Research report · 29 October 2026 · twenty-sixth check
Twenty-sixth check: four plain answers with their sources, and two claims checked
We answered four questions readers ask, each clause with a dated source; graded two new projects with wiring controls and recorded one write-up; re-read flybench after new commits; and checked two new claims: a Nature paper on a walking circuit and videos saying a fly brain was "uploaded".
Short answer
No dead fly came back to life in a computer. The wiring map comes from one preserved fly brain, cut into thin slices and imaged; models run it as a simplified simulation, and we found no recordings of that fly's activity among the model's parameters. The full answer, and three more (open source, specs, "hells"), are on Is it real?
Two new projects help against scrambled wiring, each with a limit that weighs on it: in Buzz the gains were tuned on the intact wiring and one shuffle was run; in Synaptera BANC the gap is small and an unconstrained network does better. A third, Oruk Labs, reports no difference, but publishes no code. Fly wiring now beats scrambled wiring in 35 of 87 studies.
Flybench keeps A: the author corrected one task's input rate (80 to 65 Hz); in the cited result files the signed build now reads graded 0.74, specificity +0.33, and other cited scores moved by less than 0.01; the control code is unchanged, and a preprint is now linked.
Four plain answers, each clause with a source
Sources read on 29 Oct 2026 unless dated otherwise · sentences as published on Is it real?
Is the fruit fly brain open source?
The main wiring maps are free to download, under different licences: FlyWire (FAFB): CC BY-NC 4.0 on FlyWire's own site (flywire.ai/guidelines), while its Zenodo record lists CC BY 4.0 (zenodo.org/records/10676866); both checked 29 Oct 2026, and we follow the stricter non-commercial reading. MaleCNS: CC-BY (male-cns.janelia.org, checked 29 Oct 2026). Hemibrain: CC-BY (janelia.org hemibrain page, checked 29 Oct 2026). BANC: CC BY 4.0 (BANC project README, checked 29 Oct 2026). Code licences vary by project, and each catalogue entry lists its own. Free to download does not always mean free for any use: FlyWire's own site gives a non-commercial licence, so we treat its data as not allowing commercial use without permission.
The FlyWire conflict is still there at source: its own site gives CC BY-NC 4.0 and its Zenodo record CC BY 4.0. We name both and follow the stricter reading. Download sizes are in How it works.
What do I need to run it?
Our beginner project ran on a computer with 2 CPUs. The whole test container, which was also running other work, used at most about 2.1 GB of memory; the folder with the install, the code and the data took about 660 MB of disk, and the smallest example ran in about 68 seconds (measured 19 Oct 2026). We tested one machine. Larger projects need more; for example, FlyGym states that its new version runs at about 2x real time on a CPU and about 50x real time on a GPU (FlyGym README, checked 29 Oct 2026).
Narrowed before publication: the memory figure is the peak of the whole shared test container, not of the project alone, and "no graphics card" was removed because our 19 Oct files do not record it.
Did a dead fly come back to life in a computer?
No. The wiring map comes from the brain of one adult fruit fly, which was preserved, cut into very thin slices and imaged with an electron microscope (Zheng et al. 2018, Cell). Researchers traced its neurons and the connections between them (Dorkenwald et al. 2024, Nature). Models such as the Shiu et al. 2024 brain model turn the map into a simplified simulation: every neuron is a simple spiking unit (leaky integrate-and-fire), with connection strengths taken from the map's synapse counts and predicted neurotransmitters (Shiu et al. 2024, Nature). Its parameters come from the wiring map, predicted neurotransmitters and earlier modelling studies; we found no recordings of that fly's activity among them (Shiu et al. 2024, Methods). Whether the map keeps any trace of that fly's own experience is an open question; we found no study that tests it (checked 29 Oct 2026).
Changed before publication: the paper does not say that the connections stay fixed while the model runs, so we do not say it. "No recordings" is our reading of the parameter list together with the fixed tissue; "no study" rests on one web search.
Could this become a 'hell' for future simulated brains?
Some writers argue that as people get better at reading and steering simulated brains, and as these models are shared openly, some people will use them to try to cause suffering ("There Will Be Hells", LessWrong, 20 Oct 2026). Today's fly models leave out gap junctions, neurons that do not spike, internal state and long-range neuropeptides, and the brain model starts every neuron at zero background activity (Shiu et al. 2024); the essay itself calls the fly model oversimplified. We found no study that measured consciousness or suffering in these models, and whether flies feel pain is open. Whether any of these models, or a future one, can feel anything is not known.
Dropped before publication: "running many copies at a large scale" is not in the essay (a commenter writes "millions"). The essay had about 290 karma and about 70 comments on 29 Oct 2026 (approximate).
3 new entries and 3 new ledger rows
The authors' numbers; Buzz trial counts recounted by us from its committed files; nothing re-run by us
| Project | Effect | Real wiring | Scrambled wiring | Limits |
|---|---|---|---|---|
| Buzz (archpc) A | Helps | Escape neuron fired in 30 of 36 looming trials | 0 of 36 with edge weights shuffled (same graph) | Gains hand-tuned on the intact wiring; one shuffle seed in this phase; in a later phase one of three shuffles kept a weak one-sided response. Fairness: unfair; quality: weak. |
| Synaptera BANC (omeruk) A | Helps | Test R2 0.9773 (10 seeds, pre-registered, sealed test split) | 0.9504 with degree-preserving shuffled wiring (difference 0.0268, 95% interval 0.0242 to 0.0291) | Small difference; an unconstrained network reached 0.9984; at the held-out 90 deg/s the shuffled wiring scored higher (0.9912 against 0.9838); the shuffled arm was still improving at the end of its training budget. A separate project from the Synaptera flight test (grade B). |
| Oruk Labs write-up U | No difference | 16.84% mAP on held-out voices (authors' report) | 16.88% with scrambled wiring (paired difference −0.04 points, 95% interval −0.16 to +0.07) | Write-up only, no code; the readout also receives pooled audio features directly; we did not re-run it. |
In the first screening of new code, 56 repositories were screened: 2 graded, 39 excluded (36 with no wiring comparison or no result files, 3 after reading their matches) and 15 carried to the next check unread. Six project names from our reader-question research were not screened, because no repository address was available.
flybench after new commits: grade A kept
14 commits since the grade. The control code (flybench/controls.py, flybench/bench.py) is unchanged. The author corrected one task's sugar input rate from 80 to 65 Hz and predicted that graded scores would move by less than 0.01. A preprint is now linked (doi:10.5281/zenodo.23678526).
| File | Graded score | Specificity |
|---|---|---|
results/flywire783_gain0.45.json | 0.642 (was 0.640) | 0.214 (unchanged) |
results/flywire783_shiu_gain0.7.json | 0.763 (was 0.764) | 0.331 (unchanged) |
results/flywire783_ntfix_gain0.7.json | 0.744 (was 0.749) | 0.335 (was 0.341) |
Two claims checked
29 Oct: we scanned news, videos and new code from 24 to 29 Oct; two claims were checked: a peer-reviewed walking-circuit simulation paper in Nature, and new videos saying a fly brain was 'uploaded'.
- Walking circuit (Nature, 28 Oct 2026). Pugliese and colleagues (Nature, 28 Oct 2026) report that simulations of four fly nerve-cord wiring maps found a three-neuron circuit, one inhibitory and two excitatory cells, that produced leg rhythms in the model, and that a descending pathway the simulations pointed to drove rhythmic leg movements when they activated it with light in behaving flies. The simulation code (MIT licence) and simulation data are public. We did not re-run it, and our tools could not open the journal page; we read the preprint abstract and the code repository (checked 29 Oct 2026). Not catalogued or graded yet: a wiring-shuffle option exists in the code, and we have not read its result. Dated line on Is it real?
- "Uploaded" videos. Two new videos use the word upload for a fly brain: "The First Brain Was Just Uploaded To A Computer" (AI Uncovered, 27 Oct 2026; about 26,000 views on 29 Oct) and a Japanese video whose title says a fly's brain was copied whole and run (25 Oct 2026; about 50,000 views on 29 Oct), whose description names Eon Systems' fly demo. Primary sources show a wiring map traced from one preserved fly brain and run as a simplified model, with parameters from the map, predicted neurotransmitters and earlier studies; Eon's body code is not public, so we grade its demo U. We did not watch the videos; see our answer "Did a dead fly come back to life in a computer?" (checked 29 Oct 2026). Verdict row.
- New gallery card: “They Lied to you about the Virtual Fly Brain” (10 Physics). A video explainer by 10 Physics (16 Oct 2026; about 411,000 views on 29 Oct 2026) that argues many people online have been overstating what the fruit fly connectome actually is. Commentary; not watched by us.
- Odyssey-3 claim: No method, code or write-up was published as of 29 Oct 2026; no public fly mode found on the preview page (29 Oct).
Tracking and leads
- 29 Oct 2026: we looked up the latest commit of 159 tracked repositories: 128 unchanged, 13 with new commits, 1 already gone (flydoom). We re-read one of the 13, flybench, against its grade; the other 12 were not inspected and keep their grades until a later check. 56 of 56 videos available.
- Two main links did not answer on 29 Oct (ascend's demo page and FlyGym's browser viewer); both are shown as not confirmed by our link check (29 Oct), seen once. We do not call them broken; a later check will tell.
- View counts: 17 of the 56 earlier videos were refreshed from YouTube search pages on 29 Oct 2026 (approximate snapshots); the other 39 keep their earlier dated values.
- The 21 pinned Python packages of the beginner guide still have files for CPython 3.11, none withdrawn (PyPI, 29 Oct 2026); no early re-test is needed.
- Video searches answered on all queries (English, French, Spanish and Russian terms). Reddit could not be read on 29 Oct (unavailable, not zero).
What we could not resolve
- FlyWire's licence: its own site and its Zenodo record still disagree.
- The specs answer rests on one machine on 19 Oct 2026; the beginner re-test planned for early November could log the project's own memory and whether a graphics card is present.
- "No recordings of that fly's activity" is inferred; "no study" rests on one web search.
- Buzz's comparison is unfair by our rules; Synaptera BANC's advantage is small and may partly reflect the training budget.
- 12 repositories with new commits were not inspected; 15 screened names are carried unread; six suggested names were not screened.
- The Nature paper was read through its preprint abstract and code repository; its shuffle result is unread.
- YouTube view counts are approximate and dated.