FlyWire — 22 synapses: 67 pairs FlyWire — 23 synapses: 51 pairs FlyWire — 24 synapses: 53 pairs FlyWire — 25 synapses: 57 pairs FlyWire — 26 synapses: 59 pairs FlyWire — 27 synapses: 56 pairs FlyWire — 28 synapses: 54 pairs FlyWire — 29 synapses: 56 pairs FlyWire — 30 synapses: 55 pairs FlyWire — 31 synapses: 29 pairs FlyWire — 32 synapses: 30 pairs FlyWire — 33 synapses: 44 pairs FlyWire — 34 synapses: 18 pairs FlyWire — 35 synapses: 21 pairs FlyWire — 36 synapses: 18 pairs FlyWire — 37 synapses: 15 pairs FlyWire — 38 synapses: 9 pairs FlyWire — 39 synapses: 4 pairs FlyWire — 40 synapses: 8 pairs FlyWire — 41 synapses: 1 pairs FlyWire — 42 synapses: 3 pairs FlyWire — 43 synapses: 2 pairs FlyWire — 47 synapses: 1 pairs Optic Lobe — 2 synapses: 216 pairs Optic Lobe — 3 synapses: 91 pairs Optic Lobe — 4 synapses: 48 pairs Optic Lobe — 5 synapses: 27 pairs Optic Lobe — 6 synapses: 17 pairs Optic Lobe — 7 synapses: 10 pairs Optic Lobe — 8 synapses: 10 pairs Optic Lobe — 9 synapses: 11 pairs Optic Lobe — 10 synapses: 15 pairs Optic Lobe — 11 synapses: 11 pairs Optic Lobe — 12 synapses: 9 pairs Optic Lobe — 13 synapses: 11 pairs Optic Lobe — 14 synapses: 15 pairs Optic Lobe — 15 synapses: 11 pairs Optic Lobe — 16 synapses: 14 pairs Optic Lobe — 17 synapses: 14 pairs Optic Lobe — 18 synapses: 24 pairs Optic Lobe — 19 synapses: 18 pairs Optic Lobe — 20 synapses: 24 pairs Optic Lobe — 21 synapses: 20 pairs Optic Lobe — 22 synapses: 27 pairs Optic Lobe — 23 synapses: 35 pairs Optic Lobe — 24 synapses: 37 pairs Optic Lobe — 25 synapses: 52 pairs Optic Lobe — 26 synapses: 33 pairs Optic Lobe — 27 synapses: 42 pairs Optic Lobe — 28 synapses: 43 pairs Optic Lobe — 29 synapses: 45 pairs Optic Lobe — 30 synapses: 42 pairs Optic Lobe — 31 synapses: 48 pairs Optic Lobe — 32 synapses: 53 pairs Optic Lobe — 33 synapses: 38 pairs Optic Lobe — 34 synapses: 35 pairs Optic Lobe — 35 synapses: 31 pairs Optic Lobe — 36 synapses: 32 pairs Optic Lobe — 37 synapses: 20 pairs Optic Lobe — 38 synapses: 20 pairs Optic Lobe — 39 synapses: 16 pairs Optic Lobe — 40 synapses: 16 pairs Optic Lobe — 41 synapses: 10 pairs Optic Lobe — 42 synapses: 5 pairs Optic Lobe — 43 synapses: 9 pairs Optic Lobe — 44 synapses: 4 pairs Optic Lobe — 45 synapses: 2 pairs Optic Lobe — 46 synapses: 3 pairs Optic Lobe — 47 synapses: 1 pairs
male-CNS (n=2,511) FlyWire (n=1,528) Optic Lobe (n=1,315)
DatasetPairsMinMedianMeanMax
male-CNS2,51122219.247
FlyWire1,52822118.647
Optic Lobe1,31522319.747

Hemibrain, FAFB-CATMAID, MANC and larval L1 are excluded — L3/Tm9 are optic-lobe cells those datasets don’t cover. BANC is also excluded: its current VFB load holds only 2 L3→Tm9 pairs, too few to form a distribution. Counts are raw (un-normalised), so compare the shapes of the distributions rather than absolute peak heights. Data pulled live with the VFB MCP query_connectivity tool.