# Scale art sources and credits

## Active collection — September 5, 2026

At the user's request, all 84 original transparent pictures have been restored from the collection used before the notebook redesign. The exact original files are reused: 82 OpenAI-generated illustrations/reconstructions and two authentic photographic cutouts (honey bee and ladybird). No new images were generated for this restoration.

The active per-image ledger is [restored-credits.json](restored-credits.json), mirrored from `app/zoom-to-zero/image-credits.json`. Generated pictures are explicitly identified as AI-generated artwork, not attributed to unrelated photographers. The two photographs retain their original credits and licenses below. The inactive internet-image collection and its [web-credits.json](web-credits.json) ledger remain available for attribution and recovery.

The generated pictures are illustrative models, not photographs or microscope captures. Dinosaur reconstructions, biological details and colours are interpretive; molecular, atomic, quantum and Planck-scale images are conceptual. Scale values describe the named subject, not a literal measurement of a rendered image. The original production direction requested a complete isolated specimen on transparent RGBA, scientifically recognizable anatomy, neutral lighting, and no scenery, labels, glow or cropping.

The game uses its earlier dark interface with system fonts. The retained [VT323 font](https://github.com/google/fonts/tree/main/ofl/vt323), copyright 2011 The VT323 Project Authors, is under SIL OFL 1.1; its license remains at `/fonts/zoom/OFL.txt`.

## Retained source assets

The material below documents retained non-AI source files. Only the honey-bee and ladybird photo cutouts are active in the restored collection; the other retained files are not active fallbacks. Original generated assets are restored under `generated/`, `reconstructions/`, and the six `specimens/*-ai.webp` paths.

## Music

`/audio/mesmerizing-galaxy-loop.mp3` is [“Mesmerizing Galaxy” by Kevin MacLeod](https://incompetech.com/music/royalty-free/index.html?isrc=USUAN2300011), a seamless game loop licensed under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). No musical changes were made; playback volume and looping are controlled in the game.

## Authentic photo cutouts

The source photographs below were downloaded at publication resolution, had their scenery removed locally, were cropped to the animal’s visible bounds, and were exported as transparent WebP files. The animal pixels were not redrawn. The tight crop lets the game’s numeric metre value control the comparison rather than arbitrary empty space in the source photo.

| Local file                        | Source and creator                                                                                                                                                              | License and modifications                                                                                                                                          |
| --------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `specimens/blue-whale-photo.webp` | [Blue Whale 001 body bw](https://commons.wikimedia.org/wiki/File:Blue_Whale_001_body_bw.jpg), NOAA Fisheries / Protected Resources Division, Southwest Fisheries Science Center | Public domain U.S. Government work; background removed, cropped, resized, and converted to WebP                                                                    |
| `specimens/giraffe-photo.webp`    | [Giraffe (_Giraffa camelopardalis_)](<https://commons.wikimedia.org/wiki/File:Giraffe_(Giraffa_camelopardalis)_(6045315904).jpg>), Bernard DUPONT                               | [CC BY-SA 2.0](https://creativecommons.org/licenses/by-sa/2.0/); background removed, cropped, resized, and converted to WebP; this derivative remains CC BY-SA 2.0 |
| `photos/saltwater-crocodile.webp` | [Saltwater crocodile](https://commons.wikimedia.org/wiki/File:Saltwater_Crocodile_on_a_river_bank._in_Australia.jpg), Paul Thomsen / Djambalawa                                 | Public domain; background removed, cropped, resized, and converted to WebP                                                                                         |
| `photos/human.webp`               | [Bodi Tribe, Omo Valley](<https://commons.wikimedia.org/wiki/File:Bodi_Tribe,_Omo_Valley_(crop_full_body_narrow).jpg>), Rod Waddington                                          | [CC BY-SA 2.0](https://creativecommons.org/licenses/by-sa/2.0/); background removed, cropped, resized, and converted to WebP; this derivative remains CC BY-SA 2.0 |
| `photos/green-sea-turtle.webp`    | [Green sea turtle](<https://commons.wikimedia.org/wiki/File:Green_sea_turtle_(Chelonia_mydas)_Moorea.jpg>), Charles J. Sharp                                                    | [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/); background removed, cropped, resized, and converted to WebP; this derivative remains CC BY-SA 4.0 |
| `photos/common-raven.webp`        | [Common raven](https://commons.wikimedia.org/wiki/File:Corvus_corax_clarionensis,_Point_Reyes_National_Seashore.jpg), Frank Schulenburg                                         | [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/); background removed, cropped, resized, and converted to WebP; this derivative remains CC BY-SA 4.0 |
| `photos/american-bullfrog.webp`   | [American bullfrog](<https://commons.wikimedia.org/wiki/File:American_bullfrog_(51239614029).jpg>), Sam Stukel / USFWS                                                          | Public domain; background removed, cropped, resized, and converted to WebP                                                                                         |
| `photos/monarch.webp`             | [Monarch butterfly](<https://commons.wikimedia.org/wiki/File:Monarch_Butterfly_(15247873605).jpg>), Courtney Celley / USFWS                                                     | Public domain; background removed, cropped, resized, and converted to WebP                                                                                         |
| `photos/praying-mantis.webp`      | [European praying mantis](<https://commons.wikimedia.org/wiki/File:European_praying_mantis_(Mantis_religiosa)_green_female_Dobruja.jpg>), Charles J. Sharp                      | [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/); background removed, cropped, resized, and converted to WebP; this derivative remains CC BY-SA 4.0 |
| `photos/dragonfly.webp`           | [Red grasshawk](<https://commons.wikimedia.org/wiki/File:Red_grasshawk_(Neurothemis_fluctuans)_male_Phuket_2.jpg>), Charles J. Sharp                                            | [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/); background removed, cropped, resized, and converted to WebP; this derivative remains CC BY-SA 4.0 |
| `photos/honey-bee.webp`           | [Apis mellifera specimen](<https://commons.wikimedia.org/wiki/File:Apis_mellifera,_f_(53389589270).jpg>), USGS Bee Inventory and Monitoring Lab                                 | Public domain; background removed, cropped, resized, and converted to WebP                                                                                         |
| `photos/ladybird-beetle.webp`     | [Coccinella septempunctata](<https://commons.wikimedia.org/wiki/File:Coccinella_septempunctata_Linn%C3%A9,_1758_(30156309794).png>), Udo Schmidt                                | [CC BY-SA 2.0](https://creativecommons.org/licenses/by-sa/2.0/); background removed, cropped, resized, and converted to WebP; this derivative remains CC BY-SA 2.0 |
| `photos/ant.webp`                 | [Red ant](https://commons.wikimedia.org/wiki/File:Red_Ant_-_March_2025.jpg), Samantha Henneke                                                                                   | [CC BY 2.0](https://creativecommons.org/licenses/by/2.0/); background removed, cropped, resized, and converted to WebP                                             |

## Transparent stage replacements

These files replaced opaque microscope photos and boxed molecule renders. Every replacement has a transparent canvas. The three PhyloPic silhouettes and the caffeine formula were recolored to match the game's stage palette; their geometry is unchanged.

| Local file                   | Source and creator                                                                                                                                                                                              | License and notes                                                                                                                                                       |
| ---------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `tardigrade-transparent.svg` | [_Hypsibius dujardini_](https://www.phylopic.org/images/c314c714-54e3-4f66-8079-e6248115b53e/hypsibius-dujardini), Arcadia Science                                                                              | [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/); recolored yellow                                                                                         |
| `dust-mite-transparent.svg`  | [_Acarus siro_](https://www.phylopic.org/images/3799d18b-da9e-4ce8-b3c4-590b54eb432c/acarus-siro), Amy Beauvois                                                                                                 | [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/); recolored orange and used as a related-mite visual proxy, not as a taxonomic plate of _Dermatophagoides_ |
| `amoeba-transparent.svg`     | [Microorganism: amoeba](https://commons.wikimedia.org/wiki/File:202002_Microorganism_amoeba.svg), DBCLS                                                                                                         | [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)                                                                                                               |
| `pollen-transparent.svg`     | [Pollen 4](https://openclipart.org/detail/252936/pollen-4), Firkin, traced from Carl Julius Fritzsche's 1837 _Ueber den Pollen_                                                                                 | Public domain / [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/)                                                                                           |
| `hair-transparent.svg`       | [Human hair SEM](https://commons.wikimedia.org/wiki/File:Human_hair_SEM.svg), Guillaume Paumier                                                                                                                 | [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0/)                                                                                                         |
| `giardia-transparent.svg`    | [_Giardia intestinalis_ cyst](https://github.com/duerrsimon/bioicons/blob/d29e766ea7580b8063c4f47b29e872db40a4d979/static/icons/cc-by-3.0/Parasites/Servier/giardia_intestinalis-cyst.svg), Servier Medical Art | [CC BY 3.0](https://creativecommons.org/licenses/by/3.0/)                                                                                                               |
| `mycoplasma-transparent.svg` | [_Mycoplasma genitalium_](https://www.phylopic.org/images/3a181cb2-0cd6-42ca-b876-e1225af83e65/mycoplasma-genitalium), Guillaume Dera                                                                           | [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/); recolored pink                                                                                           |
| `glucose-transparent.svg`    | [Glucose ball-and-stick](https://commons.wikimedia.org/wiki/File:Glucose_ball-and-stick.svg), Carlos Francisco Cruz Fierro                                                                                      | [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/)                                                                                                           |
| `caffeine-transparent.svg`   | [Caffeine 2D skeletal formula](https://commons.wikimedia.org/wiki/File:Caffeine-2D-skeletal.svg), Benjah-bmm27                                                                                                  | Public domain; recolored tan                                                                                                                                            |
| `water-transparent.svg`      | [Water molecule](https://commons.wikimedia.org/wiki/File:Water_molecule.svg), Sakurambo, corrected by Plenz                                                                                                     | Public domain                                                                                                                                                           |

## Large-life and creature silhouettes

The files in `creatures/` are transparent vector silhouettes retained for provenance only. They are no longer referenced by the scale list. All PhyloPic files below are under [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/) or the [Public Domain Mark 1.0](https://creativecommons.org/publicdomain/mark/1.0/), as shown on each linked source page.

| Local file                | Source                                                                                                                                                              |
| ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `blue-whale.svg`          | [_Balaenoptera musculus_](https://www.phylopic.org/images/6ca9f0b7-cacb-45cc-9229-1b672d55b15b), PhyloPic                                                           |
| `african-elephant.svg`    | [_Loxodonta africana_](https://www.phylopic.org/images/51c89c19-6ef1-4d8e-8de6-2a4b6e8f66c8), PhyloPic                                                              |
| `giraffe.svg`             | [_Giraffa_](https://www.phylopic.org/images/bbce74cf-4df3-4b7d-8b1d-f5b24dd3264a), An Ignorant Atheist                                                              |
| `saltwater-crocodile.svg` | [_Crocodylus porosus_](https://www.phylopic.org/images/acb7e630-7491-4caa-9717-b3d847ecb8d7), Margot Michaud                                                        |
| `komodo-dragon.svg`       | [_Varanus komodoensis_](https://www.phylopic.org/images/ce6a78bc-3ef1-4d60-ab40-113eb84c7802), Steven Traver                                                        |
| `emperor-penguin.svg`     | [_Aptenodytes forsteri_](https://www.phylopic.org/images/f2e02022-2700-484d-a66d-b2a900030371), PhyloPic                                                            |
| `green-sea-turtle.svg`    | [_Chelonia mydas_](https://www.phylopic.org/images/6cebfd77-1ad5-449f-8440-c6f9f18f41d8), PhyloPic                                                                  |
| `common-raven.svg`        | [_Corvus corax_](https://www.phylopic.org/images/b4e2e9ef-2b55-4c5e-99b5-5b0db859f59b), Caleb M. Gordon                                                             |
| `giant-african-snail.svg` | [_Lissachatina fulica_](https://www.phylopic.org/images/8c89f14e-7c7b-4844-b0c3-dd3f90818660), Ferran Sayol                                                         |
| `american-bullfrog.svg`   | [_Rana catesbeiana_](https://www.phylopic.org/images/77f50b2e-9679-4ded-9faf-ff77d490c40a), Chuanixn Yu                                                             |
| `monarch-butterfly.svg`   | [_Danaus plexippus_](https://www.phylopic.org/images/e2cdafc4-2e97-45e3-8799-1a965fc24d85), Andy Wilson                                                             |
| `praying-mantis.svg`      | [_Mantis religiosa_](https://www.phylopic.org/images/c5a14ad6-6d6f-49db-97b9-680cb36f8646), PhyloPic                                                                |
| `dragonfly.svg`           | [_Aeshna juncea_](https://www.phylopic.org/images/9b2ec25e-1b65-49d9-9f25-bf5cf6dedb52), TekuraDF                                                                   |
| `honey-bee.svg`           | [_Apis mellifera_](https://www.phylopic.org/images/f551f54e-1e17-4b0e-985c-74d34a53cb63), Lubna Maherally                                                           |
| `ladybird-beetle.svg`     | [_Coccinella_](https://www.phylopic.org/images/87b5e182-6fcf-40c7-af75-af41a04ca5fd), Amy Beauvois                                                                  |
| `ant.svg`                 | [_Martialis heureka_](https://www.phylopic.org/images/f4d28481-3b28-4cdb-9877-9b9d4f07e5f2), PhyloPic                                                               |
| `water-flea.svg`          | [_Daphnia_](https://www.phylopic.org/images/0a74e769-0641-4c1e-be30-9e25f69d3cd6), Kamil S. Jaron                                                                   |
| `human.svg`               | [Man standing silhouette](https://commons.wikimedia.org/wiki/File:Man_standing_silhouette.svg), pitr, [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/) |

## Bioicons SVGs

The SVGs came from [Bioicons](https://bioicons.com/) at pinned commit [`d29e766ea7580b8063c4f47b29e872db40a4d979`](https://github.com/duerrsimon/bioicons/tree/d29e766ea7580b8063c4f47b29e872db40a4d979). Bioicons' application license does not replace the individual artwork licenses; the repository's license directory and creator directory are authoritative.

### Servier Medical Art — CC BY 3.0

The following files are Bioicons' Servier artwork under [CC BY 3.0 Unported](https://creativecommons.org/licenses/by/3.0/):

- `actin.svg` (`actin-filament.svg`), `adenovirus.svg` (`adeno-virus.svg`), `antibody.svg` (`antibody-2.svg`), `collagen.svg` (`collagen-3d.svg`)
- `enzyme.svg` (`enzyme-green-3d.svg`), `hemoglobin.svg` (`protein-12.svg`), `herpes.svg` (`herpes-simplex-virus.svg`), `hiv.svg` (`hiv-virus.svg`)
- `influenza.svg` (`influenza-virus.svg`), `insulin.svg` (`protein-3.svg`), `membrane.svg` (`membrane-3d-bluepurple.svg`), `microtubule.svg`
- `mimivirus.svg` (`hepatitis-virus-interior.svg`), `nucleus.svg` (`nucleus-full-3d.svg`), `quark.svg`, `rotavirus.svg` (`hepatits-virus.svg`)
- `skin-cell.svg` (`keratinocyte-2.svg`), `white-blood-cell.svg` (`macrophage.svg`)

Credit: “Image adapted from [Servier Medical Art](https://smart.servier.com/), licensed under CC BY 3.0.”

### DBCLS TogoTV — CC BY 4.0

- `bacillus.svg` (`Bacillus_subtilis.svg`)
- `cyanobacterium.svg` (`Cyanobacteria.svg`)
- `protein.svg` (`Protein_colored.svg`)

Required credit: “© 2016 [DBCLS TogoTV](https://dbarchive.biosciencedbc.jp/data/togo-pic/LATEST/README_e.html) / [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/).”

### Other attributed Bioicons art

- `coccus.svg` (`Bacteria1M_coccus.svg`) and `egg-cell.svg` (`Egg_cell.svg`) — SwissBioPics, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)
- `plant-cell.svg` (`Structure_of_Plant_Cell.svg`) — Durvesh Burhade and Niliksha Patel, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)
- `poxvirus.svg` — Alejandro Matía, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/)
- `sars-cov-2.svg` — Hanna Vega, [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/)

### Additional transparent vector art

- `plant-cell-clean.svg` (`Simple diagram of plant cell (blank).svg`) — domdomegg, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), via [Wikimedia Commons](<https://commons.wikimedia.org/wiki/File:Simple_diagram_of_plant_cell_(blank).svg>)
- `chloroplast.svg` (`Torisan Chloroplast`) — Torisan / Open Clip Art Library, public domain, via [Clker](https://www.clker.com/clipart-16397.html). Cropped to the illustration bounds for this game.

### Bioicons CC0 art

These files are dedicated to the public domain under [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/); creator names are retained as a courtesy:

- `atp.svg` — Simon Dürr
- `mitochondrion.svg` — jaiganesh
- `nucleosome.svg` — Xi Chen
- `phage.svg` — James Lloyd
- `phospholipid.svg` — Cléber Gomes
- `poliovirus.svg` (`12_wp_plaque.svg`) — KeHan
- `rhinovirus.svg` (`virus-sketch.svg`) — Marcel Tisch
- `sperm.svg` — Xi Chen

## Legacy microscopy photos from Wikimedia Commons

These older opaque files remain in the source archive for provenance but are no longer referenced by Zoom to Zero.

| Local file       | Source and creator                                                                                                                                           | License                                                         |
| ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------- |
| `dust-mite.jpg`  | [House Dust Mite](https://commons.wikimedia.org/wiki/File:House_Dust_Mite.jpg), U.S. Food and Drug Administration employee                                   | Public domain, U.S. government/FDA work                         |
| `hair.jpg`       | [Hair micrograph 1](https://commons.wikimedia.org/wiki/File:Hair_micrograph_1.jpg)                                                                           | [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/)   |
| `amoeba.jpg`     | [Amoeba proteus](https://commons.wikimedia.org/wiki/File:Amoeba_proteus.jpg), Cymothoa exigua                                                                | [CC BY-SA 3.0](https://creativecommons.org/licenses/by-sa/3.0/) |
| `pollen.jpg`     | [Misc pollen colorized](https://commons.wikimedia.org/wiki/File:Misc_pollen_colorized.jpg), Dartmouth Electron Microscope Facility; colorization by Medium69 | Public domain                                                   |
| `tardigrade.jpg` | [Tardigrade under microscope](https://commons.wikimedia.org/wiki/File:Tardigrade_under_microscope.jpg), DSparrow14                                           | [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/) |

The pollen colors are an illustrative colorization and are not necessarily the specimens' natural colors.

## Legacy PubChem molecule renders

These older opaque files remain in the source archive for provenance but are no longer referenced by Zoom to Zero.

The 300 × 300 structure renders were generated by [PubChem](https://pubchem.ncbi.nlm.nih.gov/) and downloaded locally:

- `water.png` — [water, CID 962](https://pubchem.ncbi.nlm.nih.gov/compound/962)
- `glucose.png` — [D-glucose, CID 5793](https://pubchem.ncbi.nlm.nih.gov/compound/5793)
- `caffeine.png` — [caffeine, CID 2519](https://pubchem.ncbi.nlm.nih.gov/compound/2519)

Please cite PubChem according to its [citation guidelines](https://pubchem.ncbi.nlm.nih.gov/docs/citation-guidelines).

## Adaptation note

Several local labels intentionally use generic source art as a playful visual proxy: `hemoglobin.svg`, `insulin.svg`, `mimivirus.svg`, `poliovirus.svg`, `rhinovirus.svg`, and `rotavirus.svg`. They are not taxon- or molecule-specific scientific plates. Attribution, license links, original filenames, and an indication of modifications must travel with any redistributed adaptation; CC BY-SA artwork must remain under the same or a compatible license.