A fern’s microscopic catapult.

How does a fern load a microscopic catapult?

Setting up the mechanism…

Annulus loading: 0.00relative
Stored elastic energy: 0.00relative

Spores released: 0spores

Fit the specimen and set conditions before running.

How does a fern load a microscopic catapult?

Drying water-filled annulus cells stores elastic curvature. Cavitation breaks the liquid tension and triggers rapid recoil, releasing the spores.

evaporation → elastic loading → cavitation → recoil

What this model simplifies

Polypodium-style 13-cell annulus. Hydration, energy and cavitation threshold are normalized teaching variables. Biological recoil is slowed; no real pressure threshold is predicted.

Read the source · pmc.ncbi.nlm.nih.gov ↗

Put it to work.

Release spores only after loading the hydrated annulus.

Make it work.

Load the annulus and release spores.

Run

Fine adjustments 1

Relative annulus hydration

A fern’s microscopic catapult.

How does a fern load a microscopic catapult?

Loading the experiment…

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Figuvo is a place to look inside everyday things, build a connection, and discover the idea behind them.

177 interactive experiments. Each has a working model and a challenge to test what you found.

The original inspiration

Levers & fulcrums The surprising gyroscope The field cannon Inside the human body

Original demonstrations by The Bugged Dev. The teaching models and interactions here are new implementations.

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New teaching models inspired by public builds shared around Anatomy.

Anatomy · the original announcement How a rocket pushes through space · Gustavo Inside a tactile key switch · @retaqib Pressure through the coffee bed · Gustavo The overbalance wheel · Shawn A seconds pendulum clock · @Baconbrix Three feet on the ground · Soju Inside a layered particle detector · Yash A double-deck pressure cabin · Charlie Leave the spent booster behind · @quantapar Principal, interest and escrow · Sean Gear a Martian year · @samani_Two balls in, two balls out · @samani_Two slits, one probability pattern · @samani_Join through a clear plastic cover · Josh Brown Lay pipe without a sharp bend · @Phi10w Eight cylinders and a blower · @love4hxns Four columns under a Joglo roof · Nur Asyrof An office for dependent tasks · Yaroslav Yablonski One image, six editable layers · Meng To The Redis caching machine · @uviii_03 Inside the Sony CMD-J5 · Ann Afterburner thrust stand · Joshua Guo Open-back headphones · Surajan Shrestha Two-thread lockstitch machine · @slashui Signal factory · Dhruval Golakiya

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A fern’s microscopic catapult.

How does a fern load a microscopic catapult?

Setting up the mechanism…

Annulus loading: 0.00relative
Stored elastic energy: 0.00relative

Spores released: 0spores

Fit the specimen and set conditions before running.

How does a fern load a microscopic catapult?

Drying water-filled annulus cells stores elastic curvature. Cavitation breaks the liquid tension and triggers rapid recoil, releasing the spores.

evaporation → elastic loading → cavitation → recoil

What this model simplifies

Polypodium-style 13-cell annulus. Hydration, energy and cavitation threshold are normalized teaching variables. Biological recoil is slowed; no real pressure threshold is predicted.

Read the source · pmc.ncbi.nlm.nih.gov ↗

Put it to work.

Release spores only after loading the hydrated annulus.

Make it work.

Load the annulus and release spores.

Run

Fine adjustments 1

Relative annulus hydration