THE ANIMAL FILES

Housefly

Musca domestica

A sponge-like mouth and tasting feet make a different kind of diner.

A housefly does not eat by chewing like a person or a beetle with large jaws. Its mouthparts collect liquid, while sensory structures on its feet help assess a surface. Its life cycle adds another surprise: a small adult is not simply a younger version of a large one.[1]

Follow the evidence ↓
Housefly
Image: James K. Lindsey · Commons · CC BY-SA 3.0
Functional wings
One pair, with balancing halteres[1]
Mouthparts
A sponge-like liquid-feeding tip[1]
Young stage
Legless larvae called maggots[1]

The mouth collects rather than chews

The flexible proboscis ends in a fleshy labellum with fine grooves that collect fluids. Saliva can help soften food at the surface.[1]

The feet also gather information

Taste receptors on the feet allow a housefly to assess substances it walks across. Foot structures also help it cling to smooth surfaces. Meanwhile, the reduced hind wings form halteres involved in flight stability.[1]

Growing happens before the adult emerges

Larvae feed in moist organic material, then move to a different setting for pupation. The adult emerges from the pupal case and does not continue growing in body size. Conditions during the larval stage therefore help explain adult size; a small fly need not be an adult that has only just hatched.[1]

A COMMON MIX-UP

Will a tiny housefly grow into a larger adult?

No. Once the adult has emerged, body growth has ended. Size differences can reflect larval conditions rather than a simple age sequence among the winged flies standing side by side.[1]

TRY A LITTLE REASONING

Why would rubbing its feet matter before walking elsewhere?

Reveal the explanation

The feet are sensory surfaces as well as supports. Cleaning them helps the fly sample what it encounters next, so a seemingly idle movement can be understood in relation to the structures used for tasting.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — Housefly (fixed revision; adapted and translated)
  2. NCBI Taxonomy — Musca domestica (identity and classification)

Last fact check:

One discovery leads to another

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