upper waypoint

This Mushroom Tricks Flies By Faking Its Own Death

Save ArticleSave Article
Failed to save article

Please try again

The cage fungus looks and smells like decaying meat — on purpose. Its goopy lattice gives off a rotten odor that attracts flies, which help spread its spores far and wide. It’s like a bee to a flower, but way more macabre and putrid.


What is that terrible smell?

Is it spoiled fruit?

A rotten egg?

A dead animal?


It’s actually coming from this cage fungus — and it’s in the absolute prime of its life.

That horrible smell is part of an elaborate hoax to fake its own death.

Like most mushrooms, what you see is only a small part of the organism.

The vast majority is hidden below the surface — in an expansive network of miniscule threads called the mycelium.

Cage fungus is saprobic — the mycelium eats dead and rotting wood, digesting the cellulose and returning nutrients to the soil.

When the weather is warm and wet and there’s plenty of wood around, the mycelium creates an “egg” — this brain-looking thing — that pops up above ground.

A white leathery membrane protects the egg as it grows and stretches.

Until it cracks open.

The spongy lattice bursts outward.

After a few hours it looks — and smells — like a basket made of decaying flesh.

The interior surfaces of the lattice are coated in a sickly brown slime called gleba.

That horrendous odor emanates from those sticky globs.

The open lattice shape helps the stench spread in the breeze.

But to a fly, that reek is irresistible.

It screams: rotting carcass! A delectable meal, or a place to lay their eggs.

The gaps in the lattice are just the right size for the flies to pop in and out.

They traipse around, gobbling up the goo.

The flies love it, but what’s in it for the fungus?

Well, the fungus needs something that the flies have — wings.

While many mushrooms spread their spores by releasing them into the wind, the cage fungus gets the flies to do all the work

As they feed, the flies unintentionally down millions of the fungus’ microscopic spores, hidden inside the dark slime.

The gleba also clings to the flies’ feet.

When the flies lift off, they take the spores with them, spreading them far and wide.

After about a day the lattice starts to collapse.

Having successfully spread its spores, this is the end of its story — or is it?

When the conditions are right, the fungus will pop up more eggs year after year — continuing its deception for the sake of future generations.

Hi, Laura here.

If you think flies and fungus make a winning combination. … Deep Look’s got another episode for you.

This killer fungus turns flies … into zombies.

And —- a special shoutout and thank you to Jessica Ho, whose generous monthly support on Patreon helps make Deep Look possible.

If you want to support us on Patreon, there’s a link in the description.


lower waypoint
next waypoint
Holiday Weekend Storms On Tap Could Bring Flooding to the Bay AreaLeap Year 2024: Why Do We Get an Extra Day?Battle Over San Francisco's Coastal Development Sparks Statewide ConcernsFebruary's Storms Doubled California Snowpack, March Could Bring More Wet WeatherCalifornia Releases Formal Proposal to End Fracking in the StateFrom Giant Isopods to Glowing Jellies, This New Monterey Bay Aquarium Exhibit Features Deep-Sea Creatures Never Seen BeforeAll of California Is Now Out of Drought, According to U.S. Drought MonitorHow Mosquitoes Use Six Needles to Suck Your BloodWinter Rains Leave Forests Flush With FungiWhere to See Wildflowers Near You in the Bay Area (Plus, the Science Behind the 'Super Bloom')