A dew-covered orb web strung between garden plants in soft autumn morning light
AI-generated image, not a photograph of a real person or place.
doodlextruder

HOW NATURE EXTRUDES

Liquid in,
thread out.

0.001 mm a typical silk line

  • Made as a liquid
  • Drawn into a fibre
  • A silk for each job
  • Spun near room temperature

A spider is a tiny, silent extrusion machine.

Silk is made as a thick liquid inside the body, then drawn out through spigots on the spinnerets as a solid fibre. One spider can make several silks, each tuned for a different job.

Updated

Compare the silks

THE SHORT ANSWER

A spinneret is
a living nozzle.

Silk glands make the liquid, the duct turns it into a fibre,
and the spinnerets lay it down where it is needed.

SPINNING

Liquid becomes fibre

Silk flows as a liquid crystal through a long, narrowing duct that draws out water. An acid bath and pulling stress then turn it into a solid thread.

Compare the silks

SILKS

Different silks, different jobs

Ten types of silk gland are known in spiders, and up to eight can be found in one species. An orb web mixes strong frame silk with stretchy, sticky spiral silk.

See the numbers

LOOK

Spot one in autumn

The UK garden spider builds webs up to 40 cm wide. Look for them on windows and doorways, most likely from April to November.

How to look

THREE SILKS IN ONE WEB

Which thread
does what?

Pick a part of an orb web to see which silk it is made of. The bar shows how strong that silk is, as the Australian Museum describes it.

Silk check

Choose a thread
Frame and spokesDragline silk

Made in the major ampullate glands, which also supply the spider's safety line. Its tensile strength is greater than that of mild steel.

The catching spiralFlagelliform silk

Weaker than frame silk but very much more stretchy, so a fast insect's impact is absorbed instead of tearing through or bouncing off.

The sticky dropsAggregate silk

The only silk that stays liquid after leaving the spigot. It coats the spiral line, then breaks up into droplets with a very sticky core.

Source: Australian Museum, Silk: the spider's success story.

Based on the Australian Museum's guide to spider silk.

TWO NUMBERS WORTH KNOWING

Thin as a hair,
tough as anything.

One figure on how fine silk is,
one on how far a record-breaking spider can span.

0.001–0.004 mm

A typical spider silk line

A spider's silk line is usually only about 0.001 to 0.004 mm thick. A single fibril of cribellate silk is about 0.00001 mm thick, and thousands combine into one thread.

THICKNESS · AUSTRALIAN MUSEUM

25 m

Anchor threads of Darwin's bark spider

This Madagascan spider hangs giant webs over rivers on anchor threads as long as 25 metres. Its dragline silk was more than twice as tough as any silk described before.

TOUGHNESS · PLOS ONE 2010

A 2001 study in Nature explained that because the spinning liquid is liquid crystalline, spiders can draw it into a hardened fibre during extrusion using minimal force, at close to room temperature and with water as the solvent.

FOUR THINGS TO LOOK FOR

Read a web
on a dewy morning.

Close-up of dewdrops beaded along the spiral threads of an orb web
AI-generated image, not a photograph of a real person or place.

Autumn is when spiders and their webs become most noticeable in the UK, although they are around all year. Dew makes the different threads easy to see.

  1. Find the frame

    The straight outer lines and spokes are dragline silk, the strong framework of the web.

  2. Follow the spiral

    The tightly wound spiral is the stretchy catching silk, beaded with tiny sticky droplets.

  3. Check the hub

    The centre has no catching silk, so the spider can wait there without sticking.

  4. Look, don't touch

    A web is the spider's way of catching food. Watching from a short distance leaves it working.

BETTER THAN A FACTORY

Fibre made
without the heat.

A garden spider with a pale cross pattern on its back climbing fine silk threads against a soft green background
AI-generated image, not a photograph of a real person or place.

Spider silk is spun at close to ambient temperature and pressure, using water as the solvent. Inside the spinneret the fibre is drawn down internally, a step the 2001 Nature study says is not seen in industrial fibre processing.

The spider controls how its proteins fold and crystallise inside the spinneret. Researchers have suggested that copying this process could one day allow silk-based fibres to be produced industrially under similarly gentle conditions.

Questions

Questions people ask

How do spiders make silk?

Silk glands in the abdomen produce a liquid protein. It flows through a narrowing duct that removes water, passes through a mild acid bath and is pulled into a solid fibre as it leaves the spigots on the spinnerets.

Is spider silk really stronger than steel?

The Australian Museum says the tensile strength of dragline silk, used for web frames and safety lines, is greater than that of mild steel and almost all artificial fibres.

Why don't spiders stick to their own webs?

They touch the web only with their leg tips, clean their legs regularly, and keep the hub and other areas free of sticky catching silk.

How many kinds of silk can one spider make?

Ten types of silk gland are known in spiders, and up to eight can be present in a single species, each making silk with different properties.

When can I see garden spider webs in the UK?

The Woodland Trust says you are most likely to see garden spiders from April to November. Their webs can be up to 40 cm wide and are often built on windows and doorways.

Sources

Where the facts come from

  1. Australian Museum: Silk, the spider's success story
  2. Vollrath and Knight (2001), Liquid crystalline spinning of spider silk, Nature
  3. Agnarsson, Kuntner and Blackledge (2010), Bioprospecting finds the toughest biological material, PLOS ONE
  4. Woodland Trust: Garden spider (Araneus diadematus)
  5. Natural History Museum: Spider season, who lives on a web like this?

ABOUT THIS NAME

Interested in leasing doodlextruder.com?

doodlextruder.com is part of the DoodleSale portfolio. It isn't in an auction right now, but you can ask about leasing it.

Ask about this name