What Ants, Cells & Atoms is

Ants, Cells & Atoms is a field guide for curious adults and families to the world below the width of a hair: living things and molecules too small to see without help, plus the parts of insects that only make sense once they are magnified. Every entry gives a real, sourced size, places it on a powers-of-ten ladder, and explains which physical effects come out on top at that size.

The name starts with ants, but this is not an ant site. The three words run from large to small and mark three of the four sections; the fourth compares and estimates across all of them.

• Microscopic Life: diatoms, plankton, protists, slime molds and yeast, by structure, behavior and ecology, never by disease.
• Insect Forms & Behavior: insects and spiders at the scale where their bodies work.
• Molecule Shapes: everyday molecules and crystals, drawn from published coordinates.
• Scale & Estimates: size comparisons and Fermi estimates, each tied to a question people ask.

Who the entries are for

The entries are for the reader who searches for one named thing, a diatom, a water strider or the water molecule: an adult with a question, or a family looking something up together. Hobby microscope users, teachers and students who want a chart they can cite, and anyone who enjoys a back-of-the-envelope estimate are welcome too.

What this site does not do

Some questions are answered better elsewhere. Nothing here covers disease, infection, symptoms or treatment; microbes that can cause illness appear only for their structure and ecology. Nothing covers bites or stings, allergies, repellents or pest control. There is no advice on buying a microscope or a camera, no dose or effect for any drug or supplement, and no identification of a creature from a photograph. Students get working, figures and data to follow, not an answer page to copy.

The stance behind every entry

Small things are not scaled-down versions of big things. The laws of physics are the same at every size, but when size, speed and the surrounding fluid change, a different effect comes out on top. To read a small creature, first ask which effect is in charge under its conditions. That is this site's working stance, not a scientific claim.

In this site's shorthand, every scale shares one statute book, but the local court cites different clauses: gravity is still on the books for a swimming bacterium, yet viscosity is the clause that decides almost every case there. Said plainly: no force switches off; their relative sizes change, and each entry names the one that dominates and the conditions that make it so.

Several positions follow. An ant lifting many times its own body weight is mostly geometry, not a superpower: scaled up to human size with the same shape, every strength-for-weight ratio would shrink more than a hundredfold. Ball-and-stick drawings mislead as much as they help, so every molecule here is also shown space-filling, with a note on which drawing is closer to the electron cloud. A microbe is a neighbor by default, not a threat. And a logarithmic axis is the only honest axis for things this small, which is why the ladder on every entry is logarithmic.

How entries are checked

Ants, Cells & Atoms does not collect samples and owns no microscope. Every micrograph comes from a named, openly licensed source. The working rules:

• Sizes and counts. Every size and every count carries a source and a power-of-ten label such as [10⁻⁴ m]. Original measurement papers rank above summary articles and textbooks. When sources disagree, the entry gives the range, not an average.
• Estimates. Every input has a source. The arithmetic is written out step by step with units, and the inputs and results are in a CSV you can download and recompute. Each calculated estimate is run by two independent routes. If they differ by more than a factor of ten, the entry is held until the arithmetic is rerun, the responsible input is named with its source, and the conclusion is narrowed to the range both routes support.
• Species names. Scientific names and higher groups are compared against GBIF and the Catalogue of Life. When a name has changed, both names appear.
• Molecules. Each number is marked measured or computed. Structure drawings are made by this site from published structure data, and each states whether it shows a computed conformer or an experimentally determined geometry. The PubChem CID is given so you can compare.
• Photographs. Every photograph's license is recorded image by image. Every micrograph caption declares where its color comes from: native, stain, false color or fluorescence. A size is read off a photograph only when the image has a scale bar or a traceable calibration; otherwise the entry quotes a published measurement.
• Diagrams and illustrations. Diagrams are drawn from data. Illustrations are labeled as such, are never presented as photographs and are not to scale; scale is the ladder's job.
• Rules with exceptions. A pattern that has exceptions is written as "most" or "under these conditions", not as a law.
• What recomputation proves. Rerunning the arithmetic checks the calculation, not the inputs; whether an input is right is a question for its source.

Reporting an error

If something looks wrong, write to contact@antscellsandatoms.com; the same link sits at the foot of every page. A confirmed error in a number is fixed within 72 hours. Every correction is recorded at the foot of the entry and on the corrections page: the date, what was wrong, what it says now and whether a reader or a recheck found it. An error of a factor of ten or more also gets a notice at the top of the entry for 30 days.

Reusing figures and citing a page

Diagrams and data tables made by this site are released under CC BY 4.0; photographs keep the licenses of their sources, and illustrations stay under this site's own terms. The attribution line and the dataset credits are on the image and data rights page. Every entry ends with a Cite this page block: title, publication date, date of the last substantive revision and permanent address. This site does not issue DOIs.

The Zoom ladder

Every entry carries, under its short answer, a horizontal ladder from 10 cm, about the width of a hand, to 0.1 nm, the scale of an atom, one power of ten per rung, with the subject marked on it. How to read the Zoom ladder explains the rungs, the labels and the two reference lines.

Three terms you will meet

Three terms are this site's own. The syrup line is the point, for a given fluid, temperature and speed, where a swimmer's Reynolds number drops to 1 and stickiness starts to beat inertia; change the speed or the fluid and it moves. Borrowed color is any color in a micrograph that does not belong to the organism, added by a stain, a fluorescent marker or false coloring; every micrograph caption here declares it. The stick fiction is the habit of drawing chemical bonds as solid rods, which suggests empty space between atoms; every entry that shows only a ball-and-stick drawing names it.